Dual inversion recovery MRI helps identifying cortical tubers in tuberous sclerosis

Purpose: Dual inversion-recovery imaging (DIR) has been advocated for the diagnosis of cortical lesions in epileptic patients. The role of this sequence, however, is not established in tuberous sclerosis patients. Methods: We studied prospectively the interest of DIR sequence in four well-documented consecutive tuberous sclerosis patients with focal epilepsy. Results: In all patients, the cortical tubers appeared very bright on this sequence and were well outlined compared with high resolution T2 or FLAIR imaging. In two patients, one cortical tuber was missed on T-2 weighted images due to signal intensity close to the CSF. These lesions were better depicted on DIR than on FLAIR. Three cortical lesions from two patients were visualized only on DIR. Conclusion: DIR helped to depict cortical tubers and may have a complementary role in the MRI evaluation of tuberous sclerosis patients. There is a need to compare sensitivity of T2, FLAIR and DIR with a larger population of patients with focal epilepsies.