Cyst-like cortical tubers in patients with tuberous sclerosis complex: MR imaging with the FLAIR sequence

Background: Tuberous sclerosis complex (TSC) is an inherited disorder characterized by the presence of cortical tubers, the majority of which are solid and show high signal on FLAIR images. Low-signal tubers are less frequent. Objective: To evaluate cystic cortical tubers in patients with TSC on the basis of their appearance on FLAIR images. Materials and methods: MR examinations of 73 patients were retrospectively reviewed and 17 children (aged 25 days to 12.3 years) with a typical cyst-like tubers were selected for further analysis. The age of the patients, the number of lesions, and the shape and MR intensity were analyzed. Results: Cyst-like cortical tubers were detected in 82% of children below 7 years of age and in 18% of those older then 7 years (P=0.00086). Most of the cystic lesions were of the shrunken type (72%), the expansile type being less frequently seen (28%). Conclusions: FLAIR images confirm the cystic character of some of the cortical tubers in TSC patients although the pathogenesis of cystic change is still unknown.