OBJECTIVE: To observe the morphology of eroded auditory ossicles obtained in middle ear surgery for cholesteatoma and to investigate the mechanism of bone erosion in cholesteatoma. METHOD: The morphology of eroded auditory ossicles in 8 cholesteatoma cases and 2 normal cases were observed with light microscopy. The ultrastructure of eroded auditory ossicles in 5 cholesteatoma cases and the ultrastructure of control bones in external ear canal of 2 cases were observed and compared with transmission electron microscopy. RESULT: Osteomyelitis and multinucleate osteoclasts with ruffled borders were observed in the eroded auditory ossicles of cholesteatoma. Intramembranous and endochondral ossification were both observed. The obvious bone destruction and remodeling were observed consistently. CONCLUSION Osteoclasts and Osteomyelitis are both responsible for bone destruction in cholesteatoma. Intramembranous and endochondral ossification may co-participate in bone remodeling. Osteogenesis is also a basic pathologic phenomena in cholesteatoma. The obvious bone destruction and remodeling can coexist in cholesteatoma cases.
Case-Control Studies ; Cholesteatoma, Middle Ear ; pathology ; Ear Ossicles ; pathology ; ultrastructure ; Humans ; Microscopy, Electron, Transmission ; Osteoclasts ; pathology ; ultrastructure

OBJECTIVE: To investigate the ultrastructural changes of the mucosa of eustachian tube in mice and to reveals the influence of eustachian tube on middle ear function and its relavence with otitis media. METHOD: 12 wild type and 12 mutant mice were divided into two groups by age to observe the the ultrastructural changes of the mucosa of eustachian tube. RESULT: Wild type mice exhibited a thick lawn of morphologically normal, distributed cilia in the mucosa of the middle ear at both time points. The cilia of mucosa of middle ear in mutant mice were short, impaired and disrupted. The impairment of the cilia progressed to a much great severity at 6 months compared to 3 months. CONCLUSION Otitis media occurs not only the ciliated cells decreased and the goblet cells increased. More importantly, the ciliary structure was damaged, leading to the dysfunction of the mucociliary transport system and causing otitis media.
Animals ; Cilia ; pathology ; ultrastructure ; Disease Models, Animal ; Ear, Middle ; pathology ; Eustachian Tube ; pathology ; ultrastructure ; Goblet Cells ; Mice ; Microscopy, Electron, Scanning ; Mucociliary Clearance ; Mucous Membrane ; pathology ; ultrastructure ; Otitis Media ; pathology

To understand better the pathogenesis of inner ear (IE) damage caused by otitis media (OM), the round window membrane(RWM) structure was investigated in a rat model for pneumococcal otitis media (POM). The RWM of 25 rats were evaluated light and electron microscopically on 1 day, 3 days, 6 days, 10 days, and 20 days after the unilateral inoculation of type 3 pneumococcus suspension into their middle ear cavities. The thickness of the RWM increased in various stages of the pneumococcus-evoked otitis media, compared with that of the normal. The thickening was most pronounced on day 1, being about 4 to 5 times greater than that of the normal RWM. All layers of the RWM were affected by the pneumococcal infection, but the major changes were confined to the subepithelial space close to the basement membrane (BM). Together with alterations to the BM, the most distinct pathological features were characterized by an increase and hypertrophy of fibroblasts in association with abundant collagen fibers. Elastic fibers observed close to the inner mesothelial layer under a high power magnification also increased during the experiment. These results will be relevant to a better understanding of the histologic implication of RWM in stages of acute otitis media involving pneumococcus-evoked otitis media.
Animals ; Disease Models, Animal ; Disease Progression ; Ear, Middle/pathology/*ultrastructure ; Male ; Otitis Media/*pathology ; Pneumococcal Infections/*pathology ; Rats ; Rats, Sprague-Dawley ; Streptococcus pneumoniae ; Time Factors