Early single photon emission computed tomography in Sturge-Weber syndrome

OBJECTIVES—Functional cerebral imaging PET andSPECT have shown hypometabolism and hypoperfusion in the area ofvascular malformation in children with epilepsy due to Sturge-Webersyndrome. However, data are scarce in infants and do not exist inpatients with Sturge-Weber disease without epilepsy. The pattern ofperfusion during the first two years of life was studied includingpatients before the onset of seizures.
METHODS—Twenty two infants with laterconfirmed Sturge-Weber disease underwent SPECT examination usingTOMOMATIC 564 (Medimatic) and xenon-133 at ages ranging from 8 days to25 months. Twelve had never had seizures before SPECT and sevenunderwent a second SPECT a mean seven months later. Cerebral blood flow(CBF) was measured in the whole hemisphere and in the part of thecortex involved in the vascular malformation on both sidesas well as a ″pathological to normal″ index for the hemisphereand vascular malformation. These values were compared withnormal age paired values.
RESULTS—Compared with controls, CBF and theindices in the hemisphere and vascular malformation were significantlydecreased in patients who already had had seizures before SPECT,whereas they were significantly increased in 75% of the patients whohad never had any seizures. On second SPECT, the indices were decreasedin all patients, including the four who still remainednon-epileptic.
CONCLUSIONS—SPECT therefore detects CBF asymmetryin infants with Sturge-Weber disease, which tends to shift with age.The cortex involved in the vascular malformation is hyperperfusedduring the first year of life before first seizures. The classichypoperfusion appears after one year of age, even in non-epileptic patients.