Anatomical consideration of the temporal bone as a pathogenesis of Bell's palsy.

Much controversy surrounds the etiology and management of Bell's palsy, and the pathogenetic mechanisms underlying Bell's palsy remain obscure despite the extensive body of relevant research. The pathological condition of Bell's palsy is almost an inflammatory reaction compressing the facial nerve in the fallopian canal, particularly in the narrowest labyrinthine segment, followed by demyelinating neural change. As one of the best method for the visualization of the inflamed facial nerve in the intratemporal segment, temporal bone CT enable us not only to measure the exact length and thickness of individual segments of the facial nerve canal but also to view variable anatomic variations in the intratemporal facial canal. Some suggest that anatomical variation may predispose the nerve to inflammatory processes and also there can be peculiar structures of the temporal bone that are vulnerable to inflammation or neural compression injury.