Keratosis obturans

Case contributed by Dr Dalia Ibrahim

Presentation

Right conductive hearing loss. Clinical otoscopic examination revealed a right aural polyp.

Patient Data

Age: 50 years
Gender: Male
CT

Right external auditory canal intraluminal soft tissue density extending laterally from tympanic membrane. Absence of underlying bony changes. The middle ear, including the ossicular chain, is not involved.

Left external auditory canal small soft tissue density showing internal air loculi, representing external auditory canal debris.

Air-fluid level in inferior right mastoid air cell.

Oval lesion fills right part of sphenoid sinus, with bowing of sphenoid sinus septum to left - possibly mucocele.

Case Discussion

Pathology revealed keratosis obturans.

Gross:

1 - soft tissue polyp in external auditory canal: Membranous tissue pieces, 1x1cm, totally submitted.

2 - granulation tissue in external audtory part of external auditory canal: very tiny tissue portion.

MICROSCOPIC:

Examination of the specimen (1) received fragments of cyst wall lined by keratinized squamous epithelium and filled with keratin,specimen (2) revealed tiny fibrous stripe with minimal inflammatory cell infiltration.

No specific granuloma or atypia in sections examined.

Keratosis obturans is a rare external auditory canal (EAC) disease characterized by abnormal accumulation of desquamated keratin and consequently occlusion and expansion of the bony portion of the EAC.

Differential diagnosis

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.