الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 88 |  |  |
| | | from | 88 | | |
Abstract
The round window is one of the two openings into the cochlea from the middle ear. The other opening is the oval window. The round window is covered by the round window membrane which vibrateswith an opposite phase to acoustic vibrations entering the cochleathrough the stapes at the oval window.The round window is considered very important as it participates in several physiological aspects of ear functionsincluding auditory function, a gateway for local therapy of inner ear and as a portal for electrode insertion during cochlear implantation.The transcanal approach in comparison to posterior tympanotomy has many advantages. It gives better exposure of round window. It is simple and less risky to facial nerve and chordatympani. Furthermore, it is suitable for patients with unfavorable mastoidor facial recess anatomy.