Microstructural integrity of early‐ versus late‐myelinating white matter tracts in medial temporal lobe epilepsy. Issue 10 (13th September 2013)

• Record Type: Journal Article
• Authors: Lee, Chu‐Yu; Tabesh, Ali; Benitez, Andreana; Helpern, Joseph A.; Jensen, Jens H.; Bonilha, Leonardo
• Is Part Of: Epilepsia. Volume 54:Issue 10(2013:Oct.)
• Page Start: 1801
• Page End: 1809
• Publication Date: 2013-09-13
• Subjects: Epilepsy -- Periodicals; 616.853
• DOI: 10.1111/epi.12353
• Languages: English
• ISSNs: 0013-9580

Abstract

<abstract abstract-type="main" id="epi12353-abs-0001"> <title>Summary</title> <sec id="epi12353-sec-0001" sec-type="section"> <title>Purpose</title> <p>Patients with medial temporal lobe epilepsy (MTLE) exhibit structural brain damage involving gray matter (GM) and white matter (WM). The mechanisms underlying tissue loss in MTLE are unclear and may be associated with a combination of seizure excitotoxicity and WM vulnerability. The goal of this study was to investigate whether late‐myelinating WM tracts are more vulnerable to injury in MTLE compared with early myelinating tracts.</p> </sec> <sec id="epi12353-sec-0002" sec-type="section"> <title>Methods</title> <p>Diffusional kurtosis imaging scans were obtained from 25 patients with MTLE and from 36 matched healthy controls. Diffusion measures from regions of interest (ROIs) for both late‐ and early myelinating WM tracts were analyzed. Regional Z‐scores were computed with respect to normal controls to compare WM in early myelinating tracts versus late‐myelinating tracts.</p> </sec> <sec id="epi12353-sec-0003" sec-type="section"> <title>Key Findings</title> <p>We observed that late‐myelinating tracts exhibited a larger decrease in mean, axial, and radial kurtosis compared with early myelinating tracts. We also observed that the change in radial kurtosis was more pronounced in late‐myelinating tracts ipsilateral to the side of seizure onset.</p> </sec> <sec id="epi12353-sec-0004" sec-type="section"> <title>Significance</title> <p>These results suggest a developmentally based preferential susceptibility of late‐myelinating WM tracts to damage in MTLE. Brain injury in epilepsy may be due to the pathologic effects of seizures in combination with regional WM vulnerability.</p> </sec> </abstract>