Presented at the North American Skull Base Society Meeting, Las Vegas, Nevada, U.S.A, February 17–19, 2012.
Version of Record online: 12 FEB 2013
Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.
Volume 123, Issue 3, pages 581–583, March 2013
How to Cite
Shoman, N., Donaldson, A. M., Ksiazek, J., Pensak, M. L. and Zimmer, L. A. (2013), First stage in predicative measure for transnasal transsphenoidal approach to petrous apex cholesterol granuloma. The Laryngoscope, 123: 581–583. doi: 10.1002/lary.23754
The authors have no funding, financial relationships, or conflicts of interest to disclose.
- Issue online: 26 FEB 2013
- Version of Record online: 12 FEB 2013
- Manuscript Accepted: 23 AUG 2012
- Manuscript Revised: 10 AUG 2012
- Manuscript Received: 23 MAY 2012
- Cholesterol granuloma;
- petrous apex;
- computer tomography;
- petrous angle;
This study evaluates the feasibility of the transsphenoidal approach to petrous apex cholesterol granuloma based on the petrous angle. This is the angle centered at the vomer, extending between the medial aspect of the C3 segment of the internal carotid artery and the occipital protuberance. The aim of this study is to determine the average petrous angle in a population of normal computed tomography scans.
Retrospective review at the University of Cincinnati Medical Center.
Two of the authors independently reviewed 400 consecutive normal temporal bone computed tomography scans obtained between September and December of 2009. All scans had slice thickness of 1.25 mm at 0.6-mm intervals. Axial images parallel to the orbitomeatal plane were analyzed, and the petrous angle was measured bilaterally. Interrater reliability was tested on 50 of the computed tomography scans.
A total of 400 temporal bones were reviewed. The mean and median petrous angle was 17.7 and 16.5 degrees, respectively. Eleven (2.8%) had an angle ≤10.0, 331 (82.8%) between 10.1 to 20.0, and 58 (14.5%) ≥ 20.1. The interrater variability was highly correlated (r = 0.912, P < .005).
Normative data on consistent petrous apex radiographic landmarks are important for assessing the feasibility of the transphenoidal approach to the petrous apex for cholesterol granuloma drainage. Based on a large population of normal computed tomography scans, the majority of temporal bones (82.8%) have a petrous angle ranging between 10.0 and 20.0 degrees. Laryngoscope, 2013