ABSTRACT
PURPOSE: It has been suggested that recurrent seizures may cause the hippocampal formation (HF) damage in temporal lobe epilepsy (TLE). To evaluate whether secondarily generalized tonic clonic seizure (SGTC) is related to the degree of the HF damage on MRI we performed this study. METHODS: We found 42 patients with TLE who had HS on qualitative MRI from epilepsy database. They were divided into unilateral HS (UHS) and bilateral HS (BHS) on qualitative MRI by visual analysis. We performed HF volumetry in 20 and T2 relaxometry in 22 (17 patients were lateralized by quantitative MRI and ictal or interictal EEG). RESULTS: The frequency of status epilepticus and SGTCs in BHS were significantly higher than that in UHS (14% vs 3%, p<0.05 and 60% vs 6%, p<0.05 respectively). Of 17 patients who were lateralized, the frequency of SGTCs was significantly correlated to the ipsilateral (r=0.58, p<0.05) and contralateral (r=0.35, p<0.05) T2 relaxometry as well as inversely to the ipsilateral (r=-0.59, p<0.05) and contralateral (r=-0.52, p<0.05) HF volume. CONCLUSIONS: BHS has the higher frequency of status epilepticus and SGTCs, and the frequency of SGTCs was related to the HF damage.