QUANTITATIVE MAGNETIC-RESONANCE-IMAGING IN PATIENTS WITH TEMPORAL-LOBE EPILEPSY

Quantitative brain changes on magnetic-resonance-weighted imaging (MRI) were studied in 30 patients with temporal lobe epilepsy (TLE) who showed negative findings on computed tomography and no visible abnormality on MRI, and 20 healthy controls in order to detect changes not visible by standard imaging. The patients with TLE showed a significant decrease in size and a significant increase in T1 values of the mesial temporal area in both hemispheres compared to controls who had normal values bilaterally. Patients with a current or past history of organic delusional disorder (ICD-10) resembling schizophrenia showed a significant increase in the size of the third ventricle. The data suggest that (a) there are atrophic changes in the mesial temporal areas of patients with TLE, reflecting an increased water content in these areas, (b) TLE patients often have bilateral atrophic changes in the mesial temporal areas, even if there is only unilateral abnormality of EEG, and (c) TLE patients with schizophrenia-like organic symptoms may have some structural changes around the third ventricle, including limbic system structures. Further research needs to clarify the exact structures involved and the factors responsible for these abnormalities.