Keyhole Cochlear Implantation: Current Status

Various approaches to the round window for cochlear implantation: a systematic review

OBJECTIVE

Round window approaches are used to insert a cochlear implant electrode array into the scala tympani. This study aimed to review the literature to find the reported round window approaches.

METHOD

This review was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analyses ('PRISMA') guidelines. Articles that described their surgical approach to the round window were included. The PubMed, Scopus, Web of Science and Cochrane Library electronic databases were searched through to June 2021. The study protocol was registered on Prospero (reference number: CRD42021226940).

RESULTS

A total of 42 reports were included. The following approaches were documented: the standard facial recess, keyhole, retrofacial, modified suprameatal, transaditus, combined posterior tympanotomy and endomeatal, modified Veria, canal wall down approaches, and endoscopically assisted technique.

CONCLUSION

This review suggested that there are numerous distinct round window approaches, providing alternatives when the round window is inaccessible through the standard facial recess.

Safety of Cochlear Implantation in Children 12 Months or Younger: Systematic Review and Meta-analysis

OBJECTIVE

To systematically review the literature to determine safety of cochlear implantation in pediatric patients 12 months and younger.

DATA SOURCE

Ovid MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched from inception to March 20, 2021.

REVIEW METHODS

Studies that involved patients 12 months and younger with report of intraoperative or postoperative complication outcomes were included. Studies selected were reviewed for complications, explants, readmissions, and prolonged hospitalizations. Two independent reviewers screened all studies that were selected for the systematic review and meta-analysis. All studies included were assessed for quality and risk of bias.

RESULTS

The literature search yielded 269 studies, of which 53 studies underwent full-text screening, and 18 studies were selected for the systematic review and meta-analysis. A total of 449 patients and 625 cochlear implants were assessed. Across all included studies, major complications were noted in 3.1% of patients (95% CI, 0.8-7.1) and 2.3% of cochlear implantations (95% CI, 0.6-5.2), whereas minor complications were noted in 2.4% of patients (95% CI, 0.4-6.0) and 1.8% of cochlear implantations (95% CI, 0.4-4.3). There were no anesthetic complications reported across all included studies.

CONCLUSION

The results of this systematic review and meta-analysis suggest that cochlear implantation in patients 12 months and younger is safe with similar rates of complications to older cohorts.

Cochlear Implant Complications in Children and Adults: Retrospective Analysis of 148 Cases

Objective

This study aimed to establish and discuss the intraoperative and postoperative complications affecting patients who underwent cochlear implant (CI) surgery from the Cochlear Implant Program of King Abdulaziz University Hospital (KAUH), Jeddah, Saudi Arabia.

Methods

A retrospective study was conducted by reviewing the medical records of 148 patients who underwent cochlear implantation at KAUH between 1999 and 2019. Postoperative complications were classified into minor and major complications. Minor complications resolved with minimal or no treatment. Major complications required additional surgery or hospitalization.

Results

Complications occurred in 28 (18.9%) patients. Minor complications occurred in 17 (11.5%) patients, which included otitis media (2%), facial palsy (1.4%), wound infection (1.4%), vertigo (1.4%), intraoperative cerebrospinal fluid (CSF) gusher (1.4%), tinnitus (1.4%), facial stimulation (1.4%), hematoma (0.7%), and chorda tympani nerve injury (0.7%). Major complications occurred in 11 (7.4%) patients. These included flap dehiscence/infection (2%), device failure (1.4%), device migration (1.4%), mastoiditis (1.4%), electrode damage during insertion (0.7%), and misplaced electrodes (0.7%).

Conclusion

This study reported a low rate of surgical complications associated with CI, and most have been managed successfully without further complications. Our results prove that CI is a safe and reliable procedure, with a low complications rate when performed by experienced surgeons.

Analysis and Management of Complications in a Cohort of 1,065 Minimally Invasive Cochlear Implantations

Objectives:

To analyze complications associated with minimally invasive cochlear implantation by comparing data from different centers, to discuss major reasons for complications, and to refine implantation techniques to decrease them.

Patients:

Patients who underwent cochlear implantation at our center by the same surgeon (the corresponding author of this article) from March 2006 to March 2015 were enrolled.

Intervention:

First, a retrospective analysis of the complications associated with minimally invasive cochlear implantation at our center was performed. Second, published reports from other centers that describe complications were reviewed. Differences between complications in our cohort and other studies were evaluated.

Main Outcome Measure:

Strategies for reducing complications were assessed and modifications in surgical protocol proposed accordingly.

Results:

In total, 1,014 patients underwent 1,065 cochlear implantations. There were 28 complications (7 major, 21 minor) and only 2 reimplantations for the entire cohort, with no case of severe infection, flap necrosis, or device extrusion. The major complications were electrode misplacement, magnet displacement, implant failure secondary to trauma, and temporary cerebrospinal fluid leakage. The rates of major complications in our cohort were very low (0.6%) compared with those in the literature.

Conclusion:

Preoperative surgical planning based on individual patient anatomy and employment of soft surgical techniques can minimize surgical complications.

Cochlear implant fixation using a subperiosteal tight pocket without either suture or bone-recess technique

OBJECTIVES/HYPOTHESIS

To assess the complication and migration rates associated with the fixation of cochlear implant receiver-stimulators using a subperiosteal tight pocket without either suture fixation or bone recession.

STUDY DESIGN

Dual-institution retrospective case review.

METHODS

A retrospective case review was conducted at two tertiary referral centers. All patients who underwent cochlear implantation with device fixation using a subperiosteal tight pocket without suturing over the device or recessing of the receiver stimulator in bone were identified. There was a minimum follow-up period of 6 months. Outcome measures included intraoperative and postoperative complications, including evidence of device migration associated with interference with external device use or the need for revision surgery. Other outcome measures included soft tissue flap complications.

RESULTS

Sixty-two patients were identified with a mean age of 39 years, (range 1.5-5 years). The average follow-up period was 32.6 months (range 6-120 months). Device manufacturers included Cochlear Corporation (Denver, CO) (n=44), MED-EL (Durham, NC) (n=12), and Advanced Bionics (Valencia, CA) (n=6). There were no associated intraoperative complications related to subperiosteal pocket fixation of the receiver stimulator, and no cases of migration were identified.

CONCLUSION

Fixation of the cochlear implant receiver stimulator using a subperiosteal tight pocket without either suture fixation or bone recession has been demonstrated to be feasible across a range of patient demographics and cochlear implant devices. This method of fixation appears to allow for an efficient and minimally invasive approach without compromising patient safety or device performance.

LEVEL OF EVIDENCE

4.