Early diagnosis of subependymal giant cell astrocytoma in children with tuberous sclerosis

Objectives-Intraventricular astrocytomas (subependymal giant cell astrocyto mas) of tuberous sclerosis have a poor prognosis due to the obstruction of CSF flow. The aim of this study was to determine whether they could be diff erentiated during childhood and at an early preclinical stage, from subepen dymal nodules without any growing potential. Methods-The first two MRIs of all children referred to this neuropaediatric centre between 1987 and 1996 were retrospectively blindly reviewed. Results-Out of 60 patients, 24 disclosed subependymal nodules localised nea r the foramen of Monro, and eight of the 24 developed astrocytomas. Subepen dymal nodules were first detectable on MRI from 1 year of age in all cases and the first MRI evidence of growth occurred between 1 and 9 years (mean 4 years). At an early stage, subependymal nodules had different characterist ics in patients who developed subependymal giant cell astrocytomas from tho se who did not. The nodules over 5 mm in diameter that were incompletely ca lcified and enhanced by gadolinium were at higher risk of growing, particul arly in children with a familial history of tuberous sclerosis. To detect the subependymal giant cell astrocytomas earlier in tuberous scle rosis, it is advisible to systematically perform an MRI examination before 2 years of age and to repeat it every year if the patient has risk factors for developing astrocytomas.