Ear
Middle ear and inner ear tumors - benign / nonneoplastic
Otosclerosis
Author: Nat Pernick, M.D.
Last author update: 1 October 2013
Last staff update: 15 December 2020
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: Otosclerosis [title] review[ptyp]
Table of Contents
Definition / general | Treatment | Gross description | Microscopic (histologic) description | Additional referencesCite this page: Pernick N. Otosclerosis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/earotosclerosis.html. Accessed April 24th, 2024.
Definition / general
- Disorder of bone remodeling affecting bony labyrinth and stapes footplate
- Does not appear to occur outside temporal bone (Am J Otol 1999;20:162)
- Causes fixation of stapes footplate in oval window and inability to transmit sound waves manifesting as conductive hearing loss
- Usually women; 50% have family history; begins in teenagers and slowly progresses
- More common in whites than blacks, Asians or Native Americans
- Associated with measles virus (Ann Otol Rhinol Laryngol 2001;110:897)
- 85% bilateral
Treatment
- Stapedectomy (correction of fixation of footplate of stapes)
Gross description
- Specimens are usually head and crura of stapes which are not affected by disease
Microscopic (histologic) description
- Initially bone resorption and replacement by cellular fibrovascular tissue around blood vessels; then immature bone is deposited with continuous resorption and remodeling; over time, bone is deposited with increased collagen and reduced ground substance resulting in densely sclerotic bone with prominent cement lines
