Stapes fixation to the promontory and fallopian canal in a case of chronic otitis media: Implications on development and etiology

Abstract

Embryology of stapes has long been a topic of controversy. There are theories stating a single source to the dual origin of stapes. Chronic otitis media is also known to cause various acquired bony ossicular fixations. We present a case of an 11-year-old female with right chronic otitis media, active squamosal with cerebellar abscess who underwent drainage of cerebellar abscess followed by tympanomastoidectomy as a two-staged procedure. Intraoperatively, there were stapes suprastructure fusion to the fallopian canal and one crural attachment to the promontory. There are no clear criteria to differentiate bony fixation of congenital origin from acquired causes. This case also highlights the need to add a new subclass in the classification of minor middle ear anomalies given by Cremer, and our findings also support the dual origin for stapes development.