Risk factors for occurrence and progression of external auditory canal cholesteatoma

OBJECTIVE

External auditory canal cholesteatoma (EACC) is characterized by retained squamous debris within the external canal and variable amounts of localized bone destruction. The etiology of primary EACC remains incompletely understood. This study was conducted to analyze the clinical features and backgrounds of patients with primary EACC and to clarify the risk factors for the occurrence and progression of EACC.

METHODS

Sixty-nine ears of 62 patients diagnosed with primary EACC were included in this study (EACC group). Additionally, 74 ears of 60 patients with chronic otitis media (COM) with perforation who underwent tympanoplasty or myringoplasty were included as controls (COM group). We retrospectively investigated the clinical features, life history, and medical history of the patients in both groups. In addition, to investigate the risk factors for progression of EACC, we compared the clinical features and medical history of patients with stage IV (advanced) disease versus stage I + II (mild) disease.

RESULTS

The inferior wall of the bony canal was the main structure affected in patients with primary EACC of all stages. The following factors were significantly more common in the EACC than COM group: older age, female sex, left-sided disease, osteoporosis, renal dysfunction, anemia, and treatment with bisphosphonates. Among these, the most significant factor associated with EACC was renal dysfunction (odds ratio, 11.4; 95 % confidence interval, 2.32-55.9). The significant factors observed in patients with stage IV disease were younger age, male sex, posterior wall involvement, and otorrhea. Surgical treatment was required for more than half of the patients with stage III and IV EACC.

CONCLUSION

Patients with renal dysfunction are at risk of primary EACC. In particular, younger patients and relatively younger elderly patients with posterior wall involvement have a risk of progression to advanced-stage EACC. Canalplasty should be considered in patients with EACC who have these risk factors to prevent progression to advanced-stage disease.

Acquired Stenosis of the External Ear Canal

Acquired stenosis of the external ear canal (ASEEC) is a relatively uncommon condition. Stenosis or narrowing of the external ear canal (EEC) occurs lateral to the tympanic membrane resulting in a skin lined blind canal. Recurrent otorrhea, and conductive hearing loss are typical clinical features. Although ASEEC can be due to different etiologies, a common pathogenesis, namely an inflammatory cascade, has been implicated. Clinical evaluation, audiogram, and Computed tomography (CT scan) form the mainstay of diagnosis. Surgery is the primary modality for treatment. Restenosis is the most common postsurgical complication.

Congenital Anomalies of the Ear Canal

Congenital anomalies of the external auditory canal (EAC) are classically divided into congenital aural atresia (CAA) and congenital aural stenosis (CAS). CAA can present as an isolated anomaly, unilateral or bilateral, or in the setting of a craniofacial syndrome. Hearing testing (ABR with air and bone conduction thresholds for both ears) early in the perinatal period is important to document hearing thresholds. Hearing status thus informs parent counseling on options for hearing habilitation: Bone conducting technology is a must for children with bilateral CAA to support normal speech and language development. Bone conducting technology should be considered for children with unilateral CAA; benefits are unclear. In select candidates, atresia repair can provide improved hearing with a clean, dry, epithelialized ear canal. First branchial cleft cyst or sinus is rare; high index of suspicion is needed to diagnose along with high-resolution CT. Congenital aural stenosis (CAS) is a rare condition, and hearing testing should be similar to that in children with CAA. Early (age 4-5) CT imaging is recommended in the setting of a canal <2 mm or pinpoint canal to evaluate for trapped skin/ear canal cholesteatoma.

Role of Pre Auricular Flap in Reconstruction of Acquired Meatal Stenosis Via Endaural Approach

Acquired meatal stenosis is a difficult entity to treat with a significant recurrence rate. It is normally approached posteriorly via post aural approach and reconstructed using split thickness skin graft. We are presenting a novel method of surgery for acquired meatal stenosis using a pre auricular flap via endaural approach only. The aim was to evaluate the success rate of using a pre auricular flap in acquired atresia of the external auditory canal using the endaural approach. Twenty patients with acquired atresia of the external auditory canal that was surgically treated were retrospectively studied from July 2012 to July 2018. All cases were done using endaural approach only. During the surgery, the atretic tissue was removed, wide canaloplasty done and the stenotic segment widened. Reconstruction of the external auditory canal was done using a pedicled anteriorly based pre auricular flap rotating it into the external auditory canal to cover the bare bone. Of the 20 patrients there were good results in 18 patients with restenosis occurring only in 2 patients. However, a skin tag developed in 2 other patients which was excsiced as OPD procedure and patient was asymptomatic on further follow ups. In all the 20 cases preauricular flap was used for reconstruction along with use of Split thickness skin graft in 10 cases. All 20 cases were operated via endaural route only. Use of a Preauricular flap in surgical treatment of acquired aural stenosis gives good results with a wide dry cavity as the flap is pedicled with its vascular supply and it can be tailor made according to each case and requirement.

Piezoelectric canalplasty for exostoses and osteoma

OBJECTIVE

To evaluate the safety profile and surgical technique for removal of symptomatic exostoses and osteoma of the external auditory canal with a micro-oscillating piezoelectric device.

METHOD

A chart review was conducted on patients undergoing piezoelectric canalplasty between 2019 and 2021 at tertiary referral hospital. Surgery was performed by two surgeons with varying experience. Bone removal was achieved using both osteotomy and osteoplasty. Postoperative complications, operative time and hearing outcome were evaluated.

RESULTS

The study comprised 16 patients (16 ears). No major complications occurred. The skin of the auditory canal was completely preserved in all patients without injury to the tympanic membrane. Except for one patient with known noise-induced hearing loss, there was no postoperative deterioration of the bone-conduction threshold more than 10 dB HL at any frequency. The difference of the bone-conduction threshold in pure-tone audiometry (average for 0.5, 1, 2 and 4 kHz) three weeks postoperatively had a median of 0.6 dB ± 5.7. One patient complained of temporary new tinnitus. One patient had prolonged wound healing. Mean operative time was comparable with literature data.

CONCLUSION

The atraumatic characteristics of the piezoelectric instrument enable low-risk removal of external auditory canal exostoses and osteoma. Through the combination of precise osteotomy and osteoplasty, this novel instrument has the potential to become established in routine canalplasty.

Prevalence of middle ear malformation and outcomes of tympanoplasty and/or canalplasty in patients with and without congenital external auditory canal stenosis

OBJECTIVE

To compare the prevalence of middle ear malformations between patients with and without congenital external auditory canal stenosis (CEACS) and to investigate the outcomes of tympanoplasty and/or canalplasty in terms of tympanic membrane (TM) size and external auditory canal (EAC) stenosis in patients with middle ear malformation.

METHODS

Twenty-five patients who underwent primary tympanoplasty and/or canalplasty for middle ear malformation at a tertiary academic medical center were retrospectively reviewed. CEACS was defined as an EAC diameter of 4 mm or less. Intraoperative findings, including irregularity of the ossicles, facial nerve, or chorda tympani; size of the TM and EAC on computed tomography; and pre- and postoperative hearing level, were collected.

RESULTS

We included 7 and 18 patients with and without CEACS, respectively. The malleus handle defect, anterior deviation of the chorda tympani, and small TM (≤7 mm) (p-values 0.015, <0.001, and 0.003, respectively; Fisher's exact test) had significantly higher prevalence in patients with CEACS than in those without. The mean postoperative air-bone gap (ABG) in patients with CEACS was not significantly different from that in patients with normal-sized EAC (20.6 dB and 19.5 dB, respectively; p-value, 0.121; Mann-Whitney U test). No difference was observed in mean postoperative ABG between patients with small TM and those with normal-sized TM (19.2 dB and 20.0 dB, respectively; p-value, 0.469; Mann-Whitney U test).

CONCLUSION

Patients with CEACS were more likely to have malleus handle defect, anterior deviation of the chorda tympani, and small TM than those without CEACS. Hearing outcome of patients with CEACS and a malformed malleus and/or incus might be equivalent to that of patients without CEACS following tympanoplasty and/or canalplasty, regardless of the EAC or TM size.

The MO-meatocanalplasty: long-term results in the narrow external auditory canal with recurrent otitis externa or the inability to wear a hearing aid

OBJECTIVE

The MO-meatocanalplasty is the oblique modification of the M-meatoplasty. The MO-meatocanalplasty was designed to address the superior quadrants of the meatus and the bony canal without the need for a retro-auricular incision. This retrospective analysis was performed to evaluate the long-term results of the MO-meatocanalplasty in patients with a narrow external auditory canal (EAC) with recurrent otitis externa or in patients unable to wear a hearing aid.

METHODS

Twenty-two ears in twenty consecutive patients who received a MO-meatocanalplasty for a narrow EAC with recurrent otitis externa or the inability to wear a hearing aid were analysed retrospectively. There were no patients included with any type of previous or planned second stage tympanoplasty procedures. A follow-up period of 3 years was analysed for postoperative recurrent narrowing, the self-cleaning capacity of the EAC, the recurrence of otitis externa, the inability to wear a hearing aid, change in hearing level and for all types of aesthetical complaints.

RESULTS

The MO-meatocanalplasty procedure was effective in 82% (n = 18). Postoperative recurrent narrowing was detected in 9% (n = 2). Insufficient self-cleaning capacity of the EAC was 9.1% (n = 2). The ability to wear a hearing aid was restored in all patients with the need for a hearing aid. No aesthetical complaints were reported.

CONCLUSION

The MO-meatocanalplasty is an effective, safe and aesthetical accepted procedure to address the narrow meatus and external auditory canal. With this procedure, there is no need for a retro-auricular incision in order to create a well aerated, dry and self-cleaning EAC in patients with a narrow EAC with recurrent otitis externa or in patient with the inability to wear a hearing aid.

Morphometric Analysis of the External Auditory Canal by Computed Tomography in Indian Population

Various studies have shown variations in size and shape of different anthropometric measurements of external auditory canal. We conducted an anthropometric study of the three-dimensional anatomy of the osseous external auditory canal (OEAC) using high-resolution computed tomography the temporal bone to identify the variations in subset of Indian population from North India. A retrospective review of high-resolution computed tomography images of the temporal bones of 125 patients (250 external auditory canals) of different ages (mean 28.43 years) acquired from September 2014 to February of 2015 was performed. Using a method, as proposed by Mahboubio et al. (Otol Neurotol 33:715-720, 2012), six defined dimensions of the OEAC in the parasagittal planes were recorded at the level of annulus, midcanal and the outermost point of osseous external auditory canal at bony-cartilaginous junction. The length and shape of the OEAC were also studied and the frequency rate of each was recorded. The most prevalent shape of the OEAC was found to be conical (64%) and the mean osseous external auditory canal length was 9.61 mm. The length of the OEAC was significantly different between ages above and below 12 years while the 6 defined cross sectional dimensions were statistically significant between ages above and below 8 years. The history of chronic suppurative otitis media had a significant bearing on the inferior mid-anteroposterior dimension at the level of bony-cartilaginous junction. There was statistically significant difference in supero-inferior diameter in the posterior half at the level of mid-canal and outer bony-cartilaginous junction between males and females. The comprehensive set of standardized measurements collected in this study provides three-dimensional information on osseous external auditory canal geometry. These measurements and the methodology will contribute to the development of element models of the osseous canal for computational modeling purposes and also provide important measurements for design of in-the-canal hearing aids, specialized earplugs and for defining average sizes for canalplasty procedures, in pre- and postoperative surgical planning and assessment of canal atresia and stenosis in Indian population. No such previous study has been done in North Indian population.

Our Experience of Treating Wide Spectrum of External Ear Canal Atresia of Different Etiologies in Pediatric Patients

External auditory canal atresia (EACA) is a common otologic condition. Etiology can vary from congenital to acquired causes. It causes considerable difficulty to the patient. Bilateral ear canal atresia in children can lead to speech delays due to hearing impairment caused by this condition. Though easily diagnosed it is one of the most difficult conditions to treat. Acquired conditions can affect any age group. Restenosis following treatment is very common. This article focuses on the treatment of EACA due to different etiologies and emphasizes on special points of surgical treatment and follow up. Five cases of external auditory canal atresia was treated between 2014 and 2016. Two of them were congenital cases and three were acquired. One congenital atresia patient had pinna abnormalities in the form of one sided anotia and other side microtia. Another patient of congenital ear canal atresia had congenital cholesteatoma. Acquired atresia was due to osteoma, external trauma and surgical trauma following a condylectomy surgery. All the patients were treated surgically. A wide meatoplasty with split thickness skin graft lining the canal/cavity was done to avoid restenosis. Merocel wicks were used in all cases. Removal of localized granulations on follow up helped keep the canal patent especially in congenital EACA. All patients had significant hearing improvement following surgery. Child with bilateral atresia and pinna anomaly has now achieved normal hearing and speech milestones. She does not use any hearing aid. None of the patients developed restenosis of their reconstructed ear canal. One of the patient developed granulations around the meatoplasty edges which was cauterized using silver nitrate. External auditory canal atresia surgery is a difficult surgery keeping in view the distorted anatomy and the propensity of restenosis of the newly constructed ear canal. Hearing restoration in the operated ear is all the more challenging. Meticulous planning with close discussion with patients and their caregivers regarding multiple surgeries has to be done. Using skin graft, doing a wide meatoplasty, using merocel wicks for ear canal dressing are few important aspects of this surgery which can give satisfactory results in long term.

The Correlation Between Pre and Postoperative Hearing Level with High Resolution Computed Tomography (HRCT) Findings in Congenital Canal Atresia (CAA) Patients

In managing patient with congenital congenital aural atresia (CAA), preoperative high resolution computed tomography (HRCT) scan and hearing assessment are important. A grading system based on HRCT findings was first introduced by Jahrsdoefer in order to select appropriate candidates for operation and to predict the postoperative hearing outcome in CAA patients. The score of eight and more was considered as a good prognostic factor for hearing reconstruction surgery. However previously in our center this score was not used as the criteria for surgical procedure. This study was conducted at Center A to evaluate the correlation between pre and postoperative hearing level with HRCT based on a Jahrsdoefer grading system in patients with CAA. All records and HRCT films with CAA from January 1997 until December 2007 at Center A were evaluated. The demographic data, operative records, pre and post operative hearing levels and HRCT findings were analyzed. Hearing level in this study was based on a pure tone average of air-bone gap at 500 Hz, 1 kHz and 2 kHz or hearing level obtained from auditory brainstem response eudiometry. This study was approved by Research Ethics Committee (code number, FF-197-2008). Thirty-two ears were retrospectively evaluated. The postoperative hearing level of 30 dB and less was considered as successful hearing result postoperatively. Of the six ears which underwent canalplasty, three had achieved successful hearing result. However, there was no significant correlation between preoperative hearing level (HL) with HRCT score and postoperative HL with HRCT score at 0.05 significant levels (correlation coefficient = -0.292, P = 0.105 and correlation coefficient = -0.127, P = 0.810) respectively. Hearing evaluation and HRCT temporal bone are two independent evaluations for the patients with CAA before going for hearing reconstructive surgery.

Comparative study of hearing improvement in type 1 tympanoplasty with and without canalplasty

INTRODUCTION

Widening of the external auditory canal is canalplasty. It is an intergral part of tympanoplasty, especially in anterior perforations and gives wide surgical access for proper repair.

MATERIALS AND METHODS

After elevating tympanomeatal flaps the canal is widened using conical cutting and diamond burrs following which entire tympanic annulus is visible and corresponds to an inverted truncated cone.

RESULTS

Canalplasty gives 9 db gain in hearing compared to without canalplasty.

CONCLUSION

Canalplasty gives better visualization, better graft placement and better post-operative care.