Congenital anomalies of the inner ear: introducing a new classification of labyrinthine anomalies.

In a literature review of 108 articles a special effort was made to find and classify inner ear anomalies and diseases associated with inner ear anomalies. This study showed the following. Most of the diseases associated with inner ear anomalies are also associated with anomalies in other parts of the body. Hereditary characteristics comprise the most common etiological factor among the diseases associated with inner ear anomalies. Among anomalies observed in the cochlea, the vestibule, and the semicircular canals, anomalies in the cochlea are most frequently associated with various diseases and were observed in 30 of 40 diseases. Anomalies of the vestibule were observed in 25 diseases, and those of the semicircular canals in 18 diseases. Anomalies in both the osseous and the membranous labyrinth were most frequently associated with the diseases studied, as they were observed to occur with 10 of the 43 diseases. In this paper a new classification system for labyrinthine anomalies is introduced, based on this study of the literature.