Management of Petrous Apex Lesions

Abstract

\s=b\Advancements in imaging pose new diagnostic and therapeutic dilemmas as smaller lesions in the relatively inaccessible regions of the petrous apex and clivus are identified. Differentiation of true pathology from artifact and anatomic variants is critical in management of these lesions. We describe our experience with five patients diagnosed with petrous apex lesions: three, cholesteatomas; one, cholesterol granuloma; and one, false-positive. Soft-tissue obliteration of the temporal bone defect with postoperative followup using high-resolution computed tomographic scanning and magnetic resonance imaging is proposed as an alternative to exteriorization.

Bilateral Cholesterol Granulomas

“…Care must be taken not to confuse the hyperintensity of bone marrow of the petrous apex on T1-weighted imaging with disease. Comparison with the contralateral petrous apex and assessment of pneumatization with the CT scan can differentiate the normal variant anatomy from true disease (12).…”

Cerebellar Abscess Secondary to Cholesteatomatous Otomastoiditis—An Old Enemy in New Times

“…Regarding the closure of the defect between the mastoid and the posterior fossa or middle fossa, this can be achieved with bone plates [68,69], bone chips [70], muscle [71,72], or fat [73]. Among these materials, bony material is harder to resorb than soft tissue [73].…”

Cholesterol Granuloma of the Petrous Apex

“…Primary petrous apex lesions are those that arise from the central petrous apex or the anatomic boundaries of the region, and account for approximately 40% of petrous apex lesions. [1][2][3][4][5][6] Secondary lesions impinge on the petrous apex from an outside source, which may derive from invasion from a bordering region or from a metastatic lesion; secondary lesions account for the remaining 60% of petrous apex lesions.…”

“…Primary lesions account for approximately 40% of petrous apex lesions. [1][2][3][4][5][6] PATHOPHYSIOLOGY OF CHOLESTEROL GRANULOMA Cholesterol granuloma of the petrous apex forms as a result of foreign-body giant-cell reaction to cholesterol crystals. The poor ventilation, interference with drainage, and hemorrhage in a usually pneumatized space are predisposing factors leading to the formation of the cyst.…”