HISTOLOGICAL ANATOMY OF THE HUMAN TEMPORAL BONE FOR EAR SURGERY

Abstract

　Learning the anatomy of human temporal bone histology is fundamental to otology. The knowledge of histological anatomy in addition to macroscopic anatomy enables safe and sufficient surgery. The preparation of human temporal bone histological specimens requires a great deal of time, effort, and expense, and the specimens that have been stored in Japan are extremely valuable.

　There are two directions for sectioning of the temporal bone: horizontal section and vertical section. The horizontally sectioned specimens are suitable for observation of the incudomallear joint, whole route of the facial nerve, cochlea, anterior and posterior semicircular canals, saccular macula, round window, vestibular aqueduct, and endolymphatic sac. On the other hand, the vertically sectioned specimens are convenient for observing the whole eustachian tube, cochlea, facial nerve from the labyrinthine to the tympanic portions, tensor tympani muscle, ampullae of the superior and lateral semicircular canals, utricular macula, and round window.

　Currently, human temporal bone histopathological research has been diminishing around the world. However, immunohistological and molecular biological analyses have been adopted on the research and archival temporal bone specimens are likely to provide new insights into the pathogenesis of ear diseases.