Multidetector Computed Tomography Findings of Auto-Evacuated Secondary Acquired Cholesteatoma: A Morphologic and Quantitative Analysis.

OBJECTIVES: To describe and quantify computed tomography (CT) findings of auto-evacuated (spontaneously drained) secondary acquired cholesteatoma (SAC).

MATERIALS AND METHODS: This multicenter retrospective study included 69 patients with intermittent ear discharge diagnosed with SAC by autoscopy or automicroscopy who were surgically treated. Three independent radiologists measured the medial and lateral attic distance on coronal and axial planes using multidetector computed tomography (MDCT) in 75 ear CTs from 69 patients with intraoperatively verified diagnoses of pars flaccida cholesteatoma (n=36), pars tensa cholesteatoma (n=24), and auto-atticotomy or automastoidectomy (n=15) and compared them with contralateral healthy ears.

RESULTS: A circular or elliptical air-filled cavity surrounded by granulation tissue was morphologically detected on MDCT in these patients. The lateral attic distance was significantly higher in pars flaccida cholesteatoma cases than in contralateral healthy ears on both coronal and axial planes (p<0.05). The medial attic distance was significantly higher in pars tensa cholesteatoma cases than in contralateral healthy ears in the axial pane, but with no difference in the coronal plane.

CONCLUSION: In patients with chronic intermittent aural discharge, nonopacified areas surrounded by granulation tissue, which expands the medial or lateral attic in a CT scan, suggest an auto-evacuated cholesteatoma.