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Carrozzi A, Gramegna LL, Sighinolfi G, Zoli M, Mazzatenta D, Testa C, Lodi R, Tonon C, Manners DN. Methods of diffusion MRI tractography for localization of the anterior optic pathway: A systematic review of validated methods. Neuroimage Clin 2023; 39:103494. [PMID: 37651845 PMCID: PMC10477810 DOI: 10.1016/j.nicl.2023.103494] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 06/21/2023] [Accepted: 08/07/2023] [Indexed: 09/02/2023]
Abstract
The anterior optic pathway (AOP) is a system of three structures (optic nerves, optic chiasma, and optic tracts) that convey visual stimuli from the retina to the lateral geniculate nuclei. A successful reconstruction of the AOP using tractography could be helpful in several clinical scenarios, from presurgical planning and neuronavigation of sellar and parasellar surgery to monitoring the stage of fiber degeneration both in acute (e.g., traumatic optic neuropathy) or chronic conditions that affect AOP structures (e.g., amblyopia, glaucoma, demyelinating disorders or genetic optic nerve atrophies). However, its peculiar anatomy and course, as well as its surroundings, pose a serious challenge to obtaining successful tractographic reconstructions. Several AOP tractography strategies have been adopted but no standard procedure has been agreed upon. We performed a systematic review of the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 2020 guidelines in order to find the combinations of acquisition and reconstruction parameters that have been performed previously and have provided the highest rate of successful reconstruction of the AOP, in order to promote their routine implementation in clinical practice. For this purpose, we reviewed data regarding how the process of anatomical validation of the tractographies was performed. The Cochrane Handbook for Systematic Reviews of Interventions was used to assess the risk of bias and thus the study quality We identified thirty-nine studies that met our inclusion criteria, and only five were considered at low risk of bias and achieved over 80% of successful reconstructions. We found a high degree of heterogeneity in the acquisition and analysis parameters used to perform AOP tractography and different combinations of them can achieve satisfactory levels of anterior optic tractographic reconstruction both in real-life research and clinical scenarios. One thousand s/mm2 was the most frequently used b value, while both deterministic and probabilistic tractography algorithms performed morphological reconstruction of the tract satisfactorily, although probabilistic algorithms estimated a more realistic percentage of crossing fibers (45.6%) in healthy subjects. A wide heterogeneity was also found regarding the method used to assess the anatomical fidelity of the AOP reconstructions. Three main strategies can be found: direct visual direct visual assessment of the tractography superimposed to a conventional MR image, surgical evaluation, and computational methods. Because the latter is less dependent on a priori knowledge of the anatomy by the operator, computational methods of validation of the anatomy should be considered whenever possible.
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Affiliation(s)
- Alessandro Carrozzi
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
| | - Laura Ludovica Gramegna
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy; IRCCS Istituto delle Scienze Neurologiche di Bologna, Functional and Molecular Neuroimaging Unit, Bologna, Italy.
| | - Giovanni Sighinolfi
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
| | - Matteo Zoli
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy; IRCCS Istituto delle Scienze Neurologiche di Bologna, Pituitary Unit, Bologna, Italy
| | - Diego Mazzatenta
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy; IRCCS Istituto delle Scienze Neurologiche di Bologna, Pituitary Unit, Bologna, Italy
| | - Claudia Testa
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Raffaele Lodi
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy; IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Caterina Tonon
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy; IRCCS Istituto delle Scienze Neurologiche di Bologna, Functional and Molecular Neuroimaging Unit, Bologna, Italy
| | - David Neil Manners
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Functional and Molecular Neuroimaging Unit, Bologna, Italy; Department for Life Quality Studies (QUVI), University of Bologna, Bologna, Italy
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Kamali A, Milosavljevic S, Gandhi A, Lano KR, Shobeiri P, Sherbaf FG, Sair HI, Riascos RF, Hasan KM. The Cortico-Limbo-Thalamo-Cortical Circuits: An Update to the Original Papez Circuit of the Human Limbic System. Brain Topogr 2023; 36:371-389. [PMID: 37148369 PMCID: PMC10164017 DOI: 10.1007/s10548-023-00955-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 03/06/2023] [Indexed: 05/08/2023]
Abstract
The Papez circuit, first proposed by James Papez in 1937, is a circuit believed to control memory and emotions, composed of the cingulate cortex, entorhinal cortex, parahippocampal gyrus, hippocampus, hypothalamus, and thalamus. Pursuant to James Papez, Paul Yakovlev and Paul MacLean incorporated the prefrontal/orbitofrontal cortex, septum, amygdalae, and anterior temporal lobes into the limbic system. Over the past few years, diffusion-weighted tractography techniques revealed additional limbic fiber connectivity, which incorporates multiple circuits to the already known complex limbic network. In the current review, we aimed to comprehensively summarize the anatomy of the limbic system and elaborate on the anatomical connectivity of the limbic circuits based on the published literature as an update to the original Papez circuit.
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Affiliation(s)
- Arash Kamali
- Department of Diagnostic and Interventional Radiology, Neuroradiology Section, University of Texas at Houston, 6431 Fannin St, Houston, TX, 77030, USA.
| | | | - Anusha Gandhi
- Baylor College of Medicine Medical School, Houston, TX, USA
| | - Kinsey R Lano
- McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Parnian Shobeiri
- Faculty of Medicine, Tehran University Medical School, Tehran, Iran
| | - Farzaneh Ghazi Sherbaf
- Department of Radiology and Radiological Science, Division of Neuroradiology, The Russell H. Morgan, Johns Hopkins University, Baltimore, MD, USA
| | - Haris I Sair
- Department of Radiology and Radiological Science, Division of Neuroradiology, The Russell H. Morgan, Johns Hopkins University, Baltimore, MD, USA
| | - Roy F Riascos
- Department of Diagnostic and Interventional Radiology, Neuroradiology Section, University of Texas at Houston, 6431 Fannin St, Houston, TX, 77030, USA
| | - Khader M Hasan
- Department of Diagnostic and Interventional Radiology, Neuroradiology Section, University of Texas at Houston, 6431 Fannin St, Houston, TX, 77030, USA
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Voxel-Mirrored Homotopic Connectivity Is Altered in Meibomian Gland Dysfunction Patients That Are Morbidly Obese. Brain Sci 2022; 12:brainsci12081078. [PMID: 36009141 PMCID: PMC9405716 DOI: 10.3390/brainsci12081078] [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: 04/07/2022] [Revised: 06/14/2022] [Accepted: 07/21/2022] [Indexed: 11/24/2022] Open
Abstract
Purpose: To investigate the altered functional connectivity (FC) of the cerebral hemispheres in patients with morbid obesity (MO) with meibomian gland dysfunction (MGD) by voxel-mirrored homotopic connectivity (VMHC). Methods: Patients and matched healthy controls (HCs) were recruited, and all subjects underwent functional resonance magnetic imaging (fMRI), and VMHC results were processed statistically to assess the differences in FC in different brain regions between the two groups. We further used ROC curves to evaluate the diagnostic value of these differences. We also used Pearson’s correlation analysis to explore the relationship between changes in VMHC values in specific brain regions, visual acuity, and Mini-Mental State Examination (MMSE) score. Conclusions: Patients with morbid obesity and MGD had abnormal FC in the cerebral hemispheres in several specific brain areas, which were mainly concentrated in pathways related to vision and perception and may correlate to some extent with the clinical presentations of the patients.
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Michele R, Ivana S, Maria DV, Luca B, Domenico L, Maria ZF, Alessandro DB, Silvio S, Khalid AO, Valeria M, Pietro A. Tracing in vivo the dorsal loop of the optic radiation: convergent perspectives from tractography and electrophysiology compared to a neuroanatomical ground truth. Brain Struct Funct 2022; 227:1357-1370. [PMID: 35320828 DOI: 10.1007/s00429-021-02430-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 11/12/2021] [Indexed: 01/18/2023]
Abstract
The temporo-parietal junction (TPJ) is a cortical area contributing to a multiplicity of visual, language-related, and cognitive functions. In line with this functional richness, also the organization of the underlying white matter is highly complex and includes several bundles. The few studies tackling the outcome and neurological burdens of surgical operations addressing TPJ document the presence of language disturbances and visual field damages, with the latter hardly recovered in time. This observation advocates for identifying and functionally monitoring the optic radiation (OR) bundles that cross the white matter below the TPJ. In the present study, we adopted a multimodal approach to address the anatomo-functional correlates of the OR's dorsal loop. In particular, we combined cadavers' dissection with tractographic and electrophysiological data collected in drug-resistant epileptic patients explored by stereoelectroencephalography (SEEG). Cadaver dissection allowed us to appreciate the course and topography of the dorsal loop. More surprisingly, both tractographic and electrophysiological observations converged on a unitary picture highly coherent with the data obtained by neuroanatomical observation. The combination of diverse and multimodal observations allows overcoming the limitations intrinsic to single methodologies, defining a unitary picture which makes it possible to investigate the dorsal loop both presurgically and at the individual patient level, ultimately contributing to limit the postsurgical damages. Notwithstanding, such a combined approach could serve as a model of investigation for future neuroanatomical inquiries tackling white matter fibers anatomy and function through SEEG-derived neurophysiological data.
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Affiliation(s)
- Rizzi Michele
- "C.Munari" Epilepsy Surgery Centre, ASST GOM Niguarda, Piazza Dell'Ospedale Maggiore, 20162, Milan, Italy
| | - Sartori Ivana
- "C.Munari" Epilepsy Surgery Centre, ASST GOM Niguarda, Piazza Dell'Ospedale Maggiore, 20162, Milan, Italy.
| | - Del Vecchio Maria
- Institute of Neuroscience, National Research Council of Italy, Parma, Italy
| | - Berta Luca
- Department of Medical Physics, ASST GOM Niguarda, Milan, Italy
| | - Lizio Domenico
- Department of Medical Physics, ASST GOM Niguarda, Milan, Italy
| | - Zauli Flavia Maria
- "C.Munari" Epilepsy Surgery Centre, ASST GOM Niguarda, Piazza Dell'Ospedale Maggiore, 20162, Milan, Italy
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, Italy
| | - De Benedictis Alessandro
- Department of Neurosciences, Neurosurgery Unit, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Sarubbo Silvio
- Department of Neurosurgery, Ospedale Santa Chiara, Trento, Italy
| | - Al-Orabi Khalid
- "C.Munari" Epilepsy Surgery Centre, ASST GOM Niguarda, Piazza Dell'Ospedale Maggiore, 20162, Milan, Italy
| | - Mariani Valeria
- Neurology and Stroke Unit, ASST Sette Laghi-Ospedale di Circolo, Varese, Italy
| | - Avanzini Pietro
- Institute of Neuroscience, National Research Council of Italy, Parma, Italy
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Morales H. Current and Future Challenges of Functional MRI and Diffusion Tractography in the Surgical Setting: From Eloquent Brain Mapping to Neural Plasticity. Semin Ultrasound CT MR 2021; 42:474-489. [PMID: 34537116 DOI: 10.1053/j.sult.2021.07.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Decades ago, Spetzler (1986) and Sawaya (1998) provided a rough brain segmentation of the eloquent areas of the brain, aimed to help surgical decisions in cases of vascular malformations and tumors, respectively. Currently in clinical use, their criteria are in need of revision. Defining functions (eg, sensorimotor, language and visual) that should be preserved during surgery seems a straightforward task. In practice, locating the specific areas that could cause a permanent vs transient deficit is not an easy task. This is particularly true for the associative cortex and cognitive domains such as language. The old model, with Broca's and Wernicke's areas at the forefront, has been superseded by a dual-stream model of parallel language processing; named ventral and dorsal pathways. This complicated network of cortical hubs and subcortical white matter pathways needing preservation during surgery is a work in progress. Preserving not only cortical regions but most importantly preserving the connections, or white matter fiber bundles, of core regions in the brain is the new paradigm. For instance, the arcuate fascicululs and inferior fronto-occipital fasciculus are key components of the dorsal and ventral language pathways, respectively; and their damage result in permanent language deficits. Interestedly, the damage of the temporal portions of these bundles -where there is a crossroad with other multiple bundles-, appears to be more important (permanent) than the damage of the frontal portions - where plasticity and contralateral activation could help. Although intraoperative direct cortical and subcortical stimulation have contributed largely, advanced MR techniques such as functional MRI (fMRI) and diffusion tractography (DT), are at the epi-center of our current understanding. Nevertheless, these techniques posse important challenges: such as neurovascular uncoupling or venous bias on fMRI; and appropriate anatomical validation or accurate representation of crossing fibers on DT. These limitations should be well understood and taken into account in clinical practice. Unifying multidisciplinary research and clinical efforts is desirable, so these techniques could contribute more efficiently not only to locate eloquent areas but to improve outcomes and our understanding of neural plasticity. Finally, although there are constant anatomical and functional regions at the individual level, there is a known variability at the inter-individual level. This concept should strengthen the importance of a personalized approach when evaluating these regions on fMRI and DT. It should strengthen the importance of personalized treatments as well, aimed to meet tailored needs and expectations.
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Affiliation(s)
- Humberto Morales
- Section of Neuroradiology, University of Cincinnati Medical Center, Cincinnati, OH.
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Bethard JD, Ainger TJ, Gonciar A, Nyárádi Z. Surviving (but not thriving) after cranial vault trauma: A case study from Transylvania. INTERNATIONAL JOURNAL OF PALEOPATHOLOGY 2021; 34:122-129. [PMID: 34243131 DOI: 10.1016/j.ijpp.2021.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 05/27/2021] [Accepted: 06/20/2021] [Indexed: 06/13/2023]
Abstract
OBJECTIVE To link an antemortem cranial injury on the left parietal bone with potential neurocognitive consequences. MATERIALS The skeleton of a male individual from a Székely archaeological site in Transylvania was examined. The skeleton was radiocarbon dated to Cal AD 1450 and AD 1640 and presented a well-healed antemortem penetrating cranial injury on the left parietal bone. METHODS Macroscopic and radiographic analyses were conducted and the cranium was also archived digitally with a Faro FreeStyle3D scanner. In addition, well-known literature from neuroscience was synthesized in order to better understand the likely neurological consequences of the injury. RESULTS The literature suggests that tasks of attention and working memory, sensory processing, language processing, and vision are affected when the parietal lobe of the brain is injured. CONCLUSIONS Burial 195 did not likely return to a 'normal' life after he survived the cranial injury. SIGNIFICANCE This study demonstrates that bioarcheological interpretations involving antemortem cranial injuries can be enhanced by collaboration with neuroscientists. Bioarcheological interpretations are improved when the consequences of soft tissue injuries are understood. LIMITATIONS This study was limited by a lack of historical documents relevant to the region, time period, and specific case study. In addition, interpretations are cautionary because brain functioning cannot be assessed in vivo in the absence of life. SUGGESTIONS FOR FURTHER RESEARCH Bioarcheologists who study antemortem cranial injuries should continue to collaborate with neuroscientists.
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Affiliation(s)
- Jonathan D Bethard
- University of South Florida, Department of Anthropology, 4202 East Fowler Avenue, SOC107, Tampa, FL 33620, USA.
| | - Timothy J Ainger
- University of Kentucky College of Medicine, Department of Neurology, 740 S. Limestone, Kentucky Clinic J-414, Lexington, KY 40536, USA
| | | | - Zsolt Nyárádi
- Haáz Rezső Múzeum, Strada Beclean 2-6, Odorheiu Secuiesc 535600, Romania
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Takemura H, Palomero-Gallagher N, Axer M, Gräßel D, Jorgensen MJ, Woods R, Zilles K. Anatomy of nerve fiber bundles at micrometer-resolution in the vervet monkey visual system. eLife 2020; 9:e55444. [PMID: 32844747 PMCID: PMC7532002 DOI: 10.7554/elife.55444] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 08/22/2020] [Indexed: 12/11/2022] Open
Abstract
Although the primate visual system has been extensively studied, detailed spatial organization of white matter fiber tracts carrying visual information between areas has not been fully established. This is mainly due to the large gap between tracer studies and diffusion-weighted MRI studies, which focus on specific axonal connections and macroscale organization of fiber tracts, respectively. Here we used 3D polarization light imaging (3D-PLI), which enables direct visualization of fiber tracts at micrometer resolution, to identify and visualize fiber tracts of the visual system, such as stratum sagittale, inferior longitudinal fascicle, vertical occipital fascicle, tapetum and dorsal occipital bundle in vervet monkey brains. Moreover, 3D-PLI data provide detailed information on cortical projections of these tracts, distinction between neighboring tracts, and novel short-range pathways. This work provides essential information for interpretation of functional and diffusion-weighted MRI data, as well as revision of wiring diagrams based upon observations in the vervet visual system.
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Affiliation(s)
- Hiromasa Takemura
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, and Osaka UniversityOsakaJapan
- Graduate School of Frontier Biosciences, Osaka UniversityOsakaJapan
| | - Nicola Palomero-Gallagher
- Institute of Neuroscience and Medicine INM-1, Research Centre JülichJülichGermany
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH AachenAachenGermany
- C. & O. Vogt Institute for Brain Research, Heinrich-Heine-UniversityDüsseldorfGermany
| | - Markus Axer
- Institute of Neuroscience and Medicine INM-1, Research Centre JülichJülichGermany
| | - David Gräßel
- Institute of Neuroscience and Medicine INM-1, Research Centre JülichJülichGermany
| | - Matthew J Jorgensen
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of MedicineWinston-SalemUnited States
| | - Roger Woods
- Ahmanson-Lovelace Brain Mapping Center, Departments of Neurology and of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, UCLALos AngelesUnited States
| | - Karl Zilles
- Institute of Neuroscience and Medicine INM-1, Research Centre JülichJülichGermany
- JARA - Translational Brain MedicineAachenGermany
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Jacqmot O, Van Thielen B, Michotte A, de Mey J, Provyn S, Tresignie J. Neuroanatomical Reconstruction of the Canine Visual Pathway Using Diffusion Tensor Imaging. Front Neuroanat 2020; 14:54. [PMID: 32973464 PMCID: PMC7461977 DOI: 10.3389/fnana.2020.00054] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/28/2020] [Indexed: 11/13/2022] Open
Abstract
The first anatomical atlas of diffusion tensor imaging (DTI) of white matter pathways in the canine brain was published in 2013; however, the anatomical orientation of the entire visual pathway in the canine brain, from the retina to the cortex, has not yet been studied using DTI. In the present study, 3T DTI magnetic resonance (MR) images of three dogs euthanized for reasons other than neurological disorders were obtained. The process of obtaining combined fractional anisotropy and directional maps was initiated within 1 h of death. The heads were amputated immediately after MR imaging and stored in 10% formalin until dissection and histological sampling was performed. The trajectory of the visual pathway is dissimilar to the horizontal representation in other literature. To our knowledge, ours is the first study to visualize the entire canine visual pathway in its full antero-posterior extension. Fibers from the retina to the cortex passed through the optic nerve, optic chiasm, optic tracts, lateral geniculate nucleus, Meyer’s and Baum’s loops, and pretectal fibers. Their projections to the cortex were similar to those in the human visual pathway. The crossing of fibers at the optic chiasm occurred in 75% of fibers. In addition to advancing our knowledge in this field of study, these results could help plan neurosurgical and radiotherapeutic procedures to avoid unnecessary damage to the visual fiber system.
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Affiliation(s)
- Olivier Jacqmot
- Anatomical Research and Clinical Studies (ARCS), Vrije Universiteit Brussel, Brussels, Belgium.,MOVE-HIM (Morpho Veterinary and Human Imaging) Brussels, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | - Bert Van Thielen
- MOVE-HIM (Morpho Veterinary and Human Imaging) Brussels, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium.,Department of Radiology, UZ Brussel, Brussels, Belgium.,Odisee Brussel, Educational Department for Imaging Technologists, Brussels, Belgium.,Anatomical Research, Training and Education (ARTE), Vrije Universiteit Brussel, Brussels, Belgium
| | - Alex Michotte
- Department of Neurology and Neuropathology, Neuroanatomy, UZ Brussel, Brussels, Belgium
| | - Johan de Mey
- Department of Radiology, UZ Brussel, Brussels, Belgium
| | - Steven Provyn
- Anatomical Research and Clinical Studies (ARCS), Vrije Universiteit Brussel, Brussels, Belgium
| | - Jonathan Tresignie
- Anatomical Research and Clinical Studies (ARCS), Vrije Universiteit Brussel, Brussels, Belgium
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Kamali A, Karbasian N, Ghazi Sherbaf F, Wilken LA, Aein A, Sair HI, Arevalo Espejo O, Rabiei P, Choi SJ, Mirbagheri S, Riascos RF, Hasan KM. Uncovering the Dorsal Thalamo-hypothalamic Tract of the Human Limbic System. Neuroscience 2020; 432:55-62. [DOI: 10.1016/j.neuroscience.2020.02.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 02/14/2020] [Accepted: 02/17/2020] [Indexed: 10/24/2022]
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10
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Wang FY, Wang P, Yang CX, Zhou T, Jiang JL, Meng XH. Correlation between the Position of the Pituitary Stalk as Determined by Diffusion Tensor Imaging and Its Location as Determined at the Time of Surgical Resection of Pituitary Adenomas. J Korean Neurosurg Soc 2020; 63:504-512. [PMID: 32182411 PMCID: PMC7365283 DOI: 10.3340/jkns.2019.0205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 12/18/2019] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE An important factor during pituitary adenoma surgery is to preserve pituitary stalk (PS) as this plays a role in reduction of the risk of postoperative diabetes insipidus. The hypothalamic-hypophyseal tract (HHT) projects through the PS to the posterior pituitary gland. To reconstruct white matter fiber pathways, methods like diffusion tensor imaging (DTI) tractography have been widely used. In this report we attempted to predict the position of PS using DTI tractography and to assess its intraoperative correlation during surgery of pituitary adenomas. METHODS DTI tractography was used to tract the HHT in nine patients before craniotomy for pituitary adenomas. The DTI location of the HHT was compared with the PS position identified at the time of surgery. DTI fiber tracking was carried out in nine patients prior to the planned craniotomy for pituitary adenomas. In one patient, the PS could not be identified during the surgery. In the other eight patients, a comparison was made between the location of the HHT identified by DTI and the position of the PS visualized at the time of surgery. RESULTS The position of the HHT identified by DTI showed consistency with the intraoperative position of the PS in seven patients (88.9% concordance). CONCLUSION This study shows that DTI can identify the position of the HHT and thus the position of the PS with a high degree of reliability.
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Affiliation(s)
- Fu-Yu Wang
- Department of Neurosurgery, The First Medical Center, PLA General Hospital, Beijing, China
| | - Peng Wang
- Department of Neurosurgery, The First Medical Center, PLA General Hospital, Beijing, China
| | - Chen-Xuan Yang
- Department of Neurosurgery, The First Medical Center, PLA General Hospital, Beijing, China
| | - Tao Zhou
- Department of Neurosurgery, The First Medical Center, PLA General Hospital, Beijing, China
| | - Jin-Li Jiang
- Department of Neurosurgery, The First Medical Center, PLA General Hospital, Beijing, China
| | - Xiang-Hui Meng
- Department of Neurosurgery, The First Medical Center, PLA General Hospital, Beijing, China
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Herbet G, Duffau H. Revisiting the Functional Anatomy of the Human Brain: Toward a Meta-Networking Theory of Cerebral Functions. Physiol Rev 2020; 100:1181-1228. [PMID: 32078778 DOI: 10.1152/physrev.00033.2019] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
For more than one century, brain processing was mainly thought in a localizationist framework, in which one given function was underpinned by a discrete, isolated cortical area, and with a similar cerebral organization across individuals. However, advances in brain mapping techniques in humans have provided new insights into the organizational principles of anatomo-functional architecture. Here, we review recent findings gained from neuroimaging, electrophysiological, as well as lesion studies. Based on these recent data on brain connectome, we challenge the traditional, outdated localizationist view and propose an alternative meta-networking theory. This model holds that complex cognitions and behaviors arise from the spatiotemporal integration of distributed but relatively specialized networks underlying conation and cognition (e.g., language, spatial cognition). Dynamic interactions between such circuits result in a perpetual succession of new equilibrium states, opening the door to considerable interindividual behavioral variability and to neuroplastic phenomena. Indeed, a meta-networking organization underlies the uniquely human propensity to learn complex abilities, and also explains how postlesional reshaping can lead to some degrees of functional compensation in brain-damaged patients. We discuss the major implications of this approach in fundamental neurosciences as well as for clinical developments, especially in neurology, psychiatry, neurorehabilitation, and restorative neurosurgery.
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Affiliation(s)
- Guillaume Herbet
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France; Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors," INSERM U1191, Institute of Functional Genomics, Montpellier, France; and University of Montpellier, Montpellier, France
| | - Hugues Duffau
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France; Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors," INSERM U1191, Institute of Functional Genomics, Montpellier, France; and University of Montpellier, Montpellier, France
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Guo X, Yao S, Xing B. Letter to the Editor. Is 7-Tesla MRI necessary in the assessment of microstructural injury to visual pathways due to pituitary adenomas? J Neurosurg 2020; 132:675-677. [PMID: 31100727 DOI: 10.3171/2019.2.jns19413] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Xiaopeng Guo
- 1Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- 2China Pituitary Disease Registry Center, Chinese Pituitary Adenoma Cooperative Group, Beijing, China
| | - Shun Yao
- 3The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Bing Xing
- 4Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, and
- 5China Pituitary Disease Registry Center, Chinese Pituitary Adenoma Cooperative Group, Beijing, China
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13
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Visual loss and recovery in chiasmal compression. Prog Retin Eye Res 2019; 73:100765. [DOI: 10.1016/j.preteyeres.2019.06.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 06/05/2019] [Accepted: 06/12/2019] [Indexed: 12/18/2022]
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14
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Hofstetter S, Sabbah N, Mohand-Saïd S, Sahel JA, Habas C, Safran AB, Amedi A. The development of white matter structural changes during the process of deterioration of the visual field. Sci Rep 2019; 9:2085. [PMID: 30765782 PMCID: PMC6375971 DOI: 10.1038/s41598-018-38430-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 12/27/2018] [Indexed: 12/02/2022] Open
Abstract
Emerging evidence suggests that white matter plasticity in the adult brain is preserved after sensory and behavioral modifications. However, little is known about the progression of structural changes during the process of decline in visual input. Here we studied two groups of patients suffering from advanced retinitis pigmentosa with specific deterioration of the visual field: patients who had lost their peripheral visual field, retaining only central (“tunnel”) vision, and blind patients with complete visual field loss. Testing of these homogeneous groups made it possible to assess the extent to which the white matter is affected by loss of partial visual input and whether partially preserved visual input suffices to sustain stability in tracts beyond the primary visual system. Our results showed gradual changes in diffusivity that are indicative of degenerative processes in the primary visual pathway comprising the optic tract and the optic radiation. Interestingly, changes were also found in tracts of the ventral stream and the corticospinal fasciculus, depicting a gradual reorganisation of these tracts consequentially to the gradual loss of visual field coverage (from intact perception to partial vision to complete blindness). This reorganisation may point to microstructural plasticity underlying adaptive behavior and cross-modal integration after partial visual deprivation.
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Affiliation(s)
- Shir Hofstetter
- Department of Medical Neurobiology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel. .,The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel.
| | - Norman Sabbah
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - Saddek Mohand-Saïd
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012, Paris, France
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012, Paris, France.,Fondation Ophtalmologique A. de Rothschild, F-75019, Paris, France.,Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Christophe Habas
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012, Paris, France.,Centre de Neuro-Imagerie, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, F-75012, France
| | - Avinoam B Safran
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012, Paris, France.,Department of Clinical Neurosciences, Geneva University School of Medicine, Geneva, Switzerland
| | - Amir Amedi
- Department of Medical Neurobiology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel. .,The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel. .,Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France. .,The Cognitive Science Program, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel.
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15
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Wang P, Wang D, Zhang J, Bai R, Qian M, Sun Y, Lu Y, Zhang X. Evaluation of Submillimeter Diffusion Imaging of the Macaque Brain Using Readout-Segmented EPI at 7 T. IEEE Trans Biomed Eng 2019; 66:2945-2951. [PMID: 30762524 DOI: 10.1109/tbme.2019.2899132] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The purpose of the present study was to achieve submillimeter-level diffusion tensor imaging (DTI) of the macaque brain by using diffusion weighted (DW) readout-segmented echo planar imaging (rsEPI) with an optimized protocol at 7 T MRI. METHODS Three anesthetized macaques were included in this study. Under different scan settings, we compared the signal-to-noise ratio (SNR) and geometric distortion of DW images, implemented an optimized protocol for submillimeter-level DTI acquisition, and evaluated its performance. RESULTS The parallel-imaging-enabled (in GRAPPA mode) monopolar or monopolar+ diffusion scheme has higher SNR versus bipolar scheme, whereas trivial differences in SNR and image geometric distortion occurred when using increased readout segments with monopolar and monopolar+ that did not reach statistical significance. Submillimeter-level (0.8 mm isotropic) DTI data provide a sharper delineation of white matter contour than the 1 mm level. CONCLUSION The rsEPI technique with parallel imaging enabled, and with the shortest readout segments in conjunction with monopolar/monopolar+ diffusion encoding scheme, may be optimal for submillimeter-level diffusion imaging over macaque brains in vivo. SIGNIFICANCE rsEPI could effectively merit high-resolution DTI for in vivo macaque brain submillimeter structural architecture investigations at ultrahigh fields.
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16
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Herbet G, Zemmoura I, Duffau H. Functional Anatomy of the Inferior Longitudinal Fasciculus: From Historical Reports to Current Hypotheses. Front Neuroanat 2018; 12:77. [PMID: 30283306 PMCID: PMC6156142 DOI: 10.3389/fnana.2018.00077] [Citation(s) in RCA: 192] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 08/30/2018] [Indexed: 12/13/2022] Open
Abstract
The inferior longitudinal fasciculus (ILF) is a long-range, associative white matter pathway that connects the occipital and temporal-occipital areas of the brain to the anterior temporal areas. In view of the ILF's anatomic connections, it has been suggested that this pathway has a major role in a relatively large array of brain functions. Until recently, however, the literature data on these potential functions were scarce. Here, we review the key findings of recent anatomic, neuromodulation, and neuropsychological studies. We also summarize reports on how this tract is disrupted in a wide range of brain disorders, including psychopathologic, neurodevelopmental, and neurologic diseases. Our review reveals that the ILF is a multilayered, bidirectional tract involved in processing and modulating visual cues and thus in visually guided decisions and behaviors. Accordingly, sudden disruption of the ILF by neurologic insult is mainly associated with neuropsychological impairments of visual cognition (e.g., visual agnosia, prosopagnosia, and alexia). Furthermore, disruption of the ILF may constitute the pathophysiologic basis for visual hallucinations and socio-emotional impairments in schizophrenia, as well as emotional difficulties in autism spectrum disorder. Degeneration of the ILF in neurodegenerative diseases affecting the temporal lobe may explain (at least in part) the gradual onset of semantic and lexical access difficulties. Although some of the functions mediated by the ILF appear to be relatively lateralized, observations from neurosurgery suggest that disruption of the tract's anterior portion can be dynamically compensated for by the contralateral portion. This might explain why bilateral disruption of the ILF in either acute or progressive disease is highly detrimental in neuropsychological terms.
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Affiliation(s)
- Guillaume Herbet
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
- INSERM-1051, Team 4, Saint-Eloi Hospital, Institute for Neurosciences of Montpellier, Montpellier, France
- University of Montpellier, Montpellier, France
| | - Ilyess Zemmoura
- Department of Neurosurgery, Tours University Medical Center, Tours, France
- UMR 1253, iBrain, INSERM, University of Tours, Tours, France
| | - Hugues Duffau
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
- INSERM-1051, Team 4, Saint-Eloi Hospital, Institute for Neurosciences of Montpellier, Montpellier, France
- University of Montpellier, Montpellier, France
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17
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Mutlu U, Ikram MK, Roshchupkin GV, Bonnemaijer PWM, Colijn JM, Vingerling JR, Niessen WJ, Ikram MA, Klaver CCW, Vernooij MW. Thinner retinal layers are associated with changes in the visual pathway: A population-based study. Hum Brain Mapp 2018; 39:4290-4301. [PMID: 29935103 DOI: 10.1002/hbm.24246] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 05/26/2018] [Accepted: 05/29/2018] [Indexed: 01/23/2023] Open
Abstract
Increasing evidence shows that thinner retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL), assessed on optical coherence tomography (OCT), are reflecting global brain atrophy. Yet, little is known on the relation of these layers with specific brain regions. Using voxel-based analysis, we aimed to unravel specific brain regions associated with these retinal layers. We included 2,235 persons (mean age: 67.3 years, 55% women) from the Rotterdam Study (2007-2012) who had gradable retinal OCT images and brain magnetic resonance imaging (MRI) scans, including diffusion tensor (DT) imaging. Thicknesses of peripapillary RNFL and perimacular GCL were measured using an automated segmentation algorithm. Voxel-based morphometry protocols were applied to process DT-MRI data. We investigated the association between retinal layer thickness with voxel-wise gray matter density and white matter microstructure by performing linear regression models. We found that thinner RNFL and GCL were associated with lower gray matter density in the visual cortex, and with lower fractional anisotropy and higher mean diffusivity in white matter tracts that are part of the optic radiation. Furthermore, thinner GCL was associated with lower gray matter density of the thalamus. Thinner RNFL and GCL are associated with gray and white matter changes in the visual pathway suggesting that retinal thinning on OCT may be specifically associated with changes in the visual pathway rather than with changes in the global brain. These findings may serve as a basis for understanding visual symptoms in elderly patients, patients with Alzheimer's disease, or patients with posterior cortical atrophy.
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Affiliation(s)
- Unal Mutlu
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Ophthalmology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Mohammad K Ikram
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Neurology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Gennady V Roshchupkin
- Department of Radiology and Nuclear Medicine, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Medical Informatics, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Pieter W M Bonnemaijer
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Ophthalmology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Johanna M Colijn
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Ophthalmology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Johannes R Vingerling
- Department of Ophthalmology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Wiro J Niessen
- Department of Radiology and Nuclear Medicine, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Medical Informatics, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, the Netherlands
| | - Mohammad A Ikram
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Neurology, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Radiology and Nuclear Medicine, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Caroline C W Klaver
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Ophthalmology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Meike W Vernooij
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, the Netherlands.,Department of Radiology and Nuclear Medicine, Erasmus University Medical Center, Rotterdam, the Netherlands
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18
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Kuchling J, Backner Y, Oertel FC, Raz N, Bellmann-Strobl J, Ruprecht K, Paul F, Levin N, Brandt AU, Scheel M. Comparison of probabilistic tractography and tract-based spatial statistics for assessing optic radiation damage in patients with autoimmune inflammatory disorders of the central nervous system. NEUROIMAGE-CLINICAL 2018; 19:538-550. [PMID: 29984162 PMCID: PMC6029567 DOI: 10.1016/j.nicl.2018.05.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 05/03/2018] [Accepted: 05/06/2018] [Indexed: 10/28/2022]
Abstract
Background Diffusion Tensor Imaging (DTI) can evaluate microstructural tissue damage in the optic radiation (OR) of patients with clinically isolated syndrome (CIS), early relapsing-remitting multiple sclerosis and neuromyelitis optica spectrum disorders (NMOSD). Different post-processing techniques, e.g. tract-based spatial statistics (TBSS) and probabilistic tractography, exist to quantify this damage. Objective To evaluate the capacity of TBSS-based atlas region-of-interest (ROI) combination with 1) posterior thalamic radiation ROIs from the Johns Hopkins University atlas (JHU-TBSS), 2) Juelich Probabilistic ROIs (JUEL-TBSS) and tractography methods using 3) ConTrack (CON-PROB) and 4) constrained spherical deconvolution tractography (CSD-PROB) to detect OR damage in patients with a) NMOSD with prior ON (NMOSD-ON), b) CIS and early RRMS patients with ON (CIS/RRMS-ON) and c) CIS and early RRMS patients without prior ON (CIS/RRMS-NON) against healthy controls (HCs). Methods Twenty-three NMOSD-ON, 18 CIS/RRMS-ON, 21 CIS/RRMS-NON, and 26 HCs underwent 3 T MRI. DTI data analysis was carried out using JUEL-TBSS, JHU-TBSS, CON-PROB and CSD-PROB. Optical coherence tomography (OCT) and visual acuity testing was performed in the majority of patients and HCs. Results Absolute OR fractional anisotropy (FA) values differed between all methods but showed good correlation and agreement in Bland-Altman analysis. OR FA values between NMOSD and HC differed throughout the methodologies (p-values ranging from p < 0.0001 to 0.0043). ROC-analysis and effect size estimation revealed higher AUCs and R2 for CSD-PROB (AUC = 0.812; R2 = 0.282) and JHU-TBSS (AUC = 0.756; R2 = 0.262), compared to CON-PROB (AUC = 0.742; R2 = 0.179) and JUEL-TBSS (AUC = 0.719; R2 = 0.161). Differences between CIS/RRMS-NON and HC were only observable in CSD-PROB (AUC = 0.796; R2 = 0.094). No significant differences between CIS/RRMS-ON and HC were detected by any of the methods. Conclusions All DTI post-processing techniques facilitated the detection of OR damage in patient groups with severe microstructural OR degradation. The comparison of distinct disease groups by use of different methods may lead to different - either false-positive or false-negative - results. Since different DTI post-processing approaches seem to provide complementary information on OR damage, application of distinct methods may depend on the relevant research question.
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Key Words
- AD, axial diffusivity
- AUC, area under the curve
- CIS, clinically isolated syndrome
- CON, Contrack
- CSD, constrained spherical deconvolution
- DTI
- DTI, diffusion tensor imaging
- DW-MRI, diffusion weighted magnetic resonance imaging
- DWI, diffusion weighted imaging
- FA, fractional anisotropy
- FOD, fiber orientation distribution
- HC, Healthy Control
- JHU, Johns Hopkins University DTI white matter atlas
- JUEL, Juelich histological atlas
- LGN, lateral geniculate nucleus
- MD, mean diffusivity
- MS, multiple sclerosis
- Multiple sclerosis
- NMOSD, neuromyelitis optica spectrum disorder
- Neuromyelitis optica
- OCT, optical coherence tomography
- ON, optic neuritis
- OR, optic radiation
- Optic radiation
- PROB, probabilistic tractography
- Probabilistic tractography
- RD, radial diffusivity
- RNFL, retinal nerve fiber layer thickness
- ROC, receiver operating characteristic
- ROI, region of interest
- RRMS, relapsing-remitting multiple sclerosis
- SD, standard deviation
- SEM, standard error of the mean
- TBSS
- TBSS, tract-based spatial statistics
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Affiliation(s)
- Joseph Kuchling
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neurocure Cluster of Excellence, NeuroCure Clinical Research Center, NCRC Charité, Charitéplatz 1, 10117 Berlin, Germany; Department of Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
| | - Yael Backner
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah-Hebrew-University Medical Center, Kiryat Hadassah Ein kerem, Jerusalem 91120, Israel.
| | - Frederike C Oertel
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neurocure Cluster of Excellence, NeuroCure Clinical Research Center, NCRC Charité, Charitéplatz 1, 10117 Berlin, Germany.
| | - Noa Raz
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah-Hebrew-University Medical Center, Kiryat Hadassah Ein kerem, Jerusalem 91120, Israel.
| | - Judith Bellmann-Strobl
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neurocure Cluster of Excellence, NeuroCure Clinical Research Center, NCRC Charité, Charitéplatz 1, 10117 Berlin, Germany; Experimental and Clinical Research Center, Max Delbrueck Center for Molecular Medicine and Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
| | - Klemens Ruprecht
- Department of Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
| | - Friedemann Paul
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neurocure Cluster of Excellence, NeuroCure Clinical Research Center, NCRC Charité, Charitéplatz 1, 10117 Berlin, Germany; Department of Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; Experimental and Clinical Research Center, Max Delbrueck Center for Molecular Medicine and Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
| | - Netta Levin
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah-Hebrew-University Medical Center, Kiryat Hadassah Ein kerem, Jerusalem 91120, Israel.
| | - Alexander U Brandt
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neurocure Cluster of Excellence, NeuroCure Clinical Research Center, NCRC Charité, Charitéplatz 1, 10117 Berlin, Germany; Department of Neurology, University of California, 1001 Health Sciences Road, Irvine Hall, Irvine, CA 92697, USA.
| | - Michael Scheel
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neurocure Cluster of Excellence, NeuroCure Clinical Research Center, NCRC Charité, Charitéplatz 1, 10117 Berlin, Germany.
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19
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Wang F, Zhang J, Wang P, Zhou T, Meng X, Jiang J. Prediction of pituitary stalk position in pituitary adenomas by visualization of the hypothalamo-hypophyseal tract using diffusion tensor imaging tractography. Medicine (Baltimore) 2018; 97:e0052. [PMID: 29517662 PMCID: PMC5882425 DOI: 10.1097/md.0000000000010052] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The preservation of pituitary stalk during surgery is very important for neurosurgeons. Sometimes, it is hard to identify the pituitary stalk in the operation. The hypothalamo-hypophyseal tract (HHT) projects through the pituitary stalk to the posterior pituitary gland. If the HHT can be identified, the position of pituitary stalk will be visualized. The diffusion tensor imaging (DTI) fiber tracking technique has been widely used for the quantitative assessment of the white matter integrity and thus may be suitable for the evaluation of the HHT.DTI was used to track the HHT in 11 patients with pituitary adenoma, and the location of the tract was compared with the pituitary stalk of postoperative image in those patients.The fiber tracking and 3D visualization of the HHT were successfully carried out in all 11 patients. Comparison between the tract and pituitary stalk of postoperative magnetic resonance imaging (MRI) was carried out in 9 patients. The results revealed that the position of tract was consistent with the pituitary stalk of postoperative MRI image in 8 patients (88.9%). The properties of tract showed that the median number of tract was 5.18 ± 7.00, the median fractional anisotropy (FA) was 0.14 ± 0.04, and the median length was 28.81 ± 7.94 mm.HHT can be tracked and visualized with the DTI-FT technique. It will be helpful to identify the location of pituitary stalk preoperatively.
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20
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Hasan KM, Mwangi B, Keser Z, Riascos R, Sargsyan AE, Kramer LA. Brain Quantitative MRI Metrics in Astronauts as a Unique Professional Group. J Neuroimaging 2018; 28:256-268. [DOI: 10.1111/jon.12501] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 01/04/2018] [Accepted: 01/16/2018] [Indexed: 11/28/2022] Open
Affiliation(s)
- Khader M. Hasan
- Medical SchoolDepartment of Diagnostic and Interventional ImagingThe University of Texas Health Science Center Houston TX
| | - Benson Mwangi
- Medical SchoolDepartment of PsychiatryThe University of Texas Health Science Center Houston TX
| | - Zafer Keser
- Medical SchoolDepartment of NeurologyThe University of Texas Health Science Center Houston TX
| | - Roy Riascos
- Medical SchoolDepartment of Diagnostic and Interventional ImagingThe University of Texas Health Science Center Houston TX
| | | | - Larry A. Kramer
- Medical SchoolDepartment of Diagnostic and Interventional ImagingThe University of Texas Health Science Center Houston TX
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21
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Luo X, Li K, Jia YL, Zeng Q, Jiaerken Y, Qiu T, Huang P, Xu X, Zhang M. Abnormal of inter-hemispheric functional connectivity in elderly subjects with overweight/obesity. Obes Res Clin Pract 2018; 12:555-561. [PMID: 29396231 DOI: 10.1016/j.orcp.2018.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/22/2017] [Accepted: 01/10/2018] [Indexed: 10/18/2022]
Abstract
BACKGROUND There is a growing literature documenting a variety of brain abnormalities associated with obesity. However, little is known about the effects of obesity on inter-hemispheric connectivity in aging people. METHODS Participants included 61 cognitively intact elderly (including people with obesity, overweight, and lean controls) who underwent structural MRI, resting-state functional magnetic resonance imaging (rsfMRI) and standard neuropsychological batteries. Techniques including FreeSurfer and Voxel-mirrored Homotopic Connectivity (VMHC) were employed to evaluate inter-hemispheric structural and functional connectivity respectively. RESULTS There were no differences of cognitive abilities and vascular risks among groups. When compared to lean controls, obese group had greater VMHC in fusiform gyrus (FG); while overweight group had greater VMHC in FG, calcarine gyrus, inferior temporal gyrus (ITG), and postcentral gyrus (PCG). Moreover, the obesity group had lower VMHC in calcarine gyrus and PCG than overweight group (p<0.05, corrected). CONCLUSIONS The present study suggested, increased inter-hemispheric information transmission in networks supporting visual and sensorimotor function may lead to gain in weight, by possibly mediating diet behaviours of individuals.
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Affiliation(s)
- Xiao Luo
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Kaicheng Li
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Y L Jia
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Qingze Zeng
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Yerfan Jiaerken
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Tiantian Qiu
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Peiyu Huang
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaojun Xu
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Minming Zhang
- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.
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- Department of Radiology, the 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
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22
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Wang F, Jiang J, Zhang J, Wang Q. Predicting pituitary stalk position by in vivo visualization of the hypothalamo-hypophyseal tract in craniopharyngioma using diffusion tensor imaging tractography. Neurosurg Rev 2017; 41:841-849. [DOI: 10.1007/s10143-017-0933-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 11/06/2017] [Accepted: 11/21/2017] [Indexed: 12/30/2022]
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23
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MRI-derived diffusion parameters in the human optic nerve and its surrounding sheath during head-down tilt. NPJ Microgravity 2017. [PMID: 28649640 PMCID: PMC5479856 DOI: 10.1038/s41526-017-0023-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
More than half of astronauts present with significant neuro-ophthalmic findings during 6-month missions onboard the International Space Station. Although the underlying cause of this Microgravity Ocular Syndrome is currently unknown, alterations in cerebrospinal fluid dynamics within the optic nerve sheath may play a role. In the presented study, diffusion tensor imaging was used to assess changes in diffusivity of the optic nerve and its surrounding sheath during head-down tilt, a ground-based model of microgravity. Nine healthy male subjects (mean age ± SD: 25 ± 2.4 years; mean body mass index ± SD: 24.1 ± 2.4 kg/m2) underwent 5 head-down tilt conditions: −6°,−12°, −18°,−12° and 1% CO2, and −12° and lower body negative pressure. Mean diffusivity, fractional anisotropy, axial diffusivity, radial diffusivity were quantified in the left and right optic nerves and surrounding sheaths at supine baseline and after 4.5 h head-down tilt for each condition. In the optic nerve sheath, mean diffusivity was increased with all head-down tilt conditions by (Best Linear Unbiased Predictors) 0.147 (SE: 0.04) × 10−3 mm2/s (P < 0.001), axial diffusivity by 0.188 (SE: 0.064) × 10−3 mm2/s (P < 0.001), and radial diffusivity by 0.126 (SE: 0.04) × 10−3 mm2/s (P = 0.0019). Within the optic nerve itself, fractional anisotropy was increased by 0.133 (SE: 0.047) (P = 0.0051) and axial diffusivity increased by 0.135 (SE: 0.08) × 10−3 mm2/s (P = 0.014) during head-down tilt, whilst mean diffusivity and radial diffusivity were unaffected (P > 0.3). These findings could be due to increased perioptic cerebral spinal fluid hydrodynamics during head-down tilt, as well as increased cerebral spinal fluid volume and movement within the optic nerve sheath. Changes to the optic nerve and surrounding sheath during microgravity could explain why space flight is harmful to an astronaut’s vision. Darius Gerlach from the German Aerospace Center in Cologne and colleagues studied the tissue architecture of the optic nerve and its surrounding sheath in nine healthy men who experienced head-down tilt, a commonly used ground-based model of weightlessness. Using a neuroimaging technique called diffusion tensor imaging, the researchers documented fluid dynamic changes wrought by the microgravity-like conditions that could be due to alterations in the volume and movement of cerebrospinal fluid within and around the optic nerve. The findings may help explain why many astronauts experience poorer vision after long-duration space flights, although more work is needed to explore the effects of true microgravity on the visual system.
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Zhong YF, Tang ZH, Qiang JW, Wu LJ, Wang R, Wang J, Jin LX, Xiao ZB. Changes in DTI parameters in the optic tracts of macaque monkeys with monocular blindness. Neurosci Lett 2016; 636:248-253. [PMID: 27864005 DOI: 10.1016/j.neulet.2016.11.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/19/2016] [Accepted: 11/14/2016] [Indexed: 12/27/2022]
Abstract
For humans and non-human primates, the alteration of the visual pathway's white matter fibers after visual deprivation has been partially explored. However, the changes in the optic tracts after the transection of the optic nerve have not been well characterized. In the current study, we attempted to investigate the differences in optic tracts between normal and unilateral optic nerve transected macaque monkeys using diffusion tensor imaging (DTI). Four healthy neonatal macaque monkeys were randomly divided into 2 groups, with 2 in each group. Group A served as a control group, and Group B underwent unilateral (right eye) optic nerve transection to produce monocular blindness. Sixteen months (Group B16M) and thirty-two months (Group B32M) after optic nerve transection, diffusion tensor imaging was performed on all monkeys. Then, we compared fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) in bilateral optic tracts between Group A and Group B and between Group B16M and Group B32M. In both Group B16M and Group B32M, when compared with normal monkeys in Group A, FA was decreased and MD, AD and RD were increased in the bilateral optic tracts of monkeys with monocular blindness. Furthermore, compared with Group B16M, FA was reduced and MD, AD, RD were more obviously increased in the bilateral optic tracts of Group B32M, and noticeable differences in MD, AD and RD were found between the left and right optic tracts in group B32M. We believe that the results of this study would be helpful in investigation of the histological abnormalities of the integrity damage, axonal degeneration and demyelination of optic tracts in macaque monkeys with monocular blindness by DTI parameters in noninvasively and quantitatively.
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Affiliation(s)
- Yu-Feng Zhong
- Department of Radiology, Jinshan Hospital, Shanghai Medical College, Fudan University, Shanghai, China; Department of Radiology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
| | - Zuo-Hua Tang
- Department of Radiology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China.
| | - Jin-Wei Qiang
- Department of Radiology, Jinshan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
| | - Ling-Jie Wu
- Department of Otolaryngology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
| | - Rong Wang
- Department of Radiology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
| | - Jie Wang
- Department of Radiotherapy, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
| | - Li-Xin Jin
- Siemens Ltd. Healthcare Sector, Shanghai, China
| | - Ze-Bin Xiao
- Department of Radiology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
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Wu Y, Sun D, Wang Y, Wang Y. Subcomponents and Connectivity of the Inferior Fronto-Occipital Fasciculus Revealed by Diffusion Spectrum Imaging Fiber Tracking. Front Neuroanat 2016; 10:88. [PMID: 27721745 PMCID: PMC5033953 DOI: 10.3389/fnana.2016.00088] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Accepted: 09/09/2016] [Indexed: 12/20/2022] Open
Abstract
The definitive structure and functional role of the inferior fronto-occipital fasciculus (IFOF) are still controversial. In this study, we aimed to investigate the connectivity, asymmetry, and segmentation patterns of this bundle. High angular diffusion spectrum imaging (DSI) analysis was performed on 10 healthy adults and a 90-subject DSI template (NTU-90 Atlas). In addition, a new tractography approach based on the anatomic subregions and two regions of interest (ROI) was evaluated for the fiber reconstructions. More widespread anterior-posterior connections than previous “standard” definition of the IFOF were found. This distinct pathway demonstrated a greater inter-subjects connective variability with a maximum of 40% overlap in its central part. The statistical results revealed no asymmetry between the left and right hemispheres and no significant differences existed in distributions of the IFOF according to sex. In addition, five subcomponents within the IFOF were identified according to the frontal areas of originations. As the subcomponents passed through the anterior floor of the external capsule, the fibers radiated to the posterior terminations. The most common connection patterns of the subcomponents were as follows: IFOF-I, from frontal polar cortex to occipital pole, inferior occipital lobe, middle occipital lobe, superior occipital lobe, and pericalcarine; IFOF-II, from orbito-frontal cortex to occipital pole, inferior occipital lobe, middle occipital lobe, superior occipital lobe, and pericalcarine; IFOF-III, from inferior frontal gyrus to inferior occipital lobe, middle occipital lobe, superior occipital lobe, occipital pole, and pericalcarine; IFOF-IV, from middle frontal gyrus to occipital pole, and inferior occipital lobe; IFOF-V, from superior frontal gyrus to occipital pole, inferior occipital lobe, and middle occipital lobe. Our work demonstrates the feasibility of high resolution diffusion tensor tractography with sufficient sensitivity to elucidate more anatomical details of the IFOF. And we provides a new framework for subdividing the IFOF for better understanding its functional role in the human brain.
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Affiliation(s)
- Yupeng Wu
- Department of Neurosurgery, The First Affiliated Hospital of China Medical University Shenyang, China
| | - Dandan Sun
- Department of Cardiovascular Ultrasound, The First Affiliated Hospital of China Medical University Shenyang, China
| | - Yong Wang
- Department of Neurosurgery, The First Affiliated Hospital of China Medical University Shenyang, China
| | - Yibao Wang
- Department of Neurosurgery, The First Affiliated Hospital of China Medical University Shenyang, China
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Oliver J, Abbas K, Lightfoot JT, Baskin K, Collins B, Wier D, Bramhall JP, Huang J, Puschett JB. Comparison of Neurocognitive Testing and the Measurement of Marinobufagenin in Mild Traumatic Brain Injury: A Preliminary Report. J Exp Neurosci 2015; 9:67-72. [PMID: 26351409 PMCID: PMC4517832 DOI: 10.4137/jen.s27921] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/01/2015] [Accepted: 06/04/2015] [Indexed: 11/24/2022] Open
Abstract
The evaluation of concussed athletes, including testing to determine if and when they may return to play, has become an important task of athletic trainers and team physicians. Currently, concussion protocols are in place, which depend largely upon assessments based upon neurocognitive testing (NCT). The authors have evaluated the use of a biomarker of brain trauma, marinobufagenin (MBG), and compared its application in concussed athletes with the performance of NTC. We found a disparity between these two testing procedures. In this communication, the findings of these comparative data are presented. We noted that athletes whose NCT evaluations had returned to baseline and who were allowed to again participate in play then showed a recurrence of elevated urinary MBG excretion. These observations raise concern as to the processes currently in effect with regard to the decision as to returning athletes to the full activity. They suggest a need for further evaluation.
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Affiliation(s)
- Joel Oliver
- Department of Pathobiology, College of Veterinary Medicine and Biosciences, Texas A&M University, College Station, TX, USA
| | - Kamran Abbas
- Department of Pathobiology, College of Veterinary Medicine and Biosciences, Texas A&M University, College Station, TX, USA
| | - J Timothy Lightfoot
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, USA
| | - Kelly Baskin
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, USA
| | - Blaise Collins
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, USA
| | - David Wier
- The Department of Athletics, Texas A&M University, College Station, TX, USA
| | - Joe P Bramhall
- The Department of Athletics, Texas A&M University, College Station, TX, USA
| | - Jason Huang
- The Department of Neurosurgery, Baylor Scott & White Healthcare and Texas A&M Health Science Center College of Medicine, Temple, TX, USA
| | - Jules B Puschett
- Department of Pathobiology, College of Veterinary Medicine and Biosciences, Texas A&M University, College Station, TX, USA
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Keser Z, Ucisik-Keser FE, Hasan KM. Quantitative Mapping of Human Brain Vertical-Occipital Fasciculus. J Neuroimaging 2015; 26:188-93. [PMID: 26073705 DOI: 10.1111/jon.12268] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 05/03/2015] [Indexed: 11/29/2022] Open
Abstract
PURPOSE The vertical-occipital fasciculus (VOF), historically named as "the fasciculus occipitalis verticalis of Wernicke," has been recently brought to the attention of the neuroscience community. In this study, we delineated and quantified this tract with deterministic diffusion tensor imaging protocol. METHODS Five (all males aged 24-37 years) and 10 (7 males and 3 females aged 20-51 years) right-handed healthy subjects were studied with 1 and 2 mm DT-MRI data sets, respectively. The DTI attributes of this pathway along with its cortical representation (Brodmann areas) were presented in standard Montréal Neurological Institute space. Nearby pathways such as inferior fronto-occipital (IFOF) and inferior longitudinal fasciculi (ILF) were used as reference pathways. RESULTS The total volume of VOF has been found to be approximately .8-1% of whole brain in both data sets. The fractional anisotropy and axial diffusivity of this tract have been found to be relatively 10-15% lower than adjacent pathways such as IFOF and ILF in both data sets. Although IFOF and ILF showed somewhat leftward asymmetry in diffusivity, no right-left asymmetry has been observed in VOF. CONCLUSION We believe that our work will pave the way for future imaging studies investigating VOF in different conditions such as stroke, traumatic brain injury, and multiple sclerosis.
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Affiliation(s)
- Zafer Keser
- Department of Physical Medicine and Rehabilitation and TIRR Memorial Hermann Neurorecovery Research Center, University of Texas Health Science Center, Houston, TX
| | | | - Khader M Hasan
- Department of Diagnostic and Interventional Radiology, University of Texas Health Science Center, Houston, TX
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