[Morphologic characteristics of cortical synapses in patients with epilepsy]

Ultrastructural examination of 70 human cerebral cortex specimens was carried out. The material was obtained during operations for brain tumours in patients with or without epileptic attacks and during stereotaxic biopsy for unexplained epilepsy (E). Morphometric techniques were employed in the study. The findings were processed statistically. In tumours without E synaptic vesicles were light, uniformly distributed in the axoplasm, of rounded oval shape, and filled the presynaptic process by 80.6 +/- 1.6%. When tumours were attended by epileptic attacks there were considerable alterations in the form, size, distribution and osmiophilia of the vesicles, including polymorphism, hypertrophy, accumulation predominantly at the presynaptic membrane or aggregation, pronounced osmiophilia of the capsule, "fringed vesicles", general osmiophilia. The number of vesicles was decreased (54.2 +/- 1.4%).