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Updated: Jun 23, 2026
The Microscopic Transcanal Approach in Stapes Surgery Revisited
Published on: February 16, 2022
Histopathology of nonotosclerotic stapes fixations
Tamás Karosi1, Péter Csomor, Mihály Petkó
1Department of Otolaryngology Head and Neck Surgery, University Medical School of Debrecen, Debrecen, Hungary. karosi@freemail.hu
Hypothesis:
Different diseases without exact histopathologic classification can cause stapes ankylosis.
Background:
Otosclerosis is a complex bone remodeling disorder of the otic capsule due to persisting measles virus infection and consecutive inflammatory reaction. In fact, clinical and demographic features of otosclerosis have reference to stapes ankylosis. In the clinical practice, otosclerosis and stapes ankylosis are incorrect synonyms.
Methods:
Nonotosclerotic stapes footplates (n = 284) removed during stapedectomy were analyzed histologically. Otosclerosis was excluded during the histologic preselection (n = 437). Total RNA was extracted, and measles virus-specific reverse-transcriptase-polymerase chain reaction was performed.
Results:
Nonotosclerotic stapes ankylosis was associated with total absence of measles virus RNA. Six main types of nonotosclerotic stapes fixations could be distinguished histologically: annular calcification (n = 152; 53.5%), globular fibrosis (n = 49; 17.25%), lymphocytic infiltration (n = 31; 10.9%), hemosiderosis (n = 22; 7.75%), granulomas (n = 17; 6%) and amyloidosis (n = 13; 4.6%). Fragmentation of nonotosclerotic stapes footplates was infrequent (7%) during stapes surgery. Only 1 floating footplate (0.35%) was reported.
Conclusion:
Two thirds of nonotosclerotic stapes footplates represented complete pathologic bone remodeling. Unlike otosclerosis, nonotosclerotic stapes fixations were characterized by basic histopathologic findings without organ specificity that can also be identified in case of different diseases. Prevalence of nonotosclerotic stapes ankylosis is approximately 30 to 40% among stapes fixation cases. The long-term prognosis and surgical considerations theoretically differ from those of otosclerosis.
Insights
Nonotosclerotic stapes ankylosis, distinct from otosclerosis, presents diverse histopathologic findings and lacks measles virus RNA. This condition accounts for a significant portion of stapes fixation cases, requiring different management strategies.
Area of Science:
- Otolaryngology
- Pathology
- Virology
Background:
- Otosclerosis is a bone remodeling disorder linked to measles virus, often confused with stapes ankylosis.
- Stapes ankylosis can result from various diseases, not solely otosclerosis.
- Accurate differentiation is crucial for appropriate clinical management.
Purpose of the Study:
- To investigate the histopathologic characteristics of nonotosclerotic stapes ankylosis.
- To determine the presence of measles virus in these cases.
- To differentiate nonotosclerotic stapes ankylosis from otosclerosis.
Main Methods:
- Histological analysis of 284 nonotosclerotic stapes footplates.
- Exclusion of otosclerosis cases (437 initially evaluated).
- Measles virus RNA detection using reverse-transcriptase-polymerase chain reaction.
Main Results:
- Nonotosclerotic stapes ankylosis showed no evidence of measles virus RNA.
- Six distinct histological types of nonotosclerotic stapes fixation were identified, including annular calcification and globular fibrosis.
- Pathologic bone remodeling was observed in two-thirds of nonotosclerotic cases.
Conclusions:
- Nonotosclerotic stapes fixations exhibit varied histopathologic features without organ specificity.
- These findings differ significantly from otosclerosis, which is associated with measles virus.
- Nonotosclerotic stapes ankylosis represents 30-40% of stapes fixation cases, necessitating distinct therapeutic approaches.
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