Structural patterns of injured mitochondria in human oedematous cerebral cortex

Abstract

Primary objective: Cerebral cortical biopsies of 37 patients with clinical diagnosis of congenital malformations, brain trauma and tumours were studied to establish mitochondrial morphological alterations.

Methods and procedures: Cortical biopsies obtained in the surgical room were immediately processed by conventional technique for transmission electron microscopy.

Results: Three injured mitochondrial morphological patterns were found: swollen clear, (SCM), swollen dense (SDM) and dark degenerated (DDM) mitochondria. SCM were predominantly found in traumatic brain oedema. SDM and DDM were frequently observed in sustained permanent ischaemia induced by brain tumours, vascular anomaly and congenital hydrocephalus. SCM exhibited low electron dense mitochondrial matrix, enlarged intracristal space and continuity of outer and inner mitochondrial membranes. SDM showed high electron dense matrix and swollen intact or fragmented cristae. DDM displayed overall high electron density of matrix and mitochondrial membranes.

Conclusion: The injured mitochondrial patterns are related with nerve cell death and considered markers of lethal nerve cell injury.