Forty children diagnosed as having chronic purulent rhinitis unresponsive to medical and surgical management were studied. After a mean follow-up of six years and nine months the condition resolved spontaneously in 95% of the children, usually after reaching the age of 7 years.
This study was performed to design a method for the culture of rat middle-ear epithelium and to apply the method to investigate the characteristics of this epithelium. Culture of explants of middle-ear epithelium in the presence of the epidermal growth factor was successful, whereas serial cultivation required 3T3 feeder cells in addition to the epidermal growth factor. Cultured middle-ear epithelium was studied by phase-contrast microscopy, transmission and scanning electron microscopy, and combined light and scanning electron microscopy (LM/SEM). These techniques showed similarity between the cultured and the natural middle-ear epithelium. Explants and outgrowths showed both flat polygonal and ciliated epithelial cells.In serial cultivation, however, only the first of these cell types was observed. Frequently, a single primary cilium was found on the cell surface. Transmission electron microscopy showed cross-linked envelopes whose formation was promoted by ionophore X537A. Cytokeratin was demonstrated by immunoblotting, immunofluorescence, and immunoperoxidase methods, using an anti-cytokeratin monoclonal antibody. The model described here permits study of the differentiation of middle-ear epithelium in vitro and may be of future value for the study of chronic middle-ear diseases.
The behavior of a ceramic, sintered hydroxylapatite in animal experiments and clinical trials is reported. This material demonstrates its usefulness in the reconstruction of bony defects in the external ear canal and as replacement of the bony ear canal in a total alloplastic middle ear prosthesis.
The results are reported of reconstructions of the middle ear with hydroxylapatite implants performed between 1980 and 1986 with an average follow-up of 5 years. The findings concern 120 canal wall prostheses made of hydroxylapatite. It was possible to reconstruct a radical cavity with a new ear canal. The results obtained with ossiculoplasty in 170 patients are reported. In patients lacking an incus, an incus prosthesis made of hydroxylapatite gave air-bone gap closure to within 20 dB in 83.3% of the patients. Extrusion was not observed. In cases with the stapes superstructure and incus both missing, an incus/stapes prosthesis made of hydroxylapatite gave an air-bone gap closure to within 20 dB in 75.7% of the cases, when used as an assembly. Extrusion was not observed. When the prosthesis was used as a columella, the results were less favorable (41.1%), and two prostheses were extruded during the postoperative control period. Recurrent cholesteatoma was not seen in cases in which eradication and reconstruction were staged.
The effect of the extracellular calcium concentration on serially cultured rat middle ear epithelium was investigated with phase contrast microscopy, scanning electron microscopy, and transmission electron microscopy, as well as by a method to induce cornified envelope formation with a calcium ionophore. The results show that calcium concentration affects cell morphology and terminal differentiation. Furthermore, a role in the proliferation rate, secretory activity and migration seems likely. Since the extracellular calcium concentration may fluctuate locally during osteoresorption or osteodeposition, both of which occur during otitis media, this concentration might be an important factor in the pathogenesis of both acute and chronic otitis media.
