Anatomic variability of oval window as pertaining to stapes surgery

Abstract

Purpose: The purpose of the study is to study the details of dimensions and shape of oval window in different age groups, sides and genders and their clinical implications. The oval window is a key structure while performing surgeries in relation to stapes. An intricate knowledge of the shape and size of the oval window is important for the reconstruction and fitting of cartilage compatible with the native shape of the oval window.

Methods: Sixty normal wet cadaveric temporal bones of known age; gender and side were micro-dissected. The maximum height and width of the oval window was measured. The shape of the oval window was noticed.

Results: The mean value for maximum height and width of the oval window was 1.31 ± 0.28 mm and 2.67 ± 0.42 mm, respectively. The height and width of the oval window ranged between 1 mm and 1.5 mm and 2 mm and 3 mm in majority of the cases. he oval window was found to be oval shaped in 53.3% cases, other shapes such as kidney, D shape, rectangular or trapezoidal were also observed.

Conclusions: The refined morphometric information of the oval window will help in preoperative assessment and surgical planning of various oval window-related surgical procedures. The knowledge may also help in designing and selecting proper cartilage shoe for the best outcome. Narrow oval window may cause procedural complications and surgeon discomfort in various stapes surgeries.

Keywords: Oval window; Stapedotomy; Stapes; Temporal bone.