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Dissection of the Auditory Bulla in Postnatal Mice: Isolation of the Middle Ear Bones and Histological Analysis
Published on: January 4, 2017
Histopathologic study of the temporal bones and Eustachian tubes of children with cholesterol granuloma
Makoto Miura1, Isamu Sando, Yorihisa Orita
1Department of Otolaryngology, University of Pittsburgh School of Medicine, Pennsylvania 15213, USA.
Insights
Cholesterol granuloma in children may stem from persistent mesenchyme and eustachian tube dysfunction. This dysfunction hinders middle ear ventilation, promoting cholesterol granuloma development.
Area of Science:
- Otolaryngology
- Pediatric Pathology
- Histopathology
Background:
- Cholesterol granuloma (CG) is a rare condition often associated with chronic otitis media.
- Understanding the pathogenesis of CG in pediatric populations is crucial for effective management.
Observation:
- Histopathological study of six pediatric temporal bone-eustachian tube specimens with CG.
- CG was observed in various middle ear spaces, including mastoid air cells and epitympanum.
- All cases showed remaining mesenchyme continuous with hematopoietic bone marrow and evidence of otitis media with effusion.
Findings:
- Three cases presented morphological abnormalities of the eustachian tube (ET), such as hypoplastic cartilage and abnormal tensor veli palatini muscle.
- In cases with ET anomalies, the posterior cartilaginous ET was filled with effusion.
- Erythrocytes in the mesenchyme likely originate from hematopoietic bone marrow.
Implications:
- Eustachian tube dysfunction appears to be a significant factor in the pathogenesis of CG in children.
- Failure of middle ear ventilation due to ET dysfunction may promote CG development.
- Further research into pediatric ET function is warranted to elucidate CG pathogenesis.
Abstract:
Six temporal bone-eustachian tube (ET) specimens with cholesterol granuloma (CG), obtained from 6 children 6 months to 15 years of age, were studied histopathologically to obtain further information about the pathogenesis of CG. We observed CG in the mastoid air cells in 5 ears, the mastoid antrum in 1 ear, the aditus ad antrum in 2 ears, and the epitympanum in 1 ear. All 6 cases exhibited a large amount of remaining mesenchyme that was in continuity with the hematopoietic bone marrow in the locations in which CG was present. All cases demonstrated otitis media with effusion and inflammation of the ET. Apparent morphological abnormalities of the ET and its associated structures, including hypoplastic ET cartilage and an abnormal tensor veli palatini muscle, were noted in 3 of the 6 cases. Furthermore, the posterior cartilaginous portion of the ET that includes its narrowest portion was completely filled with effusion in 2 of the 3 cases with the ET anomaly. The findings obtained were compared with data from age-matched control cases. Our results suggest that the source of erythrocytes in the remaining mesenchyme is the hematopoietic bone marrow. The pathogenesis of CG in children is likely promoted by ET dysfunction resulting in failure of ventilation of the middle ear.
