[Topography, size and number of cortical tubers in tuberous sclerosis with West syndrome].

To predict the prognosis of tuberous sclerosis with West syndrome, we studied the relation between the cortical tubers and the neurological evolution. We reviewed the clinical data on the seizure evolution and developmental status of 7 patients (3 males and 4 females) and estimated the number, size and location of cortical tubers on 5 mm-thick T2-weighted MR images. The cortical tubers were grouped into categories: small (10 mm or less in maximum diameter), medium (10 to 25 mm) and large (25 mm or more). The first MRI study was performed at ages form 3 months to 18 years, and the follow-up study was performed on 6 out of the 7 patients. We also estimated the interval change of cortical tubers. The average number of cortical tubers was 12.1 per patient, being larger than the values previously reported for the patients of tuberous sclerosis without West syndrome. However, the numbers varied widely from 1 to 29. Two patients with good outcome had more than 10 tubers, whereas two patients with poor outcome had less than 5 tubers. All the patients with good outcome were female. Follow-up MRI in one patient revealed a marked increase in the number of cortical tubers, from 15 (at the age of 5 months) to 23 (at 4 years 2 months), which probably resulted from physiological hypomyelination during infancy. Some tubers corresponded to a electroencephalographic focus, whereas others did not. There was no difference in the topography of cortical tubers between the patients with good prognosis and those with poor prognosis. Thus, it was hard to make the prognosticate a case of tuberous sclerosis based solely on the number and topography of cortical tubers on MRI.