PATHWAYS OF INFECTION IN LABYRINTHITIS: REPORT OF THREE DIFFERENT TYPES

Abstract

Inflammation of the bony and membranous labyrinth, as is well known, is seldom primary. It usually results as a secondary involvement from without. The most common pathway of infection into the labyrinth is secondary to involvement of the middle ear. In the majority of cases, the infection enters through the windows, i. e., the oval window and the round window. From an anatomic standpoint, it would appear that the entrance should be more common through the round window, that is, through the membrana secondaria situated at the niche of the round window. This membrane is much longer than the annular ligament at the oval window and is more exposed. Although the membrane consists of thick strands of fibrous tissue, it may at times be thin and may offer little resistance to the infectious process in the middle ear (Wittmaack ¹). The oval window, on the other hand, is protected