Abstracts

Rationale: Improvements in signal to noise ratio and spatial resolution by 3 Tesla magnetic resonance imaging (MRI) of the brain have the potential to improve the identification of focal abnormalities in patients with Temporal Lobe Epilepsy (TLE) Methods: : A presenting sample of 36 patients with confirmed clinical and electrographic diagnosis of epilepsy were recruited from epilepsy clinic at St James’s Hospital , Dublin Ireland. 26 of these had no identifiable, temporal lobe abnormalities on standard 1.5 Tesla MRI and 10 had lesions in the temporal lobe on 1.5 Tesla scans performed as part of their routine diagnostic work up. All 36 submitted themselves for further imaging using 3 Tesla imaging protocol. T1 weighted FSE, 3 D /T2 weighted FSE, T2 weighted FLAIR, 3 D Results: Among the non lesional group, 11 lesions were picked up. ( 4 Mesial tewmporal sclerosis, 5 subcortical white matter hyperintensities and 2 cortical dysplasia) In the lesional group, 8 additional abnormalities were detected. ( 6 sub cortical white matter hyper intensities , 1 cortical dysplasia aqnd 1 meningioma) Conclusions: : This study was aimed at comparing 1.5 T and 3 T imaging in cases of TLE with and without established mesial temporal lobe sclerosis in a real world paradigm. The findings of 3T MRI were compared to previous sets of reports issued in clinical situations. In both cohorts compared, we could find additional lesions in 19 out of 36 cases ( 52%). There were 11 additional lesions among 26 lesional cases out of which 4 were definite, 5 were possible and 2 were outside temporal lobe. In the case of lesional cohort, out of 8 lesions identified, 1 definite, 6 possible and one case of other lesion found. The abnormalities include mesial temporal sclerosis , cortical dysplasia, sub cortical white matter lesions, meningioma etc. The results are quite comparable or even superior to other recent studies1. This additional pickup has significant implications for the prognosis of surgical remediation. The use of 3Tesla MRI in a real world clinical context may significantly improve diagnostic accuracy in a minority of patients.