Abstract
BACKGROUND AND PURPOSE: The brain stem is compactly organized with life-sustaining sensorimotor and autonomic structures that can be affected by numerous pathologies but can be difficult to resolve on conventional MR imaging.
MATERIALS AND METHODS: We applied an optimized TSE T2 sequence to washed postmortem brain samples to reveal exquisite and reproducible brain stem anatomic MR imaging contrast comparable with histologic atlases. This resource-efficient approach can be performed across multiple whole-brain samples with relatively short acquisition times (2 hours per imaging plane) using clinical 3T MR imaging systems.
RESULTS: We identified most brain stem structures at 7 canonical axial levels. Multiplanar or oblique planes illustrate the 3D course and spatial relationships of major brain stem white matter pathways. Measurements of the relative position, course, and cross-sectional area of these pathways across multiple samples allow estimation of pathway location in other samples or clinical subjects. Possible structure-function asymmetries in these pathways will require further study—that is, the cross-sectional area of the left corticospinal tract in the midpons appeared 20% larger (n = 13 brains, P < .10).
CONCLUSIONS: Compared with traditional atlases, multiplanar MR imaging contrast has advantages for learning and retaining brain stem anatomy for clinicians and trainees. Direct TSE MR imaging sequence discrimination of brain stem anatomy can help validate other MR imaging contrasts, such as diffusion tractography, or serve as a structural template for extracting quantitative MR imaging data in future postmortem investigations.
ABBREVIATIONS:
- ACPC
- anterior/posterior commissure
- CST
- corticospinal tract
- CTT
- central tegmental tract
- ML
- medial lemniscus
- MLF
- medial longitudinal fasciculus
- SUDC
- sudden unexplained death of childhood
Footnotes
Disclosures: Laura Crandall—RELATED: Grant: SUDC Foundation, Comments: The SUDC Foundation of which I am President and the volunteer Executive Director provided a grant to New York University School of Medicine to perform this study. I have an agreed management plan with New York University whereby I am not involved with any grant negotiations between the Foundation and New York University. No grant funds were allocated to my work on the study*; UNRELATED: Travel/Accommodations/Meeting Expenses Unrelated to Activities Listed: SUDC Foundation, Comments: The SUDC Foundation supports my travel to medical-related meetings and awareness events not related to this study, but to SUDC in general.* Thomas Wisniewski—RELATED: Grant: National Institutes of Health, Comments: funding from National Institutes of Health National Institute on Aging grant AG008051.* Orrin Devinsky—RELATED: Grant: SUDC Foundation*; UNRELATED: Employment: New York University School of Medicine; Other: National Institutes of Health Center for Sudden Unexpected Death in Epilepsy Research on separate projects.* Timothy M. Shepherd—RELATED: Grant: National Institutes of Health National Institute on Aging, K23 AG048622*; UNRELATED: Expert Testimony: medicolegal expert testimony; Grants/Grants Pending: Brainlab, Comments: Principal Investigator, multiparametric MRI study of metastases treated with gamma knife irradiation*; OTHER RELATIONSHIPS: scientific advisor for Velona Technologies (devices for CT-guided image interventions) and MICroStruture Imaging (postprocessing tools for advanced MRI acquisitions). No payments were involved. *Money paid to the institution.
This study was funded by the SUDC Foundation and the Finding a Cure for Epilepsy and Seizures fund. T.M. Shepherd received research support from the National Institute of Aging (grant AG048622). T. Wisniewski and A. Faustin received research support from the National Institute of Aging (grant AG008051). This work was supported, in part, by the Center for Advanced Imaging Innovation and Research, a National Institutes of Health National Institute of Biomedical Imaging and Bioengineering Biomedical Technology Resource Center (grant P41EB017183).
- © 2019 by American Journal of Neuroradiology
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