Ultrastructural pathology of human hydrocephalic cerebral cortex

Abstract

The ultrastructural pathology of cerebral cortex in human hydrocephalus is described. Cortical biopsies of 17 patients of ages ranging from 10 days to 21 years old examined in our laboratory are described. Nerve cells show moderate and severe swelling characterized by dilation of endoplasmic reticulum canaliculi and perinuclear cistern, edema and degenerative changes of Golgi apparatus, variable degrees of mitochondrial swelling, and fragmentation of plasma membrane. The neighboring neuropil exhibits notable enlargement of extracellular space and signs of synaptic plasticity and degeneration. The astrocytes display edematous changes and phagocytic activity. Glycogen rich- and glycogen-depleted astrocytes are observed. Oligodendroglial cells appear normal in certain cases and in others show moderate hydropic changes. Numerous myelin figures are observed in some unidentified nerve cell processes. The capillary wall shows evident signs of blood-brain barrier dysfunction featured by increased endothelial vesicular and vacuolar transport, closed and open interendothelial junctions, and in severely edematous areas thinning and breakdown of capillary basement membrane. The role of ischemia, oxidative stress, increased calcium concentration, activation of N-methyl-d-aspartate (NMDA) receptors, and disturbance of ion homeostasis are discussed in relationship with the fine structural alterations of hydrocephalic brain parenchyma.

Keywords

Human hydrocephalus - nerve cell damage - synaptic plasticity - synaptic degeneration - reactive glial cells - extracellular space - electron microscopy