Endoscopic Versus Microscopic Stapedectomy For Treatment of Otosclerosis

Objective:The aim of this study to compare the outcome of endoscopic with that of microscopic stapedectomy.
Methods:This comparative study involved a prospective analysis of patients with conductive hearing loss who underwent stapedectomy at the department of Otorhinolayngology, Assiut University hospital between July 2015 and October 2017. The patients were divided into two groups: Patients in group I were operated with endoscope and patients in group II were operated with microscope. Pure tone audiometry was carried out in all patients preoperatively and postoperatively. Air and bone conduction thresholds were measured at frequencies of 500, 1000, 2000 and 4000 HZ and the median and interquartile range (IQ) of the pre and postoperative air-bone gap were noted. Extent of bone work at the posterosuperior part of the external auditory canal, accessibility to the oval window and manipulation of the chorda tympani nerve, postoperative complications and hearing results were also noted and compared between the two groups.
Results:The median preoperative air-bone gap was 35.8 dB (30.4-45.03) in group I (endoscopic) and 35.85 dB (32.1-43.38) in group II (microscopic) whereas the median postoperative air-bone gap was 16.7 dB (5-39.58) in group I and 15.85 dB (10 -19.58) in group II. There was no statistical difference for hearing results between both groups. The need for bone work and manipulation of the chorda tympani nerve for better visualization was more in microscopic group than the endoscopic group and the difference between both groups was statistically significant. The incidence of complications in both groups was nearly the same in both groups and the difference between them was statistically insignificant.
Conclusion: Endoscopic stapedectomy has many advantages over microscopic stapedectomy as better visualization, and easy accessibility to the stapes, oval window niche, and facial nerve. Drilling of the posterosuperior part of the external auditory canal or removal of the scutum and manipulation of the chorda tympani nerve are less frequent with the endoscopic technique