The Canterbury technique for canalplasty via an endaural approach in the surgical management of chronic refractory otitis externa

Assessment and management of chronic otitis externa

PURPOSE OF REVIEW

Chronic otitis externa (COE) remains a frustrating problem for both patient and physician. The end stage of disease, medial fibrosing otitis externa, is very challenging to repair. New and old therapies and promising approaches to the treatment of this often recalcitrant problem are presented in this review.

RECENT FINDINGS

Tacrolimus, a nonsteroidal immunosuppressant, and fluocinolone acetonide oil 0.01%, a medium-high potency steroid preparation, may offer additional therapeutic options in the struggle against this inflammatory ear canal/skin condition of often unknown cause. Relative potencies of many steroid preparations will be presented along with several treatment strategies for controlling COE. Underlying autoimmune problems such as Sjögren's disease, sarcoidosis, and amyloidosis must be searched and, if present, addressed and treated for resolution of symptoms. Cutting edge therapies, including use of bacteriophages and inflammatory proteases, will also be reviewed.

SUMMARY

No single therapy will be successful for every patient with COE. The search for an underlying cause, the removal of all possible irritants to the ear canal skin (e.g. Q-tips, water), debridement, and both topical and occasionally, systemic therapy will control (not cure …) the disease process in the vast majority of patients.

Outcomes of canalplasty for chronic obliterative otitis externa

Introduction:

Chronic obliterative otitis externa is a rare cause of conductive hearing loss, characterised by stenosis of the deep ear canal secondary to chronic inflammation. A multitude of canalplasty techniques have been described, with variable success.

Method:

Fourteen patients undergoing canalplasty performed by the senior author for refractory obliterative otitis externa, over an 8-year period, were included in the study. All underwent split-skin grafting of the denuded canal and meticulous post-operative aural care. Outcome measures included the Glasgow Benefit Inventory and pure tone audiology.

Results:

At 3 months post-operatively, the four-tone average threshold had improved by a mean of 13.9 dB (95 per cent confidence interval –9.9 to 37.8 dB; t < 0.001) in the operated ear. The mean Glasgow Benefit Inventory score was 20 (95 per cent confidence interval −2.3 to 42.1).

Conclusion:

Significant improvements in both hearing and quality of life are achievable in patients with end-stage obliterative otitis externa treated surgically. Highly trained and competent aural care practitioners are a prerequisite for the success of the procedure, and a substantial number of patients must be prepared to submit to long-term follow-up care.

Canal wall cholesteatoma following canalplasty

INTRODUCTION

Bony canalplasty is a common otological procedure performed to widen a narrow ear canal. The aim of this report is to describe two unusual patients who presented with a canal wall cholesteatoma many years after bony canalplasty.

CASES

Two patients, aged 28 and 52 years, are presented. Both underwent canalplasty, 14 and 17 years before re-presenting with cholesteatoma evident through posterior canal wall defects. Both patients underwent exploration of the mastoid cavities and cartilage reconstruction of the canal walls. There was no recurrence at 24 and three month follow-up examinations (variously), hearing was preserved in both cases, and the patients suffered no early complications.

CONCLUSIONS

The most frequent long-term complication of canalplasty is re-stenosis of the external auditory canal. The importance of sealing any inadvertently opened mastoid air cells, in order to avoid the late complication reported, is emphasised.

Relative humidity of the external auditory canal in normal and abnormal ears, and its pathogenic effect

OBJECTIVE

To find the relative humidity of the normal external ear canal and to demonstrate that the relative humidity of the external auditory canal was higher in abnormal ears, i.e. ears commonly associated with chronic discharge.

SETTING

Secondary health care within the ENT departments of Addenbrooke's and Hinchingbrooke hospitals.

DESIGN

A clinical observational study.

PARTICIPANTS

Volunteers seen in ENT outpatients. Inclusion criteria for the normal ear group, was a normal ear with no history of infection or previous ear disease. Inclusion criteria for abnormal ear group commonly associated with chronic discharge. Exclusion criteria were the presence of pus or infection within the ear canal.

METHOD

The relative humidity of the external ear canal was measured in normal and abnormal ears. Abnormal ears were grouped as those commonly associated with chronic discharge, mastoid cavities, tympanic perforations, recurrent otitis externa and hearing-aided ears.

RESULTS

The range of relative humidity of normal ears is 40-70%. The humidity in abnormal ears was found to be significantly higher than the humidity in normal ears (P < 0.0001).

CONCLUSION

The raised relative humidity in the external canal may explain the predisposition of certain abnormal ears to chronic discharge and infection. If the humidity of the canal could be brought down to a normal level, this could offer a new therapeutic treatment.