Chronic suppurative otitis media following paediatric cochlear implantation

Endoscope-Assisted Cochlear Implantation

OBJECTIVES

Our aim was to present our endoscope-assisted cochlear implantation (CI) technique, in which the middle ear landmarks were identified through the facial recess exposure by using an endoscopic view without elevating the tympanic annulus. The secondary goal was to assess whether the situation of difficult surgical exposure could be predicted by evaluating preoperative axial computed tomography (CT) examinations.

METHODS

CT examinations and surgical outcomes of endoscope-assisted CI surgeries were analyzed.

RESULTS

A total of 179 CI operations performed in 27 adults (15.1%) and 152 children (84.9%) were retrospectively evaluated. It was found that in 14 cases (7.8%), endoscopic examination contributed substantially in identifying the round window (RW) membrane correctly. Endoscopic identification of the RW through the posterior tympanotomy enabled us to perform a straightforward surgery in all these cases, without the need for switching to a bony cochleostomy or alternative surgical techniques. The difficulty in the surgical exposure was predicted preoperatively by examining the axial CT scans in six of the 14 cases (42.8%) for which endoscopic assistance was necessary in order to identify the RW correctly.

CONCLUSION

The main benefit of endoscope-assisted CI is the improved visibility leading to a panoramic view of the RW region. The implementation of transfacial recess endoscopic examination into the conventional CI technique is helpful to avoid problems during surgical orientation. However, the difficulty in the surgical exposure of the RW cannot be reliably predicted by the subjective evaluation of preoperative CT scans and more studies are needed to obtain reliable criteria.

Impact of Chronic Suppurative Otitis Media in Pediatric Cochlear Implant Recipients-Insight into the Challenges from a Tertiary Referral Center in UK

OBJECTIVE

Analyze the presentation and evolution of chronic suppurative otitis media (CSOM) in children with cochlear implants (CI) and explore the merit of early intervention.

STUDY DESIGN

Retrospective patient review.

SETTING

Tertiary referral hospital and cochlear implant programme.

PATIENTS

Children with a CI who developed CSOM.

INTERVENTION

Tympanoplasty.

MAIN OUTCOME MEASURES

Disease control, recurrence of cholesteatoma, cochlear implant preservation.

RESULTS

Eight children fit our inclusion criteria with a mean follow up of 8 years. Onset of CSOM symptoms was observed on an average of 5 years after implantation (range, 2-13 yr) and led to surgical intervention in an average of 15.6 months following symptom onset. Cholesteatoma was found in four of the eight patients. Of these, one patient underwent a subtotal petrosectomy and explantation with reimplantation at the same stage but the reimplant failed to function and was explanted subsequently. One patient was initially managed by a canal wall up mastoidectomy and explantation but went on to require subtotal petrosectomy and labyrinthectomy for recurrent disease. One patient underwent a subtotal petrosectomy with explantation and is awaiting a reimplantation. The fourth patient had limited disease around the electrodes that was excised without compromising the implant. In the group of patients with CSOM without cholesteatoma, one underwent an explantation due to recurrent ear infections and a subsequent cartilage tympanoplasty for a retracted eardrum. The remaining three patients underwent successful excision of retraction pockets and repair of eardrums using cartilage with the implant in situ. A mean follow up of 2 years after the implant preservation surgeries shows good functioning of the CI.

CONCLUSION

Early recognition of CSOM is paramount in patients with CI as delay in treatment can result in the infection spreading via the cochleostomy resulting in loss of the cochlea. Recurrent ear infections in an implanted ear should prompt early examination to exclude the presence of middle ear disease, which may require anesthesia in a young child.

Congenital cholesteatoma and cochlear implantation: Implications for management

INTRODUCTION

Cholesteatoma is an uncommon condition that has occasionally been associated with cochlear implantation (CI). Cases of secondary acquired cholesteatoma have been described, in which intra-operative breech of the posterior canal wall is thought to be a contributing factor. Primary acquired cholesteatoma is not typically associated with congenital sensorineural hearing loss (SNHL) or CI in children. Congenital cholesteatoma is a rarer entity yet with an incidence in the literature of 2‐4% of all cholesteatomas. We present lessons learned from our experience of congenital cholesteatoma in CI candidates.

METHODS

Retrospective reviews of departmental CI and cholesteatoma databases in a tertiary/quaternary pediatric center were conducted. Cases of congenital cholesteatoma were identified. The proportion of congenital cholesteatoma cases in CI candidates was compared with number of acquired cholesteatoma. Optimum management of congenital cholesteatoma in CI candidates was reviewed.

RESULTS

In our pediatric CI population, 2/794 patients (0.25%) were recognized as having a congenital cholesteatoma during their evaluation for CI. No cases of primary acquired cholesteatoma were identified in this population at presentation or at follow up to 18 years.

DISCUSSION

The 0.25% incidence of congenital cholesteatoma in our population of CI patients is higher than expected of this rare condition. It is surprisingly common given the absence of any cases of primary acquired cholesteatoma, which is considerably more common even in the pediatric population. Both patients likely had an inherited form of hearing loss and a genetic contribution to the presence of congenital cholesteatoma cannot be excluded. The presence of congenital cholesteatoma has implications for the algorithm currently employed for the assessment of CI. We consider that surgery should be staged to ensure complete removal of the cholesteatoma before implantation. Thus bilateral CI should be provided sequentially rather than simultaneously in the presence of unilateral cholesteatoma.

Pediatric cholesteatoma and variants in the gene encoding connexin 26

OBJECTIVES/HYPOTHESIS

Connexin 26 is a gap junction protein encoded by the GJB2 gene. It is expressed in cholesteatoma, and mutations cause proliferative skin disorders and sensorineural hearing loss (SNHL). Deletions of GJB6, which encodes connexin 30, cause SNHL in a digenic manner with a heterozygous GJB2 mutation. We hypothesize that GJB2 and GJB6 mutations might influence the development of cholesteatoma.

STUDY DESIGN

Prospective observational study to identify GJB mutations in pediatric cholesteatoma.

METHODS

Peripheral blood samples from 98 children with cholesteatoma were screened for mutations in the GJB2 gene by direct sequencing of the coding region (exon 2 and the intron/exon boundary). Deletions of the GJB6 gene were tested using multiple ligation probe amplification methods. GJB status was compared with other populations and patient age and extent of cholesteatoma at presentation.

RESULTS

Fourteen children had at least one GJB2 variant (14%). Of these, three had two variants. Two of the variants were neutral polymorphisms. One child with the GJB2 genotype 35delG/35delG also had SNHL. No correlation was found between GJB2 status and patient age or cholesteatoma severity at presentation. No GJB6 deletions were found.

CONCLUSIONS

GJB2 gene variants are present in a minority of children with cholesteatoma, but may be more common than in normal populations. It is conceivable that alterations of connexin 26 expression could contribute to the multifactorial disease process in cholesteatoma by modifying the cell-to-cell communication that is important in proliferation and migration of keratinocytes.