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Updated: May 27, 2026

Endoscopic Endonasal Trans-sphenoidal Approach: Minimally Invasive Surgery for Pituitary Adenomas
Published on: January 17, 2018
Petrous apex cholesterol granuloma involving the sphenoid sinus
Dirk Korbmacher1, Martin Lehmann, Hans-Björn Gehl
1Department of Otolaryngology, Head and Neck Surgery, Bielefeld Academic Teaching Hospital, Teutoburger Str. 50, 33604 Bielefeld, Germany.
Abstract:
Petrous apex cholesterol granulomas are slowly expanding lesions that clinically present with a variety of cranial nerve deficits. We present a case of a 40-year-old man with a right-sided, sudden-onset hearing loss. Apart from a 60-dB high-frequency sensorineural hearing loss in the right ear, all other neurotologic examinations were normal. Computed tomography revealed partial destruction of the right carotid canal, petrous apex, and clivus. Surgical treatment was performed via an endoscopic transnasal, trans-sphenoid approach using an image-guidance system. Postoperative magnetic resonance imaging showed a significant reduction in the size of the cholesterol granuloma and a stable hearing threshold.
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