Päivi Koskenkorva MD, Presenter: Nothing to Disclose

Kimmo Lehtimäki, Abstract Co-Author: Nothing to Disclose

Mervi Kononen MSc, Abstract Co-Author: Nothing to Disclose

Esa Mervaala MD, PhD, Abstract Co-Author: Nothing to Disclose

Reetta Kälviäinen, Abstract Co-Author: Nothing to Disclose

Ritva Liisa Vanninen MD, Abstract Co-Author: Nothing to Disclose

Eini Niskanen MSc, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Unverricht-Lundborg disease (ULD), progressive myoclonic epilepsy type 1 (EPM1, OMIM254800) caused by mutations of the cystatin B (CSTB) gene, is a rare autosomal recessive neurodegenerative disorder characterized by age of onset from 6-16 years, stimulus-sensitive myoclonus, and tonic-clonic epileptic seizures. The purpose of this study was to evaluate the possible changes in gray matter volumes and white matter fractional anisotropy (FA) in ULD patients.

Thirty patients with genetically verified ULD (4 compound heterozygotes, 26 homozygotes for mutations in CSTB) underwent MRI (1.5 Tesla, Siemens Avanto). MR imaging included T1- and T2-weighted spin-echo sequences, fluid attenuated inversion recovery sequence (FLAIR), T1-weighted three-dimensional images, MR spectroscopy and diffusion tensor imaging (DTI, n=20). Motion correction software was used if necessary. Regional changes in gray matter volume were analyzed from the T1-3D images using optimized voxel-based morphometry (VBM) and statistical parametric mapping (SPM2 running under Matlab 6.5) and compared with matched controls (n=30). Voxelwise analysis with tract-based spatial statistics (TBSS, cluster-level inference at t > 2.2, p < 0.05) was used to compare FA among patients and matched controls.

Conventional images revealed no focal abnormalities. In VBM (p<0.05), ULD patients showed cortical gray matter atrophy in primary, premotor and supplementary motor cortex, bilateral cuneus, precuneus and thalamus, compared to controls. No differences were seen in cerebellum or brain stem. In TBSS, ULD patients showed significantly decreased FA in pyramidal tracts and corpus callosum compared to controls (p < 0.05, corrected).

Significant decrease in FA in pyramidal tracts correlates with the motor symptoms of Unverricht-Lundborg disease. The finding is also consistent with the VBM findings of gray matter volume loss in cortical motor areas.

Detailed MR imaging together with neurophysiologic evaluation may help to reveal the pathogenesis of Unverricht-Lundborg disease.

Koskenkorva, P, Lehtimäki, K, Kononen, M, Mervaala, E, Kälviäinen, R, Vanninen, R, Niskanen, E, et al, , Unverricht-Lundborg Disease (ULD): Diffusion Tensor Imaging and Voxel-based Morphometry Reveal Bilateral Abnormalities in Pyramidal Tracts, Primary Motor, and Premotor Cortices.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6008941.html