Petrous bone extension of middle-ear acquired cholesteatoma

Role of High Resolution Computed Tomography of Mastoids in Planning Surgery for Chronic Suppurative Otitis Media

Chronic suppurative otitis media (CSOM) presents with a typical history of recurrent otorrhoea with tympanic membrane perforation. The diagnosis of cholesteatoma is usually made on otologic examination. High resolution computed tomography (HRCT) is indicated to evaluate the extension and the complications of cholesteatoma. The aim of the work was to study the role of HRCT in detecting, evaluating diagnosing and managing CSOM. All patients presenting with CSOM who were planned for mastoid exploration surgery in department of ENT, Gauhati Medical College and Hospital within a period of 2 years-from 1st January, 2013 to 31th December, 2014, were taken up for the study. HRCT mastoids done routinely before cholesteatoma surgery, but with improved resolution, to characterize all middle ear structures and complications of the disease prior to surgery, might guide as road map during mastoid explorations for unsafe CSOM. The important role of HRCT lies on the early detection of cholesteatoma, and more conservative surgical procedures can be used to eradicate the disease.

Middle ear cholesteatoma: characteristic CT findings in 64 patients

BACKGROUND

High resolution computerized tomography (HRCT) is valuable for detection of early erosive changes suggestive of cholesteatoma. The aim of our study was to determine characteristic CT findings in patients with middle ear cholesteatoma.

METHODS

We conducted a retrospective review of CT scans and surgical and histopathological reports in 64 patients with middle ear cholesteatoma (35 male, 29 female; age range, 7-80 years, median age, 22 years). CT scans were evaluated for the presence of intra-tympanic non-dependent soft tissue density, the extent of middle ear involvement, bone expansion and thinning, and bone erosions involving the ossicles and adjacent structures.

RESULTS

Middle ear cholesteatoma was more common in male patients and in patients aged 20-35 years. All patients had soft tissue density in the middle ear. Fifty-nine (92%) had expansion of the aditus and mastoid antrum, 59 (92%) had erosions of the ossicles, with involvement of the long process of the incus in 48 (75%), 55 (86%) had an eroded scutum, 55 (86%) an eroded facial nerve canal, 57 (89%) an eroded Koerner's septum, which was totally destroyed in 19 (27%), 48 (75%) had tegmen erosion, and 63 (98%) had erosions of the antral walls. The correlation of pre-operative CT with surgical and histopathological findings was 97%.

CONCLUSION

Middle ear cholesteatoma is a distinct clinical entity with characteristic findings that may be suggested by CT imaging. These findings should alert the clinician to the possibility of cholesteatoma, which will guide in the surgical approach and treatment plan.