Abstracts

Sturge-Weber syndrome (SWS) is associated with epilepsy and progressive neurological course. However, the relation between abnormal veins, cortical damage, and neurological complications in SWS is poorly understood. Susceptibility weighted imaging (SWI) is a novel MRI technique with an exquisite sensitivity to small veins by detecting deoxygenated blood without administration of a contrast medium. Cerebral calcium deposits (often seen in SWS) also cause susceptibility changes on SWI. Therefore, SWI in conjunction with glucose metabolism positron emission tomography (PET) allows a comprehensive approach in elucidating structure-function relationships associated with abnormal hemodynamics and seizures in SWS., Fourteen children (age: 1.5-10.3 years) with SWS and unilateral leptomeningeal angioma underwent MRI with SWI and glucose metabolism PET prospectively. These images were co-registered and cortical regions showing decreased glucose metabolism in the affected hemisphere were objectively identified using an asymmetry-based method. Regions of cortical hypometabolism were compared to visually detected SWI signal abnormalities., Eleven patients had seizures, all of whom showed focal hypometabolism in the affected hemisphere, ranging from mild focal to severe multilobar hypometabolism. SWI showed: (1) cortical susceptibility changes in 9 patients; these occurred only in children with seizures and were located in hypometabolic cortical areas; (2) deep transmedullary veins consistent with collaterals connecting the brain surface with deep cerebral veins (N=10). These deep veins were located most frequently under cortex with mild hypometabolism or directly adjacent, under normometabolic cortical regions; these veins were present even in the youngest patients with no cortical SWI signal changes and also in 2 of the 3 children without seizures., Susceptibility weighted imaging (SWI) can detect cortical and fine venous abnormalities in children with SWS. Susceptibility changes in hypometabolic cortex are associated with seizures, suggesting that SWI may assist in delineation of epileptogenic cortex in children with SWS. Deep transmedullary veins occur early and persist at the border of hypometabolic cortex, probably providing collateral drainage; however, these regions may be vulnerable to progressive damage in the disease course. SWI can be a useful MRI technique to detect microstructural changes in SWS and other pediatric epilepsy syndromes associated with small venous abnormalities and/or cerebral calcification., (Supported by NIH grant RO1 NS041922 (to Dr. Juhasz).)