N Sanghan1, T Chansakul1, E D Kozin1, A F Juliano1, H D Curtin1, K L Reinshagen2. 1. From the Department of Radiology (N.S.), Prince of Songkla University, Hadyai, Songkhla, Thailand. 2. From the Department of Radiology (N.S.), Prince of Songkla University, Hadyai, Songkhla, Thailand katherine_reinshagen@meei.harvard.edu.
Abstract
BACKGROUND AND PURPOSE: Otosclerosis is commonly identified on CT as a focus of hypodensity in the otic capsule anterior to the oval window. However, otosclerosis can have a sclerotic phase approximating the density of normal bone, making diagnosis challenging. This study assesses differences in otic capsule contour and thickness anterolateral to the anterior margin of the oval window in patients with otosclerosis compared with individuals with normal hearing. MATERIALS AND METHODS: Axial CT of 104 ears with clinically diagnosed otosclerosis and 108 consecutive ears of audiometrically normal individuals were retrospectively reviewed. Two radiologists independently evaluated the pattern of otosclerosis, otic capsule contour, and bone thickness on standardized axial images at the level of the oval window and cochleariform process. Measurements were made from the posterolateral margin of the cochlea to the apex of the otic capsule convex contour just anterolateral to the anterior margin of the oval window. In the absence of a convex contour, the sulcus between the oval window and the cochleariform process was identified, and measurement to the depth of the sulcus was used. Receiver operating characteristic analysis determined the best cutoff value of otic capsule thickness. RESULTS: Mean otic capsule thickness (2 SDs) was 3.08 (0.93) mm and 1.82 (0.31) mm in patients with otosclerosis and individuals with normal hearing, respectively (P < .001), with excellent interobserver agreement. Otic capsule thickness of >2.3 mm had 96.2% sensitivity, 100% specificity, 100% positive predictive value, and 96.4% negative predictive value for otosclerosis. A bulging/convex contour of the otic capsule had 68.3% sensitivity, 98.1% specificity, 97.3% positive predictive value, and 76.3% negative predictive value. CONCLUSIONS: Patients with otosclerosis have significantly thicker bone abutting the oval window than individuals with normal hearing.
BACKGROUND AND PURPOSE:Otosclerosis is commonly identified on CT as a focus of hypodensity in the otic capsule anterior to the oval window. However, otosclerosis can have a sclerotic phase approximating the density of normal bone, making diagnosis challenging. This study assesses differences in otic capsule contour and thickness anterolateral to the anterior margin of the oval window in patients with otosclerosis compared with individuals with normal hearing. MATERIALS AND METHODS: Axial CT of 104 ears with clinically diagnosed otosclerosis and 108 consecutive ears of audiometrically normal individuals were retrospectively reviewed. Two radiologists independently evaluated the pattern of otosclerosis, otic capsule contour, and bone thickness on standardized axial images at the level of the oval window and cochleariform process. Measurements were made from the posterolateral margin of the cochlea to the apex of the otic capsule convex contour just anterolateral to the anterior margin of the oval window. In the absence of a convex contour, the sulcus between the oval window and the cochleariform process was identified, and measurement to the depth of the sulcus was used. Receiver operating characteristic analysis determined the best cutoff value of otic capsule thickness. RESULTS: Mean otic capsule thickness (2 SDs) was 3.08 (0.93) mm and 1.82 (0.31) mm in patients with otosclerosis and individuals with normal hearing, respectively (P < .001), with excellent interobserver agreement. Otic capsule thickness of >2.3 mm had 96.2% sensitivity, 100% specificity, 100% positive predictive value, and 96.4% negative predictive value for otosclerosis. A bulging/convex contour of the otic capsule had 68.3% sensitivity, 98.1% specificity, 97.3% positive predictive value, and 76.3% negative predictive value. CONCLUSIONS:Patients with otosclerosis have significantly thicker bone abutting the oval window than individuals with normal hearing.
Authors: Péter Révész; Balázs Liktor; Bálint Liktor; István Sziklai; Imre Gerlinger; Tamás Karosi Journal: Eur Arch Otorhinolaryngol Date: 2015-01-06 Impact factor: 2.503
Authors: Balázs Liktor; Péter Révész; Péter Csomor; Imre Gerlinger; István Sziklai; Tamás Karosi Journal: Eur Arch Otorhinolaryngol Date: 2013-09-19 Impact factor: 2.503
Authors: Johanna Pekkola; Anne Pitkaranta; Alexandra Jappel; Christian Czerny; Wolf-Dieter Baumgartner; Markku Heliovaara; Soraya Robinson Journal: Radiology Date: 2003-11-14 Impact factor: 11.105
Authors: Alicia M Quesnel; Reuven Ishai; Timothy Meehan; Jennifer T O'Malley; Renee Mitchell; Jennifer J Shin; Hugh D Curtin; Joseph B Nadol; Michael J McKenna; Amy F Juliano Journal: Otol Neurotol Date: 2022-07-01 Impact factor: 2.619