Variations of Bone Conduction Hearing in Chronic Suppurative Otitis Media after Tympanoplasty / 听力学及言语疾病杂志

ABSTRACT

Objective The purpose of this paper is to study the variations of the bone conduction hearing in the patients with chronic suppurative otitis media complicated by bone conduction deterioration after tympanoplasty and to analyze the relative factors. Methods In 54 cases (61 ears) of decreased bone conduction thresholds associat-ed with chronic suppurative otitis media, reviewed retrospectively were the data before the operation and during the follow-ups from 3 to 27 months. The bone conduction thresholds at 0. 5,1, 2 and 4 kHz were studied in relation to the courses of disease, the complications of cholesteatoma, the operation procedures and the reconstructions of os-sicular chains before and after surgeries. Results Before operation the most obvious hearing loss of bone conduction was found at 4 kHz in 61 ears, while after operation the average bone conduction hearing at the 4 frequencies was improved at different degrees with the most at 2 k Hz. Thirty-two of 61 cases (52.50%) were found to have their hearing improved at least by more than 10 dE at two frequencies without any deterioration at the 4 frequencies. Con-clusion The factors of the duration of disease and complications of cholesteatoma are obviously not related to the improvement of hearing after operation. A patient with reconstruction of ossicular chain is markedly superior to one without the reconstruction in improvement of hearing. When the auditory ossicular chains and functions of the oval and/or round windows are damaged, the bone conduction hearing can be affected accordingly. However the hearing of some cases will be improved after tympanoplasty. Also, the possible improvement is also related to different sur-geries in treating patients with middle ear infections.