Ictal fear in temporal lobe epilepsy - Surgical outcome and focal hippocampal changes revealed by proton magnetic resonance spectroscopy imaging

Background: Ictal fear (IF) is most frequently associated with epileptic di scharges from mesial temporal areas. Objectives: To determine whether patients with IF were more likely to becom e seizure free after anteromesial temporal lobe resection compared with tho se without IF and whether they show more anteriorly pronounced metabolic ch anges assessed by means of multivoxel magnetic resonance spectroscopy (MRS) along the hippocampal axis. Methods: Surgical outcome was assessed in 33 consecutive patients with temp oral lobe epilepsy after a mean follow-up of 25 months (range, 12-38 months ). Proton multivoxel MRS of the hippocampal formation was applied to detect regional differences along the axis of the hippocampus in patients with an d without IF. Magnetic resonance tomography showed typical features of hipp ocampal sclerosis in all patients. Results: Twelve (36%) of the 33 patients reported fear at the beginning of their habitual seizures. Eleven of these patients were seizure free postope ratively. In contrast, only 11 of 21 patients without IF had a favorable ou tcome. Results of MRS revealed significantly higher pathologic N-acetylaspa rtate-choline ratios in the anterior portion of the hippocampal formation i n patients with than in those without IF, indicating focal metabolic and/or morphologic changes in the head of the hippocampus. Conclusions: These results indicate the importance of diagnosing auras with IF to provide a more detailed prognosis of the surgical outcome. In additi on, our data emphasize that multivoxel MRS is a valuable tool in the presur gical evaluation, as it may reveal different topographical patterns of hipp ocampal sclerosis.