Ultrastructural Aspects of the Human Peripheral Vestibular System

Abstract

Gleeson MJ, Felix H, Johnsson LG. Ultrastructural aspects of the human peripheral vestibular system. Acta Otolaryngol (Stockh) 1990; Suppl. 470: 80–87.

The sensory epithelia from the membranous labyrinths of 4 patients were examined by transmission electron microscopy. the distribution ratio of type 1 to type 2 cells was recorded, compared for each sensory area and correlated with age. An ultrastructural assessment confirmed generalized patterns consistent with autolytic and preparation artefact, viz. calyceal dilatation, cytoplasmic protrusions and some sensory hair loss. More specific features, i.e. lipofuscin accumulation, membrane-bound inclusions and neural degeneration were consistent with pre-mortem pathological change. in 2 patients, total nerve fibre counts of 15,766 and 19,741 were obtained. Total fibre counts correlated with the sensory cell density of the innervated areas. Differential counts of the superior and inferior vestibular nerves suggested that there was a reduced number of fibres in the superior division of both patients, in comparison with established normative data. Morpho-metric analysis of the constituent fibre diameters revealed a skewed distribution with a modal value of 6 μm for both patients.

Key Words:

• ultrastructure
• vestibular system
• human
• transmission electron microscopy
• ageing