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Issa ASM, Scheins J, Tellmann L, Brambilla CR, Lohmann P, Rota-Kops E, Herzog H, Neuner I, Shah NJ, Lerche C. Impact of improved dead time correction on the quantification accuracy of a dedicated BrainPET scanner. PLoS One 2024; 19:e0296357. [PMID: 38578749 PMCID: PMC10997125 DOI: 10.1371/journal.pone.0296357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 12/11/2023] [Indexed: 04/07/2024] Open
Abstract
OBJECTIVE Quantitative values derived from PET brain images are of high interest for neuroscientific applications. Insufficient DT correction (DTC) can lead to a systematic bias of the output parameters obtained by a detailed analysis of the time activity curves (TACs). The DTC method currently used for the Siemens 3T MR BrainPET insert is global, i.e., differences in DT losses between detector blocks are not considered, leading to inaccurate DTC and, consequently, to inaccurate measurements masked by a bias. However, following careful evaluation with phantom measurements, a new block-pairwise DTC method has demonstrated a higher degree of accuracy compared to the global DTC method. APPROACH Differences between the global and the block-pairwise DTC method were studied in this work by applying several radioactive tracers. We evaluated the impact on [11C]ABP688, O-(2-[18F]fluoroethyl)-L-tyrosine (FET), and [15O]H2O TACs. RESULTS For [11C]ABP688, a relevant bias of between -0.0034 and -0.0053 ml/ (cm3 • min) was found in all studied brain regions for the volume of distribution (VT) when using the current global DTC method. For [18F]FET-PET, differences of up to 10% were observed in the tumor-to-brain ratio (TBRmax), these differences depend on the radial distance of the maximum from the PET isocenter. For [15O]H2O, differences between +4% and -7% were observed in the GM region. Average biases of -4.58%, -3.2%, and -1.2% for the regional cerebral blood flow (CBF (K1)), the rate constant k2, and the volume of distribution VT were observed, respectively. Conversely, in the white matter region, average biases of -4.9%, -7.0%, and 3.8% were observed for CBF (K1), k2, and VT, respectively. CONCLUSION The bias introduced by the global DTC method leads to an overestimation in the studied quantitative parameters for all applications compared to the block-pairwise method. SIGNIFICANCE The observed differences between the two DTC methods are particularly relevant for research applications in neuroscientific studies as they affect the accuracy of quantitative Brain PET images.
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Affiliation(s)
- Ahlam Said Mohamad Issa
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
- JARA, BRAIN, Translational Medicine, Aachen, Germany
- Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
| | - Jürgen Scheins
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | - Lutz Tellmann
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | | | - Philipp Lohmann
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | - Elena Rota-Kops
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | - Hans Herzog
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
| | - Irene Neuner
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
- JARA, BRAIN, Translational Medicine, Aachen, Germany
- Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Aachen, Germany
| | - N. Jon Shah
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
- JARA, BRAIN, Translational Medicine, Aachen, Germany
- Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Institute of Neuroscience and Medicine 11, INM-11, JARA, Forschungszentrum Jülich, Jülich, Germany
| | - Christoph Lerche
- Institute of Neuroscience and Medicine 4, INM-4, Forschungszentrum Jülich, Jülich, Germany
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2
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Mc Veigh M, Bellan LM. Microfluidic synthesis of radiotracers: recent developments and commercialization prospects. LAB ON A CHIP 2024; 24:1226-1243. [PMID: 38165824 DOI: 10.1039/d3lc00779k] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
Positron emission tomography (PET) is a powerful diagnostic tool that holds incredible potential for clinicians to track a wide variety of biological processes using specialized radiotracers. Currently, however, a single radiotracer accounts for over 95% of procedures, largely due to the cost of radiotracer synthesis. Microfluidic platforms provide a solution to this problem by enabling a dose-on-demand pipeline in which a single benchtop platform would synthesize a wide array of radiotracers. In this review, we will explore the field of microfluidic production of radiotracers from early research to current development. Furthermore, the benefits and drawbacks of different microfluidic reactor designs will be analyzed. Lastly, we will discuss the various engineering considerations that must be addressed to create a fully developed, commercially effective platform that can usher the field from research and development to commercialization.
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Affiliation(s)
- Mark Mc Veigh
- Interdisciplinary Materials Science Program, Vanderbilt University, Nashville, TN, 37235, USA
| | - Leon M Bellan
- Department of Mechanical Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37235, USA
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3
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Frautschi PC, Singh AP, Stowe NA, Yu JPJ. Multimodal Neuroimaging of the Effect of Serotonergic Psychedelics on the Brain. AJNR Am J Neuroradiol 2024; 45:ajnr.A8118. [PMID: 38360790 DOI: 10.3174/ajnr.a8118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/20/2023] [Indexed: 02/17/2024]
Abstract
The neurobiological mechanisms underpinning psychiatric disorders such as treatment-resistant major depression, post-traumatic stress disorder, and substance use disorders, remain unknown. Psychedelic compounds, such as psilocybin, lysergic acid diethylamide, and N,N-dimethyltryptamine, have emerged as potential therapies for these disorders because of their hypothesized ability to induce neuroplastic effects and alter functional networks in the brain. Yet, the mechanisms underpinning the neurobiological treatment response remain obscure. Quantitative neuroimaging is uniquely positioned to provide insight into the neurobiological mechanisms of these emerging therapies and quantify the patient treatment response. This review aims to synthesize our current state-of-the-art understanding of the functional changes occurring in the brain following psilocybin, lysergic acid diethylamide, or N,N-dimethyltryptamine administration in human participants with fMRI and PET. We further aim to disseminate our understanding of psychedelic compounds as they relate to neuroimaging with the goal of improved diagnostics and treatment of neuropsychiatric illness.
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Affiliation(s)
- Paloma C Frautschi
- Department of Radiology (P.C.F., A.P.S., J.-P.J.Y.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Ajay P Singh
- Department of Radiology (P.C.F., A.P.S., J.-P.J.Y.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
- Graduate Program in Cellular and Molecular Biology (A.P.S., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
| | - Nicholas A Stowe
- Neuroscience Training Program, Wisconsin Institutes for Medical Research (N.A.S., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
| | - John-Paul J Yu
- Department of Radiology (P.C.F., A.P.S., J.-P.J.Y.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
- Neuroscience Training Program, Wisconsin Institutes for Medical Research (N.A.S., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
- Graduate Program in Cellular and Molecular Biology (A.P.S., J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
- Department of Biomedical Engineering (J.-P.J.Y.), University of Wisconsin-Madison, Madison, Wisconsin
- Department of Psychiatry (J.-P.J.Y.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
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4
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Nakatsuka K, Zanghi B, Hasegawa D. Efficacy evaluation of a commercially available MCT enriched therapeutic diet on dogs with idiopathic epilepsy treated with zonisamide: a prospective, randomized, double-blinded, placebo-controlled, crossover dietary preliminary study. BMC Vet Res 2023; 19:145. [PMID: 37674206 PMCID: PMC10481612 DOI: 10.1186/s12917-023-03710-4] [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: 03/23/2023] [Accepted: 08/28/2023] [Indexed: 09/08/2023] Open
Abstract
BACKGROUND Idiopathic epilepsy (IE) is a common, chronic brain dysfunction in dogs. Recently, the effect of feeding a diet enriched with medium-chain triglycerides (MCTs) on seizure frequency has been evaluated in several studies in dogs with IE. However, most dogs with IE in previous studies were treated with phenobarbital as the main antiseizure medication (ASM). In Japan, zonisamide (ZNS) is the most prescribed ASM for dogs with IE. The interaction between ZNS and various nutrients including MCTs and the potential effects on treatment efficacy resulting from combining these therapies have not been previously studied. A prospective, randomized, double-blinded, placebo-controlled, crossover dietary study was conducted. Dogs (n = 7) treated with ZNS were fed either a placebo diet (PL) or Purina ProPlan Veterinary Diet NeuroCare (NC) for 3 months, after which treatments were crossed over and continued for another 3 months. Seizure frequency (seizures/month; sz/m), blood tests including concentrations of ZNS and β-hydroxybutyric acid, and owner's visual analogue scale score were collected from all dogs for both treatment periods. RESULTS There was no significant difference in the seizure frequency between PL (2.95 ± 0.80 sz/m) and NC (1.90 ± 0.57 sz/m) during the 6 months of trial. Three of 7 dogs showed ≥ 50% seizure reduction, and 1 of those 3 dogs achieved seizure freedom in NC period. However, 2 of 7 dogs had no changes in epileptic seizure frequency, 2 of 7 dogs had a deterioration in seizure frequency in the NC period. Feeding the MCT diet concurrent with ZNS showed no apparent adverse effects and did not affect ZNS concentration. CONCLUSIONS This study indicated that the commercially available MCT-enriched diet (NC) can be safely used concurrently with ZNS for dogs with IE.
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Affiliation(s)
- Kazumasa Nakatsuka
- Department of Veterinary Pharmacology, Faculty of Agriculture, Tottori University, Tottori, Japan
- Academic, Nestlé Purina PetCare, Kobe, Japan
| | - Brian Zanghi
- Global Nutrition and Communications, Nestlé Purina PetCare, St. Louis, USA
| | - Daisuke Hasegawa
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Tokyo, Japan.
- The Research Center for Animal Life Sciences, Nippon Veterinary and Life Science University, Tokyo, Japan.
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5
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Lin Fracp P, Holloway L, Min Franzcr M, Lee Franzcr M, Fowler Franzcr A. Prognostic and predictive values of baseline and mid-treatment FDG-PET in oropharyngeal carcinoma treated with primary definitive (chemo)radiation and impact of HPV status: review of current literature and emerging roles. Radiother Oncol 2023; 184:109686. [PMID: 37142128 DOI: 10.1016/j.radonc.2023.109686] [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: 07/29/2022] [Revised: 04/16/2023] [Accepted: 04/24/2023] [Indexed: 05/06/2023]
Abstract
BACKGROUND AND PURPOSE This study provides a review of the literature assessing whether semiquantitative PET parameters acquired at baseline and/or during definitive (chemo)radiotherapy ("prePET" and "iPET") can predict survival outcomes in patients with oropharyngeal squamous cell carcinoma (OPC), and the impact of human papilloma virus (HPV) status. MATERIAL AND METHODS A literature search was carried out using PubMed and Embase between 2001 to 2021 in accordance with PRISMA. RESULTS The analysis included 22 FDG-PET/CT studies1-22, 19 pre-PET and 3 both pre-PET and iPET14,18,20,. The analysis involved 2646 patients, of which 1483 are HPV-positive (17 studies: 10 mixed and 7 HPV-positive only), 589 are HPV-negative, and 574 have unknown HPV status. Eighteen studies found significant correlations of survival outcomes with pre-PET parameters, most commonly primary or "Total" (combined primary and nodal) metabolic tumour volume and/or total lesional glycolysis. Two studies could not establish significant correlations and both employed SUVmax only. Two studies also could not establish significant correlations when taking into account of the HPV-positive population only. Because of the heterogeneity and lack of standardized methodology, no conclusions on optimal cut-off values can be drawn. Ten studies specifically evaluated HPV-positive patients: five showed positive correlation of pre-PET parameters and survival outcomes, but four of these studies did not include advanced T or N staging in multivariate analysis1,6,15,22, and two studies only showed positive correlations after excluding high risk patients with smoking history7 or adverse CT features22. Two studies found that prePET parameters predicted treatment outcomes only in HPV-negative but not HPV-positive patients10,16. Two studies found that iPET parameters could predict outcomes in HPV-positive patients but not prePET parameters14,18. CONCLUSION The current literature supports high pre-treatment metabolic burden prior to definitive (chemo)radiotherapy can predict poor treatment outcomes for HPV-negative OPC patients. Evidence is conflicting and currently does not support correlation in HPV-positive patients.
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Affiliation(s)
- Peter Lin Fracp
- Department of Nuclear Medicine and PET, Liverpool Hospital, Liverpool, NSW, Australia; South Western Sydney Clinical School, University of New South Wales, NSW, Australia; School of Medicine, Western Sydney University, NSW, Australia.
| | - Lois Holloway
- South Western Sydney Clinical School, University of New South Wales, NSW, Australia; School of Medicine, Western Sydney University, NSW, Australia; Cancer Therapy Centre, Liverpool Hospital, Liverpool, NSW, Australia; Ingham Institute of Applied Medical Research, Liverpool, NSW, Australia
| | - Myo Min Franzcr
- Department of Radiation Oncology, Sunshine Coast University Hospital, Queensland, Australia; Faculty of Science, Health, Education and Engineering, University of Sunshine Coast, Queensland, Australia
| | - Mark Lee Franzcr
- South Western Sydney Clinical School, University of New South Wales, NSW, Australia; Cancer Therapy Centre, Liverpool Hospital, Liverpool, NSW, Australia
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Affiliation(s)
- Gerald A. Dienel
- Department of Neurology University of Arkansas for Medical Sciences Little Rock Arkansas USA
- Department of Cell Biology and Physiology University of New Mexico School of Medicine Albuquerque New Mexico USA
| | - Lisa Gillinder
- Mater Hospital South Brisbane Queensland Australia
- Faculty of Medicine Mater Research Institute, University of Queensland St Lucia Queensland Australia
| | - Aileen McGonigal
- Mater Hospital South Brisbane Queensland Australia
- Faculty of Medicine Mater Research Institute, University of Queensland St Lucia Queensland Australia
| | - Karin Borges
- Faculty of Medicine School of Biomedical Sciences, University of Queensland St Lucia Queensland Australia
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7
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Dienel GA, Gillinder L, McGonigal A, Borges K. Potential new roles for glycogen in epilepsy. Epilepsia 2023; 64:29-53. [PMID: 36117414 PMCID: PMC10952408 DOI: 10.1111/epi.17412] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/15/2022] [Accepted: 09/15/2022] [Indexed: 01/21/2023]
Abstract
Seizures often originate in epileptogenic foci. Between seizures (interictally), these foci and some of the surrounding tissue often show low signals with 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in many epileptic patients, even when there are no radiologically detectable structural abnormalities. Low FDG-PET signals are thought to reflect glucose hypometabolism. Here, we review knowledge about metabolism of glucose and glycogen and oxidative stress in people with epilepsy and in acute and chronic rodent seizure models. Interictal brain glucose levels are normal and do not cause apparent glucose hypometabolism, which remains unexplained. During seizures, high amounts of fuel are needed to satisfy increased energy demands. Astrocytes consume glycogen as an additional emergency fuel to supplement glucose during high metabolic demand, such as during brain stimulation, stress, and seizures. In rodents, brain glycogen levels drop during induced seizures and increase to higher levels thereafter. Interictally, in people with epilepsy and in chronic epilepsy models, normal glucose but high glycogen levels have been found in the presumed brain areas involved in seizure generation. We present our new hypothesis that as an adaptive response to repeated episodes of high metabolic demand, high interictal glycogen levels in epileptogenic brain areas are used to support energy metabolism and potentially interictal neuronal activity. Glycogenolysis, which can be triggered by stress or oxidative stress, leads to decreased utilization of plasma glucose in epileptogenic brain areas, resulting in low FDG signals that are related to functional changes underlying seizure onset and propagation. This is (partially) reversible after successful surgery. Last, we propose that potential interictal glycogen depletion in epileptogenic and surrounding areas may cause energy shortages in astrocytes, which may impair potassium buffering and contribute to seizure generation. Based on these hypotheses, auxiliary fuels or treatments that support glycogen metabolism may be useful to treat epilepsy.
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Affiliation(s)
- Gerald A. Dienel
- Department of NeurologyUniversity of Arkansas for Medical SciencesLittle RockArkansasUSA
- Department of Cell Biology and PhysiologyUniversity of New Mexico School of MedicineAlbuquerqueNew MexicoUSA
| | - Lisa Gillinder
- Mater HospitalSouth BrisbaneQueenslandAustralia
- Faculty of MedicineMater Research Institute, University of QueenslandSt LuciaQueenslandAustralia
| | - Aileen McGonigal
- Mater HospitalSouth BrisbaneQueenslandAustralia
- Faculty of MedicineMater Research Institute, University of QueenslandSt LuciaQueenslandAustralia
| | - Karin Borges
- Faculty of MedicineSchool of Biomedical Sciences, University of QueenslandSt LuciaQueenslandAustralia
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8
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Vijayakumar S, Yang J, Nittala MR, Velazquez AE, Huddleston BL, Rugnath NA, Adari N, Yajurvedi AK, Komanduri A, Yang CC, Duggar WN, Berlin WP, Duszak R, Vijayakumar V. Changing Role of PET/CT in Cancer Care With a Focus on Radiotherapy. Cureus 2022; 14:e32840. [PMID: 36694538 PMCID: PMC9867792 DOI: 10.7759/cureus.32840] [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] [Accepted: 12/22/2022] [Indexed: 12/24/2022] Open
Abstract
Positron emission tomography (PET) integrated with computed tomography (CT) has brought revolutionary changes in improving cancer care (CC) for patients. These include improved detection of previously unrecognizable disease, ability to identify oligometastatic status enabling more aggressive treatment strategies when the disease burden is lower, its use in better defining treatment targets in radiotherapy (RT), ability to monitor treatment responses early and thus improve the ability for early interventions of non-responding tumors, and as a prognosticating tool as well as outcome predicting tool. PET/CT has enabled the emergence of new concepts such as radiobiotherapy (RBT), radioimmunotherapy, theranostics, and pharmaco-radiotherapy. This is a rapidly evolving field, and this primer is to help summarize the current status and to give an impetus to developing new ideas, clinical trials, and CC outcome improvements.
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Affiliation(s)
| | - Johnny Yang
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Mary R Nittala
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | | | | | - Nickhil A Rugnath
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Neha Adari
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Abhay K Yajurvedi
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Abhinav Komanduri
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Claus Chunli Yang
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - William N Duggar
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - William P Berlin
- Radiology, University of Mississippi Medical Center, Jackson, USA
| | - Richard Duszak
- Radiology, University of Mississippi Medical Center, Jackson, USA
| | - Vani Vijayakumar
- Radiology, University of Mississippi Medical Center, Jackson, USA
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9
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Lin YK, Tsai CL, Lin GY, Chou CH, Yang FC. Pathophysiology of Chronic Migraine: Insights from Recent Neuroimaging Research. Curr Pain Headache Rep 2022; 26:843-854. [PMID: 36207509 DOI: 10.1007/s11916-022-01087-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2022] [Indexed: 11/28/2022]
Abstract
PURPOSE OF REVIEW Chronic migraine (CM) is a highly disabling primary headache disorder with a substantial impact on patients' quality of life. Episodic migraine (EM) and CM are dynamic states; CM usually evolves from EM alongside increased headache frequency, comorbidities, and medication overuse, supporting the notion that migraine is a spectrum disorder. This narrative review aims to summarize neuroimaging studies to better understand the pathophysiology of CM. RECENT FINDINGS Positron emission tomography studies have revealed abnormal energy metabolism and metabolic changes in the dorsal rostral pons in individuals with CM, suggesting that this structure has a key role in the pathophysiology of migraine generation and chronification. Magnetic resonance spectroscopy studies have suggested that thalamocortical pathway dysfunction may contribute to migraine chronification, while functional magnetic resonance imaging studies have highlighted that hypothalamic activity may be involved. Recent evidence highlights functional and structural alterations in cortical and subcortical pain-related brain regions in patients with CM. Whether these functional and structural abnormalities of the brain cause migraine chronification or are a consequence of repeated attacks is still debated. In the future, imaging patterns that predict the transformation from EM to CM should be identified.
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Affiliation(s)
- Yu-Kai Lin
- Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Section 2, Cheng-Kung Road, Neihu 114, No. 325, Taipei, Taiwan.,Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Chia-Lin Tsai
- Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Section 2, Cheng-Kung Road, Neihu 114, No. 325, Taipei, Taiwan
| | - Guan-Yu Lin
- Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Section 2, Cheng-Kung Road, Neihu 114, No. 325, Taipei, Taiwan
| | - Chung-Hsing Chou
- Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Section 2, Cheng-Kung Road, Neihu 114, No. 325, Taipei, Taiwan.,Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Fu-Chi Yang
- Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Section 2, Cheng-Kung Road, Neihu 114, No. 325, Taipei, Taiwan. .,Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan.
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10
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Leccisotti L, Gheysens O. Update on PET/CT in autoimmune disorders. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF... 2022; 66:179-181. [PMID: 35612372 DOI: 10.23736/s1824-4785.22.03471-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- Lucia Leccisotti
- Unit of Nuclear Medicine, Department of Diagnostic Imaging, Radiation Oncology and Hematology, IRCCS A. Gemelli University Polyclinic Foundation, Rome, Italy -
- Section of Nuclear Medicine, University Department of Radiological Sciences and Hematology, Sacred Heart Catholic University, Rome, Italy -
| | - Olivier Gheysens
- Department of Nuclear Medicine, Saint-Luc Clinical University and Institute of Clinical and Experimental Research (IREC), Catholic University of Louvain (UCLouvain), Brussels, Belgium
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11
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Han FY, Conboy‐Schmidt L, Rybachuk G, Volk HA, Zanghi B, Pan Y, Borges K. Dietary medium chain triglycerides for management of epilepsy: New data from human, dog, and rodent studies. Epilepsia 2021; 62:1790-1806. [PMID: 34169513 PMCID: PMC8453917 DOI: 10.1111/epi.16972] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 06/07/2021] [Accepted: 06/07/2021] [Indexed: 12/17/2022]
Abstract
Many studies show that glucose metabolism in epileptic brain areas can be impaired. Energy is crucial to maintain normal brain function, including ion and neurotransmitter balances. Energy deficits can lead to disruption of ion gradients, which can trigger neuronal depolarization and generation of seizures. Thus, perturbed metabolic processing of glucose in epileptogenic brain areas indicates a specific nutritional need for people and animals with epilepsy, as they are likely to benefit from auxiliary brain fuels other than glucose. Ketogenic diets provide the ketone bodies acetoacetate and β-hydroxybutyrate, which can be used as auxiliary fuel by the brain. In approximately 50% children and adults with certain types of epilepsy, who can tolerate and maintain these dietary regimens, seizure frequency can be effectively reduced. More recent data demonstrate that addition of medium chain triglycerides (MCTs), which provide the medium chain fatty acids octanoic and decanoic acid, as well as ketone bodies as auxiliary brain energy, can be beneficial in rodent seizure models, and dogs and humans with epilepsy. Here, this evidence is reviewed, including tolerance in 65% of humans, efficacy studies in dogs, possible anticonvulsant mechanisms of actions of MCTs, and specifically decanoic acid as well as metabolic and antioxidant mechanisms. In conclusion, MCTs are a promising adjunct to standard pharmacological treatment for both humans and dogs with epilepsy, as they lack central nervous system side effects found with current antiepileptic drugs. There is now a need for larger clinical trials in children, adults, and dogs to find the ideal composition and doses of MCTs and the types of epilepsy that respond best.
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Affiliation(s)
- Felicity Y. Han
- Faculty of MedicineSchool of Biomedical SciencesUniversity of QueenslandSt. LuciaQueenslandAustralia
| | | | - Galena Rybachuk
- Technical CommunicationsNestlé Purina PetCare EMENABarcelonaSpain
| | - Holger A. Volk
- Department of Small Animal Medicine and SurgeryUniversity of Veterinary MedicineHanoverGermany
| | - Brian Zanghi
- Research and DevelopmentNestlé Purina PetCareSt. LouisMissouriUSA
| | - Yuanlong Pan
- Research and DevelopmentNestlé Purina PetCareSt. LouisMissouriUSA
| | - Karin Borges
- Faculty of MedicineSchool of Biomedical SciencesUniversity of QueenslandSt. LuciaQueenslandAustralia
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12
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Pijl JP, Nienhuis PH, Kwee TC, Glaudemans AWJM, Slart RHJA, Gormsen LC. Limitations and Pitfalls of FDG-PET/CT in Infection and Inflammation. Semin Nucl Med 2021; 51:633-645. [PMID: 34246448 DOI: 10.1053/j.semnuclmed.2021.06.008] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
White blood cells activated by either a pathogen or as part of a systemic inflammatory disease are characterized by high energy consumption and are therefore taking up the glucose analogue PET tracer FDG avidly. It is therefore not surprising that a steadily growing body of research and clinical reports now supports the use of FDG PET/CT to diagnose a wide range of patients with non-oncological diseases. However, using FDG PET/CT in patients with infectious or inflammatory diseases has some limitations and potential pitfalls that are not necessarily as pronounced in oncology FDG PET/CT. Some of these limitations are of a general nature and related to the laborious acquisition of PET images in patients that are often acutely ill, whereas others are more disease-specific and related to the particular metabolism in some of the organs most commonly affected by infections or inflammatory disease. Both inflammatory and infectious diseases are characterized by a more diffuse and less pathognomonic pattern of FDG uptake than oncology FDG PET/CT and the affected organs also typically have some physiological FDG uptake. In addition, patients referred to PET/CT with suspected infection or inflammation are rarely treatment naïve and may have received varying doses of antibiotics, corticosteroids or other immune-modulating drugs at the time of their examination. Combined, this results in a higher rate of false positive FDG findings and also in some cases a lower sensitivity to detect active disease. In this review, we therefore discuss the limitations and pitfalls of FDG PET/CT to diagnose infections and inflammation taking these issues into consideration. Our review encompasses the most commonly encountered inflammatory and infectious diseases in head and neck, in the cardiovascular system, in the abdominal organs and in the musculoskeletal system. Finally, new developments in the field of PET/CT that may help overcome some of these limitations are briefly highlighted.
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Affiliation(s)
- Jordy P Pijl
- Medical Imaging Center, Departments of Radiology, Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen
| | - Pieter H Nienhuis
- Medical Imaging Center, Departments of Radiology, Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen
| | - Thomas C Kwee
- Medical Imaging Center, Departments of Radiology, Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen
| | - Andor W J M Glaudemans
- Medical Imaging Center, Departments of Radiology, Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen
| | - Riemer H J A Slart
- Medical Imaging Center, Departments of Radiology, Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen; Faculty of Science and Technology, Department of Biomedical Photonic Imaging, University of Twente, Enschede
| | - Lars C Gormsen
- Department of Nuclear Medicine & PET Center, Aarhus University Hospital, Aarhus N.
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13
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Abstract
Migraine is a prevalent primary headache disorder and is usually considered as benign. However, structural and functional changes in the brain of individuals with migraine have been reported. High frequency of white matter abnormalities, silent infarct-like lesions, and volumetric changes in both gray and white matter in individuals with migraine compared to controls have been demonstrated. Functional magnetic resonance imaging (MRI) studies found altered connectivity in both the interictal and ictal phase of migraine. MR spectroscopy and positron emission tomography studies suggest abnormal energy metabolism and mitochondrial dysfunction, as well as other metabolic changes in individuals with migraine. In this review, we provide a brief overview of neuroimaging studies that have helped us to characterize some of these changes and discuss their limitations, including small sample sizes and poorly defined control groups. A better understanding of alterations in the brains of patients with migraine could help not only in the diagnosis but may potentially lead to the optimization of a targeted anti-migraine therapy.
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Ross JA, Van Bockstaele EJ. The Locus Coeruleus- Norepinephrine System in Stress and Arousal: Unraveling Historical, Current, and Future Perspectives. Front Psychiatry 2021; 11:601519. [PMID: 33584368 PMCID: PMC7873441 DOI: 10.3389/fpsyt.2020.601519] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/14/2020] [Indexed: 01/03/2023] Open
Abstract
Arousal may be understood on a spectrum, with excessive sleepiness, cognitive dysfunction, and inattention on one side, a wakeful state in the middle, and hypervigilance, panic, and psychosis on the other side. However, historically, the concepts of arousal and stress have been challenging to define as measurable experimental variables. Divergent efforts to study these subjects have given rise to several disciplines, including neurobiology, neuroendocrinology, and cognitive neuroscience. We discuss technological advancements that chronologically led to our current understanding of the arousal system, focusing on the multifaceted nucleus locus coeruleus. We share our contemporary perspective and the hypotheses of others in the context of our current technological capabilities and future developments that will be required to move forward in this area of research.
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Affiliation(s)
- Jennifer A. Ross
- Department of Pharmacology and Physiology, College of Medicine, Drexel University, Philadelphia, PA, United States
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15
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Wang Z, Mascarenhas C, Jia X. Positron Emission Tomography After Ischemic Brain Injury: Current Challenges and Future Developments. Transl Stroke Res 2020; 11:628-642. [PMID: 31939060 PMCID: PMC7347441 DOI: 10.1007/s12975-019-00765-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 11/22/2019] [Accepted: 12/04/2019] [Indexed: 12/19/2022]
Abstract
Positron emission tomography (PET) is widely used in clinical and animal studies, along with the development of diverse tracers. The biochemical characteristics of PET tracers may help uncover the pathophysiological consequences of cardiac arrest (CA) and ischemic stroke, which include cerebral ischemia and reperfusion, depletion of oxygen and glucose, and neuroinflammation. PubMed was searched for studies of the application of PET for "cardiac arrest," "ischemic stroke," and "targeted temperature management." Available studies were included and classified according to the biochemical properties involved and metabolic processes of PET tracers, and were summarized. The mechanisms of ischemic brain injuries were investigated by PET with various tracers to elucidate the pathological process from the initial decrease of cerebral blood flow (CBF) to the subsequent abnormalities in energy and oxygen metabolism, to the monitoring of inflammation. In general, the trends of cerebral blood flow and oxygen metabolism after ischemic attack are not unidirectional but closely related to the time point of injury and recovery. Glucose metabolism after injury showed significant differences in different brain regions whereas global cerebral metabolic rate of glucose (CMRglc) declined. PET monitoring of neuroinflammation shows comparable efficacy to immunostaining. The technology of PET targeting in brain metabolism and the development of tracers provide new tools to track and evaluate the brain's pathological changes after ischemic brain injury. Despite no existing evidence for an available PET-based prediction method, discoveries of new tracers are expected to provide more possibilities for the whole field.
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Affiliation(s)
- Zhuoran Wang
- Department of Critical Care Medicine, Zhongnan Hospital of Wuhan University, Wuhan, 43007, China
- Department of Neurosurgery, University of Maryland School of Medicine, 10 South Pine Street, MSTF Building 823, Baltimore, MD, 21201, USA
| | - Conrad Mascarenhas
- Department of Neurosurgery, University of Maryland School of Medicine, 10 South Pine Street, MSTF Building 823, Baltimore, MD, 21201, USA
| | - Xiaofeng Jia
- Department of Neurosurgery, University of Maryland School of Medicine, 10 South Pine Street, MSTF Building 823, Baltimore, MD, 21201, USA.
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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16
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A critical review of radiotracers in the positron emission tomography imaging of traumatic brain injury: FDG, tau, and amyloid imaging in mild traumatic brain injury and chronic traumatic encephalopathy. Eur J Nucl Med Mol Imaging 2020; 48:623-641. [DOI: 10.1007/s00259-020-04926-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 06/11/2020] [Indexed: 12/14/2022]
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17
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Manzanera OM, Meles SK, Leenders KL, Renken RJ, Pagani M, Arnaldi D, Nobili F, Obeso J, Oroz MR, Morbelli S, Maurits NM. Scaled Subprofile Modeling and Convolutional Neural Networks for the Identification of Parkinson’s Disease in 3D Nuclear Imaging Data. Int J Neural Syst 2019; 29:1950010. [DOI: 10.1142/s0129065719500102] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Over the last years convolutional neural networks (CNNs) have shown remarkable results in different image classification tasks, including medical imaging. One area that has been less explored with CNNs is Positron Emission Tomography (PET). Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) is a PET technique employed to obtain a representation of brain metabolic function. In this study we employed 3D CNNs in FDG-PET brain images with the purpose of discriminating patients diagnosed with Parkinson’s disease (PD) from controls. We employed Scaled Subprofile Modeling using Principal Component Analysis as a preprocessing step to focus on specific brain regions and limit the number of voxels that are used as input for the CNNs, thereby increasing the signal-to-noise ratio in our data. We performed hyperparameter optimization on three CNN architectures to estimate the classification accuracy of the networks on new data. The best performance that we obtained was [Formula: see text] and area under the receiver operating characteristic curve [Formula: see text] on the test set. We believe that, with larger datasets, PD patients could be reliably distinguished from controls by FDG-PET scans alone and that this technique could be applied to more clinically challenging tasks, like the differential diagnosis of neurological disorders with similar symptoms, such as PD, Progressive Supranuclear Palsy (PSP) and Multiple System Atrophy (MSA).
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Affiliation(s)
- Octavio Martinez Manzanera
- Department of Neurology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - Sanne K. Meles
- Department of Neurology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - Klaus L. Leenders
- Department of Neurology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands
| | - Remco J. Renken
- Faculty of Medical Sciences, University Medical Center Groningen, University of Groningen, A. Deusinglaan 1, Groningen, The Netherlands
| | - Marco Pagani
- Institute of Cognitive Sciences and Technologies, Consiglio Nazionale delle Ricerche, via S. Martino della Battaglia, 44-00185 Rome, Italy
- Department of Nuclear Medicine, Karolinska University Hospital, Huddinge, SE-141 86, Stockholm, Sweden
- Department of Nuclear Medicine, University Medical Center Groningen, University of Groningen, Hanzeplein 1,9713 GZ Groningen, The Netherlands
| | - Dario Arnaldi
- Department of Neuroscience, Rehabilitation, Opthalmology, Genetics and Maternal and Child Science (DINOGMI), University of Genoa Largo Paolo Daneo 3, 16132 Genoa, Italy
- IRCCS AOU San Martino — IST, Largo R. Benzi 10, 16132 Genoa, Italy
| | - Flavio Nobili
- Department of Neuroscience, Rehabilitation, Opthalmology, Genetics and Maternal and Child Science (DINOGMI), University of Genoa Largo Paolo Daneo 3, 16132 Genoa, Italy
- IRCCS AOU San Martino — IST, Largo R. Benzi 10, 16132 Genoa, Italy
| | - Jose Obeso
- CINAC, HM Puerta del Sur, Avda. de Carlos V 70, 28938 Móstoles (Madrid), Spain
- CEU Universidad San Pablo, C/Julián Romea 18, 28003 Madrid, Spain
- CIBERNED, Instituto Carlos III, C/Valderrebollo 5, 28031 Madrid, Spain
| | - Maria Rodriguez Oroz
- Department of Neurosciences, Biodonostia Health Research Institute, Begiristain Doktorea Pasealekua, 20014 Donostia-San Sebastián, Guipúzcoa, Spain
| | - Silvia Morbelli
- IRCCS AOU San Martino — IST, Largo R. Benzi 10, 16132 Genoa, Italy
- Nuclear Medicine Unit, Department of Health Sciences (DISSAL), University of Genoa via A. Pastore 1, 16132 Genoa, Italy
| | - Natasha M. Maurits
- Department of Neurology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
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18
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Xu J, Xie S, Zhang X, Tao W, Yang J, Zhao Z, Weng F, Huang Q, Yi F, Peng Q. A preclinical PET detector constructed with a monolithic scintillator ring. Phys Med Biol 2019; 64:155009. [PMID: 31239424 PMCID: PMC6692080 DOI: 10.1088/1361-6560/ab2ca4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
This paper presents a unique preclinical positron emission tomography (PET) detector constructed with a monolithic scintillator ring (MSR) and two rings of silicon photomultipliers (SiPM). The inner diameter, outer diameter and length of the MSR were 48.5 mm, 58.5 mm, and 25.1 mm, respectively. The two SiPM rings, constructed with 46 SiPMs, were air-coupled to the two ends of the MSR detector. The center of gravity (COG) and artificial neural network (ANN) methods were adapted to decode the positions of the gamma interactions in the circumferential (θ) and axial (Z) directions, respectively. Collimating systems, consisting of a tungsten collimator and a high-precision displacement and rotating platform, were constructed to assess the decoding accuracies of the MSR detector in both θ and Z directions. The average intrinsic full-width half maximums (FWHMs) and mean absolute errors (MAEs) of the decoding accuracies were 0.94 mm and 0.33 mm in the circumferential direction, 2.45 mm and 1.08 mm in the axial direction. An energy resolution of 10.7% was measured at 511 keV. The scintillating photons generated by a pair of coincidence gamma photons overlap with each other, and cause circumferential parallax errors in the lines of response (LOR). The experimental results show that the average FWHM errors in the θ direction increased slightly from 0.94 mm to 1.14 mm when Δθ of the two single events was larger than 70°. The imaging performance of the MSR detector was also initially assessed with a Derenzo phantom filled with 18F-FDG. The rods with a diameter larger than 1.2 mm can be resolved. The energy resolutions were 12.3% at 511 keV (single events), and 11.4% at 1022 keV (coincidence events). We concluded that it is feasible to construct the high-performance preclinical PET scanners using one or multiple MSR detectors.
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Affiliation(s)
- Jianfeng Xu
- State Key Lab of Digital Manufacturing Equipment & Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Siwei Xie
- State Key Lab of Digital Manufacturing Equipment & Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
- Department of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Xi Zhang
- State Key Lab of Digital Manufacturing Equipment & Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Weijie Tao
- School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai 200025, China
| | - Jingwu Yang
- State Key Lab of Digital Manufacturing Equipment & Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Zhixiang Zhao
- School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai 200025, China
| | - Fenghua Weng
- School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai 200025, China
| | - Qiu Huang
- School of Biomedical Engineering, Shanghai Jiaotong University, Shanghai 200025, China
| | - Fei Yi
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Qiyu Peng
- Department of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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Samal J, Rebelo AL, Pandit A. A window into the brain: Tools to assess pre-clinical efficacy of biomaterials-based therapies on central nervous system disorders. Adv Drug Deliv Rev 2019; 148:68-145. [PMID: 30710594 DOI: 10.1016/j.addr.2019.01.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 01/04/2019] [Accepted: 01/28/2019] [Indexed: 12/13/2022]
Abstract
Therapeutic conveyance into the brain is a cardinal requirement for treatment of diverse central nervous system (CNS) disorders and associated pathophysiology. Effectual shielding of the brain by the blood-brain barrier (BBB) sieves out major proportion of therapeutics with the exception of small lipophilic molecules. Various nano-delivery systems (NDS) provide an effective solution around this obstacle owing to their small size and targeting properties. To date, these systems have been used for several pre-clinical disease models including glioma, neurodegenerative diseases and psychotic disorders. An efficacy screen for these systems involves a test battery designed to probe into the multiple facets of therapeutic delivery. Despite their wide application in redressing various disease targets, the efficacy evaluation strategies for all can be broadly grouped into four modalities, namely: histological, bio-imaging, molecular and behavioural. This review presents a comprehensive insight into all of these modalities along with their strengths and weaknesses as well as perspectives on an ideal design for a panel of tests to screen brain nano-delivery systems.
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Affiliation(s)
- Juhi Samal
- CÚRAM, Centre for Research in Medical Devices, National University of Ireland Galway, Galway, Ireland
| | - Ana Lucia Rebelo
- CÚRAM, Centre for Research in Medical Devices, National University of Ireland Galway, Galway, Ireland
| | - Abhay Pandit
- CÚRAM, Centre for Research in Medical Devices, National University of Ireland Galway, Galway, Ireland.
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20
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Mukku SSR, Sivakumar PT, Nagaraj C, Mangalore S, Harbishettar V, Varghese M. Clinical utility of 18F-FDG-PET/MRI brain in dementia: Preliminary experience from a geriatric clinic in South India. Asian J Psychiatr 2019; 44:99-105. [PMID: 31336358 DOI: 10.1016/j.ajp.2019.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 07/04/2019] [Accepted: 07/05/2019] [Indexed: 12/30/2022]
Abstract
BACKGROUND 18F-FDG-PET is a potential sensitive biomarker indicating neuronal damage. 18F-FDG-PET has proven to be useful in subtyping dementia. Utility of simultaneous 18F-FDG-PET and MRI-brain was investigated in the evaluation of dementia in this facility. METHOD All case notes of patients who underwent 18 F-FDG-PET/MRI brain attending the Geriatric Clinic for 18 month period between January 2017 and June 2018 were retrospectively reviewed. Their socio-demographic details, MRI-brain finding, 18F- FDG-PET findings and comorbid illnesses were studied. RESULTS A total of 21 patients underwent 18F-FDG-PET/MRI brain during study period. The mean age was 61.23, SD-8.6 years (range: 36-75 years). Among them 5 (23.8%) had Mild Cognitive Impairment (MCI) and 16 (76.2%) had dementia. Majority of patients had early onset cognitive decline (76.2%). Based on the pattern of hypometabolism, the MCI group had one patient each indicative of AD, Semantic-Frontotemporal dementia (Semantic-FTD), mixed Alzheimer's dementia (AD + FTD) and two patients had patterns suggestive of Behaviour Variant of FTD (Bv-FTD). In Dementia group the pattern of hypometabolism was indicative of Bv-FTD in seven, AD in four, Posterior Cortical Atrophy (PCA) in one, Semantic-FTD in one, Mixed AD-Diffuse Lewy Body Dementia (DLBD) in one and no specific pattern in two patients. MRI and 18 F-FDG-PET brain had concordance in 9 (56.26%) patients. DISCUSSION 18F-FDG-PET/MRI helped in overall clinical diagnosis and management in 19 (90.5%) patients especially with early onset dementia. In MCI group it indicated underlying aetiology and in dementia group it helped in subtyping. CONCLUSION The study supports the role of 18F-FDG-PET/MRI as an emerging diagnostic tool to assist in dementia evaluation in India.
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Affiliation(s)
- Shiva Shanker Reddy Mukku
- Geriatric Clinic & Services, Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, 560029, India.
| | - Palanimuthu Thangaraju Sivakumar
- Geriatric Clinic & Services, Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, 560029, India.
| | - Chandana Nagaraj
- Department of Neuroimaging and interventional Radiology, National Institute of Mental Health and Neurosciences, Bangalore, 560029, India.
| | - Sandhya Mangalore
- Department of Neuroimaging and interventional Radiology, National Institute of Mental Health and Neurosciences, Bangalore, 560029, India.
| | - Vijaykumar Harbishettar
- Geriatric Clinic & Services, Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, 560029, India.
| | - Mathew Varghese
- Geriatric Clinic & Services, Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bangalore, 560029, India.
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21
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Acuff SN, Mathotaarachchi S, Zukotynski K, Osborne D, Subramaniam R. Clinical and Technical Considerations for Brain PET Imaging for Dementia. J Nucl Med Technol 2019; 48:5-8. [PMID: 31182663 DOI: 10.2967/jnmt.118.220087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 05/13/2019] [Indexed: 11/16/2022] Open
Abstract
The number of cases of dementia has dramatically increased over the last decade. Imaging of the brain with PET has been used for many years, but in the past decade the radiopharmaceuticals and technology available for imaging dementia have vastly improved. In recent years, the U.S. Food and Drug Administration has approved 3 PET radiopharmaceuticals for detecting amyloid in brain, and tau PET radiopharmaceuticals are being investigated in clinical trials for use in dementia imaging. This paper will discuss different forms of dementia that can be imaged with PET, review common radiopharmaceuticals used for imaging dementia, and provide technical recommendations for performing the studies.
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Affiliation(s)
- Shelley N Acuff
- Department of Radiology, University of Tennessee Medical Center, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee
| | | | - Katherine Zukotynski
- Departments of Medicine and Radiology, McMaster University, Hamilton, Ontario, Canada; and
| | - Dustin Osborne
- Department of Radiology, University of Tennessee Medical Center, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee
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22
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Spadoni AD, Huang M, Simmons AN. Emerging Approaches to Neurocircuits in PTSD and TBI: Imaging the Interplay of Neural and Emotional Trauma. Curr Top Behav Neurosci 2019; 38:163-192. [PMID: 29285732 PMCID: PMC8896198 DOI: 10.1007/7854_2017_35] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) commonly co-occur in general and military populations and have a number of overlapping symptoms. While research suggests that TBI is risk factor for PTSD and that PTSD may mediate TBI-related outcomes, the mechanisms of these relationships are not well understood. Neuroimaging may help elucidate patterns of neurocircuitry both specific and common to PTSD and TBI and thus help define the nature of their interaction, refine diagnostic classification, and may potentially yield opportunities for targeted treatments. In this review, we provide a summary of some of the most common and the most innovative neuroimaging approaches used to characterize the neural circuits associated with PTSD, TBI, and their comorbidity. We summarize the state of the science for each disorder and describe the few studies that have explicitly attempted to characterize the neural substrates of their shared and dissociable influence. While some promising targets in the medial frontal lobes exist, there is not currently a comprehensive understanding of the neurocircuitry mediating the interaction of PTSD and TBI. Future studies should exploit innovative neuroimaging approaches and longitudinal designs to specifically target the neural mechanisms driving PTSD-TBI-related outcomes.
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Affiliation(s)
- Andrea D Spadoni
- Research Service, VA San Diego Healthcare System, San Diego, CA, USA.
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA.
| | - Mingxiong Huang
- Radiology and Research Services, VA San Diego Healthcare System, San Diego, CA, USA
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Alan N Simmons
- Research Service, VA San Diego Healthcare System, San Diego, CA, USA
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
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23
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Vaillancourt DE. What Would Dr. James Parkinson Think Today? Tau and Other Imaging Possibilities in Parkinson's Disease. Mov Disord 2018; 32:805-806. [PMID: 28597559 DOI: 10.1002/mds.27075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 05/25/2017] [Indexed: 11/10/2022] Open
Affiliation(s)
- David E Vaillancourt
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA.,Center for Movement Disorders and Neurorestoration, University of Florida, Gainesville, Florida, USA.,Department of Biomedical Engineering, University of Florida, Gainesville, Florida, USA
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24
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Heckmann JG, Niedermeier W, Büchner M, Scher B. Distinctive FDG-PET/CT Findings in Acute Neurological Hospital Care. Neurohospitalist 2018; 9:93-99. [PMID: 30915187 DOI: 10.1177/1941874418805339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
A compilation of 6 distinctive 18F-fluorodeoxyglucose positron emission tomography (PET) combined with computed tomography (CT) findings in the acute setting of neurohospital care is presented. In case 1, PET/CT allowed the final diagnosis of circumscribed ischemic infarction by demonstrating a clear pattern of luxury perfusion. In case 2, diagnosis of thalamic abscess was made, whereby PET/CT demonstrated an empty zone. Hypermetabolic enlarged hilar lymph nodes and hypermetabolic spinal lumbar roots in PET/CT led to the diagnosis of neurosarcoidosis in case 3. In case 4, a hypermetabolic brain focus in PET/CT identified the seizure focus in epilepsia partialis continua. A cerebral hemispheric hypometabolism in PET/CT in case 5 supported the diagnosis of Creutzfeldt-Jakob disease, which initially mimicked acute stroke. In case 6, PET/CT detected infective endocarditis as a source of multiple cerebral ischemic lesions. In conclusion, PET/CT can contribute importantly to find the correct diagnosis in acute neurohospital patients.
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Affiliation(s)
| | - Wolfgang Niedermeier
- Department of Radiology and Nuclear Medicine, Municipal Hospital Waid, Zurich, Switzerland
| | - Markus Büchner
- Department of Nuclear Medicine, Municipal Hospital Landshut, Germany
| | - Bernhard Scher
- Department of Nuclear Medicine, Municipal Hospital Landshut, Germany
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25
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Rizzolatti G, Fabbri‐Destro M, Caruana F, Avanzini P. System neuroscience: Past, present, and future. CNS Neurosci Ther 2018; 24:685-693. [PMID: 29924477 PMCID: PMC6490004 DOI: 10.1111/cns.12997] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 05/28/2018] [Accepted: 05/29/2018] [Indexed: 01/08/2023] Open
Abstract
In this review, we discuss first the anatomical and lesion studies that allowed the localization of fundamental functions in the cerebral cortex of primates including humans. Subsequently, we argue that the years from the end of the Second World War until the end of the last century represented the "golden age" of system neuroscience. In this period, the mechanisms-not only the localization-underlying sensory, and in particular visual functions were described, followed by those underlying cognitive functions and housed in temporal, parietal, and premotor areas. At the end of the last century, brain imaging techniques were developed that allowed the assessment of the functions of different cortical areas in a more precise and sophisticated way. However, brain imaging tells little about the neural mechanisms underlying functions. Furthermore, the brain imaging suffers from 3 major problems: time is absent, the data are merely correlative and the testing is often not ecological. We conclude our review discussing the possibility that these pitfalls might be overcome by using intracortical recordings (eg stereo-EEG), which have millisecond time resolution, allow direct electrical stimulation of specific sites, and finally enable to study patients while freely moving.
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Affiliation(s)
- Giacomo Rizzolatti
- Istituto di NeuroscienzeConsiglio Nazionale delle RicercheParmaItaly
- Dipartimento di Medicina e ChirurgiaUniversità degli Studi di ParmaParmaItaly
| | | | - Fausto Caruana
- Dipartimento di Medicina e ChirurgiaUniversità degli Studi di ParmaParmaItaly
| | - Pietro Avanzini
- Istituto di NeuroscienzeConsiglio Nazionale delle RicercheParmaItaly
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26
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Molecular imaging in dementia: Past, present, and future. Alzheimers Dement 2018; 14:1522-1552. [DOI: 10.1016/j.jalz.2018.06.2855] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 06/02/2018] [Accepted: 06/03/2018] [Indexed: 12/14/2022]
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27
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Vigneswaran H, Abhyankar N, Kocjancic E. Using Advanced Imaging Including MRI to Detect Voiding Dysfunction in Neurogenic Bladder and Fowler Syndrome. CURRENT BLADDER DYSFUNCTION REPORTS 2017. [DOI: 10.1007/s11884-017-0453-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Palacios JM, Mengod G. Receptor visualization and the atomic bomb. A historical account of the development of the chemical neuroanatomy of receptors for neurotransmitters and drugs during the Cold War. J Chem Neuroanat 2017; 88:76-112. [PMID: 28755996 DOI: 10.1016/j.jchemneu.2017.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 07/13/2017] [Indexed: 01/24/2023]
Abstract
This is a historical account of how receptors for neurotransmitters and drugs got to be seen at the regional, cellular, and subcellular levels in brain, in the years going from the end of the World War II until the collapse of the Soviet Union, the Cold War (1945-1991). The realization in the US of the problem of mental health care, as a consequence of the results of medical evaluation for military service during the war, let the US Government to act creating among other things the National Institute for Mental Health (NIMH). Coincident with that, new drug treatments for these disorders were introduced. War science also created an important number of tools and instruments, such as the radioisotopes, that played a significant role in the development of our story. The scientific context was marked by the development of Biochemistry, Molecular Biology and the introduction in the early 80's of the DNA recombinant technologies. The concepts of chemical neurotransmission in the brain and of receptors for drugs and transmitters, although proposed before the war, where not generally accepted. Neurotransmitters were identified and the mechanisms of biosynthesis, storage, release and termination of action by mechanisms such as reuptake, elucidated. Furthermore, the synapse was seen with the electron microscope and more important for our account, neurons and their processes visualized in the brain first by fluorescence histochemistry, then using radioisotopes and autoradiography, and later by immunohistochemistry (IHC), originating the Chemical Neuroanatomy. The concept of chemical neurotransmission evolved from the amines, expanded to excitatory and inhibitory amino acids, then to neuropeptides and finally to gases and other "atypical" neurotransmitters. In addition, coexpression of more than one transmitter in a neuron, changed the initial ideas of neurotransmission. The concept of receptors for these and other messengers underwent a significant evolution from an abstract chemical concept to their physical reality as gene products. Important steps were the introduction in the 70's of radioligand binding techniques and the cloning of receptor genes in the 80's. Receptors were first visualized using radioligands and autoradiography, and analyzed with the newly developed computer-assisted image analysis systems. Using Positron Emission Tomography transmitters and receptors were visualized in living human brain. The cloning of receptor genes allowed the use of in situ hybridization histochemistry and immunohistochemistry to visualize with the light and electron microscopes the receptor mRNAs and proteins. The results showed the wide heterogeneity of receptors and the diversity of mode of signal transmission, synaptic and extra-synaptic, again radically modifying the early views of neurotransmission. During the entire period the interplay between basic science and Psychopharmacology and Psychiatry generated different transmitter or receptor-based theories of brain drug action. These concepts and technologies also changed the way new drugs were discovered and developed. At the end of the period, a number of declines in these theories, the use of certain tools and the ability to generate new diagnostics and treatments, the end of an era and the beginning of a new one in the research of how the brain functions.
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Affiliation(s)
| | - G Mengod
- IIBB-CSIC, IDIBAPS, CIBERNED, Barcelona, Spain
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Brady SL, Shulkin BL. Dose optimization: a review of CT imaging for PET attenuation correction. Clin Transl Imaging 2017. [DOI: 10.1007/s40336-017-0232-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Schmidtlein CR, Turner JN, Thompson MO, Mandal KC, Häggström I, Zhang J, Humm JL, Feiglin DH, Krol A. Initial performance studies of a wearable brain positron emission tomography camera based on autonomous thin-film digital Geiger avalanche photodiode arrays. J Med Imaging (Bellingham) 2016; 4:011003. [PMID: 27921074 DOI: 10.1117/1.jmi.4.1.011003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 10/20/2016] [Indexed: 11/14/2022] Open
Abstract
Using analytical and Monte Carlo modeling, we explored performance of a lightweight wearable helmet-shaped brain positron emission tomography (PET), or BET camera, based on thin-film digital Geiger avalanche photodiode arrays with Lutetium-yttrium oxyorthosilicate (LYSO) or [Formula: see text] scintillators for imaging in vivo human brain function of freely moving and acting subjects. We investigated a spherical cap BET and cylindrical brain PET (CYL) geometries with 250-mm diameter. We also considered a clinical whole-body (WB) LYSO PET/CT scanner. The simulated energy resolutions were 10.8% (LYSO) and 3.3% ([Formula: see text]), and the coincidence window was set at 2 ns. The brain was simulated as a water sphere of uniform F-18 activity with a radius of 100 mm. We found that BET achieved [Formula: see text] better noise equivalent count (NEC) performance relative to the CYL and [Formula: see text] than WB. For 10-mm-thick [Formula: see text] equivalent mass systems, LYSO (7-mm thick) had [Formula: see text] higher NEC than [Formula: see text]. We found that [Formula: see text] scintillator crystals achieved [Formula: see text] full-width-half-maximum spatial resolution without parallax errors. Additionally, our simulations showed that LYSO generally outperformed [Formula: see text] for NEC unless the timing resolution for [Formula: see text] was considerably smaller than that presently used for LYSO, i.e., well below 300 ps.
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Affiliation(s)
- Charles R Schmidtlein
- Memorial Sloan Kettering Cancer Center , Department of Medical Physics, 1250 First Avenue, New York, New York 10065, United States
| | - James N Turner
- State University of New York at Binghamton , Department of Small Scale Systems, Vestal Parkway East, P.O. Box 6000, Binghamton, New York 13902, United States
| | - Michael O Thompson
- Cornell University , Department of Materials Science and Engineering, 328 Bard Hall, Ithaca, New York 14853-1501, United States
| | - Krishna C Mandal
- University of South Carolina , Department of Electrical Engineering, Main Street, Swearingen Engineering Building 301, Columbia, South Carolina 29208, United States
| | - Ida Häggström
- Memorial Sloan Kettering Cancer Center , Department of Medical Physics, 1250 First Avenue, New York, New York 10065, United States
| | - Jiahan Zhang
- State University of New York Upstate Medical University , Department of Radiology, Syracuse, New York 13210, United States
| | - John L Humm
- Memorial Sloan Kettering Cancer Center , Department of Medical Physics, 1250 First Avenue, New York, New York 10065, United States
| | - David H Feiglin
- State University of New York Upstate Medical University , Department of Radiology, Syracuse, New York 13210, United States
| | - Andrzej Krol
- State University of New York Upstate Medical University, Department of Radiology, Syracuse, New York 13210, United States; State University of New York Upstate Medical University, Department of Pharmacology, 750 E. Adams Street, Syracuse, New York 13210, United States
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Poutiainen P, Jaronen M, Quintana FJ, Brownell AL. Precision Medicine in Multiple Sclerosis: Future of PET Imaging of Inflammation and Reactive Astrocytes. Front Mol Neurosci 2016; 9:85. [PMID: 27695400 PMCID: PMC5023680 DOI: 10.3389/fnmol.2016.00085] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Accepted: 08/30/2016] [Indexed: 12/29/2022] Open
Abstract
Non-invasive molecular imaging techniques can enhance diagnosis to achieve successful treatment, as well as reveal underlying pathogenic mechanisms in disorders such as multiple sclerosis (MS). The cooperation of advanced multimodal imaging techniques and increased knowledge of the MS disease mechanism allows both monitoring of neuronal network and therapeutic outcome as well as the tools to discover novel therapeutic targets. Diverse imaging modalities provide reliable diagnostic and prognostic platforms to better achieve precision medicine. Traditionally, magnetic resonance imaging (MRI) has been considered the golden standard in MS research and diagnosis. However, positron emission tomography (PET) imaging can provide functional information of molecular biology in detail even prior to anatomic changes, allowing close follow up of disease progression and treatment response. The recent findings support three major neuroinflammation components in MS: astrogliosis, cytokine elevation, and significant changes in specific proteins, which offer a great variety of specific targets for imaging purposes. Regardless of the fact that imaging of astrocyte function is still a young field and in need for development of suitable imaging ligands, recent studies have shown that inflammation and astrocyte activation are related to progression of MS. MS is a complex disease, which requires understanding of disease mechanisms for successful treatment. PET is a precise non-invasive imaging method for biochemical functions and has potential to enhance early and accurate diagnosis for precision therapy of MS. In this review we focus on modulation of different receptor systems and inflammatory aspect of MS, especially on activation of glial cells, and summarize the recent findings of PET imaging in MS and present the most potent targets for new biomarkers with the main focus on experimental MS research.
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Affiliation(s)
- Pekka Poutiainen
- Athinoula A Martinos Biomedical Imaging Center, Department of Radiology, Massachusetts General Hospital, Harvard Medical SchoolCharlestown, MA, USA
| | - Merja Jaronen
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical SchoolBoston, MA, USA
| | - Francisco J. Quintana
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical SchoolBoston, MA, USA
| | - Anna-Liisa Brownell
- Athinoula A Martinos Biomedical Imaging Center, Department of Radiology, Massachusetts General Hospital, Harvard Medical SchoolCharlestown, MA, USA
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Sundman M, Doraiswamy PM, Morey RA. Neuroimaging assessment of early and late neurobiological sequelae of traumatic brain injury: implications for CTE. Front Neurosci 2015; 9:334. [PMID: 26441507 PMCID: PMC4585087 DOI: 10.3389/fnins.2015.00334] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 09/04/2015] [Indexed: 12/14/2022] Open
Abstract
Traumatic brain injury (TBI) has been increasingly accepted as a major external risk factor for neurodegenerative morbidity and mortality. Recent evidence indicates that the resultant chronic neurobiological sequelae following head trauma may, at least in part, contribute to a pathologically distinct disease known as Chronic Traumatic Encephalopathy (CTE). The clinical manifestation of CTE is variable, but the symptoms of this progressive disease include impaired memory and cognition, affective disorders (i.e., impulsivity, aggression, depression, suicidality, etc.), and diminished motor control. Notably, mounting evidence suggests that the pathology contributing to CTE may be caused by repetitive exposure to subconcussive hits to the head, even in those with no history of a clinically evident head injury. Given the millions of athletes and military personnel with potential exposure to repetitive subconcussive insults and TBI, CTE represents an important public health issue. However, the incidence rates and pathological mechanisms are still largely unknown, primarily due to the fact that there is no in vivo diagnostic tool. The primary objective of this manuscript is to address this limitation and discuss potential neuroimaging modalities that may be capable of diagnosing CTE in vivo through the detection of tau and other known pathological features. Additionally, we will discuss the challenges of TBI research, outline the known pathology of CTE (with an emphasis on Tau), review current neuroimaging modalities to assess the potential routes for in vivo diagnosis, and discuss the future directions of CTE research.
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Affiliation(s)
- Mark Sundman
- Duke-UNC Brain Imaging and Analysis Center, Duke University Medical Center Durham, NC, USA
| | - P Murali Doraiswamy
- Department of Psychiatry, Duke University Medical Center Durham, NC, USA ; Duke Institute for Brain Sciences, Duke University Medical Center Durham, NC, USA
| | - Rajendra A Morey
- Duke-UNC Brain Imaging and Analysis Center, Duke University Medical Center Durham, NC, USA
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Janero DR. Medications development for substance-use disorders: contextual influences (dis)incentivizing pharmaceutical-industry positioning. Expert Opin Drug Discov 2014; 9:1265-79. [PMID: 25162124 DOI: 10.1517/17460441.2014.951631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
INTRODUCTION The significant contribution of substance-use disorders (SUDs) to the global-disease burden and associated unmet medical needs has not engendered a commensurate level of pharma-industry research and development (R&D) for novel SUD therapeutics invention. Analysis of contextual factors shaping this position suggests potential routes toward incentivizing R&D commitment for that purpose. AREAS COVERED This article considers multiple primary factors that have consorted to disincentivize pharma industry's operating in the SUD space: ill-understood pathology; variegated treatments and patient profiles; involved clinical trials; and - with particular reference to SUDs-negative cultural/business stigmas and shallow commercial precedent. Industry incentivization for SUD drug innovation requires progress on several fronts, including: translational experimental data and systems; personalized, holistic SUD treatment approaches; interactions among pharma, nonindustry constituencies, and the medical profession with vested interests in countering negative stereotypes and expanding SUD treatment options; and public-private alliances focused on improving SUD pharmacotherapy. EXPERT OPINION Given the well-entrenched business stance whereby the prospect of future profits in major markets largely determines drug-company R&D investment trajectory, strategic initiatives offering substantial reductions in the risks and opportunity (i.e., time and money) costs associated with SUD drug discovery are likely to be the most potent drivers for encouraging mainstream industry positioning in this therapeutic area. Such initiatives could originate from front-loaded R&D operational and back-loaded patent, regulatory, marketing and health-care policy reforms. These may be too involved and protracted for the turbulent pharmaceutical industry to entertain amid its recent retrenchment from psychiatric/CNS diseases and intense pressures to increase productivity and shareholder value.
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Affiliation(s)
- David R Janero
- Northeastern University, Bouvé College of Health Sciences, Center for Drug Discovery, Department of Pharmaceutical Sciences, Health Sciences Entrepreneurs , 360 Huntington Avenue, 116 Mugar Life Sciences Hall, Boston, MA 02115-5000 , USA +1 617 373 2208 ; +1 617 373 7493 ;
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Badakhshi H, Graf R, Prasad V, Budach V. The impact of 18 F-FET PET-CT on target definition in image-guided stereotactic radiotherapy in patients with skull base lesions. Cancer Imaging 2014; 14:25. [PMID: 25608761 PMCID: PMC4331830 DOI: 10.1186/1470-7330-14-25] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Accepted: 05/30/2014] [Indexed: 02/01/2023] Open
Abstract
Background 18 F-fluoro-ethyl-tyrosine PET is gaining more indications in the field of oncology. We investigated the potentials of usage of FET-PET/CT in addition to MRI for definition of gross tumor volume (GTV) in stereotactic radiotherapy of lesions of skull base. Methods We included in a prospective setting 21 cases. An MRI was performed, completed by FET PET/CT. Different GTV’s were defined based on respective imaging tools: 1. GTVMRI, 2. GTV MRI /CT, 3. GTV composit (1 + 2), and GTVPET = GTV Boost. Lesions could be visualised by MRI and FET-PET/CT in all patients. Results FET tracer enhancement was found in all cases. Skull base infiltration by these lesions was observed by MRI, CT (PET/CT) and FET-PET (PET/CT) in all patients. Totally, brain tissue infiltration was seen in 10 patients. While, in 7 (out 10) cases, MRI and CT (from PET/CT) were indicating brain infiltration, FET-PET could add additional information regarding infiltrative behaviour: in 3 (out 10) patients, infiltration of the brain was displayed merely in FET-PET. An enlargement of GTVMRI/CT due to the FET-PET driven information, which revealed GTVcomposite , was necessary in 7 cases,. This enlargement was significant by definition (> 10% of GTVMRI/CT). The mean PET-effect on GTV counted for 1 ± 4 cm3. The restricted boost fields were based mainly on the GTVPET volume. In mean, about 8.5 cm3 of GTVMRI/CT, which showed no FET uptake, were excluded from target volume. GTVboost driven by only-PET-activity, was in mean by 33% smaller than the initial large treatment field, GTVcomposite, for those cases received boost treatment. FET-PET lead to significant (>10%) changes in the initial treatment fields in 11/21 patients and showed additional tumour volume relevant for radiation planning in 6/21 cases, and led to a subsequent decrease of more than 10% of the initial volumes for the boost fields. Conclusion The implementation of FET PET into the planning procedures showed a benefit in terms of accurate definition of skull base lesions as targets for Image-guided stereotactic Radiotherapy. This has to be investigated prospectively in larger cohorts.
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Hess S, Blomberg BA, Rakheja R, Friedman K, Kwee TC, Høilund-Carlsen PF, Alavi A. A brief overview of novel approaches to FDG PET imaging and quantification. Clin Transl Imaging 2014. [DOI: 10.1007/s40336-014-0062-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Hammarlund-Udenaes M. In Vivo Approaches to Assessing the Blood–Brain Barrier. TOPICS IN MEDICINAL CHEMISTRY 2013. [DOI: 10.1007/7355_2013_27] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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