Recurrent extrusion of cochlear implant at an interval of 5 years

A Descriptive Study on Imperiled Cochlear Implant Salvage Using Double Flap Cover-What We Learned in 6 Years

Cochlear implant surgery is the standard of care for severe sensorineural hearing loss. Infection followed by implant extrusion is an infrequent complication of this surgery. The ideal treatment is explantation of the implant. However, implant removal and reimplantation is a challenging surgery and may have poor speech reception outcomes. The cost of a new implant especially in developing countries is also a deterrent. Our study dwells on the feasibility of salvaging exposed cochlear implants by a combination of pericranial flaps followed by a scalp flap cover. The study was done in a tertiary care hospital over a period of six years. Out of 303 cochlear implant surgeries, 12 patients had implant exposure and extrusion. Patients having meningitis and sepsis were excluded from the study. All patients underwent debridement and cover with double flap (Pericranial flaps and scalp rotation flap). The average operating time was 2.17 h. The surgery is technically simple with a short learning curve. It brings in rich blood supply and there is fair amount of tissue mobility. In 11 patients we were able to salvage the implant. Patients were followed for a period of 01 year post operatively. Our study suggests that salvage of infected implant should be attempted as it is feasible, durable and effective in appropriate patients.

Salvaging Exposed Cochlear Implants

The cochlear implant (CI) procedure is one of the most efficient surgical options for the management of patients suffering from severe bilateral sensorineural hearing loss. Notably, CI exposure is one of the most commonly reported complications. Herein, we report our experience in the management of three patients with CIs complicated by implant exposure.

The temporoparietal fascia flap for coverage of cochlear reimplantation following extrusion

The management of cochlear implant extrusion (CIE) can be challenging, particularly in the pediatric population in whom reconstructive options are limited. We describe the use of the temporoparietal fascia flap (TPFF) for this purpose due to its ease of use and limited morbidity. We present a case series of two pediatric patients who underwent explantation of their devices, followed by reimplantation with TPFF coverage. Our experience provides evidence that the TPFF can be used to prevent further CIE through a postauricular incision following cochlear reimplantation with successful long-term results.

Systematic Review and Meta-analysis of Surgical Complications following Cochlear Implantation in Canal Wall Down Mastoid Cavities

Objective

We sought to assess the complication rates following cochlear implantation in canal wall down mastoid cavities in adults and children.

Data Sources

A systematic review of English articles from PubMed, Web of Science, EMBASE, and the Cochrane Library. Additional studies were identified by reviewing the reference lists of the originally identified studies.

Review Methods

Studies were included that reported on surgical outcomes following cochlear implantation in canal wall down mastoid cavities. Two authors, using predefined data fields, independently reviewed all articles while tabulating study quality indicators. A meta-analysis of proportions was conducted on select cohorts to determine weighted complication rates.

Results

Forty-two articles were included that accounted for 424 patients and described surgical outcomes following cochlear implantation in canal wall down mastoid cavities. In a comparison of the postoperative complication rates, overclosing the external auditory meatus had significantly fewer global complications than did maintaining a canal wall down mastoid cavity ( P = .027). In a comparison of the complication rates (1) between staging the cochlear implantation and performing external auditory meatus overclosure simultaneously with cochlear implantation and (2) between pediatric and adult cochlear implantation recipients with external auditory meatus overclosure, there were no significant differences ( P = .085 and P = .92, respectively).

Conclusion

Overclosing the external auditory meatus at the same time of cochlear implantation leads to significantly fewer complications when compared with maintaining a canal wall down mastoid cavity with soft tissue coverage of the electrode array.

Results, Hearing Rehabilitation, and Follow-up with Magnetic Resonance Imaging after Tympanomastoid Exenteration, Obliteration, and External Canal Overclosure for Severe Chronic Otitis Media

Objectives:

We sought to evaluate the results, auditory rehabilitation, and follow-up with magnetic resonance imaging (MRI) after tympanomastoid exenteration with obliteration of the mastoid cavity and overclosure of the external ear canal in patients with severe chronic otitis media that was resistant to medical therapy and conventional surgery and was associated with a profound sensorineural or severe conductive hearing loss.

Methods:

Twenty-nine patients were analyzed and underwent this surgical technique. Twelve patients had, during the same or later stage, either cochlear implantation, fixture implantation for a bone-anchored hearing aid, or middle ear implantation. For follow-up control of the obliterated cavity, delayed gadolinium-enhanced, T1-weighted MRI in combination with non-echo planar imaging diffusion weighted sequences were used.

Results:

No patient had recurrent otorrhea after an average follow-up period of 4.75 years. One patient had a residual cholesteatoma as shown by new MRI techniques, and this was successfully resected. One patient developed complications 6 months after 1-stage tympanomastoid exenteration and cochlear implantation.

Conclusions:

This technique is very useful in selected patients with severe chronic otitis media that is resistant to medical therapy and surgery and is associated with a profound sensorineural or severe conductive hearing loss. New sequences in MRI are used for postoperative follow-up of these obliterated cavities and seem reliable for the detection of residual or recurrent cholesteatoma. Middle ear implantation and cochlear implantation can be relatively safely performed in these patients in a second stage.

Biofilm formation in an in vitro model of cochlear implants with removable magnets

Background

Cochlear implant (CI) recesses, such as the removable magnet pocket, appear to harbor more biofilm than smooth surfaces. The aim of this study was to examine the impact of removable magnets on biofilm formation in an in vitro model.

Methods

Silastic models were constructed to represent CIs with and without a magnet pocket and with and without a titanium blank in the pocket. CIs were exposed to a culture of a biofilm forming strain of Staphylococcus aureus. Adherence of planktonic bacteria and biofilm formation were assessed with quantitative bacterial counts and scanning electron microscopy.

Results

Adherent bacterial counts were significantly higher in CI models with an empty magnet pocket ( P = 0.0097). Biofilm formation was significantly lower in CI models without a magnet pocket ( P = 0.0121).

Conclusions

CI magnet pockets harbor bacteria that can increase biofilm development in an in vitro model.

Cochlear Implantation in Canal Wall Down Mastoid Cavities

Cochlear implantation in canal wall down mastoid (CWD) cavities is fraught with the issue of how best to manage the mastoid cavity. Decision points include whether the external auditory meatus should be overclosed, whether the implantation should be staged, or even if the eustachian tube should be plugged. Given these options, we sought to describe our experience of cochlear implantation in CWD cavities. Among evaluation of subjects ≥18 years of age, 9 had cochlear implants placed in CWD mastoid cavities, 7 of which had the external auditory meatus overclosed, while 2 maintained open cavities following implantation. With an average follow-up of 36.7 months (median, 22.8 months), 2 subjects who had overclosure developed meatal dehiscences requiring further intervention, while no complications were observed in the 2 patients who maintained open cavities.

Long-term outcome of cochlear implant in patients with chronic otitis media: one-stage surgery is equivalent to two-stage surgery

This study compared long-term speech performance after cochlear implantation (CI) between surgical strategies in patients with chronic otitis media (COM). Thirty patients with available open-set sentence scores measured more than 2 yr postoperatively were included: 17 who received one-stage surgeries (One-stage group), and the other 13 underwent two-stage surgeries (Two-stage group). Preoperative inflammatory status, intraoperative procedures, postoperative outcomes were compared. Among 17 patients in One-stage group, 12 underwent CI accompanied with the eradication of inflammation; CI without eradicating inflammation was performed on 3 patients; 2 underwent CIs via the transcanal approach. Thirteen patients in Two-stage group received the complete eradication of inflammation as first-stage surgery, and CI was performed as second-stage surgery after a mean interval of 8.2 months. Additional control of inflammation was performed in 2 patients at second-stage surgery for cavity problem and cholesteatoma, respectively. There were 2 cases of electrode exposure as postoperative complication in the two-stage group; new electrode arrays were inserted and covered by local flaps. The open-set sentence scores of Two-stage group were not significantly higher than those of One-stage group at 1, 2, 3, and 5 yr postoperatively. Postoperative long-term speech performance is equivalent when either of two surgical strategies is used to treat appropriately selected candidates.

[Study of a case of cochlear implant with recurrent cutaneous extrusion]

OBJECTIVE

An observation of a difficult-to-diagnose complication of the cochlear implant: recurring cutaneous extrusion of a cochlear implant is reported.

PATIENTS AND METHODS

The history of an adult patient with total deafness is reported. She received an implant in her right ear in 1988, which was then explanted because of absence of hearing results. She received a second implant in her left ear in 2002, which was then explanted in 2007 because of cutaneous extrusion. In 2008, a second implant of a different brand was placed in her left ear, with the central part placed away from the first site, but extrusion recurred. A new attempt to encapsulate the central part with a hydroxyapatite box also ended in extrusion and was explanted in 2008.

RESULTS

Various diagnoses to explain these cutaneous problems were suggested during this clinical progression: infection, allergy, and a reaction to a foreign body. No hypothesis could be clearly ruled out.

CONCLUSION

Cutaneous complications after cochlear implant are exceptional. As soon as cutaneous disorders appear, a rigorous diagnostic process must be followed so that the patient can be recommended a long-lasting solution to restore quality hearing.

Cochlear implantation in patients with chronic otitis media: 7 years' experience in Maastricht

The purpose of this paper is to propose management options for cochlear implantation in chronic otitis media (COM) based on our 7-year experience. Thirteen patients with COM who were candidates for cochlear implantation were identified. COM was divided in an inactive and an active form based on clinical and radiological findings. One major complications and one minor complication were identified in the study group. In case of an active infection or in case of a unstable cavity we advise cochlear implantation as a staged procedure. A single stage procedure is recommended in case of patients with COM presenting with a dry perforation or a stable cavity.

Silicone Allergy

OBJECTIVE

We introduce silicone allergy as a rare cause for cochlear implant extrusion and discuss its management.

STUDY DESIGN

Retrospective case series and literature review.

SETTING

Tertiary referral centers.

PATIENTS

Primary eligibility criteria included patients who experienced a delayed extrusion of their cochlear implants with negative wound cultures and had a suspected or a test-proven allergy to silicone components of an implant.

INTERVENTIONS

Silicone allergy testing, explantation of a cochlear implant containing allergenic silicone materials, reimplantation with a custom-made cochlear implant excluding an allergenic silicone component.

OUTCOME MEASURES

Uneventful wound healing and extrusion-free long-term follow-up after the reimplantation with a custom-made cochlear implant excluding an allergenic silicone component.

RESULTS

Three known cases of cochlear implant extrusion as a result of silicone allergy have been noted from 1991 through 2004 in three cochlear implant programs in the United States. All three devices extruded, resulting in explantation of the old device and reimplantation with a new custom-made device eliminating the allergenic silicone component. Wound cultures were negative in all cases. All three patients experienced a delayed extrusion of their devices. Two of these patients had a test-proven allergy to the implant's silicone components, whereas the third patient was presumed to have a hypersensitivity solely on the basis of a clinical presentation.

CONCLUSION

We propose that silicone allergy is a rare cause of cochlear implant extrusion. Patients experiencing cochlear implant extrusion, particularly with a delayed onset and negative wound culture results, should be tested for silicone allergy.

Cochlear Implant Explantation as a Sequela of Severe Chronic Otitis Media

INTRODUCTION

In the 1980s, intracranial and inner ear infections were feared complications in patients with recurrent or chronic otitis media (COM) who had undergone cochlear implantation. Current studies show a low incidence of such complications. We present a case of a patient who developed severe COM requiring cochlear explantation.

CASE

Our patient had a previous cleft palate repair and as a three-year-old was implanted with a Nucleus-24 implant. She developed chronic otorrhea in the implanted ear, which was managed by her pediatrician until her cochlear implant stopped functioning. Radiographic imaging revealed erosion of the cochlea and extrusion of the distal electrode medially in the petrous apex.

SETTING

Tertiary care university hospital.

INTERVENTION/RESULTS

The patient underwent cochlear explantation, subtotal petrosectomy, obliteration of ear, and intravenous antibiotic therapy. One month later she was implanted in the contralateral ear.

CONCLUSION

COM poses potentially severe complications in patients receiving cochlear implants. Patients receiving cochlear implants who are at high risk for COM require follow-up for an extended period of time.

Rescuing the imperiled cochlear implant: a report of four cases

OBJECTIVE

To report experience with exposed cochlear implants in patients with risk factors that may contribute to flap failure.

STUDY DESIGN

Retrospective review.

SETTING

University-based tertiary referral center.

PATIENTS

Four patients with exposed cochlear implants who presented with various risk factors that compromise healing.

INTERVENTION

After beginning antibiotic therapy, we took steps to correct the thyroid levels and blood glucose levels when indicated. We administered hyperbaric oxygen therapy in one case. At surgery, we debrided all devitalized and infected tissue. In one case, it was necessary to obliterate the mastoid bowl and relocate the device to a different site around the ear. In all four cases, we covered the implant with well-vascularized rotation flaps.

MAIN OUTCOME MEASURES

Wound healing, resolution of infection, and preservation of implant function.

RESULTS

In each case, the infection cleared and the implant covered. Nevertheless, one of the patients suffered implant failure 6 months after salvage surgery, and another suffered implant failure 3 years after salvage.

CONCLUSION

All exposed or infected implants need not be removed. By using sound wound handling technique and by optimizing the patient's medical status, many exposed implants can be salvaged.

The role of biofilms in otolaryngologic infections

PURPOSE OF REVIEW

Bacterial biofilms have recently been shown to be important in diseases of the head and neck. Because the concept of biofilms is novel to most practitioners, it is important to gain a basic understanding of biofilms and to recognize that strategies developed to treat planktonic bacteria are ineffective against bacteria in a biofilm.

RECENT FINDINGS

Bacteria preferentially exist in complex, surface-attached organizations known as biofilms. Bacteria in biofilms express a different set of genes than their planktonic counterparts and have markedly different phenotypes. Biofilm bacteria communicate with each other, and have mechanisms to diffuse nutrients and dispose of waste. Biofilms provide bacteria with distinct advantages, including antimicrobial resistance and protection from host defenses. Thus, bacteria exist in a far more complex fashion than previously thought and can best be thought of as "self-assembling multicellular communities." Although a focus on the planktonic form of bacteria has been useful in understanding acute infections, chronic infections are much better understood as biofilm illnesses. Biofilms have been shown to be involved in chronic otitis media, chronic tonsillitis, cholesteatoma, and device-associated infections.

SUMMARY

Now that basic research has demonstrated that the vast majority of bacteria exist in biofilms, the biofilm concept of disease is beginning to spread throughout the clinical world. Understanding that many of the infections that affect structures of the head and neck are actually biofilm related is fundamental to developing rational strategies for treatment and prevention.