Ultrastructural study of the epithelium of the normal human vulva

An ultrastructural study of the pathology of vulvar vestibulitis syndrome (Friedrich, 1987) necessitated a detailed knowledge of the epithelial surface of the vulva. As this has previously been characterised only at the light microscopy level, a comprehensive electron microscopical study of the vulva was considered critical to the study of the pathological tissue. A comparison between vulvar, vaginal and keratinised perineal epithelia, confirmed the resemblance of vulvar epithelium to partially keratinised mucosal-like epithelia. No conclusive evidence of keratinisation was observed and the characteristic granular and spiny cell layers found in skin were absent. The prominent cell type was the glycogenated intermediate cell, which formed a structurally homogeneous layer of cells. Other cell types present were: superficial flattened cells, many having nuclei, traces of organelles and large glycogen deposits; suprabasal cells; and basal cells, some of which appeared mitotically active rich in organelles. All cell layers were characterised by the presence of numerous interdigitating cytoplasmic processes, small numbers of infrequent desmosomal junctions and pale staining cytokeratin filaments.