Temporal bone histopathology case of the month: Idiopathic external ear canal cholesteatoma

Taste Alteration in External Auditory Canal Cholesteatoma: Indicator of Impending N VII Affection

INTRODUCTION

External auditory canal cholesteatoma (EACC) is a rare disease, with an estimated incidence of approximately 1:1,000 adult and 1.6:1,000 pediatric otologic patients. Systematic studies of chronic ear disease and taste alteration prior to surgery are rare; in fact, there are no such studies for EACCs. Therefore, we describe chorda tympani nerve (CTN) dysfunction and the related clinical consequences in EACC patients.

METHODS/STUDY DESIGN

Between 1992 and 2021, we retrospectively analyzed the symptoms, signs, and radiological and intraoperative descriptions of CTN involvement in 73 patients. Liquid taste tests and, since 2009, Taste StripsTM as well as an olfactory screening test (Smell DiskettesTM) have been performed for all symptomatic patients and, when feasible, all other EACC patients.

LEVEL OF EVIDENCE: 4

RESULTS

Ten of 73 patients complained subjectively of dysfunction, and 8 showed abnormal taste test results. Four patients complained of olfactory dysfunction (3 cases with pathological taste tests). Gustatory dysfunction was most frequent in radiogenic EACC cases (n = 4), followed by postoperative EACC (n = 3). Two postoperative patients were asymptomatic despite abnormal test results. Rarely, patients with idiopathic (n = 2) and posttraumatic (n = 1) EACC showed acute taste dysfunction that was confirmed in each with abnormal test results.

DISCUSSION/CONCLUSION

CTN dysfunction often developed asymptomatically in chronic ears, except for idiopathic and posttraumatic EACCs under previous healthy middle ear conditions. Taste disturbance is not a cardinal symptom of EACC, but objective testing suggests that up to one out of 10 EACC patients with advanced disease may experience regional gustatory dysfunction prior to surgery. Especially in context of a new and acute presentation, regional taste dysfunction may alert the clinician of potential progressive EACC invasion and danger to the facial nerve.

Endoscopic Ear Surgery for External Auditory Canal Cholesteatoma

BACKGROUND

Treatment of external auditory canal cholesteatoma (EACC) has been a question of debate. To our knowledge and according to a systematic review of endoscopic ear surgery (EES) in 2015, this study describes for the first time the technique and outcome by solely transcanal EES for EACC.

STUDY METHOD

Retrospective case series, level of evidence IV.

METHODS

Between October 2014 and December 2016, nine patients with unilateral EACC have been treated by EES. Using a bimanual technique, canaloplasty has been performed using tragal perichondrium, cartilage, or artificial bone. Symptoms, signs, and reconstruction technique have been assessed and the primary endpoint: healing time was compared with benchmark values in the literature.

RESULTS

During the 26 months study period all of our nine Naim stage III EACCs were successfully treated by EES with median healing time of 23.8 days. EACC limited to the external auditory canal (Naim stage III) represented an ideal target for EES minimizing tissue damage and thus median healing time compared with retroauricular (42-56 d) or endaural (59 d) surgical techniques.

DISCUSSION

Shorter healing time helped to reduce skepticism toward a surgical treatment of EACC from the patient's perspective. Moreover, EES relied on reduced bulky equipment, dressing time, and complex maintenance compared with microscopic techniques.

CONCLUSION

Transcanal endoscopic surgery is a valid treatment option for EACC up to Naim stage III. Moreover, the described procedure fosters in our eyes the teaching of our residence to get familiar with the basic steps of EES.

Clinical characteristics of spontaneous cholesteatoma of the external auditory canal in children comparing with cholesteatoma in adults

The purpose of this study was to investigate the characteristics of external auditory canal cholesteatoma (EACC) in children through evaluation of the clinical and radiologic features as well as treatment outcomes. The clinical records were retrospectively reviewed for children under 15 years of age diagnosed with spontaneous EACC between March 2004 and December 2011. The clinical data of adults diagnosed with spontaneous EACC during the same period were evaluated to compare with EACC in children. Eight patients (3 males and 5 females) with pediatric EACC and 18 patients (7 males and 11 females, 20 ears) with adult EACC were included within the boundary of the study. The mean ages were 12.4 years (age range 9-15) for pediatric EACC and 49.8 years (age range 29-79) for adult EACC patients. Follow-up periods ranged from 8 to 86 months (mean 32.5 ± 8.62) in pediatric EACC and from 6 to 72 months (mean 22.2 ± 5.36) in adult EACC. Pediatric EACC, showed involvement most commonly in the posterior wall, while the inferior wall was most commonly involved in adult EACC. Pediatric EACC tended to show a more focal involvement and was not as extensive as adult EACC. Extension into the adjacent structures was similar in both groups, but bony destruction was more common in the adult group. Two children and eight adult patients were treated with surgery, but four adult cases needed more extensive surgical treatment because their disease was widely spread to included areas such as the mastoid segment of facial nerve and the temporomandibular joint. Six pediatric cases treated with conservative management showed no progression of disease on physical examination at the last visit, but two cases of adults progressed and required canaloplasty. Pediatric EACC shows less aggressive behavior compared to adult EACC. Adequate management may work better in pediatric than in adult EACC, even though the treatment modality is conservative management.