Acute Effects of Irradiation on Middle Ear Mucosa

Abstract

Single field, fixed irradiation of bilateral tympanic cavities using 200-kV x-rays was administered to five guinea pigs. The irradiation dose was 30 Gy. They were killed immediately after irradiation, and bilateral middle ear mucosa was examined for ciliary activity and epithelial structure. Significant deterioration of the ciliary activity in the middle ear mucosa was observed, proximal as well as distal to the eustachian tube. Electron microscopy showed various changes in the irradiated middle ear mucosa. The most conspicuous findings were hyperreactivity in secretion, vacuolation of ciliated cells, and stomal edema.

Irradiated ears in nasopharyngeal carcinoma survivors: A review

“…Unlike OME in preirradiated NPC patients, postirradiated OME is due to both organic obstruction and functional impairment of the tube . The former is caused by radiation injury to the peritubal region, especially at radiation dosages up to 80 Gy, and functional impairment is caused by inflammatory process within the radiation field due to radiation‐induced tissue reaction (i.e., mucositis, desquamation, or edema) and tissue damage (i.e., atrophy, fibrosis, degeneration, or necrosis) in the radiation‐exposed area . Nevertheless, inflammatory reaction may be reversible by halting ongoing destructive processes.…”

Nasal Cytological Changes as Late Effects of Radiotherapy for Nasopharyngeal Cancer

“…Previous studies involving the middle ear mucosa reported that irradiation induces acute effects, including vacuolization of ciliated cells, appearance of compound cilia, expansion of intercellular spaces, hyperreactivity of secretion, and stromal edema. [17][18][19] Delayed effects at 6-11 months after irradiation included reduction of cytoplasmic mass, variable degrees of ciliary loss, and widened intercellular spaces. 20 Mucosa is composed of rapidly renewing, proliferating cells, whereas soft tissues, particularly their vasculoconnective components, are more slowly renewing structures.…”

Radiation-Induced Hearing Impairment in Patients Treated for Malignant Parotid Tumor

“…This could be partially explained by serous effusion in the middle ear and disturbance of ventilation and drainage caused by edema of the mucous membrane, which leads to obstruction of the eustachian tube. 14 In an animal study, Ohashi et al 15 noted serous effusions in the tympanic cavities of guinea pigs irradiated with a single dose of 30 Gy. They also noted degeneration of cilia or ciliated cells and capillary injury with increased permeability.…”