Keratosis obturans is a condition of the external auditory canal (EAC) characterised by formation and accumulation of desquamated keratin resulting in varying symptoms. Clinically presents as otalgia, conductive hearing loss and recurrent infection. Typically seen in younger age group and can occur bilaterally. Extension to adjacent structures can occur and result in further complications. The proposed theory is that there is a defect in epithelial in migration resulting in widening / osteitis of external canal bone.
Condition was first described by Toynbee in 1850, and named by Wreden in 1874. Pipergerdes in 1980 distinguished keratosis obturans as separate disease from external auditory canal cholesteatoma. Ever since various treatment regime has been recommended but none of them have been curative. Michael M Paparella was first to propose surgical treatment in 1966 and he then modified the surgical technique in 1981.
Because the defect is in epithelial migration, canaloplasty with or without graft, without obliterating the bony canal defect will not restore epithelial migration. Hence, M. M Paparella’s surgical technique was NOT popularized.
Mr Basavaraj proposes novel technique which not only clears the diseased bone but obliterates the bony defect, and grafts the ear canal to bring it back to normal shape and size to encourage normal epithelial migration.
Bony canaloplasty is a surgical technique performed by Mr Basavaraj. It is performed by making endo-meatal incision at the lateral border of the keratosis obturans lesion. Then, post-auricular incision is made at the bony-cartilage junction. Harvest good amount of conchal cartilage and temporalis fascia graft. Post-auricular and ear canal incisions are merged – retract pinna forward (with a ribbon gauze). Elevate the skin from the canal (9 o’clock – 3 o’clock) inferiorly (in large defect closer to tympanic membrane – elevate the tympanic membrane with tympano-meatal flap). Drill out infected and irritable bone with cutting bur until healthy bone is exposed. Fill the defect with conchal cartilage (either one or two layers). Use the temporalis fascia over the cartilage or underlay if tympano-meatal flap is done. Fill the ear canal with gel foam and BIPP. Close the post-auricular incision in two layers using 4-0 vicryl and proline. The sutures should be removed in 7 days, and the pack in 3-4 weeks. The patient should have a second review after 12 weeks post-surgery. If canal is re-epithelialized patient can be discharged, if not another follow-up 6 months from surgery.
Previous radiotherapy to temporal bone
Day case, theatre setting
Anaesthesia, preferably GA But, can be done under LA,
external auditory canal, temporal bone
one off surgical procedure prevents recurrent problems and recurrent visits to ENT outpatients for regular dewaxing
Sarah Harrison, Librarian at St Mary's Hospital
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Park, So Young; Jung, Young Hoon; Oh, Jeong-Hoon., Clinical characteristics of keratosis obturans and external auditory canal cholesteatoma. Otolaryngology-Head & Neck Surgery; vol. 152 (no. 2); p. 326-330; Feb 2015