[Relationship between imaging and pathological features and clinical factors in surgical cases of temporal lobe...

The relationships between imaging, pathology and presumed causes in surgical cases of temporal lobe epilepsy (TLE) was studied. The subject was 62 patients (33 males and 29 females) who had had no attacks for more than one year after surgery. Average age at surgery was 28.2 +/- 9.9 years. Obvious neurological abnormalities were not found in these cases. MRI, PET and SPECT were performed. Hematoxylin and eosin was used for pathological judgement. Their medical charts were used to investigate their clinical factors. Although patients suspected of having encephalitis/meningitis had been hospitalized for 2 days to three months during childhood due to disturbance of consciousness with high fever and convulsion for several days; they were not diagnosed with encephalitis/meningitis at that time, and they suffered almost no handicaps other than epilepsy for several years following their comatose episodes. [Result] (1) On MRI, mesial temporal sclerosis (MTS) was detected in 48 of 52 patients (92%); 32 (62%) had high-signal intensity on T 2-weighted images; 31 (60%) had atrophy ¿23 (44%) had high-signal intensity on T 2 + atrophy¿; 5 (10%) had calcified lesions; and 2 (4%) had cystic lesions. On PET and SPECT, abnormal cerebral blood flow was noted in 33 of 36 (92%). (2) On pathological findings (61 cases), Ammon's horn sclerosis (AHS), tumors, gliosis in lateral temporal and meningeal inflammatory finding were detected in 42 (69%), 10 (23%) and 8 (13%) cases, respectively, whereas 2 showed no abnormalities. The 2 patients with normal pathology showed both high-signal intensity and atrophy on MRI. (3) The presumed causes of TLE were encephalitis/meningitis and/or suspected of these diseases in 15 patients (24%), injuries at birth in 5 (8%), and none in 42 (68%). The presumed causes in the 43 patients with AHS were encephalitis/meningitis in 11, injuries at birth in 3, and none in 29. Of the 15 patients in whom encephalitis/meningitis was estimated as the causes of TLE, only 6 (40%) had pathological evidence of meningeal inflammatory finding. Of the 42 patients in whom cause could not be determined, 2 had pathological evidence of meningeal inflammatory finding.