Abstract
AbstractObjectiveThis study aimed to determine anatomical landmarks for accurate and safe middle turn cochleostomy on cadaveric temporal bones.MethodsIn 17 cadaveric wet adult temporal bones, cortical mastoidectomy was performed, followed by extended posterior tympanotomy through which a middle turn opening was created anterior to the stapes footplate. Micro-measurements of various lengths were taken from the cochleostomy to normal middle-ear anatomical landmarks using a digital microscope.ResultsThe mean length from the middle turn cochleostomy to the processus cochleariformis was 1.8 ± 0.3 mm and to the tympanic segment of the facial nerve was 2.2 ± 0.3 mm. The mean shortest length from the oval window to the osseous spiral lamina was 2.4 ± 0.3 mm and to the internal carotid artery was 5.0 ± 0.6 mm. The mean shortest length from the round window to the internal carotid artery was 4.3 ± 0.6 mm.ConclusionA middle turn cochleostomy can be safely drilled by using the measured lengths in difficult cases.
Funder
Christian Medical College, Vellore
Publisher
Cambridge University Press (CUP)
Subject
Otorhinolaryngology,General Medicine