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Zhuo J, Raghavan P, Li J, Roys S, Njonkou Tchoquessi RL, Chen H, Wickwire EM, Parikh GY, Schwartzbauer GT, Grattan LM, Wang Z, Gullapalli RP, Badjatia N. Longitudinal assessment of glymphatic changes following mild traumatic brain injury: Insights from perivascular space burden and DTI-ALPS imaging. Front Neurol 2024; 15:1443496. [PMID: 39170078 PMCID: PMC11335690 DOI: 10.3389/fneur.2024.1443496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Accepted: 07/08/2024] [Indexed: 08/23/2024] Open
Abstract
Introduction Traumatic brain injury (TBI) even in the mild form may result in long-lasting post-concussion symptoms. TBI is also a known risk to late-life neurodegeneration. Recent studies suggest that dysfunction in the glymphatic system, responsible for clearing protein waste from the brain, may play a pivotal role in the development of dementia following TBI. Given the diverse nature of TBI, longitudinal investigations are essential to comprehending the dynamic changes in the glymphatic system and its implications for recovery. Methods In this prospective study, we evaluated two promising glymphatic imaging markers, namely the enlarged perivascular space (ePVS) burden and Diffusion Tensor Imaging-based ALPS index, in 44 patients with mTBI at two early post-injury time points: approximately 14 days (14Day) and 6-12 months (6-12Mon) post-injury, while also examining their associations with post-concussion symptoms. Additionally, 37 controls, comprising both orthopedic patients and healthy individuals, were included for comparative analysis. Results Our key findings include: (1) White matter ePVS burden (WM-ePVS) and ALPS index exhibit significant correlations with age. (2) Elevated WM-ePVS burden in acute mTBI (14Day) is significantly linked to a higher number of post-concussion symptoms, particularly memory problems. (3) The increase in the ALPS index from acute (14Day) to the chronic (6-12Mon) phases in mTBI patients correlates with improvement in sleep measures. Furthermore, incorporating WM-ePVS burden and the ALPS index from acute phase enhances the prediction of chronic memory problems beyond socio-demographic and basic clinical information. Conclusion ePVS burden and ALPS index offers distinct values in assessing glymphatic structure and activity. Early evaluation of glymphatic function could be crucial for understanding TBI recovery and developing targeted interventions to improve patient outcomes.
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Affiliation(s)
- Jiachen Zhuo
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Prashant Raghavan
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jiang Li
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Steven Roys
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Rosy Linda Njonkou Tchoquessi
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Hegang Chen
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Emerson M. Wickwire
- Department of Psychiatry and Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Gunjan Y. Parikh
- Program in Trauma, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Gary T. Schwartzbauer
- Program in Trauma, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Lynn M. Grattan
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Ze Wang
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Rao P. Gullapalli
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Neeraj Badjatia
- Program in Trauma, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
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Pan J, Qiu Z, Fu G, Liang J, Li Y, Feng Y, Zhang X, Lv X. Non-complete recovery of temporal lobe white matter diffusion metrics at one year Post-Radiotherapy: Implications for Radiation-Induced necrosis risk. Radiother Oncol 2024; 199:110420. [PMID: 39029591 DOI: 10.1016/j.radonc.2024.110420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 06/20/2024] [Accepted: 07/01/2024] [Indexed: 07/21/2024]
Abstract
BACKGROUND Temporal lobe (TL) white matter (WM) injuries are often seen early after radiotherapy (RT) in nasopharyngeal carcinoma patients (NPCs), which fail to fully recover in later stages, exhibiting a "non-complete recovery pattern". Herein, we explored the correlation between non-complete recovery WM injuries and TL necrosis (TLN), identifying dosimetric predictors for TLN-related high-risk WM injuries. METHODS We longitudinally examined 161 NPCs and 19 healthy controls employing multi-shell diffusion MRI. Automated fiber-tract quantification quantified diffusion metrics within TL WM tract segments. ANOVA identified non-complete recovery WM tract segments one-year post-RT. Cox regression models discerned TLN risk factors utilizing non-complete recovery diffusion metrics. Normal tissue complication probability (NTCP) models and dose-response analysis further scrutinized RT-related toxicity to high-risk WM tract segments. RESULTS Seven TL WM tract segments exhibited a "non-complete recovery pattern". Cox regression analysis identified mean diffusivity of the left uncinate fasciculus segment 1, neurite density index (NDI) of the left cingulum hippocampus segment 1, and NDI of the right inferior longitudinal fasciculus segment 1 as TLN risk predictors (hazard ratios [HRs] with confidence interval [CIs]: 1.45 [1.17-1.81], 1.07 [1.00-1.15], and 1.15 [1.03-1.30], respectively; all P-values < 0.05). In NTCP models, D10cc.L, D20cc.L and D10cc.R demonstrated superior performance, with TD50 of 37.22 Gy, 24.96 Gy and 37.28 Gy, respectively. CONCLUSIONS Our findings underscore the significance of the "non-complete recovery pattern" in TL WM tract segment injuries during TLN development. Understanding TLN-related high-risk WM tract segments and their tolerance doses could facilitate early intervention in TLN and improve RT protocols.
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Affiliation(s)
- Jie Pan
- Department of Medical Imaging, State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, No. 651 Dongfeng Road East, Guangzhou 510060, China
| | - Ziru Qiu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China; Guangdong Provincial Key Laboratory of Medical Image Processing and Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, China
| | - Gui Fu
- Department of Medical Imaging, State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, No. 651 Dongfeng Road East, Guangzhou 510060, China
| | - Jiahui Liang
- Department of Medical Imaging, State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, No. 651 Dongfeng Road East, Guangzhou 510060, China
| | - Yunpeng Li
- Department of Medical Imaging, State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, No. 651 Dongfeng Road East, Guangzhou 510060, China
| | - Yanqiu Feng
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China; Guangdong Provincial Key Laboratory of Medical Image Processing and Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, China; Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence & Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China; Department of Rehabilitation, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Xinyuan Zhang
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China; Guangdong Provincial Key Laboratory of Medical Image Processing and Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, China.
| | - Xiaofei Lv
- Department of Medical Imaging, State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, No. 651 Dongfeng Road East, Guangzhou 510060, China.
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Oeschger JM, Tabelow K, Mohammadi S. Investigating apparent differences between standard DKI and axisymmetric DKI and its consequences for biophysical parameter estimates. Magn Reson Med 2024; 92:69-81. [PMID: 38308141 DOI: 10.1002/mrm.30034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 02/04/2024]
Abstract
PURPOSE The purpose of the study is to identify differences between axisymmetric diffusion kurtosis imaging (DKI) and standard DKI, their consequences for biophysical parameter estimates, and the protocol choice influence on parameter estimation. METHODS Noise-free and noisy, synthetic diffusion MRI human brain data is simulated using standard DKI for a standard and the fast "199" acquisition protocol. First the noise-free "baseline" difference between both DKI models is estimated and the influence of fiber complexity is investigated. Noisy data is used to establish the signal-to-noise ratio at which the baseline difference exceeds noise variability. The influence of protocol choices and denoising is investigated. The five axisymmetric DKI tensor metrics (AxTM), the parallel and perpendicular diffusivity and kurtosis and mean of the kurtosis tensor are used to compare both DKI models. Additionally, the baseline difference is also estimated for the five parameters of the WMTI-Watson model. RESULTS The parallel and perpendicular kurtosis and all of the WMTI-Watson parameters had large baseline differences. Using a Westin or FA mask reduced the number of voxels with large baseline difference, that is, by selecting voxels with less complex fibers. For the noisy data, precision was worsened by the fast "199" protocol but adaptive denoising can help counteract these effects. CONCLUSION For the diffusivities and mean of the kurtosis tensor, axisymmetric DKI with a standard protocol delivers similar results as standard DKI. Fiber complexity is one main driver of the baseline differences. Using the "199" protocol worsens precision in noisy data but adaptive denoising mitigates these effects.
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Affiliation(s)
- Jan Malte Oeschger
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Karsten Tabelow
- Weierstrass Institute for Applied Analysis and Stochastics, Berlin, Germany
| | - Siawoosh Mohammadi
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Sachsen, Germany
- Max Planck Research Group MR Physics, Max Planck Institute for Human Development, Berlin, Germany
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Gard A, Kornaropoulos EN, Portonova Wernersson M, Rorsman I, Blennow K, Zetterberg H, Tegner Y, De Maio A, Markenroth Bloch K, Björkman-Burtscher I, Pessah-Rasmussen H, Nilsson M, Marklund N. Widespread White Matter Abnormalities in Concussed Athletes Detected by 7T Diffusion Magnetic Resonance Imaging. J Neurotrauma 2024; 41:1533-1549. [PMID: 38481124 DOI: 10.1089/neu.2023.0099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024] Open
Abstract
Sports-related concussions may cause white matter injuries and persistent post-concussive symptoms (PPCS). We hypothesized that athletes with PPCS would have neurocognitive impairments and white matter abnormalities that could be revealed by advanced neuroimaging using ultra-high field strength diffusion tensor (DTI) and diffusion kurtosis (DKI) imaging metrics and cerebrospinal fluid (CSF) biomarkers. A cohort of athletes with PPCS severity limiting the ability to work/study and participate in sport school and/or social activities for ≥6 months completed 7T magnetic resonance imaging (MRI) (morphological T1-weighed volumetry, DTI and DKI), extensive neuropsychological testing, symptom rating, and CSF biomarker sampling. Twenty-two athletes with PPCS and 22 controls were included. Concussed athletes performed below norms and significantly lower than controls on all but one of the psychometric neuropsychology tests. Supratentorial white and gray matter, as well as hippocampal volumes did not differ between concussed athletes and controls. However, of the 72 examined white matter tracts, 16% of DTI and 35% of DKI metrics (in total 28%) were significantly different between concussed athletes and controls. DKI fractional anisotropy and axial kurtosis were increased, and DKI radial diffusivity and radial kurtosis decreased in concussed athletes when compared with controls. CSF neurofilament light (NfL; an axonal injury marker), although not glial fibrillary acidic protein, correlated with several diffusion metrics. In this first 7T DTI and DKI study investigating PPCS, widespread microstructural alterations were observed in the white matter, correlating with CSF markers of axonal injury. More white matter changes were observed using DKI than using DTI. These white matter alterations may indicate persistent pathophysiological processes following concussion in sport.
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Affiliation(s)
- Anna Gard
- Department of Clinical Sciences Lund, Neurosurgery, Neurology, Lund University, Lund, Sweden
| | - Evgenios N Kornaropoulos
- Department of Clinical Sciences Lund, Diagnostic Radiology, Neurology, Lund University, Lund, Sweden
| | - Maria Portonova Wernersson
- Department of Neurology, Rehabilitation Medicine, Memory Disorders and Geriatrics, Skåne University Hospital, Neurology, Lund University, Lund, Sweden
| | - Ia Rorsman
- Department of Clinical Sciences Lund, Neurology, Lund University, Lund, Sweden
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
| | - Yelverton Tegner
- Department of Health, Education and Technology, Division of Health and Rehabilitation, Luleå University of Technology, Luleå, Sweden
| | - Alessandro De Maio
- Department of Radiological, Oncological and Pathological Sciences. Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Karin Markenroth Bloch
- Department of Clinical Sciences Lund, Lund University Bioimaging Center, Lund University, Lund, Sweden
| | - Isabella Björkman-Burtscher
- Department of Radiology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Hélène Pessah-Rasmussen
- Department of Neurology, Rehabilitation Medicine, Memory Disorders and Geriatrics, Skåne University Hospital, Neurology, Lund University, Lund, Sweden
- Department of Clinical Sciences Lund, Neurology, Lund University, Lund, Sweden
| | - Markus Nilsson
- Department of Clinical Sciences Lund, Diagnostic Radiology, Neurology, Lund University, Lund, Sweden
| | - Niklas Marklund
- Department of Clinical Sciences Lund, Neurosurgery, Lund University, and Skåne University Hospital, Lund, Sweden
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Nguyen P, Albayram M, Tuna I. Intramyelinic edema manifesting as central white matter diffusion restriction associated with brain contusion in pediatric patients. Neuroradiol J 2024:19714009241260796. [PMID: 38856642 DOI: 10.1177/19714009241260796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2024] Open
Abstract
In traumatic brain injury, white matter diffusion restriction can be an imaging manifestation of non-hemorrhagic axonal injury. In this article, a different pattern of widespread white matter diffusion restriction associated with ipsilateral cortical damage, all noted in pediatric and young adult TBI patients, is presented. Its atypical pattern of distribution and extensive scope on imaging suggest excitotoxicity and intramyelinic edema as possible underlying mechanisms.
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Affiliation(s)
- Phuong Nguyen
- Department of Radiology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Mehmet Albayram
- Department of Radiology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Ibrahim Tuna
- Department of Radiology, College of Medicine, University of Florida, Gainesville, FL, USA
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Zhuo J, Raghavan P, Jiang L, Roys S, Tchoquessi RLN, Chen H, Wickwire EM, Parikh GY, Schwartzbauer GT, Grattan LM, Wang Z, Gullapalli RP, Badjatia N. Longitudinal Assessment of Glymphatic Changes Following Mild Traumatic Brain Injury: Insights from PVS burden and DTI-ALPS Imaging. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.06.01.24307927. [PMID: 38854000 PMCID: PMC11160843 DOI: 10.1101/2024.06.01.24307927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Traumatic brain injury (TBI) even in the mild form may result in long-lasting post-concussion symptoms. TBI is also a known risk to late-life neurodegeneration. Recent studies suggest that dysfunction in the glymphatic system, responsible for clearing protein waste from the brain, may play a pivotal role in the development of dementia following TBI. Given the diverse nature of TBI, longitudinal investigations are essential to comprehending the dynamic changes in the glymphatic system and its implications for recovery. In this prospective study, we evaluated two promising glymphatic imaging markers, namely the enlarged perivascular space (ePVS) burden and Diffusion Tensor Imaging-based ALPS index, in 44 patients with mTBI at two early post-injury time points: approximately 14 days (14Day) and 6-12 months (6-12Mon) post-injury, while also examining their associations with post-concussion symptoms. Additionally, 37 controls, comprising both orthopedic patients and healthy individuals, were included for comparative analysis. Our key findings include: 1) White matter ePVS burden (WM-ePVS) and ALPS index exhibit significant correlations with age. 2) Elevated WM-ePVS burden in acute mTBI (14Day) is significantly linked to a higher number of post-concussion symptoms, particularly memory problems. 3) The increase in the ALPS index from acute (14Day) to the chronic (6-12Mon) phases in mTBI patients correlates with improvement in sleep measures. Furthermore, incorporating WM-ePVS burden and the ALPS index from acute phase enhances the prediction of chronic memory problems beyond socio-demographic and basic clinical information, highlighting their distinct roles in assessing glymphatic structure and activity. Early evaluation of glymphatic function could be crucial for understanding TBI recovery and developing targeted interventions to improve patient outcomes.
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Affiliation(s)
- Jiachen Zhuo
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Prashant Raghavan
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Li Jiang
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Steven Roys
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Rosy Linda Njonkou Tchoquessi
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Hegang Chen
- Department of Epidemiology & public Health, University of Maryland School of Medicine, Baltimore, MD
| | - Emerson M. Wickwire
- Department of Psychiatry & Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Gunjan Y. Parikh
- Program in Trauma, University of Maryland School of Medicine, Baltimore, MD
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD
| | - Gary T. Schwartzbauer
- Program in Trauma, University of Maryland School of Medicine, Baltimore, MD
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD
| | - Lynn M. Grattan
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD
| | - Ze Wang
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Rao P. Gullapalli
- Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD
| | - Neeraj Badjatia
- Program in Trauma, University of Maryland School of Medicine, Baltimore, MD
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD
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Hashim Z, Gupta M, Neyaz Z, Srivastava S, Mani V, Nath A, Khan AR. Biophysical modeling and diffusion kurtosis imaging reveal microstructural alterations in normal-appearing white-matter regions of the brain in obstructive sleep apnea. SLEEP ADVANCES : A JOURNAL OF THE SLEEP RESEARCH SOCIETY 2024; 5:zpae031. [PMID: 38903701 PMCID: PMC11187986 DOI: 10.1093/sleepadvances/zpae031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 05/17/2024] [Indexed: 06/22/2024]
Abstract
Study Objectives Studies have indicated that sleep abnormalities are a strong risk factor for developing cognitive impairment, cardiomyopathies, and neurodegenerative disorders. However, neuroimaging modalities are unable to show any consistent markers in obstructive sleep apnea (OSA) patients. We hypothesized that, compared with those of the control cohort, advanced diffusion MRI metrics could show subtle microstructural alterations in the brains of patients with OSA. Methods Sixteen newly diagnosed patients with moderate to severe OSA and 15 healthy volunteers of the same age and sex were considered healthy controls. Multishell diffusion MRI data of the brain, along with anatomical data (T1 and T2 images), were obtained on a 3T MRI system (Siemens, Germany) after a polysomnography (PSG) test for sleep abnormalities and a behavioral test battery to evaluate cognitive and executive brain functions. Diffusion MRI data were used to compute diffusion tensor imaging and diffusion kurtosis imaging (DKI) parameters along with white-matter tract integrity (WMTI) metrics for only parallel white-matter fibers. Results OSA was diagnosed when the patient's apnea-hypopnea index was ≥ 15. No significant changes in cognitive or executive functions were observed in the OSA cohort. DKI parameters can show significant microstructural alterations in the white-matter region, while the WMTI metric, the axonal-water-fraction (fp), reveals a significant decrease in OSA patients concerning the control cohort. Conclusions Advanced diffusion MRI-based microstructural alterations in the white-matter region of the brain suggest that white-matter tracts are more sensitive to OSA-induced intermittent hypoxia.
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Affiliation(s)
- Zia Hashim
- Department of Pulmonary Medicine, SGPGIMS, Lucknow, India
| | - Mansi Gupta
- Department of Pulmonary Medicine, SGPGIMS, Lucknow, India
| | - Zafar Neyaz
- Department of Radio-diagnosis, SGPGIMS, Lucknow, India
| | | | - Vinita Mani
- Department of Neurology, SGPGIMS, Lucknow, India
| | - Alok Nath
- Department of Pulmonary Medicine, SGPGIMS, Lucknow, India
| | - Ahmad Raza Khan
- Department of Advanced Spectroscopy and Imaging, CBMR, SGPGIMS Campus, Lucknow, India
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8
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Singer R, Oganezova I, Hu W, Liu L, Ding Y, de Groot HJM, Spaink HP, Alia A. Ultrahigh field diffusion magnetic resonance imaging uncovers intriguing microstructural changes in the adult zebrafish brain caused by Toll-like receptor 2 genomic deletion. NMR IN BIOMEDICINE 2024:e5170. [PMID: 38742727 DOI: 10.1002/nbm.5170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 05/16/2024]
Abstract
Toll-like receptor 2 (TLR2) belongs to the TLR protein family that plays an important role in the immune and inflammation response system. While TLR2 is predominantly expressed in immune cells, its expression has also been detected in the brain, specifically in microglia and astrocytes. Recent studies indicate that genomic deletion of TLR2 can result in impaired neurobehavioural function. It is currently not clear if the genomic deletion of TLR2 leads to any alterations in the microstructural features of the brain. In the current study, we noninvasively assess microstructural changes in the brain of TLR2-deficient (tlr2-/-) zebrafish using state-of-the art magnetic resonance imaging (MRI) methods at ultrahigh magnetic field strength (17.6 T). A significant increase in cortical thickness and an overall trend towards increased brain volumes were observed in young tlr2-/- zebrafish. An elevated T2 relaxation time and significantly reduced apparent diffusion coefficient (ADC) unveil brain-wide microstructural alterations, potentially indicative of cytotoxic oedema and astrogliosis in the tlr2-/- zebrafish. Multicomponent analysis of the ADC diffusivity signal by the phasor approach shows an increase in the slow ADC component associated with restricted diffusion. Diffusion tensor imaging and diffusion kurtosis imaging analysis revealed diminished diffusivity and enhanced kurtosis in various white matter tracks in tlr2-/- compared with control zebrafish, identifying the microstructural underpinnings associated with compromised white matter integrity and axonal degeneration. Taken together, our findings demonstrate that the genomic deletion of TLR2 results in severe alterations to the microstructural features of the zebrafish brain. This study also highlights the potential of ultrahigh field diffusion MRI techniques in discerning exceptionally fine microstructural details within the small zebrafish brain, offering potential for investigating microstructural changes in zebrafish models of various brain diseases.
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Affiliation(s)
- Rico Singer
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Ina Oganezova
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Wanbin Hu
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Li Liu
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Yi Ding
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Huub J M de Groot
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Herman P Spaink
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - A Alia
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
- Institute of Medical Physics and Biophysics, Leipzig University, Leipzig, Germany
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9
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Tang S, Xu S, Wilder D, Medina AE, Li X, Fiskum GM, Jiang L, Kakulavarapu VR, Long JB, Gullapalli RP, Sajja VS. Longitudinal Biochemical and Behavioral Alterations in a Gyrencephalic Model of Blast-Related Mild Traumatic Brain Injury. Neurotrauma Rep 2024; 5:254-266. [PMID: 38515547 PMCID: PMC10956534 DOI: 10.1089/neur.2024.0002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024] Open
Abstract
Blast-related traumatic brain injury (bTBI) is a major cause of neurological disorders in the U.S. military that can adversely impact some civilian populations as well and can lead to lifelong deficits and diminished quality of life. Among these types of injuries, the long-term sequelae are poorly understood because of variability in intensity and number of the blast exposure, as well as the range of subsequent symptoms that can overlap with those resulting from other traumatic events (e.g., post-traumatic stress disorder). Despite the valuable insights that rodent models have provided, there is a growing interest in using injury models using species with neuroanatomical features that more closely resemble the human brain. With this purpose, we established a gyrencephalic model of blast injury in ferrets, which underwent blast exposure applying conditions that closely mimic those associated with primary blast injuries to warfighters. In this study, we evaluated brain biochemical, microstructural, and behavioral profiles after blast exposure using in vivo longitudinal magnetic resonance imaging, histology, and behavioral assessments. In ferrets subjected to blast, the following alterations were found: 1) heightened impulsivity in decision making associated with pre-frontal cortex/amygdalar axis dysfunction; 2) transiently increased glutamate levels that are consistent with earlier findings during subacute stages post-TBI and may be involved in concomitant behavioral deficits; 3) abnormally high brain N-acetylaspartate levels that potentially reveal disrupted lipid synthesis and/or energy metabolism; and 4) dysfunction of pre-frontal cortex/auditory cortex signaling cascades that may reflect similar perturbations underlying secondary psychiatric disorders observed in warfighters after blast exposure.
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Affiliation(s)
- Shiyu Tang
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Donna Wilder
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Alexandre E. Medina
- Department of Pediatrics, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Xin Li
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Gary M. Fiskum
- Department of Anesthesiology, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Shock, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Li Jiang
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Venkata R. Kakulavarapu
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Joseph B. Long
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Rao P. Gullapalli
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
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10
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Liang J, Zhang X, Lin Y, Fu G, Pan J, Feng Y, Lv X. Disparate Radiation-Induced Microstructural Injuries in Whole-Brain White Matter of Patients With Nasopharyngeal Carcinoma: A Longitudinal Study Using Multishell Diffusion MRI. J Magn Reson Imaging 2024; 59:976-986. [PMID: 36929600 DOI: 10.1002/jmri.28674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 02/28/2023] [Accepted: 02/28/2023] [Indexed: 03/18/2023] Open
Abstract
BACKGROUND Evidence for prevention strategies of radiotherapy (RT)-related injury in patients with nasopharyngeal carcinoma (NPC) was lacking. Understanding the dynamic alterations in the cerebral white matter (WM) microstructure after RT may be helpful. PURPOSE To investigate the dynamic alterations in the whole brain WM microstructure in patients with NPC in the 12 months after RT using multishell diffusion MRI (MS-dMRI). STUDY TYPE Single-center longitudinal study. POPULATION A total of 28 treatment-naïve patients with pathologically confirmed NPC (age: 39.68 ± 8.93 years, 11 female) and 20 healthy controls (age: 40.65 ± 9.76 years, 7 female). FIELD STRENGTH/SEQUENCES A 3 T, MS-dMRI using a single-shot echo planar imaging sequence. ASSESSMENT MS-dMRI was acquired at baseline for the NPC patients and healthy controls, at 0-3 (acute, AC), 6 (early delayed, ED) and 12 months (late delayed, LD) after RT for the NPC patients. The mean and maximum radiation doses to the temporal lobe were acquired. The quality of images was reviewed. MS-dMRI was analyzed using tract-based spatial statistics (TBSS). The presentations of injury were defined by the findings of TBSS. STATISTICAL TESTS Chi-square, t tests, repeated ANOVA, and Spearman-rank correlation analysis were used. P < 0.05 was considered to be statistically significant. RESULTS TBSS showed two WM injuries (injuries 1 and 2). Injury 1 emerged in the ED phase in the bilateral temporal poles and persisted throughout the ED and LD phases. Injury 2 developed from the AC to ED phase in the bilateral hemisphere and partially recovered in the LD phase. In the ED and LD phases, the multiple diffusion metrics were well correlated (r > 0.5 or <-0.5) with the RT dose, especially in the WM tracts in the temporal lobes. DATA CONCLUSION Disparate WM injuries were observed in NPC patients after RT. The injuries may be primarily or secondarily induced by radiation. Injury 1 may be irreversible, while injury 2 seems to partially recover. EVIDENCE LEVEL 2. TECHNICAL EFFICACY Stage 4.
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Affiliation(s)
- Jiahui Liang
- Department of Medical Imaging, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou, China
| | - Xinyuan Zhang
- School of Biomedical Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, China
- Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, China
| | - Yuhao Lin
- School of Biomedical Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, China
- Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, China
| | - Gui Fu
- Department of Medical Imaging, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou, China
| | - Jie Pan
- Department of Medical Imaging, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou, China
| | - Yanqiu Feng
- School of Biomedical Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, China
- Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, China
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence & Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China
- Department of Radiology, Shunde Hospital, Southern Medical University (The First People's Hospital of Shunde, Foshan), Foshan, China
| | - Xiaofei Lv
- Department of Medical Imaging, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou, China
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11
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Singh S A, Ansari MN, M. Elossaily G, Vellapandian C, Prajapati B. Investigating the Potential Impact of Air Pollution on Alzheimer's Disease and the Utility of Multidimensional Imaging for Early Detection. ACS OMEGA 2024; 9:8615-8631. [PMID: 38434844 PMCID: PMC10905749 DOI: 10.1021/acsomega.3c06328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 12/25/2023] [Accepted: 01/30/2024] [Indexed: 03/05/2024]
Abstract
Pollution is ubiquitous, and much of it is anthropogenic in nature, which is a severe risk factor not only for respiratory infections or asthma sufferers but also for Alzheimer's disease, which has received a lot of attention recently. This Review aims to investigate the primary environmental risk factors and their profound impact on Alzheimer's disease. It underscores the pivotal role of multidimensional imaging in early disease identification and prevention. Conducting a comprehensive review, we delved into a plethora of literature sources available through esteemed databases, including Science Direct, Google Scholar, Scopus, Cochrane, and PubMed. Our search strategy incorporated keywords such as "Alzheimer Disease", "Alzheimer's", "Dementia", "Oxidative Stress", and "Phytotherapy" in conjunction with "Criteria Pollutants", "Imaging", "Pathology", and "Particulate Matter". Alzheimer's disease is not only a result of complex biological factors but is exacerbated by the infiltration of airborne particles and gases that surreptitiously breach the nasal defenses to traverse the brain, akin to a Trojan horse. Various imaging modalities and noninvasive techniques have been harnessed to identify disease progression in its incipient stages. However, each imaging approach possesses inherent limitations, prompting exploration of a unified technique under a single umbrella. Multidimensional imaging stands as the linchpin for detecting and forestalling the relentless march of Alzheimer's disease. Given the intricate etiology of the condition, identifying a prospective candidate for Alzheimer's disease may take decades, rendering the development of a multimodal imaging technique an imperative. This research underscores the pressing need to recognize the chronic ramifications of invisible particulate matter and to advance our understanding of the insidious environmental factors that contribute to Alzheimer's disease.
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Affiliation(s)
- Ankul Singh S
- Department
of Pharmacology, SRM College of Pharmacy, SRM Institute of Science and Technology (SRMIST), Kattankulathur, Tamil Nadu 603203, India
| | - Mohd Nazam Ansari
- Department
of Pharmacology and Toxicology, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Alkharj 11942, Saudi Arabia
| | - Gehan M. Elossaily
- Department
of Basic Medical Sciences, College of Medicine, AlMaarefa University, P.O. Box 71666, Riyadh 13713, Saudi Arabia
| | - Chitra Vellapandian
- Department
of Pharmacology, SRM College of Pharmacy, SRM Institute of Science and Technology (SRMIST), Kattankulathur, Tamil Nadu 603203, India
| | - Bhupendra Prajapati
- Department
of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy,
Shree S.K. Patel College of Pharmaceutical Education and Research, Ganpat University, Gozaria Highway, Mehsana, North Gujarat 384012, India
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12
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Fouto AR, Henriques RN, Golub M, Freitas AC, Ruiz-Tagle A, Esteves I, Gil-Gouveia R, Silva NA, Vilela P, Figueiredo P, Nunes RG. Impact of truncating diffusion MRI scans on diffusional kurtosis imaging. MAGMA (NEW YORK, N.Y.) 2024:10.1007/s10334-024-01153-y. [PMID: 38393541 DOI: 10.1007/s10334-024-01153-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 01/09/2024] [Accepted: 02/07/2024] [Indexed: 02/25/2024]
Abstract
OBJECTIVE Diffusional kurtosis imaging (DKI) extends diffusion tensor imaging (DTI), characterizing non-Gaussian diffusion effects but requires longer acquisition times. To ensure the robustness of DKI parameters, data acquisition ordering should be optimized allowing for scan interruptions or shortening. Three methodologies were used to examine how reduced diffusion MRI scans impact DKI histogram-metrics: 1) the electrostatic repulsion model (OptEEM); 2) spherical codes (OptSC); 3) random (RandomTRUNC). MATERIALS AND METHODS Pre-acquired diffusion multi-shell data from 14 female healthy volunteers (29±5 years) were used to generate reordered data. For each strategy, subsets containing different amounts of the full dataset were generated. The subsampling effects were assessed on histogram-based DKI metrics from tract-based spatial statistics (TBSS) skeletonized maps. To evaluate each subsampling method on simulated data at different SNRs and the influence of subsampling on in vivo data, we used a 3-way and 2-way repeated measures ANOVA, respectively. RESULTS Simulations showed that subsampling had different effects depending on DKI parameter, with fractional anisotropy the most stable (up to 5% error) and radial kurtosis the least stable (up to 26% error). RandomTRUNC performed the worst while the others showed comparable results. Furthermore, the impact of subsampling varied across distinct histogram characteristics, the peak value the least affected (OptEEM: up to 5% error; OptSC: up to 7% error) and peak height (OptEEM: up to 8% error; OptSC: up to 11% error) the most affected. CONCLUSION The impact of truncation depends on specific histogram-based DKI metrics. The use of a strategy for optimizing the acquisition order is advisable to improve DKI robustness to exam interruptions.
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Affiliation(s)
- Ana R Fouto
- Institute for Systems and Robotics-Lisboa and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
| | | | - Marc Golub
- Institute for Systems and Robotics-Lisboa and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Andreia C Freitas
- Institute for Systems and Robotics-Lisboa and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Amparo Ruiz-Tagle
- Institute for Systems and Robotics-Lisboa and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Inês Esteves
- Institute for Systems and Robotics-Lisboa and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Raquel Gil-Gouveia
- Neurology Department, Hospital da Luz, Lisbon, Portugal
- Center for Interdisciplinary Research in Health, Universidade Católica Portuguesa, Lisbon, Portugal
| | - Nuno A Silva
- Learning Health, Hospital da Luz, Lisbon, Portugal
| | - Pedro Vilela
- Imaging Department, Hospital da Luz, Lisbon, Portugal
| | - Patrícia Figueiredo
- Institute for Systems and Robotics-Lisboa and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Rita G Nunes
- Institute for Systems and Robotics-Lisboa and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
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13
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Zhao K, Gao A, Gao E, Qi J, Chen T, Zhao G, Zhao G, Wang P, Wang W, Bai J, Zhang Y, Zhang H, Yang G, Ma X, Cheng J. Multiple diffusion metrics in differentiating solid glioma from brain inflammation. Front Neurosci 2024; 17:1320296. [PMID: 38352939 PMCID: PMC10861663 DOI: 10.3389/fnins.2023.1320296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 12/19/2023] [Indexed: 02/16/2024] Open
Abstract
Background and purpose The differential diagnosis between solid glioma and brain inflammation is necessary but sometimes difficult. We assessed the effectiveness of multiple diffusion metrics of diffusion-weighted imaging (DWI) in differentiating solid glioma from brain inflammation and compared the diagnostic performance of different DWI models. Materials and methods Participants diagnosed with either glioma or brain inflammation with a solid lesion on MRI were enrolled in this prospective study from May 2016 to April 2023. Diffusion-weighted imaging was performed using a spin-echo echo-planar imaging sequence with five b values (500, 1,000, 1,500, 2000, and 2,500 s/mm2) in 30 directions for each b value, and one b value of 0 was included. The mean values of multiple diffusion metrics based on diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI), mean apparent propagator (MAP), and neurite orientation dispersion and density imaging (NODDI) in the abnormal signal area were calculated. Comparisons between glioma and inflammation were performed. The area under the curve (AUC) of the receiver operating characteristic curve (ROC) of diffusion metrics were calculated. Results 57 patients (39 patients with glioma and 18 patients with inflammation) were finally included. MAP model, with its metric non-Gaussianity (NG), shows the greatest diagnostic performance (AUC = 0.879) for differentiation of inflammation and glioma with atypical MRI manifestation. The AUC of DKI model, with its metric mean kurtosis (MK) are comparable to NG (AUC = 0.855), followed by NODDI model with intracellular volume fraction (ICVF) (AUC = 0.825). The lowest value was obtained in DTI with mean diffusivity (MD) (AUC = 0.758). Conclusion Multiple diffusion metrics can be used in differentiation of inflammation and solid glioma. Non-Gaussianity (NG) from mean apparent propagator (MAP) model shows the greatest diagnostic performance for differentiation of inflammation and glioma.
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Affiliation(s)
- Kai Zhao
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Ankang Gao
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Eryuan Gao
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jinbo Qi
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Ting Chen
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Guohua Zhao
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Gaoyang Zhao
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Peipei Wang
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Weijian Wang
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jie Bai
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yong Zhang
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Huiting Zhang
- MR Research Collaboration, Siemens Healthineers Ltd., Wuhan, China
| | - Guang Yang
- Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai, China
| | - Xiaoyue Ma
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jingliang Cheng
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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14
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Kang K, Fleming K, Sathe A, Muller J, Harrop J, Middleton D, Heller J, Sharan A, Mohamed F, Krisa L, Alizadeh M. Microstructural alterations of major thalamic nuclei in the chronic pediatric spinal cord injured population. World Neurosurg X 2024; 21:100268. [PMID: 38187507 PMCID: PMC10767188 DOI: 10.1016/j.wnsx.2023.100268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 07/12/2023] [Accepted: 11/28/2023] [Indexed: 01/09/2024] Open
Abstract
Background The brain undergoes reorganization following spinal cord injury (SCI), but little is known about how the thalamus is affected in pediatric SCIs. Purpose To characterize microstructural alterations in the thalamus after SCI with diffusion tensor imaging (DTI) metrics. Methods 18 pediatric participants with chronic SCI (8-20 years) were stratified using the American Spinal Injury Association Impairment Scale (AIS) into groups: A, B, and C/D. DTI of the brain used a 3 T Siemens Verio MRI using the parameters: 20 directions, number of averages = 3, b = 1000 s/mm2, voxel size = 1.8 mm × 1.8 mm, slice thickness = 5 mm, TE = 95 ms, TR = 4300 ms, 30 slices, FOV = 230 × 230 mm2, matrix = 128 × 128, acquisition time = 4:45 min. Diffusion data was processed to generate DTI metrics FA, MD, AD, and RD. Data analysis DTI metrics were acquired by superimposing the AAL3 thalamic atlas onto participant diffusion images registered to MNI152 space. We utilized a multiple Mann-Whitney U-test to compare between AIS groups, considering values of p ≤ 0.05 as significant. Results FA, AD, RD, and MD significantly differed in thalamic nuclei between AIS groups A vs B and B vs C/D. Significant nuclei include the right ventral anterior, left intralaminar, bilateral lateral pulvinar, and right lateral geniculate. Conclusion Our findings suggest the presence of microstructural alterations based on SCI severity in pediatric patients. These results are encouraging and warrant further study.
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Affiliation(s)
- K. Kang
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, 909 Walnut St., Philadelphia, PA, 19107, USA
| | - K. Fleming
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, 909 Walnut St., Philadelphia, PA, 19107, USA
| | - A. Sathe
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, 909 Walnut St., Philadelphia, PA, 19107, USA
| | - J. Muller
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, 909 Walnut St., Philadelphia, PA, 19107, USA
| | - J. Harrop
- Department of Neurosurgery, Thomas Jefferson University, 909 Walnut Street, 2nd Floor, Philadelphia, PA, 19107, USA
| | - D. Middleton
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, 909 Walnut St., Philadelphia, PA, 19107, USA
| | - J.E. Heller
- Department of Neurosurgery, Thomas Jefferson University, 909 Walnut Street, 2nd Floor, Philadelphia, PA, 19107, USA
| | - A. Sharan
- Department of Neurosurgery, Thomas Jefferson University, 909 Walnut Street, 2nd Floor, Philadelphia, PA, 19107, USA
| | - F. Mohamed
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, 909 Walnut St., Philadelphia, PA, 19107, USA
| | - L. Krisa
- Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, 909 Walnut St., Philadelphia, PA, 19107, USA
| | - M. Alizadeh
- Department of Neurosurgery, Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, 909 Walnut St., Philadelphia, PA, 19107, USA
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15
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Gallagher RL, Koscik RL, Moody JF, Vogt NM, Adluru N, Kecskemeti SR, Van Hulle CA, Chin NA, Asthana S, Kollmorgen G, Suridjan I, Carlsson CM, Johnson SC, Dean DC, Zetterberg H, Blennow K, Alexander AL, Bendlin BB. Neuroimaging of tissue microstructure as a marker of neurodegeneration in the AT(N) framework: defining abnormal neurodegeneration and improving prediction of clinical status. Alzheimers Res Ther 2023; 15:180. [PMID: 37848950 PMCID: PMC10583332 DOI: 10.1186/s13195-023-01281-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 07/27/2023] [Indexed: 10/19/2023]
Abstract
BACKGROUND Alzheimer's disease involves accumulating amyloid (A) and tau (T) pathology, and progressive neurodegeneration (N), leading to the development of the AD clinical syndrome. While several markers of N have been proposed, efforts to define normal vs. abnormal neurodegeneration based on neuroimaging have been limited. Sensitive markers that may account for or predict cognitive dysfunction for individuals in early disease stages are critical. METHODS Participants (n = 296) defined on A and T status and spanning the AD-clinical continuum underwent multi-shell diffusion-weighted magnetic resonance imaging to generate Neurite Orientation Dispersion and Density Imaging (NODDI) metrics, which were tested as markers of N. To better define N, we developed age- and sex-adjusted robust z-score values to quantify normal and AD-associated (abnormal) neurodegeneration in both cortical gray matter and subcortical white matter regions of interest. We used general logistic regression with receiver operating characteristic (ROC) and area under the curve (AUC) analysis to test whether NODDI metrics improved diagnostic accuracy compared to models that only relied on cerebrospinal fluid (CSF) A and T status (alone and in combination). RESULTS Using internal robust norms, we found that NODDI metrics correlate with worsening cognitive status and that NODDI captures early, AD neurodegenerative pathology in the gray matter of cognitively unimpaired, but A/T biomarker-positive, individuals. NODDI metrics utilized together with A and T status improved diagnostic prediction accuracy of AD clinical status, compared with models using CSF A and T status alone. CONCLUSION Using a robust norms approach, we show that abnormal AD-related neurodegeneration can be detected among cognitively unimpaired individuals. Metrics derived from diffusion-weighted imaging are potential sensitive markers of N and could be considered for trial enrichment and as outcomes in clinical trials. However, given the small sample sizes, the exploratory nature of the work must be acknowledged.
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Affiliation(s)
- Rigina L Gallagher
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Medical Scientist Training Program, University of Wisconsin-Madison, Madison, WI, USA
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
| | - Rebecca Langhough Koscik
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
- Wisconsin Alzheimer's Institute, Madison, WI, USA
| | - Jason F Moody
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
- Wisconsin Alzheimer's Institute, Madison, WI, USA
| | - Nicholas M Vogt
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Medical Scientist Training Program, University of Wisconsin-Madison, Madison, WI, USA
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
| | - Nagesh Adluru
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
- Waisman Research Center, Madison, WI, USA
| | | | - Carol A Van Hulle
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
| | - Nathaniel A Chin
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
| | - Sanjay Asthana
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
- Veterans Administration, Madison, WI, USA
| | | | | | - Cynthia M Carlsson
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
- Wisconsin Alzheimer's Institute, Madison, WI, USA
- Veterans Administration, Madison, WI, USA
| | - Sterling C Johnson
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
- Wisconsin Alzheimer's Institute, Madison, WI, USA
- Veterans Administration, Madison, WI, USA
| | - Douglas C Dean
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Waisman Research Center, Madison, WI, USA
| | - Henrik Zetterberg
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Andrew L Alexander
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
- Waisman Research Center, Madison, WI, USA
| | - Barbara B Bendlin
- School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA.
- Wisconsin Alzheimer's Disease Research Center, Madison, WI, USA.
- Wisconsin Alzheimer's Institute, Madison, WI, USA.
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16
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Xie X, Feng M, Rong Y, Hu J, Zhou W, Li Y, Liao H, Shi L, He H, Tong Q, Sun X. Whole brain atlas-based diffusion kurtosis imaging parameters for the evaluation of multiple cognitive-related brain microstructure injuries after radiotherapy in lung cancer patients with brain metastasis. Quant Imaging Med Surg 2023; 13:5321-5332. [PMID: 37581082 PMCID: PMC10423383 DOI: 10.21037/qims-22-1376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Accepted: 06/06/2023] [Indexed: 08/16/2023]
Abstract
Background Whole brain radiation therapy (WBRT) can cause cognitive dysfunctions in lung cancer patients with brain metastasis (BM). Diffusion kurtosis imaging (DKI) can detect brain microstructural alterations sensitivly. We aimed to identify the potential of DKI parameters for early radiation-induced brain injury and investigate the association between microstructure changes and neurocognitive function (NCF) decline. Methods Lung cancer patients with BM (n=35) who underwent WBRT in a single center in Zhejiang, China, were consecutively and prospectively enrolled between June 24th, 2020 and December 22nd, 2021, and the median follow-up time was 6.0 months (3.6-6.6 months). DKI and T1-weighted (T1W) MRI scans were acquired prior to and following WBRT. Diffusivity-based (mean diffusivity, MD; fractional anisotropy, FA) and kurtosis-based (mean kurtosis, MK; axial kurtosis, AK) parameters were calculated within the automated anatomical labeling (AAL) atlas-based regions. Reliable change indices practice effects (RCI-PE) scores of the Mini-Mental State Examination (MMSE) were calculated to determine significant neurocognitive decline by a one-sample t-test from baseline to 2-6 months post-WBRT. To assess the subacute induced effects within the whole brain, percentage changes of DKI parameters were evaluated at 170 atlas-based regions by a one-sample t-test. Linear regression analyses were used to evaluate the association between DKI parameter changes and RCI-PE scores. Results Finally, the study included 19 patients in the longitudinal follow-up. RCI-PE scores declined at 2-6 months post-WBRT (mean RCI-PE =-0.842, 95% CI, -0.376 to -1.310; P=0.002). With the atlas-based analysis of subacute effects after post-WBRT, a total of 28 regions changed in at least one diffusion parameter, revealing region-wise microstructural alterations in the brain. Significant correlations of at least one diffusion parameters with RCI-PEs were observed in 9 regions, such as the right orbital part of the inferior frontal gyrus [right IFGorb, r(AK) =0.47, P=0.03] and left middle temporal gyrus [left MTG, r(MK) =-0.49, P=0.03]. Conclusions DKI parameters can be used to detect early microstructure changes and represent important imaging predictors for cognitive decline. The reported 9 regions are more particularly vulnerable to neurocognitive radiation-induced impairment for lung cancer patients with BM, representing potential dose-avoidance targets for cognitive function preservation.
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Affiliation(s)
- Xuyun Xie
- Department of Radiation Oncology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Min Feng
- Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, China
| | - Yi Rong
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, AZ, USA
| | - Jiamiao Hu
- Department of Radiation Oncology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Weiwen Zhou
- Department of Radiation Oncology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Ying Li
- Department of Nursing, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Hailong Liao
- Department of Radiation Oncology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Liming Shi
- Department of Radiation Oncology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Hongjian He
- Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, China
| | - Qiqi Tong
- Research Center for Healthcare Data Science, Zhejiang Lab, Hangzhou, China
| | - Xiaonan Sun
- Department of Radiation Oncology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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17
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Pizarro-Galleguillos BM, Kunert L, Brüggemann N, Prasuhn J. Neuroinflammation and Mitochondrial Dysfunction in Parkinson's Disease: Connecting Neuroimaging with Pathophysiology. Antioxidants (Basel) 2023; 12:1411. [PMID: 37507950 PMCID: PMC10375976 DOI: 10.3390/antiox12071411] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/07/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
There is a pressing need for disease-modifying therapies in patients suffering from neurodegenerative diseases, including Parkinson's disease (PD). However, these disorders face unique challenges in clinical trial designs to assess the neuroprotective properties of potential drug candidates. One of these challenges relates to the often unknown individual disease mechanisms that would, however, be relevant for targeted treatment strategies. Neuroinflammation and mitochondrial dysfunction are two proposed pathophysiological hallmarks and are considered to be highly interconnected in PD. Innovative neuroimaging methods can potentially help to gain deeper insights into one's predominant disease mechanisms, can facilitate patient stratification in clinical trials, and could potentially map treatment responses. This review aims to highlight the role of neuroinflammation and mitochondrial dysfunction in patients with PD (PwPD). We will specifically introduce different neuroimaging modalities, their respective technical hurdles and challenges, and their implementation into clinical practice. We will gather preliminary evidence for their potential use in PD research and discuss opportunities for future clinical trials.
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Affiliation(s)
- Benjamin Matís Pizarro-Galleguillos
- Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile
- Department of Neurology, University Medical Center Schleswig-Holstein, Campus Lübeck, 23562 Lübeck, Germany
- Institute of Neurogenetics, University of Lübeck, 23562 Lübeck, Germany
- Center for Brain, Behavior, and Metabolism, University of Lübeck, 23562 Lübeck, Germany
| | - Liesa Kunert
- Department of Neurology, University Medical Center Schleswig-Holstein, Campus Lübeck, 23562 Lübeck, Germany
- Institute of Neurogenetics, University of Lübeck, 23562 Lübeck, Germany
- Center for Brain, Behavior, and Metabolism, University of Lübeck, 23562 Lübeck, Germany
| | - Norbert Brüggemann
- Department of Neurology, University Medical Center Schleswig-Holstein, Campus Lübeck, 23562 Lübeck, Germany
- Center for Brain, Behavior, and Metabolism, University of Lübeck, 23562 Lübeck, Germany
| | - Jannik Prasuhn
- Department of Neurology, University Medical Center Schleswig-Holstein, Campus Lübeck, 23562 Lübeck, Germany
- Institute of Neurogenetics, University of Lübeck, 23562 Lübeck, Germany
- Center for Brain, Behavior, and Metabolism, University of Lübeck, 23562 Lübeck, Germany
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21287, USA
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18
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Zhong Y, Guan J, Ma Y, Xu M, Cheng Y, Xu L, Lin Y, Zhang X, Wu R. Role of Imaging Modalities and N-Acetylcysteine Treatment in Sepsis-Associated Encephalopathy. ACS Chem Neurosci 2023; 14:2172-2182. [PMID: 37216423 PMCID: PMC10252850 DOI: 10.1021/acschemneuro.3c00180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 05/04/2023] [Indexed: 05/24/2023] Open
Abstract
Sepsis-associated encephalopathy is a severe systemic infection complication. Although early stages involve pathophysiological changes, detection using conventional imaging is challenging. Glutamate chemical exchange saturation transfer and diffusion kurtosis imaging can noninvasively investigate cellular and molecular events in early disease stages using magnetic resonance imaging (MRI). N-Acetylcysteine, an antioxidant and precursor of glutathione, regulates neurotransmitter glutamate metabolism and participates in neuroinflammation. We investigated the protective role of n-acetylcysteine in sepsis-associated encephalopathy using a rat model and monitored changes in brain using magnetic resonance (MR) molecular imaging. Bacterial lipopolysaccharide was injected intraperitoneally to induce a sepsis-associated encephalopathy model. Behavioral performance was assessed using the open-field test. Tumor necrosis factor α and glutathione levels were detected biochemically. Imaging was performed using a 7.0-T MRI scanner. Protein expression, cellular damage, and changes in blood-brain barrier permeability were assessed using western blotting, pathological staining, and Evans blue staining, respectively. Lipopolysaccharide-induced rats showed reduced anxiety and depression after treatment with n-acetylcysteine. MR molecular imaging can identify pathological processes at different disease stages. Furthermore, rats treated with n-acetylcysteine showed increased glutathione levels and decreased tumor necrosis factor α, suggesting enhanced antioxidant capacity and inhibition of inflammatory processes, respectively. Western blot analysis showed reduced expression of nuclear factor kappa B (p50) protein after treatment, suggesting that n-acetylcysteine inhibits inflammation via this signaling pathway. Finally, n-acetylcysteine-treated rats showed reduced cellular damage by pathology and reduced extravasation of their blood-brain barrier by Evans Blue staining. Thus, n-acetylcysteine might be a therapeutic option for sepsis-associated encephalopathy and other neuroinflammatory diseases. Furthermore, noninvasive "dynamic visual monitoring" of physiological and pathological changes related to sepsis-associated encephalopathy was achieved using MR molecular imaging for the first time, providing a more sensitive imaging basis for early diagnosis, identification, and prognosis.
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Affiliation(s)
- Yazhi Zhong
- Department
of Radiology, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
- Department
of Radiology, Huizhou Central People’s
Hospital, Huizhou 516001 Guangdong, China
| | - Jitian Guan
- Department
of Radiology, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
| | - Yunfeng Ma
- Department
of Emergency, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
| | - Meiling Xu
- Department
of Emergency, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
| | - Yan Cheng
- Department
of Radiology, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
- Department
of Radiology, The Second Hospital of Shandong
University, Jinan 250033 Shandong, China
| | - Liang Xu
- Department
of Radiology, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
- Department
of Radiology, The Seventh Affiliated Hospital,
Sun Yat-sen University, Shenzhen 518100 Guangdong, China
| | - Yan Lin
- Department
of Radiology, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
| | - Xiaolei Zhang
- Department
of Radiology, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
| | - Renhua Wu
- Department
of Radiology, The Second Affiliated Hospital,
Shantou University Medical College, Shantou 515041 Guangdong, China
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19
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Yadikar H, Johnson C, Pafundi N, Nguyen L, Kurup M, Torres I, Al-Enezy A, Yang Z, Yost R, Kobeissy FH, Wang KKW. Neurobiochemical, Peptidomic, and Bioinformatic Approaches to Characterize Tauopathy Peptidome Biomarker Candidates in Experimental Mouse Model of Traumatic Brain Injury. Mol Neurobiol 2023; 60:2295-2319. [PMID: 36635478 DOI: 10.1007/s12035-022-03165-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 12/10/2022] [Indexed: 01/14/2023]
Abstract
Traumatic brain injury (TBI) is a multidimensional damage, and currently, no FDA-approved medicine is available. Multiple pathways in the cell are triggered through a head injury (e.g., calpain and caspase activation), which truncate tau and generate variable fragment sizes (MW 400-45,000 K). In this study, we used an open-head TBI mouse model generated by controlled cortical impact (CCI) and collected ipsilateral (IC) and contralateral (CC) mice htau brain cortices at one (D1) three (D3), and seven (D7) days post-injury. We implemented immunological (antibody-based detection) and peptidomic approaches (nano-reversed-phase liquid chromatography/tandem mass spectrometry) to investigate proteolytic tau peptidome (low molecular weight (LMW) < 10 K)) and pathological phosphorylation sites (high-molecular-weight (HMW); > 10 K) derived from CCI-TBI animal models. Our immunoblotting analysis verified tau hyperphosphorylation, HMW, and HMW breakdown products (HMW-BDP) formation of tau (e.g., pSer202, pThr181, pThr231, pSer396, and pSer404), following CCI-TBI. Peptidomic data revealed unique sequences of injury-dependent proteolytic peptides generated from human tau protein. Among the N-terminal tau peptides, EIPEGTTAEEAGIGDTPSLEDEAAGHVTQA (a.a. 96-125) and AQPHTEIPEGTTAEEAGIGDTPSLEDEAAGHVTQARM (a.a. 91-127). Examples of tau C-terminal peptides identified include NVSSTGSIDMVDSPQLATLADEVSASLAKQGL (a.a. 410-441) and QLATLADEVSASLAKQGL (a.a. 424-441). Our peptidomic bioinformatic tools showed the association of proteases, such as CAPN1, CAPN2, and CTSL; CASP1, MMP7, and MMP9; and ELANE, GZMA, and MEP1A, in CCI-TBI tau peptidome. In clinical trials for novel TBI treatments, it might be useful to monitor a subset of tau peptidome as targets for biomarker utility and use them for a "theranostic" approach.
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Affiliation(s)
- Hamad Yadikar
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait.
| | - Connor Johnson
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Niko Pafundi
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Lynn Nguyen
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Milin Kurup
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Isabel Torres
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Albandery Al-Enezy
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Zhihui Yang
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait, Kuwait
| | - Richard Yost
- Department of Chemistry, Chemistry Laboratory Building, University of Florida, Gainesville, FL, 32611, USA
| | - Firas H Kobeissy
- Program for Neurotrauma, Neuroproteomics & Biomarkers Research, Departments of Emergency Medicine, Psychiatry, Neuroscience and Chemistry, University of Florida, Gainesville, FL, USA. .,Department of Biochemistry and Molecular Genetics, American University of Beirut, Beirut, Lebanon. .,Morehouse School of Medicine, Department of Neurobiology, Center for Neurotrauma, Multiomics & Biomarkers (CNMB), 720 Westview Dr. SW, Atlanta, GA, 30310, USA.
| | - Kevin K W Wang
- Program for Neurotrauma, Neuroproteomics & Biomarkers Research, Departments of Emergency Medicine, Psychiatry, Neuroscience and Chemistry, University of Florida, Gainesville, FL, USA. .,Morehouse School of Medicine, Department of Neurobiology, Center for Neurotrauma, Multiomics & Biomarkers (CNMB), 720 Westview Dr. SW, Atlanta, GA, 30310, USA. .,Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, FL, 32608, USA.
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20
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Diffusion-Weighted Imaging in Mild Traumatic Brain Injury: A Systematic Review of the Literature. Neuropsychol Rev 2023; 33:42-121. [PMID: 33721207 DOI: 10.1007/s11065-021-09485-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 02/09/2021] [Indexed: 12/14/2022]
Abstract
There is evidence that diffusion-weighted imaging (DWI) is able to detect tissue alterations following mild traumatic brain injury (mTBI) that may not be observed on conventional neuroimaging; however, findings are often inconsistent between studies. This systematic review assesses patterns of differences in DWI metrics between those with and without a history of mTBI. A PubMed literature search was performed using relevant indexing terms for articles published prior to May 14, 2020. Findings were limited to human studies using DWI in mTBI. Articles were excluded if they were not full-length, did not contain original data, if they were case studies, pertained to military populations, had inadequate injury severity classification, or did not report post-injury interval. Findings were reported independently for four subgroups: acute/subacute pediatric mTBI, acute/subacute adult mTBI, chronic adult mTBI, and sport-related concussion, and all DWI acquisition and analysis methods used were included. Patterns of findings between studies were reported, along with strengths and weaknesses of the current state of the literature. Although heterogeneity of sample characteristics and study methods limited the consistency of findings, alterations in DWI metrics were most commonly reported in the corpus callosum, corona radiata, internal capsule, and long association pathways. Many acute/subacute pediatric studies reported higher FA and lower ADC or MD in various regions. In contrast, acute/subacute adult studies most commonly indicate lower FA within the context of higher MD and RD. In the chronic phase of recovery, FA may remain low, possibly indicating overall demyelination or Wallerian degeneration over time. Longitudinal studies, though limited, generally indicate at least a partial normalization of DWI metrics over time, which is often associated with functional improvement. We conclude that DWI is able to detect structural mTBI-related abnormalities that may persist over time, although future DWI research will benefit from larger samples, improved data analysis methods, standardized reporting, and increasing transparency.
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21
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Lee D, Lee Y, Lee Y, Kim K. Functional Connectivity in the Mouse Brainstem Represents Signs of Recovery from Concussion. J Neurotrauma 2023; 40:240-249. [PMID: 36103389 DOI: 10.1089/neu.2022.0126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Mild traumatic brain injury (mTBI) is one of the most frequent neurological disorders. Diagnostic criteria for mTBI are based on cognitive or neurological symptoms without fully understanding the neuropathological basis for explaining behaviors. From the neuropathological perspective of mTBI, recent neuroimaging studies have focused on structural or functional differences in motor-related cortical regions but did not compare topological network properties between the post-concussion days in the brainstem. We investigated temporal changes in functional connectivity and evaluated network properties of functional networks in the mouse brainstem. We observed a significantly decreased functional connectivity and global and local network properties on post-concussion day 7, which normalized on post-concussion day 14. Functional connectivity and local network properties on post-concussion day 2 were also significantly decreased compared with those on post-concussion day 14, but there were no significant group differences in global network properties between days 2 and 14. We also observed that the local efficiency and clustering coefficient of the brainstem network were significantly correlated with anxiety-like behaviors on post-concussion days 7 and 14. This study suggests that functional connectivity in the mouse brainstem provides vital recovery signs from concussion through functional reorganization.
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Affiliation(s)
- Dongha Lee
- Cognitive Science Research Group and Korea Brain Research Institute, Daegu, Republic of Korea
| | - Yujeong Lee
- Cognitive Science Research Group and Korea Brain Research Institute, Daegu, Republic of Korea
| | - Yoonsang Lee
- Cognitive Science Research Group and Korea Brain Research Institute, Daegu, Republic of Korea
| | - Kipom Kim
- Research Strategy Office, Korea Brain Research Institute, Daegu, Republic of Korea
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22
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Zhong Y, Guan J, Ma Y, Xu M, Cheng Y, Xu L, Lin Y, Zhang X, wu R. Role of imaging modalities and N-acetylcysteine treatment in sepsis-associated encephalopathy.. [DOI: 10.21203/rs.3.rs-2459747/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Abstract
Background
Sepsis-associated encephalopathy is a severe complication due to systemic infection. Although early stages involve pathophysiological changes, detection using conventional imaging is challenging. Glutamate chemical exchange saturation transfer and diffusion kurtosis imaging can noninvasively investigate cellular and molecular events in the early stage of the disease by MRI. N-acetylcysteine, an antioxidant and precursor of glutathione, regulates the metabolism of the neurotransmitter glutamate and participates in neuroinflammation. We aimed to investigate the protective role of n-acetylcysteine in sepsis-associated encephalopathy using a rat model and monitor changes in the brain using magnetic resonance molecular imaging.
Methods
Bacterial lipopolysaccharide was injected intraperitoneally into the rats to induce a sepsis-associated encephalopathy model. The behavioural performance was assessed using the open field test. Tumour necrosis factor alpha and glutathione levels were detected biochemically. Imaging was performed using a 7.0-T MRI scanner. Protein expressions and cellular damage were assessed by western blotting and pathological staining, respectively. We also evaluated changes in the blood-brain barrier permeability by the Evans blue staining.
Results
The lipopolysaccharide-induced rats showed reduced anxiety and depression after treatment with n-acetylcysteine. Magnetic resonance molecular imaging can identify pathological processes at different stages of the disease. Furthermore, rats treated with n-acetylcysteine showed increased glutathione levels and decreased tumour necrosis factor alpha, suggesting enhanced antioxidant capacity and inhibition of inflammatory processes, respectively. Western blot analysis showed a reduced expression of nuclear factor kappa B (p50) protein after treatment, suggesting that n-acetylcysteine inhibits inflammation via this signalling pathway. Finally, n-acetylcysteine treated rats also showed reduced cellular damage by pathology and reduced extravasation of their blood-brain barrier by Evan Blue staining.
Conclusion
This study showed that n-acetylcysteine might be a therapeutic option for sepsis-associated encephalopathy and other neuroinflammatory diseases. Furthermore, non-invasive ‘dynamic visual monitoring’ of the physiological and pathological changes related to sepsis-associated encephalopathy was achieved for the first time using magnetic resonance molecular imaging, which provides a more sensitive imaging basis for early clinical diagnosis, identification, and prognosis.
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Affiliation(s)
| | - Jitian Guan
- Second Affiliated Hospital of Shantou University Medical College
| | - Yunfeng Ma
- Second Affiliated Hospital of Shantou University Medical College
| | - Meiling Xu
- Second Affiliated Hospital of Shantou University Medical College
| | - Yan Cheng
- Second Affiliated Hospital of Shantou University Medical College
| | - Liang Xu
- The Seventh Affiliated Hospital of Sun Yat-sen University
| | - Yan Lin
- The Second Hospital of Shandong University
| | - Xiaolei Zhang
- Second Affiliated Hospital of Shantou University Medical College
| | - renhua wu
- Second Affiliated Hospital of Shantou University Medical College
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23
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Welton T, Hartono S, Shih YC, Lee W, Chai PH, Chong SL, Ng SYE, Chia NSY, Choi X, Heng DL, Tan EK, Tan LCS, Chan LL. Microstructure of Brain Nuclei in Early Parkinson's Disease: Longitudinal Diffusion Kurtosis Imaging. JOURNAL OF PARKINSON'S DISEASE 2023; 13:233-242. [PMID: 36744346 PMCID: PMC10041414 DOI: 10.3233/jpd-225095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Diffusion kurtosis imaging provides in vivo measurement of microstructural tissue characteristics and could help guide management of Parkinson's disease. OBJECTIVE To investigate longitudinal diffusion kurtosis imaging changes on magnetic resonance imaging in the deep grey nuclei in people with early Parkinson's disease over two years, and whether they correlate with disease progression. METHODS We conducted a longitudinal case-control study of early Parkinson's disease. 262 people (Parkinson's disease: n = 185, aged 67.5±9.1 years; 43% female; healthy controls: n = 77, aged 66.6±8.1 years; 53% female) underwent diffusion kurtosis imaging and clinical assessment at baseline and two-year timepoints. We automatically segmented five nuclei, comparing the mean kurtosis and other diffusion kurtosis imaging indices between groups and over time using repeated-measures analysis of variance, and Pearson correlation with the two-year change in Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III. RESULTS At baseline, mean kurtosis was higher in Parkinson's disease than controls in the substantia nigra, putamen, thalamus and globus pallidus when adjusting for age, sex, and levodopa equivalent daily dose (p < 0.027). These differences grew over two years, with mean kurtosis increasing for the Parkinson's disease group while remaining stable for the control group; evident in significant "group ×time" interaction effects for the putamen, thalamus and globus pallidus (ηp2= 0.08-0.11, p < 0.015). However, we did not detect significant correlations between increasing mean kurtosis and declining motor function in the Parkinson's disease group. CONCLUSION Diffusion kurtosis imaging of specific grey matter structures shows abnormal microstructure in PD at baseline and abnormal progression in PD over two years.
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Affiliation(s)
- Thomas Welton
- Department of Neurology, National Neuroscience Institute, Tan Tock Seng Hospital, Singapore
- Neuroscience Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - Septian Hartono
- Department of Neurology, National Neuroscience Institute, Tan Tock Seng Hospital, Singapore
- Neuroscience Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - Yao-Chia Shih
- Neuroscience Academic Clinical Program, Duke-NUS Medical School, Singapore
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
- Graduate Institute of Medicine, Yuan Ze University, Taoyuan City, Taiwan
| | - Weiling Lee
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
| | - Pik Hsien Chai
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
| | - Say Lee Chong
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
| | - Samuel Yong Ern Ng
- Department of Neurology, National Neuroscience Institute, Tan Tock Seng Hospital, Singapore
| | - Nicole Shuang Yu Chia
- Department of Neurology, National Neuroscience Institute, Tan Tock Seng Hospital, Singapore
| | - Xinyi Choi
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
| | - Dede Liana Heng
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
| | - Eng-King Tan
- Department of Neurology, National Neuroscience Institute, Tan Tock Seng Hospital, Singapore
- Neuroscience Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - Louis C S Tan
- Department of Neurology, National Neuroscience Institute, Tan Tock Seng Hospital, Singapore
- Neuroscience Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - Ling-Ling Chan
- Neuroscience Academic Clinical Program, Duke-NUS Medical School, Singapore
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
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24
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Liu X, Zhang Y, Chen F, Wang L, Luo W, Zheng Y, Yan G. Preliminary research of the classification of the brain acute stroke lesions by the Diffusion Kurtosis Imaging (DKI) and Diffusion Weighted Imaging (DWI) parameters. Technol Health Care 2023; 31:525-532. [PMID: 37066948 PMCID: PMC10258876 DOI: 10.3233/thc-236046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
BACKGROUND Diffusion-weighted magnetic resonance imaging (DWI) is a mature scanning technique. With high sensitivity in detecting cerebral infractions, it has become an essential part of the clinical evaluation of acute stroke. However, with the update in medical ideals and treatment, clinicians are now focusing on distinguishing between reversible and irreversible brain tissue damage rather than detecting ischaemic lesions alone. OBJECTIVE We supposed that Diffusion Kurtosis Imaging (DKI) could classify heterogeneous DWI lesions, deepening the understanding of tissue injury. We systematically studied the different parameters of DKI in acute stroke patients in the literature. METHODS We collected 41 patients (26 male, 15 female), including different infarctions with acute cerebral infarction in different brain regions. Of all patients, 20 were single-infarction, while others were multi-infarctions. In this paper, we categorized acute cerebral infarction lesions into two types according to the parametric characteristics of both DKI and DWI. Type I means the DKI and DWI were matched, and Type II means the DKI and DWI were mismatched. Based on each parametric map, the region of interest (ROI) is outlined in each most severe lesion area (as large as possible in the center of the lesion). In the control group, ROIs of the same size are located in the corresponding regions of the contralateral hemisphere. RESULTS In both Type I and Type II, all parameters conform to a normal distribution. An independent sample T-test was used to compare the differences between each group. In Type I, we found the FA, MD, Da, Dr, MK and Ka values were statistically different (P< 0.05), while in Type II, only the MK and Ka values were statistically different (P< 0.05). CONCLUSION DKI, compared to DWI, can provide more imaging information about intracranial ischemic infarction, which can deepen the understanding of the mechanism of ischemic tissue damage. Our classification of the brain acute stroke lesions by DKI parameters and DWI may help us rediscover the real core of infraction.
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Affiliation(s)
- Xin Liu
- Department of Radiology, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China
| | - Ying Zhang
- Department of Radiology, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China
- Department of Radiology, The Affiliated Hospital of Yanbian University, Yanbian, Jilin, China
| | - Fang Chen
- Department of Radiology, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China
| | - Lei Wang
- Department of Radiology, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China
| | - Wenbin Luo
- Department of Radiology, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China
| | - Ye Zheng
- Department of Radiology, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China
| | - Gen Yan
- Department of Radiology, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China
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San Martín Molina I, Fratini M, Campi G, Burghammer M, Grünewald TA, Salo RA, Narvaez O, Aggarwal M, Tohka J, Sierra A. A multiscale tissue assessment in a rat model of mild traumatic brain injury. J Neuropathol Exp Neurol 2022; 82:71-83. [PMID: 36331507 PMCID: PMC9764078 DOI: 10.1093/jnen/nlac100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Diffusion tensor imaging (DTI) has demonstrated the potential to assess the pathophysiology of mild traumatic brain injury (mTBI) but correlations of DTI findings and pathological changes in mTBI are unclear. We evaluated the potential of ex vivo DTI to detect tissue damage in a mild mTBI rat model by exploiting multiscale imaging methods, histology and scanning micro-X-ray diffraction (SμXRD) 35 days after sham-operation (n = 2) or mTBI (n = 3). There were changes in DTI parameters rostral to the injury site. When examined by histology and SμXRD, there was evidence of axonal damage, reduced myelin density, gliosis, and ultrastructural alterations in myelin that were ongoing at the experimental time point of 35 days postinjury. We assessed the relationship between the 3 imaging modalities by multiple linear regression analysis. In this analysis, DTI and histological parameters were moderately related, whereas SμXRD parameters correlated weakly with DTI and histology. These findings suggest that while DTI appears to distinguish tissue changes at the microstructural level related to the loss of myelinated axons and gliosis, its ability to visualize alterations in myelin ultrastructure is limited. The use of several imaging techniques represents a novel approach to reveal tissue damage and provides new insights into mTBI detection.
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Affiliation(s)
| | - Michela Fratini
- Institute of Nanotechnology-CNR c/o Physics Department, Sapienza University of Rome, Rome, Italy,IRCCS Fondazione Santa Lucia, Rome, Italy
| | | | | | - Tilman A Grünewald
- European Synchrotron Radiation Facility, Grenoble Cedex, France,Aix-Marseille Université, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France
| | - Raimo A Salo
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Omar Narvaez
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Manisha Aggarwal
- Russell H. Morgan Department of Radiology and Radiological Science, John Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jussi Tohka
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Alejandra Sierra
- Send correspondence to: Alejandra Sierra, PhD, A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland (Kuopio Campus), PO Box 1627, Neulaniementie 2, FI-70211 Kuopio, Finland; E-mail:
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Exploration of RCBF and Metabolic Changes in the Brain Functional Areas of Patients with Hypothyroidism by ASL and MRS Techniques. DISEASE MARKERS 2022; 2022:9204119. [PMID: 36277976 PMCID: PMC9586791 DOI: 10.1155/2022/9204119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 09/19/2022] [Indexed: 11/25/2022]
Abstract
Objective To study the regional cerebral blood flow (rCBF) in important brain functional areas and the metabolic levels of these brain functional areas in patients with primary hypothyroidism by using arterial spin labeling (ASL) and magnetic resonance spectroscopy (MRS) techniques to explain the possible causes of brain dysfunction in patients with primary hypothyroidism. Methods Twenty-five patients with primary hypothyroidism (newly diagnosed and not treated) who were treated in the endocrinology department of our hospital were selected as the research group, and 25 healthy patients with normal thyroid function who came to our hospital during the same period with matched gender and age were selected as the control group. ASL and MRS techniques were used to detect and calculate regional cerebral blood flow (rCBF) in the frontal lobe, hippocampus, and posterior cingulate gyrus, as well as N-acetylaspartate/creatine (NAA/Cr), choline/creatine (Cho) in the brain/Cr, and inositol/creatine (mI/Cr) ratio. The correlations between metabolite ratios measured by rCBF, MRS, and serum TSH, FT3, and FT4 levels were analyzed. Results Compared with the control group, the rCBF in the frontal lobe, hippocampus, and posterior cingulate gyrus of the dominant hemisphere of the hypothyroid patients in the study group decreased significantly (P < 0.05). The comparison of metabolite ratios showed that compared with the control group, the NAA/Cr ratio of the frontal lobe and posterior cingulate gyrus of the study group was significantly decreased, and the Cho/Cr ratio of the posterior cingulate gyrus of the study group was significantly increased. The MI/Cr ratio of the hippocampus was significantly decreased (all P values < 0.05). Correlation analysis showed that rCBF and NAA/Cr in posterior cingulate gyrus were significantly negatively correlated with serum TSH levels (P < 0.05). Conclusion The changes of rCBF and metabolite ratios in the frontal lobe, hippocampus, and posterior cingulate gyrus of patients with primary hypothyroidism can be detected using ASL and MRS techniques. The changes of rCBF and metabolite ratio and their negative correlation with serum TSH level are helpful to explain the causes of brain dysfunction in patients with primary hypothyroidism.
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27
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Plank JR, Glover SC, Moloney BD, Hoeh NR, Sundram F, Sumner RL, Muthukumaraswamy S, Lin JC. A randomized, double-blind, placebo-controlled, hybrid parallel-arm study of low-dose naltrexone as an adjunctive anti-inflammatory treatment for major depressive disorder. Trials 2022; 23:822. [PMID: 36175917 PMCID: PMC9524133 DOI: 10.1186/s13063-022-06738-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 09/13/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Major depressive disorder (MDD) is a leading cause of disability worldwide. The current treatments are ineffective in approximately one-third of patients, resulting in a large economic burden and reduced quality of life for a significant proportion of the global population. There is considerable evidence that increased inflammation may distinguish a sub-type of MDD, and there are no validated diagnostic tools or treatments for neuroinflammation in MDD patients. The current study aims to explore the potential role of low-dose naltrexone (LDN), a drug with purported anti-inflammatory properties in the central nervous system, as an adjunctive treatment in patients with MDD. METHODS/DESIGN This double-blind placebo-controlled hybrid parallel arm study enables the exploration of peripheral and central inflammatory markers with LDN as an approach to investigate inflammation as a pathophysiological contributor to MDD. Eligible participants with MDD (n = 48) will be stratified into the high and low inflammatory groups according to the levels of high-sensitivity C-reactive protein (hs-CRP) and then randomized to receive LDN or placebo for an initial 12 weeks, followed by a further 12 weeks during which all participants will receive LDN. The primary outcome measure will be the Montgomery-Åsberg Depression Rating Scale (MADRS) administered at baseline, 2 weeks, 4 weeks, 8 weeks, 12 weeks, 14 weeks, 16 weeks, 20 weeks, and 24 weeks, to assess the effectiveness of the anti-depressant response. The secondary outcomes include the use of MRI techniques including quantitative magnetization transfer (qMT), echo-planar spectroscopic imaging (EPSI), and diffusion-weighted imaging (DWI) to help to elucidate the neurobiological mechanism of LDN, and the inflammatory mechanisms in action in MDD. Electroencephalography, blood samples, cognitive tasks, and additional questionnaires will also be used to determine if there is a specific profile of symptoms in individuals with inflammatory MDD. Healthy participants (n = 24) will be recruited for baseline outcome measures only, to enable comparison with patients with MDD. DISCUSSION This trial contributes to the literature on inflammation in MDD, including the understanding of the pathophysiology and efficacy of anti-inflammatory treatments. The investigation of inflammatory mechanisms in MDD is an important first step in the development of biomarkers to classify patient sub-groups, increase the accuracy of diagnosis, and tailor the approach to patients in clinical practice. This study may provide evidence of the benefit of LDN for the groups in whom conventional anti-depressants are ineffective and lead the way for translation into clinical practice. TRIAL REGISTRATION Australian New Zealand Clinical Trials Registry ACTRN12622000881730 . Registered on 21 June 2022.
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Affiliation(s)
- Julia R Plank
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand
| | - Stephanie C Glover
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand
| | - Ben D Moloney
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand
| | - Nicholas R Hoeh
- Department of Psychological Medicine, School of Medicine, Faculty of Medical and Health Sciences, University of Auckland, 22-30 Park Avenue, Grafton, Auckland, 1023, New Zealand
| | - Frederick Sundram
- Department of Psychological Medicine, School of Medicine, Faculty of Medical and Health Sciences, University of Auckland, 22-30 Park Avenue, Grafton, Auckland, 1023, New Zealand
| | - Rachael L Sumner
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand
| | - Suresh Muthukumaraswamy
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand
| | - Joanne C Lin
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand.
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28
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Zhou H, Shang H, Li X, Tian M, Wei R. Measuring healthy female nulliparous pubovisceral muscle from diffusion kurtosis imaging. NMR IN BIOMEDICINE 2022; 35:e4753. [PMID: 35485163 DOI: 10.1002/nbm.4753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 04/27/2022] [Accepted: 04/27/2022] [Indexed: 06/14/2023]
Abstract
This study explores the feasibility of using diffusion kurtosis imaging (DKI) in the pelvic floor region and assesses the water diffusivity of the pubovisceral muscle. Twenty-seven healthy young nulliparous females underwent DKI at 3.0 T that included 15 gradient directions and three b values (0, 750, and 1500 s/mm2 ). The diffusion tensor and diffusion kurtosis metrics values of the pubovisceral muscle were measured after image processing. Two independent sample t-tests, a paired-samples t-test, and a nonparametric hypothesis test were performed as appropriate to compare the differences among different metrics. Twenty-six subjects (mean ± standard deviation age, 25 ± 2 years) were successfully analyzed by measuring the diffusion tensor and diffusion kurtosis metrics of the bilateral pubovisceral muscles. The metrics included mean kurtosis, axial kurtosis, radial kurtosis, fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity. We found no statistically significant differences for these measurement values between the left and right pubovisceral muscles (p = 0.271-0.931). However, radial kurtosis was greater than axial kurtosis in both pubovisceral muscles (p < 0.001) and axial diffusivity was lower than radial diffusivity in both pubovisceral muscles (p < 0.001). We deem the application of DKI technology to the pelvic floor region to be feasible.
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Affiliation(s)
- Huiqing Zhou
- The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Hua Shang
- The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Xiaodong Li
- The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Miaomiao Tian
- The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Rongchen Wei
- The Second Hospital of Hebei Medical University, Shijiazhuang, China
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Benjamini D, Priemer DS, Perl DP, Brody DL, Basser PJ. Mapping astrogliosis in the individual human brain using multidimensional MRI. Brain 2022; 146:1212-1226. [PMID: 35953450 PMCID: PMC9976979 DOI: 10.1093/brain/awac298] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 06/13/2022] [Accepted: 08/06/2022] [Indexed: 11/14/2022] Open
Abstract
There are currently no non-invasive imaging methods available for astrogliosis assessment or mapping in the central nervous system despite its essential role in the response to many disease states, such as infarcts, neurodegenerative conditions, traumatic brain injury and infection. Multidimensional MRI is an increasingly employed imaging modality that maximizes the amount of encoded chemical and microstructural information by probing relaxation (T1 and T2) and diffusion mechanisms simultaneously. Here, we harness the exquisite sensitivity of this imagining modality to derive a signature of astrogliosis and disentangle it from normative brain at the individual level using machine learning. We investigated ex vivo cerebral cortical tissue specimens derived from seven subjects who sustained blast-induced injuries, which resulted in scar-border forming astrogliosis without being accompanied by other types of neuropathological abnormality, and from seven control brain donors. By performing a combined post-mortem radiology and histopathology correlation study we found that astrogliosis induces microstructural and chemical changes that are robustly detected with multidimensional MRI, and which can be attributed to astrogliosis because no axonal damage, demyelination or tauopathy were histologically observed in any of the cases in the study. Importantly, we showed that no one-dimensional T1, T2 or diffusion MRI measurement can disentangle the microscopic alterations caused by this neuropathology. Based on these findings, we developed a within-subject anomaly detection procedure that generates MRI-based astrogliosis biomarker maps ex vivo, which were significantly and strongly correlated with co-registered histological images of increased glial fibrillary acidic protein deposition (r = 0.856, P < 0.0001; r = 0.789, P < 0.0001; r = 0.793, P < 0.0001, for diffusion-T2, diffusion-T1 and T1-T2 multidimensional data sets, respectively). Our findings elucidate the underpinning of MRI signal response from astrogliosis, and the demonstrated high spatial sensitivity and specificity in detecting reactive astrocytes at the individual level, and if reproduced in vivo, will significantly impact neuroimaging studies of injury, disease, repair and aging, in which astrogliosis has so far been an invisible process radiologically.
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Affiliation(s)
- Dan Benjamini
- Correspondence to: Dan Benjamini, PhD National Institutes of Health (NIH), 251 Bayview Blvd., Baltimore, MD 21224, USA E-mail:
| | - David S Priemer
- Department of Pathology, F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, MD 20814, USA,The Department of Defense/Uniformed Services, University Brain Tissue Repository, Bethesda, MD 20814, USA,The Henry M. Jackson Foundation for the Advancement of Military Medicine (HJF), Bethesda, MD 20817, USA
| | - Daniel P Perl
- Department of Pathology, F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, MD 20814, USA,The Department of Defense/Uniformed Services, University Brain Tissue Repository, Bethesda, MD 20814, USA
| | - David L Brody
- Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA,Department of Neurology, F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, MD 20814, USA,Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD 20892, USA
| | - Peter J Basser
- Section on Quantitative Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD 20891, USA,Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
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30
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Asschenfeldt B, Evald L, Salvig C, Heiberg J, Østergaard L, Eskildsen SF, Hjortdal VE. Altered Cerebral Microstructure in Adults With Atrial Septal Defect and Ventricular Septal Defect Repaired in Childhood. J Am Heart Assoc 2022; 11:e020915. [PMID: 35699183 PMCID: PMC9238637 DOI: 10.1161/jaha.121.020915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Background Delayed brain development, brain injury, and neurodevelopmental disabilities are commonly observed in infants operated for complex congenital heart defect. Our previous findings of poorer neurodevelopmental outcomes in individuals operated for simple congenital heart defects calls for further etiological clarification. Hence, we examined the microstructural tissue composition in cerebral cortex and subcortical structures in comparison to healthy controls and whether differences were associated with neurodevelopmental outcomes. Methods and Results Adults (n=62) who underwent surgical closure of an atrial septal defect (n=33) or a ventricular septal defect (n=29) in childhood and a group of healthy, matched controls (n=38) were enrolled. Brain diffusional kurtosis imaging and neuropsychological assessment were performed. Cortical and subcortical tissue microstructure were assessed using mean kurtosis tensor and mean diffusivity and compared between groups and tested for associations with neuropsychological outcomes. Alterations in microstructural tissue composition were found in the parietal, temporal, and occipital lobes in the congenital heart defects, with distinct mean kurtosis tensor cluster‐specific changes in the right visual cortex (pericalcarine gyrus, P=0.002; occipital part of fusiform and lingual gyri, P=0.019). Altered microstructural tissue composition in the subcortical structures was uncovered in atrial septal defects but not in ventricular septal defects. Associations were found between altered cerebral microstructure and social recognition and executive function. Conclusions Children operated for simple congenital heart defects demonstrated altered microstructural tissue composition in the cerebral cortex and subcortical structures during adulthood when compared with healthy peers. Alterations in cerebral microstructural tissue composition were associated with poorer neuropsychological performance. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03871881.
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Affiliation(s)
- Benjamin Asschenfeldt
- Department of Cardiothoracic & Vascular Surgery Aarhus University Hospital Denmark.,Department of Clinical Medicine Aarhus University Denmark
| | - Lars Evald
- Department of Clinical Medicine Aarhus University Denmark.,Hammel Neurorehabilitation Centre and University Research Clinic Denmark
| | - Camilla Salvig
- Department of Cardiothoracic & Vascular Surgery Aarhus University Hospital Denmark
| | - Johan Heiberg
- Department of Cardiothoracic & Vascular Surgery Aarhus University Hospital Denmark.,Department of Clinical Medicine Aarhus University Denmark
| | - Leif Østergaard
- Center of Functionally Integrative Neuroscience Aarhus University Denmark.,Department of Clinical Medicine Aarhus University Denmark.,Neuroradiology Research Unit, Department of Radiology Aarhus University Hospital Denmark
| | - Simon Fristed Eskildsen
- Center of Functionally Integrative Neuroscience Aarhus University Denmark.,Department of Clinical Medicine Aarhus University Denmark
| | - Vibeke Elisabeth Hjortdal
- Department of Clinical Medicine Aarhus University Denmark.,Department of Cardiothoracic Surgery, Rigshospitalet and Institute of Clinical Medicine University of Copenhagen Denmark
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Chung S, Chen J, Li T, Wang Y, Lui YW. Investigating Brain White Matter in Football Players with and without Concussion Using a Biophysical Model from Multishell Diffusion MRI. AJNR Am J Neuroradiol 2022; 43:823-828. [PMID: 35589140 DOI: 10.3174/ajnr.a7522] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 04/04/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE There have been growing concerns around potential risks related to sports-related concussion and contact sport exposure to repetitive head impacts in young athletes. Here we investigate WM microstructural differences between collegiate football players with and without sports-related concussion. MATERIALS AND METHODS The study included 78 collegiate athletes (24 football players with sports-related concussion, 26 football players with repetitive head impacts, and 28 non-contact-sport control athletes), available through the Federal Interagency Traumatic Brain Injury Research registry. Diffusion metrics of diffusion tensor/kurtosis imaging and WM tract integrity were calculated. Tract-Based Spatial Statistics and post hoc ROI analyses were performed to test group differences. RESULTS Significantly increased axial kurtosis in those with sports-related concussion compared with controls was observed diffusely across the whole-brain WM, and some focal areas demonstrated significantly higher mean kurtosis and extra-axonal axial diffusivity in sports-related concussion. The extent of significantly different WM regions decreased across time points and remained present primarily in the corpus callosum. Similar differences in axial kurtosis were found between the repetitive head impact and control groups. Other significant differences were seen at unrestricted return-to-play with lower radial kurtosis and intra-axonal diffusivity in those with sports-related concussion compared with the controls, mainly restricted to the posterior callosum. CONCLUSIONS This study highlights the fact that there are differences in diffusion microstructure measures that are present not only between football players with sports-related injuries and controls, but that there are also measurable differences between football players with repetitive head impacts and controls. This work reinforces previous work showing that the corpus callosum is specifically implicated in sports-related concussion and also suggests this to be true for repetitive head impacts.
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Affiliation(s)
- S Chung
- From the Department of Radiology (S.C., Y.W.L.), Center for Advanced Imaging Innovation and Research .,Department of Radiology (S.C., Y.W.L.), Bernard and Irene Schwartz Center for Biomedical Imaging, New York University Grossman School of Medicine, New York, New York
| | - J Chen
- Department of Electrical and Computer Engineering (J.C., T.L., Y.W.), New York University Tandon School of Engineering, Brooklyn, New York
| | - T Li
- Department of Electrical and Computer Engineering (J.C., T.L., Y.W.), New York University Tandon School of Engineering, Brooklyn, New York
| | - Y Wang
- Department of Electrical and Computer Engineering (J.C., T.L., Y.W.), New York University Tandon School of Engineering, Brooklyn, New York
| | - Y W Lui
- From the Department of Radiology (S.C., Y.W.L.), Center for Advanced Imaging Innovation and Research.,Department of Radiology (S.C., Y.W.L.), Bernard and Irene Schwartz Center for Biomedical Imaging, New York University Grossman School of Medicine, New York, New York
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32
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Lo YC, Li TJT, Lin TC, Chen YY, Kang JH. Microstructural Evidence of Neuroinflammation for Psychological Symptoms and Pain in Patients with Fibromyalgia. J Rheumatol 2022; 49:942-947. [DOI: 10.3899/jrheum.211170] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/20/2022] [Indexed: 11/22/2022]
Abstract
Objective In patients with fibromyalgia (FM), the brain shows altered structure and functional connectivity, but the mechanisms underlying these changes remain unclear. This study investigated the associated changes in brain microstructures and neuroinflammation of patients with FM. Methods We recruited 14 patients with FM and 14 healthy controls. Visual analog scale (VAS), Beck's Anxiety Inventory (BAI), and Beck's Depression Inventory-II (BDI-II) were used for assessing their pain, anxiety, and depression levels, respectively. Diffusion kurtosis imaging (DKI) was used to visualize microstructural alterations associated with neuroinflammation in specific brain regions. The biomarkers for the neuron damage, including serum tau and amyloid β protein fragment 1-42 (Aβ1-42) levels, were assessed. Spearman correlation of DKI parameters with VAS, BAI, and BDI-II scores and tau and Aβ1-42 levels were assessed. Results The patients with FM had significantly higher levels of Aβ1-42 levels compared with the controls. Compared with the controls, the patients showed significantly lower DKI parameters in the bilateral dorsal–lateral prefrontal cortex and orbital–frontal cortex. The patients showed a significant correlation between the axial kurtosis values of the amygdala and VAS scores (left: rho = -0.603, p = 0.022; right: rho = -7.04, p = 0.005). Conclusion To the best of our knowledge, this is the first study to use DKI to examine the brain of FM patients. We noted significant DKI changes at specific areas associated with neuroinflammation in patients with FM. Our results provide valuable information on brain neuroinflammation and pathophysiological changes in patients with FM.
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Li Q, Cao J, Liu X, Luo X, Su G, Wang D, Lin B. The diagnostic value of diffusion kurtosis imaging in Parkinson's disease: a systematic review and meta-analysis. ANNALS OF TRANSLATIONAL MEDICINE 2022; 10:474. [PMID: 35571428 PMCID: PMC9096385 DOI: 10.21037/atm-22-1461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/20/2022] [Indexed: 11/17/2022]
Abstract
Background Under the background that diffusion kurtosis imaging (DKI) has become a research hotspot of central nervous system diseases, there are no studies with large sample size evaluating the value of DKI in diagnosing Parkinson's disease (PD). Moreover, the diagnostic efficacy of DKI in PD is not consistent. Therefore, the main purpose of this study is to use the method of meta-analysis, to summarize and evaluate the diagnostic efficacy of DKI in the identification of PD, and to explore the value of its clinical application. Methods We use PICOS principles for project design. The included patients were PD patients, and the control group were healthy volunteers. We hope to use DKI to make a differential diagnosis between the two, and this study is a diagnostic test. We performed a literature search of English (PubMed, Embase, Cochrane Library, etc.) and Chinese (China knowledge Network, Wanfang Data Knowledge Service platform, China Science and Technology Journal Database, China Biomedical Literature Service system) databases for related literatures on the efficacy of DKI in the differential diagnosis of PD published before March 29, 2022. We used Revman 5.3 software to assess the quality of the literature, Meta-Disc 1.4 software for summarizing sensitivity (Sen), specificity (Spe), diagnostic odds ratios, and heterogeneity tests, and for subgrouping, and Stata 16.0 software for publication bias analysis. Results Fourteen articles were included through the literature search. The 14 studies included 535 patients with PD and 486 patients without PD. Most of the included literature had good clinical applicability and relatively low risk. By merging statistics, the results obtained were as follows: Sen =0.78 [95% confidence interval (CI): 0.74-0.81], Spe =0.83 (95% CI: 0.79-0.86), and the area under the summary receiver operating characteristic (SROC) curve was 0.8870. Discussion The results of the meta-analysis showed that magnetic resonance DKI has comparable diagnostic accuracy in the diagnosis of PD. However, this study also has limitations, and the use of different diagnostic gold standards in the included studies may have some impact on the case selection in the study.
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Affiliation(s)
- Qilin Li
- Department of Radiology, Zibo Central Hospital, Zibo, China
| | - Jinfeng Cao
- Department of Radiology, Zibo Central Hospital, Zibo, China
| | - Xinjiang Liu
- Department of Radiology, Shanghai Pudong Hospital (Pudong Hospital Affiliated to Fudan University), Shanghai, China
| | - Xin Luo
- Department of Radiology, Zibo Central Hospital, Zibo, China
| | - Ge Su
- College of Computer Science and Technology, Zhejiang University, Hangzhou, China
| | - Dejian Wang
- Department of R&D, Hangzhou Healink Technology, Hangzhou, China
| | - Bo Lin
- College of Computer Science and Technology, Zhejiang University, Hangzhou, China
- Innovation Centre for Information, Binjiang Institute of Zhejiang University, Hangzhou, China
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Novello L, Henriques RN, Ianuş A, Feiweier T, Shemesh N, Jovicich J. In vivo Correlation Tensor MRI reveals microscopic kurtosis in the human brain on a clinical 3T scanner. Neuroimage 2022; 254:119137. [PMID: 35339682 DOI: 10.1016/j.neuroimage.2022.119137] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 02/17/2022] [Accepted: 03/22/2022] [Indexed: 12/15/2022] Open
Abstract
Diffusion MRI (dMRI) has become one of the most important imaging modalities for noninvasively probing tissue microstructure. Diffusional Kurtosis MRI (DKI) quantifies the degree of non-gaussian diffusion, which in turn has been shown to increase sensitivity towards, e.g., disease and orientation mapping in neural tissue. However, the specificity of DKI is limited as different sources can contribute to the total intravoxel diffusional kurtosis, including: variance in diffusion tensor magnitudes (Kiso), variance due to diffusion anisotropy (Kaniso), and microscopic kurtosis (μK) related to restricted diffusion, microstructural disorder, and/or exchange. Interestingly, μK is typically ignored in diffusion MRI signal modeling as it is assumed to be negligible in neural tissues. However, recently, Correlation Tensor MRI (CTI) based on Double-Diffusion-Encoding (DDE) was introduced for kurtosis source separation, revealing non negligible μK in preclinical imaging. Here, we implemented CTI for the first time on a clinical 3T scanner and investigated the sources of total kurtosis in healthy subjects. A robust framework for kurtosis source separation in humans is introduced, followed by estimation of μK (and the other kurtosis sources) in the healthy brain. Using this clinical CTI approach, we find that μK significantly contributes to total diffusional kurtosis both in gray and white matter tissue but, as expected, not in the ventricles. The first μK maps of the human brain are presented, revealing that the spatial distribution of μK provides a unique source of contrast, appearing different from isotropic and anisotropic kurtosis counterparts. Moreover, group average templates of these kurtosis sources have been generated for the first time, which corroborated our findings at the underlying individual-level maps. We further show that the common practice of ignoring μK and assuming the multiple gaussian component approximation for kurtosis source estimation introduces significant bias in the estimation of other kurtosis sources and, perhaps even worse, compromises their interpretation. Finally, a twofold acceleration of CTI is discussed in the context of potential future clinical applications. We conclude that CTI has much potential for future in vivo microstructural characterizations in healthy and pathological tissue.
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Affiliation(s)
- Lisa Novello
- Center for Mind/Brain Sciences - CIMeC, University of Trento, Rovereto, Italy.
| | | | - Andrada Ianuş
- Champalimaud Research, Champalimaud Foundation, Lisbon, Portugal
| | | | - Noam Shemesh
- Champalimaud Research, Champalimaud Foundation, Lisbon, Portugal
| | - Jorge Jovicich
- Center for Mind/Brain Sciences - CIMeC, University of Trento, Rovereto, Italy
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Neurofunctional and neuroimaging readouts for designing a preclinical stem-cell therapy trial in experimental stroke. Sci Rep 2022; 12:4700. [PMID: 35304540 PMCID: PMC8933390 DOI: 10.1038/s41598-022-08713-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/09/2022] [Indexed: 11/08/2022] Open
Abstract
With the aim of designing a preclinical study evaluating an intracerebral cell-based therapy for stroke, an observational study was performed in the rat suture model of ischemic stroke. Objectives were threefold: (i) to characterize neurofunctional and imaging readouts in the first weeks following transient ischemic stroke, according to lesion subtype (hypothalamic, striatal, corticostriatal); (ii) to confirm that intracerebral administration does not negatively impact these readouts; and (iii) to calculate sample sizes for a future therapeutic trial using these readouts as endpoints. Our results suggested that the most relevant endpoints were side bias (staircase test) and axial diffusivity (AD) (diffusion tensor imaging). Hypothalamic-only lesions did not affect those parameters, which were close to normal. Side bias in striatal lesions reached near-normal levels within 2 weeks, while rats with corticostriatal lesions remained impaired until week 14. AD values were decreased at 4 days and increased at 5 weeks post-surgery, with a subtype gradient: hypothalamic < striatal < corticostriatal. Intracerebral administration did not impact these readouts. After sample size calculation (18-147 rats per group according to the endpoint considered), we conclude that a therapeutic trial based on both readouts would be feasible only in the framework of a multicenter trial.
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Raj S, Vyas S, Modi M, Garg G, Singh P, Kumar A, Kamal Ahuja C, Goyal MK, Govind V. Comparative Evaluation of Diffusion Kurtosis Imaging and Diffusion Tensor Imaging in Detecting Cerebral Microstructural Changes in Alzheimer Disease. Acad Radiol 2022; 29 Suppl 3:S63-S70. [PMID: 33612351 DOI: 10.1016/j.acra.2021.01.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/15/2021] [Accepted: 01/16/2021] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Comparative evaluation of diffusion kurtosis imaging (DKI) and diffusion tensor imaging (DTI) using a whole-brain atlas to comprehensively evaluate microstructural changes in the brain of Alzheimer disease (AzD) patients. METHODS Twenty-seven AzD patients and 25 age-matched controls were included. MRI data was analyzed using a whole-brain atlas with inclusion of 98 region of interests. White matter (WM) microstructural changes were assessed by Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), Kurtosis fractional anisotropy (KFA), mean kurtosis (MK), axial kurtosis (AK) and radial kurtosis (RK). Gray matter (GM) integrity was evaluated using KFA, MK, RK, AK and MD. Comparison of the DKI and DTI metrics were done using student t-test (p ≤ 0.001). RESULTS In AzD patients widespread increase in MD, AD and RD were found in various WM and GM region of interests. The extent of abnormality for DKI parameters was more limited in both GM and WM regions and revealed reduced kurtosis values except in lentiform nuclei. Both DKI and DTI parameters were sensitive to detect abnormality in WM areas with coherent and complex fiber arrangement. Receiver operating characteristic curve analysis for hippocampal values revealed the highest specificity of 88% for AK <0.6965 and highest sensitivity of 95.2% for MD >1.2659. CONCLUSION AzD patients have microstructural changes in both WM and GM and are well-depicted by both DKI and DTI. The alterations in kurtosis parameters, however, are more limited and correlate with areas in the brain primarily involved in cognition.
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Chourrout M, Rositi H, Ong E, Hubert V, Paccalet A, Foucault L, Autret A, Fayard B, Olivier C, Bolbos R, Peyrin F, Crola-da-Silva C, Meyronet D, Raineteau O, Elleaume H, Brun E, Chauveau F, Wiart M. Brain virtual histology with X-ray phase-contrast tomography Part I: whole-brain myelin mapping in white-matter injury models. BIOMEDICAL OPTICS EXPRESS 2022; 13:1620-1639. [PMID: 35415001 PMCID: PMC8973191 DOI: 10.1364/boe.438832] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 10/08/2021] [Accepted: 11/02/2021] [Indexed: 06/14/2023]
Abstract
White-matter injury leads to severe functional loss in many neurological diseases. Myelin staining on histological samples is the most common technique to investigate white-matter fibers. However, tissue processing and sectioning may affect the reliability of 3D volumetric assessments. The purpose of this study was to propose an approach that enables myelin fibers to be mapped in the whole rodent brain with microscopic resolution and without the need for strenuous staining. With this aim, we coupled in-line (propagation-based) X-ray phase-contrast tomography (XPCT) to ethanol-induced brain sample dehydration. We here provide the proof-of-concept that this approach enhances myelinated axons in rodent and human brain tissue. In addition, we demonstrated that white-matter injuries could be detected and quantified with this approach, using three animal models: ischemic stroke, premature birth and multiple sclerosis. Furthermore, in analogy to diffusion tensor imaging (DTI), we retrieved fiber directions and DTI-like diffusion metrics from our XPCT data to quantitatively characterize white-matter microstructure. Finally, we showed that this non-destructive approach was compatible with subsequent complementary brain sample analysis by conventional histology. In-line XPCT might thus become a novel gold-standard for investigating white-matter injury in the intact brain. This is Part I of a series of two articles reporting the value of in-line XPCT for virtual histology of the brain; Part II shows how in-line XPCT enables the whole-brain 3D morphometric analysis of amyloid- β (A β ) plaques.
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Affiliation(s)
- Matthieu Chourrout
- Univ-Lyon, Lyon Neuroscience
Research Center, CNRS UMR5292, Inserm U1028,
Université Claude Bernard Lyon 1, Lyon, France
- Co-first authors
| | - Hugo Rositi
- Univ-Clermont Auvergne; CNRS;
SIGMA Clermont; Institut Pascal,
Clermont-Ferrand, France
- Co-first authors
| | - Elodie Ong
- Univ-Lyon, CarMeN
laboratory, Inserm U1060, INRA U1397, Université
Claude Bernard Lyon 1, INSA Lyon, Charles Mérieux Medical
School, F-69600, Oullins, France
- Univ-Lyon, Hospices Civils de
Lyon, Lyon, France
| | - Violaine Hubert
- Univ-Lyon, CarMeN
laboratory, Inserm U1060, INRA U1397, Université
Claude Bernard Lyon 1, INSA Lyon, Charles Mérieux Medical
School, F-69600, Oullins, France
| | - Alexandre Paccalet
- Univ-Lyon, CarMeN
laboratory, Inserm U1060, INRA U1397, Université
Claude Bernard Lyon 1, INSA Lyon, Charles Mérieux Medical
School, F-69600, Oullins, France
| | - Louis Foucault
- Univ-Lyon, Université
Claude Bernard Lyon 1, Inserm, Stem Cell and Brain
Research Institute U1208, 69500 Bron, France
| | | | | | - Cécile Olivier
- Univ-Lyon, INSA-Lyon,
Université Claude Bernard Lyon 1,
CNRS, Inserm, CREATIS UMR5220, U1206, F-69621, France
| | | | - Françoise Peyrin
- Univ-Lyon, INSA-Lyon,
Université Claude Bernard Lyon 1,
CNRS, Inserm, CREATIS UMR5220, U1206, F-69621, France
| | - Claire Crola-da-Silva
- Univ-Lyon, CarMeN
laboratory, Inserm U1060, INRA U1397, Université
Claude Bernard Lyon 1, INSA Lyon, Charles Mérieux Medical
School, F-69600, Oullins, France
| | | | - Olivier Raineteau
- Univ-Lyon, Université
Claude Bernard Lyon 1, Inserm, Stem Cell and Brain
Research Institute U1208, 69500 Bron, France
| | - Héléne Elleaume
- Université Grenoble
Alpes, Inserm UA7 Strobe, Grenoble, France
| | - Emmanuel Brun
- Université Grenoble
Alpes, Inserm UA7 Strobe, Grenoble, France
| | - Fabien Chauveau
- Univ-Lyon, Lyon Neuroscience
Research Center, CNRS UMR5292, Inserm U1028,
Université Claude Bernard Lyon 1, Lyon, France
- CNRS, Lyon,
France
- Co-last authors
| | - Marlene Wiart
- Univ-Lyon, CarMeN
laboratory, Inserm U1060, INRA U1397, Université
Claude Bernard Lyon 1, INSA Lyon, Charles Mérieux Medical
School, F-69600, Oullins, France
- CNRS, Lyon,
France
- Co-last authors
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Fan L, Ibrahim FEEM, Chu X, Fu Y, Yan H, Wu Z, Tao C, Chen X, Ma Y, Guo Y, Dong Y, Yang C, Ge Y. Altered Microstructural Changes Detected by Diffusion Kurtosis Imaging in Patients With Cognitive Impairment After Acute Cerebral Infarction. Front Neurol 2022; 13:802357. [PMID: 35295835 PMCID: PMC8918512 DOI: 10.3389/fneur.2022.802357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/17/2022] [Indexed: 12/02/2022] Open
Abstract
Objective To detect the microstructural changes in patients with cognitive impairment after acute cerebral infarction using diffusion kurtosis imaging (DKI). Materials and Methods A total of 70 patients with acute cerebral infarction were divided into two groups: 35 patients with cognitive impairment (VCI group), and 35 patients without cognitive impairment (N-VCI group), according to mini-mental state examination (MMSE) score. Healthy individuals (n = 36) were selected as the normal control (NORM) group. DKI parameters from 28 different brain regions of interest (ROIs) were selected, measured, and compared. Results VCI group patients had significantly higher mean diffusion (MD) and significantly lower mean kurtosis (MK) values in most ROIs than those in the N-VCI and NORM groups. DKI parameters in some ROIs correlated significantly with MMSE score. The splenium of corpus callosum MD was most correlated with MMSE score, the correlation coefficient was −0.652, and this parameter had good ability to distinguish patients with VCI from healthy controls; at the optimal cut-off MD value (0.9915), sensitivity was 91.4%, specificity 100%, and the area under the curve value 0.964. Conclusions Pathological changes in some brain regions may underlie cognitive impairment after acute cerebral infarction, especially the splenium of corpus callosum. These preliminary results suggest that, in patients with VCI, DKI may be useful for assessing microstructural tissue damage.
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Gupta P, Vyas S, Salan T, Jain C, Taneja S, Dhiman RK, Singh P, Ahuja CK, Ray N, Govind V. Whole brain atlas-based diffusion kurtosis imaging parameters for evaluation of minimal hepatic encephalopathy. Neuroradiol J 2022; 35:67-76. [PMID: 34187242 PMCID: PMC8826285 DOI: 10.1177/19714009211026924] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND AND PURPOSES Minimal hepatic encephalopathy (MHE) has no recognizable clinical symptoms, but patients have cognitive and psychomotor deficits. Hyperammonemia along with neuroinflammation lead to microstructural changes in cerebral parenchyma. Changes at conventional imaging are detected usually at the overt clinical stage, but microstructural alterations by advanced magnetic resonance imaging techniques can be detected at an early stage. MATERIALS AND METHODS Whole brain diffusion kurtosis imaging (DKI) data acquired at 3T was analyzed to investigate microstructural parenchymal changes in 15 patients with MHE and compared with 15 age- and sex-matched controls. DKI parametric maps, namely kurtosis fractional anisotropy (kFA), mean kurtosis (MK), axial kurtosis (AK) and radial kurtosis (RK), were evaluated at 64 white matter (WM) and gray matter (GM) regions of interest (ROIs) in the whole brain and correlated with the psychometric hepatic encephalopathy score (PHES). RESULTS The MHE group showed a decrease in kFA and AK across the whole brain, whereas MK and RK decreased in WM ROIs but increased in several cortical and deep GM ROIs. These alterations were consistent with brain regions involved in cognitive function. Significant moderate to strong correlations (-0.52 to -0.66; 0.56) between RK, MK and kFA kurtosis metrics and PHES were observed. CONCLUSION DKI parameters show extensive microstructural brain abnormalities in MHE with minor correlation between the severity of tissue damage and psychometric scores.
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Affiliation(s)
- Prateek Gupta
- Department of Radiodiagnosis and
Imaging, Postgraduate Institute of Medical Education and Research, Chandigarh,
India
| | - Sameer Vyas
- Department of Radiodiagnosis and
Imaging, Postgraduate Institute of Medical Education and Research, Chandigarh,
India,Sameer Vyas, Department of Radiodiagnosis
and Imaging, Postgraduate Institute of Medical Education and Research,
Chandigarh, India.
| | - Teddy Salan
- Department of Radiology, University
of Miami, USA
| | - Chirag Jain
- Department of Radiodiagnosis and
Imaging, Postgraduate Institute of Medical Education and Research, Chandigarh,
India
| | - Sunil Taneja
- Department of Hepatology,
Postgraduate Institute of Medical Education and Research, Chandigarh,
India
| | - RK Dhiman
- Department of Hepatology,
Postgraduate Institute of Medical Education and Research, Chandigarh,
India
| | - Paramjeet Singh
- Department of Radiodiagnosis and
Imaging, Postgraduate Institute of Medical Education and Research, Chandigarh,
India
| | - Chirag K Ahuja
- Department of Radiodiagnosis and
Imaging, Postgraduate Institute of Medical Education and Research, Chandigarh,
India
| | - Nirmalya Ray
- Department of Radiodiagnosis and
Imaging, Postgraduate Institute of Medical Education and Research, Chandigarh,
India
| | - Varan Govind
- Department of Radiology, University
of Miami, USA
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Wei Y, Wang C, Liu J, Miao P, Wei S, Wang Y, Wu L, Xu B, Han S, Wei Y, Wang K, Cheng J. Widespread White Matter Microstructure Alterations Based on Diffusion Tensor Imaging and Diffusion Kurtosis Imaging in Patients With Pontine Infarction. Front Aging Neurosci 2022; 13:758236. [PMID: 34975452 PMCID: PMC8714656 DOI: 10.3389/fnagi.2021.758236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 10/19/2021] [Indexed: 12/16/2022] Open
Abstract
Neurological deficits after stroke are closely related to white matter microstructure damage. However, secondary changes in white matter microstructure after pontine infarction (PI) in the whole brain remain unclear. This study aimed to investigate the correlation of diffusion kurtosis imaging (DKI)-derived diffusion and kurtosis parameters of abnormal white matter tracts with behavioral function in patients with chronic PI. Overall, 60 patients with unilateral chronic PI (33 patients with left PI and 27 patients with right PI) and 30 normal subjects were recruited and underwent DKI scans. Diffusion parameters derived from diffusion tensor imaging (DTI) and DKI and kurtosis parameters derived from DKI were obtained. Between-group differences in multiple parameters were analyzed to assess the changes in abnormal white matter microstructure. Moreover, we also calculated the sensitivities of different diffusion and kurtosis parameters of DTI and DKI for identifying abnormal white matter tracts. Correlations between the DKI-derived parameters in secondary microstructure changes and behavioral scores in the PI were analyzed. Compared with the NC group, both left PI and right PI groups showed more extensive perilesional and remote white matter microstructure changes. The DKI-derived diffusion parameters showed higher sensitivities than did the DTI-derived parameters. Further, DKI-derived diffusion and kurtosis parameters in abnormal white matter regions were correlated with impaired motor and cognitive function in patients with PI. In conclusion, PI could lead to extensive white matter tracts impairment in perilesional and remote regions. Further, the diffusion and kurtosis parameters could be complementary for identifying comprehensive tissue microstructural damage after PI.
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Affiliation(s)
- Ying Wei
- Department of Magnetic Resonance Imaging (MRI), The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Caihong Wang
- Department of Magnetic Resonance Imaging (MRI), The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jingchun Liu
- Tianjin Key Laboratory of Functional Imaging, Department of Radiology, Tianjin, China
| | - Peifang Miao
- Department of Magnetic Resonance Imaging (MRI), The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Sen Wei
- Department of Neuro-Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yingying Wang
- Department of Magnetic Resonance Imaging (MRI), The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Luobing Wu
- The First Affiliated Hospital of Henan University of Science and Technology, Luoyang, China
| | - Boyan Xu
- Beijing Intelligent Brain Cloud, Inc., Beijing, China
| | - Shaoqiang Han
- Department of Magnetic Resonance Imaging (MRI), The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yarui Wei
- Department of Magnetic Resonance Imaging (MRI), The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Kaiyu Wang
- GE Healthcare MR Research, Beijing, China
| | - Jingliang Cheng
- Department of Magnetic Resonance Imaging (MRI), The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Diffusional kurtosis imaging as a possible prognostic marker of cervical incomplete spinal cord injury outcome: a prospective pilot study. Acta Neurochir (Wien) 2022; 164:25-32. [PMID: 34671848 DOI: 10.1007/s00701-021-05018-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 07/11/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Spinal cord injury (SCI) is associated with substantial chronic morbidity and mortality. Routine imaging techniques such as T1- and T2-weighted magnetic resonance imaging (MRI) are not effective in predicting neurological deficiency grade or outcome. Diffusional kurtosis imaging (DKI) is an MR imaging technique that provides microstructural information about biological tissue. There are no longitudinal prospective studies assessing DKI metrics in acute traumatic SCI. Therefore, the purpose of this study was to establish a DKI protocol for acute SCI and correlate the DKI metrics to the functional neurological outcome of the patients. METHODS Eight consecutive SCI patients referred to our institution with cervical SCI were included in the study. An acute diagnostic MRI scan was supplemented with a novel fast, mean kurtosis DKI protocol, which describes the average deviation from Gaussian diffusional along nine different directions. Mean kurtosis values were measured at the injury site and normalized to the mean kurtosis values of a non-injured site. At discharge form specialized rehabilitation, patients were evaluated using the Spinal Cord Independence Measure-III (SCIM-III). The DKI metrics and SCIM-III were analysed using Spearman's rank correlation. RESULTS This pilot study found a significant correlation between decreasing mean kurtosis values at the injury site of the spinal cord and higher grade of disability measured by the SCIM-III (p = 0.002). CONCLUSION This pilot study found that DKI may be a valuable tool as a prognostic marker in the acute phase of SCI.
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Hutchinson E, Osting S, Rutecki P, Sutula T. Diffusion Tensor Orientation as a Microstructural MRI Marker of Mossy Fiber Sprouting After TBI in Rats. J Neuropathol Exp Neurol 2021; 81:27-47. [PMID: 34865073 DOI: 10.1093/jnen/nlab123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Diffusion tensor imaging (DTI) metrics are highly sensitive to microstructural brain alterations and are potentially useful imaging biomarkers for underlying neuropathologic changes after experimental and human traumatic brain injury (TBI). As potential imaging biomarkers require direct correlation with neuropathologic alterations for validation and interpretation, this study systematically examined neuropathologic abnormalities underlying alterations in DTI metrics in the hippocampus and cortex following controlled cortical impact (CCI) in rats. Ex vivo DTI metrics were directly compared with a comprehensive histologic battery for neurodegeneration, microgliosis, astrocytosis, and mossy fiber sprouting by Timm histochemistry at carefully matched locations immediately, 48 hours, and 4 weeks after injury. DTI abnormalities corresponded to spatially overlapping but temporally distinct neuropathologic alterations representing an aggregate measure of dynamic tissue damage and reorganization. Prominent DTI alterations of were observed for both the immediate and acute intervals after injury and associated with neurodegeneration and inflammation. In the chronic period, diffusion tensor orientation in the hilus of the dentate gyrus became prominently abnormal and was identified as a reliable structural biomarker for mossy fiber sprouting after CCI in rats, suggesting potential application as a biomarker to follow secondary progression in experimental and human TBI.
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Affiliation(s)
- Elizabeth Hutchinson
- From the Department of Biomedical Engineering, University of Arizona, Tucson, Arizona, USA (EH); and Department of Neurology, University of Wisconsin, Madison, Wisconsin, USA (SO, PR, TS)
| | - Susan Osting
- From the Department of Biomedical Engineering, University of Arizona, Tucson, Arizona, USA (EH); and Department of Neurology, University of Wisconsin, Madison, Wisconsin, USA (SO, PR, TS)
| | - Paul Rutecki
- From the Department of Biomedical Engineering, University of Arizona, Tucson, Arizona, USA (EH); and Department of Neurology, University of Wisconsin, Madison, Wisconsin, USA (SO, PR, TS)
| | - Thomas Sutula
- From the Department of Biomedical Engineering, University of Arizona, Tucson, Arizona, USA (EH); and Department of Neurology, University of Wisconsin, Madison, Wisconsin, USA (SO, PR, TS)
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Venkatesh A, Daugherty AM, Bennett IJ. Neuroimaging measures of iron and gliosis explain memory performance in aging. Hum Brain Mapp 2021; 42:5761-5770. [PMID: 34520095 PMCID: PMC8559505 DOI: 10.1002/hbm.25652] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/18/2021] [Accepted: 08/21/2021] [Indexed: 11/13/2022] Open
Abstract
Evidence from animal and histological studies has indicated that accumulation of iron in the brain results in reactive gliosis that contributes to cognitive deficits. The current study extends these findings to human cognitive aging and suggests that magnetic resonance imaging (MRI) techniques like quantitative relaxometry can be used to study iron and its effects in vivo. The effects of iron on microstructure and memory performance were examined using a combination of quantitative relaxometry and multicompartment diffusion imaging in 35 young (21.06 ± 2.18 years) and 28 older (72.58 ± 6.47 years) adults, who also completed a memory task. Replicating past work, results revealed age‐related increases in iron content (R2*) and diffusion, and decreases in memory performance. Independent of age group, iron content was significantly related to restricted (intracellular) diffusion in regions with low‐moderate iron (hippocampus, caudate) and to all diffusion metrics in regions with moderate‐high iron (putamen, globus pallidus). This pattern is consistent with different stages of iron‐related gliosis, ranging from astrogliosis that may influence intracellular diffusion to microglial proliferation and increased vascular permeability that may influence all sources of diffusion. Further, hippocampal restricted diffusion was significantly related to memory performance, with a third of this effect related to iron content; consistent with the hypothesis that higher iron‐related astrogliosis in the hippocampus is associated with poorer memory performance. These results demonstrate the sensitivity of MRI to iron‐related gliosis and extend our understanding of its impact on cognition by showing that this relationship also explains individual differences in memory performance.
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Affiliation(s)
- Anu Venkatesh
- Department of Neuroscience, University of California Riverside, Riverside, California, USA
| | - Ana M Daugherty
- Department of Psychology, Wayne State University, Detroit, Michigan, USA
| | - Ilana J Bennett
- Department of Neuroscience, University of California Riverside, Riverside, California, USA.,Department of Psychology, University of California Riverside, Riverside, California, USA
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Zheng H, Lin J, Lin Q, Zheng W. Magnetic Resonance Image of Neonatal Acute Bilirubin Encephalopathy: A Diffusion Kurtosis Imaging Study. Front Neurol 2021; 12:645534. [PMID: 34512498 PMCID: PMC8425508 DOI: 10.3389/fneur.2021.645534] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 07/16/2021] [Indexed: 01/31/2023] Open
Abstract
Background and Objective: The abnormal T1-weighted imaging of MRI can be used to characterize neonatal acute bilirubin encephalopathy (ABE) in newborns, but has limited use in evaluating the severity and prognosis of ABE. This study aims to assess the value of diffusion kurtosis imaging (DKI) in detecting ABE and understanding its pathogenesis. Method: Seventy-six newborns with hyperbilirubinemia were grouped into three groups (mild group, moderate group, and severe group) based on serum bilirubin levels. All the patients underwent conventional MRI and DKI serial, as well as 40 healthy full-term infants (control group). The regions of interest (ROIs) were the bilateral globus pallidus, dorsal thalamus, frontal lobe, auditory radiation, superior temporal gyrus, substantia nigra, hippocampus, putamen, and inferior olivary nucleus. The values of mean diffusivity (MD), axial kurtosis (AK), radial kurtosis (RK), and mean kurtosis (MK), and fractional anisotropy (FA), radial diffusivity (RD), and axis diffusivity (AD) of the ROIs were evaluated. All newborns were followed up and evaluated using the Denver Development Screening Test (DDST). According to the follow-up results, the patients were divided into the normal group, the suspicious abnormal group, and the abnormal group. Result: Compared with the control group, significant differences were observed with the increased MK of dorsal thalamus, AD of globus pallidus in the moderate group, and increased RD, MK, AK, and RK value of globus pallidus, dorsal thalamus, auditory radiation, superior temporal gyrus, and hippocampus in the severe group. The peak value of total serum bilirubin was moderately correlated with the MK of globus pallidus, dorsal thalamus, and auditory radiation and was positively correlated with the other kurtosis value. Out of 76 patients, 40 finished the DDST, and only 9 patients showed an abnormality. Compared with the normal group, the AK value of inferior olivary nucleus showed significant differences (p < 0.05) in the suspicious abnormal group, and the MK of globus pallidus, temporal gyrus, and auditory radiation; RK of globus pallidus, dorsal thalamus, and auditory radiation; and MD of globus pallidus showed significant differences (p < 0.05) in the abnormal group. Conclusion: DKI can reflect the subtle structural changes of neonatal ABE, and MK is a sensitive indicator to indicate the severity of brain damage.
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Affiliation(s)
- Hongyi Zheng
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou, China
| | - Jiefen Lin
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou, China
| | - Qihuan Lin
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou, China
| | - Wenbin Zheng
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou, China
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White matter tracts in Bipolar Disorder patients: A comparative study based on diffusion kurtosis and tensor imaging. J Affect Disord 2021; 292:45-55. [PMID: 34098469 DOI: 10.1016/j.jad.2021.05.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 05/12/2021] [Accepted: 05/20/2021] [Indexed: 11/23/2022]
Abstract
BACKGROUND Diffusion kurtosis imaging (DKI), an extension of diffusion tensor imaging (DTI), is a powerful tool for studying human brain.The purpose is to investigate differences between DKI and DTI by comparing parameters in same analysis methods with bipolar disorder (BD) patients. METHODS In this study, we attained in 47 BD patients and 49 age-, sex-, and education-matched healthy controls, complimented DTI and DKI scanning and got Fractional Anisotropy (FA), Mean Diffusion (MD) and Mean Kurtosis (MK). Voxel-wise statistical analysis was performed by the tract-based spatial statistics (TBSS) analysis and atlas-based regional data analysis. RESULTS TBSS analysis showed more widespread regions and higher fidelity in DKI parameters than DTI parameters with the same p-value threshold, and DKI parameters showed significant alterations after Family-Wise Error correction. The DKI-FA value in the corpus callosum, bilateral cingulum (cingulate gyrus), bilateral superior corona radiata, left anterior corona radiata and left posterior corona radiata of BD patients was negatively correlated with the duration of illness. In the atlas-based regional data analysis, the effect size of DTI-FA, DTI-MD, DKI-FA and DKI-MD were quantified using Cohen's d value. DKI-FA and DKI-MD demonstrated more between-group different regions and the higher (p < 0.001) absolute Cohen's d value than DTI-FA. LIMITATIONS This study did not consider the difference between sub-types of BD. CONCLUSIONS Compared to DTI parameters, DKI parameters were more sensitive and stable to probe the local microstructure, and particularly powerful to exploit cerebral alterations in BD patients.
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Henriques RN, Jespersen SN, Jones DK, Veraart J. Toward more robust and reproducible diffusion kurtosis imaging. Magn Reson Med 2021; 86:1600-1613. [PMID: 33829542 PMCID: PMC8199974 DOI: 10.1002/mrm.28730] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 01/20/2021] [Accepted: 01/24/2021] [Indexed: 12/21/2022]
Abstract
PURPOSE The general utility of diffusion kurtosis imaging (DKI) is challenged by its poor robustness to imaging artifacts and thermal noise that often lead to implausible kurtosis values. THEORY AND METHODS A robust scalar kurtosis index can be estimated from powder-averaged diffusion-weighted data. We introduce a novel DKI estimator that uses this scalar kurtosis index as a proxy for the mean kurtosis to regularize the fit. RESULTS The regularized DKI estimator improves the robustness and reproducibility of the kurtosis metrics and results in parameter maps with enhanced quality and contrast. CONCLUSION Our novel DKI estimator promotes the wider use of DKI in clinical research and potentially diagnostics by improving the reproducibility and precision of DKI fitting and, as such, enabling enhanced visual, quantitative, and statistical analyses of DKI parameters.
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Affiliation(s)
| | - Sune N. Jespersen
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLabDepartment of Clinical MedicineAarhus UniversityAarhusDenmark
- Department of Physics and AstronomyAarhus UniversityAarhusDenmark
| | - Derek K. Jones
- CUBRICSchool of PsychologyCardiff UniversityCardiffUK
- Mary MacKillop Institute for Health ResearchAustralian Catholic UniversityMelbourneVictoriaAustralia
| | - Jelle Veraart
- Center for Biomedical ImagingNew York University Grossman School of MedicineNew YorkNYUSA
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McKenna F, Babb J, Miles L, Goff D, Lazar M. Reduced Microstructural Lateralization in Males with Chronic Schizophrenia: A Diffusional Kurtosis Imaging Study. Cereb Cortex 2021; 30:2281-2294. [PMID: 31819950 DOI: 10.1093/cercor/bhz239] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Decreased brain lateralization is considered a trait marker of schizophrenia. Whereas reductions in both functional and macrostructural gray matter laterality in schizophrenia are well established, the investigation of gray matter microstructural lateralization has so far been limited to a small number of ex vivo studies, which limits the understanding of neurobiological substrates involved and development of adequate treatments. The aim of the current study was to assess in vivo gray matter microstructure lateralization patterns in schizophrenia by employing the diffusion kurtosis imaging (DKI)-derived mean kurtosis (MK) metric. MK was calculated for 18 right-handed males with chronic schizophrenia and 19 age-matched healthy control participants in 46 bilateral gray matter regions of interest (ROI). Microstructural laterality indexes (μLIs) were calculated for each subject and ROI, and group comparisons were conducted across regions. The relationship between μLI values and performance on the Wisconsin Card Sorting Test (WCST) was also evaluated. We found that compared with healthy controls, males with chronic schizophrenia had significantly decreased μLI across cortical and subcortical gray matter regions, which was correlated with poorer performance on the WCST. Our results suggest the ability of DKI-derived MK to capture gray matter microstructural lateralization pathology in vivo.
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Affiliation(s)
- Faye McKenna
- Department of Radiology, Center for Biomedical Imaging, New York, NY 10016, USA.,Sackler Institute of Graduate Biomedical Sciences New York University School of Medicine, New York, NY 10016, USA
| | - James Babb
- Department of Radiology, Center for Biomedical Imaging, New York, NY 10016, USA
| | - Laura Miles
- Department of Radiology, Center for Biomedical Imaging, New York, NY 10016, USA
| | - Donald Goff
- Department of Psychiatry, New York University School of Medicine, New York, NY 10016, USA
| | - Mariana Lazar
- Department of Radiology, Center for Biomedical Imaging, New York, NY 10016, USA.,Sackler Institute of Graduate Biomedical Sciences New York University School of Medicine, New York, NY 10016, USA
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Bagdasarian FA, Yuan X, Athey J, Bunnell BA, Grant SC. NODDI highlights recovery mechanisms in white and gray matter in ischemic stroke following human stem cell treatment. Magn Reson Med 2021; 86:3211-3223. [PMID: 34355818 DOI: 10.1002/mrm.28929] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/22/2021] [Accepted: 06/28/2021] [Indexed: 12/20/2022]
Abstract
PURPOSE Diffusion MRI offers insight into ischemic stroke progression in both human and rodent models. However, diffusion MRI to evaluate therapeutic application of mesenchymal stem cells is limited. Robust analytical techniques are required to identify potential physiological changes as a function of cell therapy in stroke. Here, we seek to establish Neurite Orientation Dispersion and Density Imaging (NODDI) as a feasible method in evaluating stroke evolution in response to cell-based therapeutics. METHODS Diffusion MRI data at 21.1T were acquired from 16 male rats. Rats were grouped randomly: naïve (baseline, N = 5), stroke with injections of phosphate buffered saline (N = 6), stroke with injection of 2D human mesenchymal stem cells (hMSC, N = 5). Data were acquired on days 1, 3, 7, and 21 post-surgery. DTI and NODDI maps were generated, with regions of interest placed in the ischemic hemisphere external capsule and striatum. Diffusion parameters were compared between groups each day, and within groups across hemispheres and longitudinally. Behavioral characterizations were on days 0 (pre-surgery), 3, 7, 14, and 21. RESULTS The 2D hMSC preserved diffusional restriction in the external capsule compared to saline (day 1: MD, P = .4060; AD, P = .0220). NODDI indicates that hMSC may have preserved intracellular volume fractions (ICVF: day 1, P = .0086; day 3, P = .0021; day 21, P = .0383). Diffusion metrics of hMSC treated animals were comparable to naïve for the external capsule. CONCLUSIONS NODDI compliments DTI metrics, enhances interpretation of tissue outcome in ischemic stroke following hMSC application, and may be useful in evaluating or predicting therapeutic response.
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Affiliation(s)
- F Andrew Bagdasarian
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, USA.,Chemical & Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida, USA
| | - Xuegang Yuan
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, USA.,Chemical & Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida, USA
| | - Jacob Athey
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, USA.,Chemical & Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida, USA
| | - Bruce A Bunnell
- Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Samuel C Grant
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, USA.,Chemical & Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida, USA
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Oliviero S, Del Gratta C. Impact of the acquisition protocol on the sensitivity to demyelination and axonal loss of clinically feasible DWI techniques: a simulation study. MAGMA (NEW YORK, N.Y.) 2021; 34:523-543. [PMID: 33417079 DOI: 10.1007/s10334-020-00899-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 11/19/2020] [Accepted: 11/22/2020] [Indexed: 06/12/2023]
Abstract
OBJECTIVE To evaluate: (a) the specific effect that the demyelination and axonal loss have on the DW signal, and (b) the impact of the sequence parameters on the sensitivity to damage of two clinically feasible DWI techniques, i.e. DKI and NODDI. METHODS We performed a Monte Carlo simulation of water diffusion inside a novel synthetic model of white matter in the presence of axonal loss and demyelination, with three compartments with permeable boundaries between them. We compared DKI and NODDI in their ability to detect and assess the damage, using several acquisition protocols. We used the F test statistic as an index of the sensitivity for each DWI parameter to axonal loss and demyelination, respectively. RESULTS DKI parameters significantly changed with increasing axonal loss, but, in most cases, not with demyelination; all the NODDI parameters showed sensitivity to both the damage processes (at p < 0.01). However, the acquisition protocol strongly affected the sensitivity to damage of both the DKI and NODDI parameters and, especially for NODDI, the parameter absolute values also. DISCUSSION This work is expected to impact future choices for investigating white matter microstructure in focusing on specific stages of the disease, and for selecting the appropriate experimental framework to obtain optimal data quality given the purpose of the experiment.
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Affiliation(s)
- Stefania Oliviero
- Department Neurosciences, Imaging, and Clinical Sciences, Institute for Advanced Biomedical Technologies, ITAB, Gabriele D'Annunzio University, Chieti, Italy.
| | - Cosimo Del Gratta
- Department Neurosciences, Imaging, and Clinical Sciences, Institute for Advanced Biomedical Technologies, ITAB, Gabriele D'Annunzio University, Chieti, Italy
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Henriques RN, Jespersen SN, Shemesh N. Evidence for microscopic kurtosis in neural tissue revealed by correlation tensor MRI. Magn Reson Med 2021; 86:3111-3130. [PMID: 34329509 PMCID: PMC9290035 DOI: 10.1002/mrm.28938] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 07/01/2021] [Accepted: 07/04/2021] [Indexed: 12/14/2022]
Abstract
PURPOSE The impact of microscopic diffusional kurtosis (µK), arising from restricted diffusion and/or structural disorder, remains a controversial issue in contemporary diffusion MRI (dMRI). Recently, correlation tensor imaging (CTI) was introduced to disentangle the sources contributing to diffusional kurtosis, without relying on a-priori multi-gaussian component (MGC) or other microstructural assumptions. Here, we investigated µK in in vivo rat brains and assessed its impact on state-of-the-art methods ignoring µK. THEORY AND METHODS CTI harnesses double diffusion encoding (DDE) experiments, which were here improved for speed and minimal bias using four different sets of acquisition parameters. The robustness of the improved CTI protocol was assessed via simulations. In vivo CTI acquisitions were performed in healthy rat brains using a 9.4T pre-clinical scanner equipped with a cryogenic coil, and targeted the estimation of µK, anisotropic kurtosis, and isotropic kurtosis. RESULTS The improved CTI acquisition scheme substantially reduces scan time and importantly, also minimizes higher-order-term biases, thus enabling robust µK estimation, alongside Kaniso and Kiso metrics. Our CTI experiments revealed positive µK both in white and gray matter of the rat brain in vivo; µK is the dominant kurtosis source in healthy gray matter tissue. The non-negligible µK substantially were found to bias prior MGC analyses of Kiso and Kaniso . CONCLUSIONS Correlation Tensor MRI offers a more accurate and robust characterization of kurtosis sources than its predecessors. µK is non-negligible in vivo in healthy white and gray matter tissues and could be an important biomarker for future studies. Our findings thus have both theoretical and practical implications for future dMRI research.
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Affiliation(s)
| | - Sune N Jespersen
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Clinical Institute, Aarhus University, Aarhus, Denmark.,Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark
| | - Noam Shemesh
- Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal
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