NEOCORTICAL DENDRITIC PATHOLOGY IN HUMAN PARTIAL EPILEPSY - A QUANTITATIVE GOLGI-STUDY

We used a computerized image-analysis system to perform a quantitative analysis of rapid Golgi-impregnated pyramidal neurons of the third co rtical layer of histologically normal cerebral cortex surgically remov ed from patients with partial epilepsy. Various parameters of 51 neuro ns from 9 patients and 29 neurons from 5 age-matched controls were com pared. Dendritic spine density decreased progressively with increasing duration of seizures, and dendritic swellings were most numerous in e pilepsy cases of uncertain etiology and in patients with seizures of l onger standing. Neurons from seizure cases showed fewer dendritic bran ching points and fewer proximal dendritic branches than those from con trols, suggesting a simplified dendritic architecture. These findings indicate that neurons in cortex distant from the primary site of epile ptogenic activity may be undergoing subtle, progressive degeneration, which may explain the propensity of chronic epilepsy patients to have increased seizure activity and interictal behavioral and cognitive abe rrations.