Diffusion tensor imaging to visualize axons in the setting of nerve injury and recovery.
Successful management of peripheral nerve trauma relies on accurate localization of the injury and grading of the severity of nerve injury to determine whether surgical intervention is required. Existing techniques, such as electrodiagnostic studies and conventional imaging modalities, provide important information, but are limited by being unable to distinguish severe nerve lesions in continuity that will recover from those that will not. Diffusion tensor imaging (DTI) and tractography of peripheral nerves provide a novel technique to localize and grade nerve injury, by assessing the integrity of the nerve fibers across the site of nerve injury. Diffusion tensor imaging and tractography also hold promise as markers of early nerve regeneration, prior to clinical and electrodiagnostic evidence of recovery. In the present review, the techniques of peripheral nerve DTI and tractography are discussed with respect to peripheral nerve trauma, with illustrative cases demonstrating potential roles of these novel approaches.
Departments of 1 Radiology and.|Neurosurgery, Northwestern University Feinberg School of Medicine, Chicago, Illinois;
Thomas Anthony
TA
Gallagher
Prince of Wales Clinical School, University of New South Wales, Sydney; and.|Department of Neurology, St. Vincent's Hospital, Darlinghurst, New South Wales, Australia.
Neil G
NG
Simon
Neurosurgery, Northwestern University Feinberg School of Medicine, Chicago, Illinois;
Michel
M
Kliot
D000328:Adult; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D059348:Peripheral Nerve Injuries / Q000473:pathology* / Q000503:physiopathology*; D010525:Peripheral Nerves / Q000473:pathology*; D020127:Recovery of Function / Q000502:physiology*; D055815:Young Adult
DTI = diffusion tensor imaging; EMG = electromyography; FA = fractional anisotropy; MRC = Medical Research Council; MRI; TA = tibialis anterior; diffusion tensor imaging; nerve regeneration; peripheral nerve trauma; tractography