Management of major post-cochlear implant wound infections

Case Report: Antibiotic Irrigation and Drainage Tube for Managing Chronic Suppurative Otitis Media After Cochlear Implantation

Cochlear implantation (CI) is the most effective solution for patients with severe-to-profound sensorineural hearing loss, especially in children. However, a major postoperative complication, known as chronic suppurative otitis media (CSOM), poses challenges for both doctors and families of the patients, which can affect post-CI hearing outcomes. We present the case of post-CI CSOM in a 15-year-old girl. She had been utilizing a unilateral cochlear implant for 7 years and had been experiencing intermittent earache and discharge in her only audible ear for the past 15 months. After antibiotic treatment failed to resolve her symptoms, we opted for a tympanomastoidectomy, and removed the receiver-stimulator package while keeping the electrode inside her cochlea. Simultaneously, we inserted an irrigation and drainage tube into the mastoid and middle ear space to discharge the exudate and control infection by applying topical antibiotics. The patient's ear discharge had resolved within 1 month, and her tympanic membrane healed naturally. Our successful experience shows that antibiotic irrigation and draining have effectively controlled infection and accelerated wound healing in this patient with post-CI CSOM, and it further prompted the patient to undergo bilateral CI 9 months later.

Cochlear Implantation After Head and Neck Radiation: A Case Series, Systematic Review, and Meta-analysis

OBJECTIVE

To determine if cochlear implant (CI) is safe and effective in patients with radiation therapy (XRT)-induced sensorineural hearing loss and to discuss considerations in this population through a retrospective cohort review, systematic review, and meta-analysis.

DATABASES REVIEWED

PubMed, Cochrane Library, and Embase.

METHODS

We retrospectively reviewed all CI cases after head and neck (HN) XRT at our institution, noting intraoperative findings, postoperative complications, and hearing outcomes. Change in speech discrimination scores (SDSs) was the primary outcome measure. Systematic review was performed to identify all cases of CI after HNXRT. A meta-analysis was performed to assess SDS change.

RESULTS

The retrospective cohort review identified 12 patients who underwent CI after HNXRT. One patient with HN cancer (HNC) and one with central nervous system pathology (CNSP) received bilateral implants. Six had HNC, three had CNSP, and one had Langerhans cell histiocytosis. Eleven had abnormal findings during CI. There were no postoperative complications. Twenty articles with an additional 97 patients were suitable for systematic review inclusion. Of the 109 patients, 67 (61.5%) had HNC and 18 (16.5%) had CNSP. Abnormal intraoperative findings were common (30.3%), most frequently in the mastoid (66.7%). Postoperative complications, including wound dehiscence and infection with some requiring explantation, occurred in 10.1% of patients. Sixty-six patients were included in the meta-analysis. All demonstrated SDS improvement (mean increase, 56.2%).

CONCLUSION

Patients with prior HNXRT benefit from CI. Paying careful attention to surgical planning and technique, postoperative care, and patient expectations is imperative, as complications are not uncommon.

Navigating Early and Late Hematomas in Cochlear Implantation: A Tri-Case Analysis

Cochlear implantation is a safe, popular procedure for severe hearing loss in both children and adults. Complications are categorized as major and minor, with hematomas and seromas being minor. This article discusses advanced diagnosis and treatment for three patients with post-implantation hematomas (two early, one late).

Classification of cochlear implant complications using a modified Clavien-Dindo classification

OBJECTIVES

Cochlear implantation (CI) surgery is a highly effective procedure for severe to profound hearing loss, with a low complication rate. There are currently multiple grading systems for CI surgery complications, making comparison of outcomes difficult. We propose a modification to the Clavien-Dindo classification of complications, and use this modified classification to analyse our complications.

METHODS

Complications were classified as: I - Self-limiting complications requiring no treatment or simple pharmacological therapies; II - Complications requiring pharmacological interventions other than those permitted under the criteria for Grade I, or non-invasive radiological imaging; IIIa - Complications necessitating surgical, radiological or endoscopic intervention, but excluding implant explantation and/or reimplantation. IIIb - Complications necessitating implant explantation and/or reimplantation.

RESULTS

1053 patients were recorded as having had at least one cochlear implant inserted with 114 complications reported in 90 patients. The 114 complications were classified into the proposed classification with 18 (15.7%) as Grade I, 36 (31.5%) as Grade II, 17 (14.9%) as Grade IIIa and 43 (34.2%) as Grade IIIb.

DISCUSSION

We found a low complication rate, and were able to use the modified Clavien-Dindo classification system to analyse our data. We would strongly advocate for a uniform reporting system and propose this modification of a widely used system.

Effect of Surface Tooling Techniques of Medical Titanium Implants on Bacterial Biofilm Formation In Vitro

The aim of this study was to assess the biofilm formation of Streptococcus mutans, Staphylococcus aureus, Enterococcus faecalis, and Escherichia coli on titanium implants with CAD-CAM tooling techniques. Twenty specimens of titanium were studied: Titanium grade 2 tooled with a Planmeca CAD-CAM milling device (TiGrade 2), Ti6Al4V grade 5 as it comes from CAD-DMLS device (computer aided design-direct metal laser sintering device) (TiGrade 5), Ti6Al4V grade 23 as it comes from a CAD-CAM milling device (TiGrade 23), and CAD-DMLS TiGrade 5 polished with an abrasive disc (TiGrade 5 polished). Bacterial adhesion on the implants was completed with and without saliva treatment to mimic both extraoral and intraoral surgical methods of implant placement. Five specimens/implant types were used in the bacterial adhesion experiments. Autoclaved implant specimens were placed in petri plates and immersed in saliva solution for 30 min at room temperature and then washed 3×with 1 ×PBS. Bacterial suspensions of each strain were made and added to the specimens after saliva treatment. Biofilm was allowed to form for 24 h at 37 °C and the adhered bacteria was calculated. Tooling techniques had an insignificant effect on the bacterial adhesion by all the bacterial strains studied. However, there was a significant difference in biofilm formation between the saliva-treated and non-saliva-treated implants. Saliva contamination enhanced S. mutans, S. aureus, and E. faecalis adhesion in all material types studied. S. aureus was found to be the most adherent strain in the saliva-treated group, whereas E. coli was the most adherent strain in the non-saliva-treated group. In conclusion, CAD-CAM tooling techniques have little effect on bacterial adhesion. Saliva coating enhances the biofilm formation; therefore, saliva contamination of the implant must be minimized during implant placement. Further extensive studies are needed to evaluate the effects of surface treatments of the titanium implant on soft tissue response and to prevent the factors causing implant infection and failure.

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.

Clinical profile and management of revision cochlear implant surgeries

OBJECTIVES

To discuss our experience with managing cochlear implant cases that required revision surgery.

METHODS

A retrospective case series study including data from 922 cochlear implant patients at an academic tertiary center was evaluated retrospectively. All patients who underwent revision cochlear implant (CI) surgery between January 2011 and July 2017 were included. The following data were collected: patient demographic data, details on the first implant, reasons for the revision, duration from initial implantation to revision, type of device, and management.

RESULTS

Out of 922 CI patients, 37 (4%) underwent revision surgery, comprising 33 children and 4 adults. The most common reason for revision surgery, at 28/37 cases (75.6%), was device failure. Surgical and medical aetiologies were responsible for 9/37 (24.3%) revisions. The mean duration from the initial implantation to the revision surgery was 29 months.

CONCLUSION

Revision CI surgery is not uncommon after initial implantation. Cochlear implant programs must implement long-term follow-up processes for CI users. Whenever a patient's rehabilitated performance regresses, the cause should be investigated to determine whether subsequent reimplantation is necessary.

Pressure ulcers and skin infections after cochlear implantation: A delayed yet serious issue

OBJECTIVES

Skin flap infection is one of the most common complications of cochlear implantation (CI). We identified the causes of skin flap pressure ulcer over the antenna site and proposed wound management strategies.

METHODS

A total of 250 consecutive pediatric patients who underwent CI to treat profound hearing loss were retrospectively assessed. Data on demographic characteristics, the cause of skin infection, and the time of onset were obtained.

RESULTS

Seventeen patients (17/250, 6.8%) had a total of 23 skin pressure injuries in the area covering the antenna. We used the National Pressure Ulcer Advisory Panel pressure injury staging system to grade injury severity. Twelve patients had 16 (16/23, 69.6.%) stage 1 pressure injuries; the skin reaction resolved after the patients stopped wearing the device for a brief period, loosened the magnet to relieve pressure on the coil, and received topical antibiotics. Five patients with six (6/23, 26.1%) stage 2 pressure injuries and one (1/23, 4.3%) stage 3 injury, were treated with oral antibiotics. The patient with the stage 3 injury was instructed not to wear the external device for 10-14 days. The incidence of skin reactions associated with the ESPrit speech processor (0/17, 0%) was significantly lower than that associated with the Freedom (2/17, 11.8%), N5 (8/17, 47.1%), and N6 (7/17, 41.1%; p < 0.05) processors. Pressure injuries were more common in younger children (≤7 years, 100%) than in older children (>7 years, 0%; p < 0.05) most likely due to their thinner scalps.

CONCLUSIONS

Early detection and treatment can prevent implant-threatening infections, particularly in younger children. We believe that better antenna designs will reduce this complication.

Microvascular free tissue transfer and cochlear implants: A case series and literature review

OBJECTIVE

The use of microvascular free tissue transfer (MVFTT) for defects of the scalp and lateral temporal bone in patients with cochlear implants (CI) is uncommon. Herein, we report our experience with the utility, indications, and outcomes for MVFTT in patients with cochlear implants.

METHODS

A retrospective review of patients at our institution from September 2016 to December 2017 identified subjects with coexistent cochlear implant and ipsilateral MVFTT of the lateral temporal bone or scalp. Information including demographics, indication for MVFTT, timing of CI and MVFTT, donor site, and previous radiation to the head and neck was collected. To assess the current literature on MVFTT in CI patients, a MEDLINE search was performed using key search terms.

RESULTS

Two patients with cochlear implants and MVFTT of the ipsilateral temporal bone or scalp were identified. One patient underwent MVFTT for advanced device extrusion with stable audiometric parameters rather than locoregional reconstruction or device explantation. The second patient had primary cochlear implantation at oncologic lateral temporal bone resection (LTBR) and MVFTT for locally advanced squamous cell carcinoma and concurrent profound sensorineural hearing loss (SNHL). A literature review identifies MVFTT as an option for advanced device extrusion, treatment of osteoradionecrosis, and reconstruction after primary oncologic surgery.

CONCLUSION

MVFTT is an important reconstructive tool for patients with functional, exposed cochlear implants. Cochlear implantation for severe to profound SNHL should be considered at the time of primary oncologic surgery and MVFTT of the lateral temporal bone or scalp.

LEVEL OF EVIDENCE

IV Laryngoscope, 130:1552-1557, 2020.

A systematic review on prevention and management of wound infections from cochlear implantation

OBJECTIVE OF REVIEW

Surgical site infections are a recognised complication of cochlear implant (CI) surgery with significant morbidity. Our aim was to search for the optimum prevention and management strategy to deal with this issue.

TYPE OF REVIEW

Systematic review.

SEARCH STRATEGY

A systematic literature search was undertaken from the databases of Embase, CINAHL, MEDLINE^® , Web of Science, Scopus and Cochrane Library according to the predefined inclusion and exclusion criteria.

EVALUATION METHOD

All relevant titles, abstracts and full-text articles were reviewed by two authors who resolved any differences by discussion and consultation with senior authors.

RESULTS

Fourteen articles were included in our review. The overall quality of evidence was low with the vast majority of the studies being retrospective case series and expert opinions. No randomised controlled trials were noted. We found consistent reports that intraoperative prophylactic antibiotics should be given to all patients undergoing CI and that the vast majority of CI wound infections had grown Staphylococcal spp. or Pseudomonas spp.

CONCLUSION

Our review has not identified any reliable or reproducible strategies to prevent and deal with wound infections after CI. We strongly encourage further research within this field and would suggest that a consensus of opinions from a multidisciplinary panel of experts may be a pragmatic way forward as an effective guide.

The Effect of Soft Tissue Infections on Device Performance in Adult Cochlear Implant Recipients

OBJECTIVE

The aim of this study was to examine the effect of cochlear implant (CI) site infection and its subsequent management on CI mapping and CI performance. Risk factors for CI infections and pathogens causing infections were reviewed. Treatment options for CI infections were examined.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Adult patients with a significant CI soft tissue infection from the Northern Cochlear Implant Programme, New Zealand over a 10-year period (August 2004 until August 2014).

INTERVENTION

Patients were treated with intravenous antibiotics, washout and debridement or ex-plantation and reimplantation of CI.

MAIN OUTCOME MEASURE

CI mapping results and implant performance before and after management of CI infections were compared.

RESULTS

There were nine CI infections. Most patients (7/9) were treated with washout and debridement. One patient required removal of the CI and one patient was deemed medically unfit for a general anaesthetic and was managed conservatively with antibiotics alone. Seven patients received long-term antibiotics. Four patients were able to maintain CI performance after salvage treatment of the CI infection. Three patients had poorer CI performance after salvage treatment. One patient had reimplantation and became a nonuser due to only partial reinsertion.

CONCLUSION

The pathophysiology of CI infections is complex. Infections can occur many years after CI surgery. The most common bacteria identified were Staphylococcus aureus, Pseudomonas aeruginosa, and skin commensals. Biofilms are present around implants that are removed from patients and biofilms may play a role in CI infections, but the mechanism of infection is not clear.

Delayed-onset haematoma formation after cochlear implantation

OBJECTIVE

This paper presents our experience on delayed-onset haematoma formation after cochlear implantation, a topic which has not been well discussed in the literature.

METHOD

Retrospective case review study.

RESULTS

Five children who had undergone cochlear implant surgery at 1.5 to 4 years of age (median, 2.5 years) were studied. The haematoma episodes occurred 2-12 years (median, 6 years) after cochlear implantation. Two patients had recurrent episodes. Two of the seven haematoma episodes were managed by needle aspiration alone, four by incision and drainage alone, and one by both needle aspiration and incision and drainage. Other than one patient with coagulopathy, there were no obvious predisposing factors, including trauma.

CONCLUSION

The majority of delayed-onset haematomas occurred without obvious predisposing factors. Needle aspiration can differentiate a haematoma from an abscess or cerebrospinal fluid leakage, and it provides an effective immediate therapeutic solution. However, aseptic techniques are emphasised to minimise the chances of an uncomplicated haematoma converting into a septic one.

Temporalis myofascial flap coverage for extrusion of internal device after cochlear implantation

Two pediatric patients with internal device exposure of cochlear implant (CI) were treated successfully using vascularized temporalis myofascial flaps. The visible scarring was minimal, and the CI function was excellent. Although we used temporalis myofascial flaps for late complications of an implanted ear, it can also be used in a primary case to provide flap reinforcement. In conclusion, the temporalis myofascial flap technique is an ultimate surgical option that offers advantages for CI patients with flap-related problems.

Bone-anchored hearing aid and skin graft removal with subsequent cochlear implantation

We describe a novel technique of scalp flap rearrangement for cochlear implant (CI) candidates who have previously undergone ipsilateral bone-anchored hearing aid (BAHA) placement. One patient with single-sided deafness (SSD) underwent removal of a BAHA with subsequent scalp rearrangement for coverage of the implant site. After adequate healing of the scalp rotational flap, he underwent uncomplicated cochlear implantation without soft tissue complications. With increasing utilization of CIs in SSD, there will be more patients undergoing cochlear implantation who have previously had a BAHA. We present a novel method for accomplishing this goal while minimizing the risk of soft tissue complications. Laryngoscope, 126:2601-2604, 2016.

A case report of a cochlear implant infection - A reason to explant the device?

CLINICAL PRESENTATION

Case history of a paediatric patient with a cochlear implant and a surgical site infection that developed as a result of acute otitis media is presented.

INTERVENTION

After conservative management including wound debridement it was decided to explant a functioning device.

OBJECTIVE AND IMPORTANCE

In a number of cases, it is necessary to remove the infected albeit functioning device, especially in the event of formation of the biofilm has occurred. It is necessary to review and evaluate the methods with which these major complications are routinely managed with the aim to increase the survival ratio for the implanted device.

Skin flap complications after cochlear implantations

The objective of the study was to analyse and present the surgical management strategy for major skin flap complications (MSFC) after cochlear implantations. Patients fitted with a titanium-silicone-coated implant of the same kind, operated on between 1994 and 2013 with a standardised procedure (1076 medical charts) were analysed. Analysis aimed to identify and study individuals with skin problems related to the cochlear implant treatment, i.e. requiring surgical treatment in hospital defined as MSFC and focused on incidence, risk factors and treatment of MSFC. MSFC were diagnosed in 1.76 % of patients: 2.06 % of children and 1.35 % of adults, 2.43 % after implantation with a long "C"-shaped incision and 1.28 % after short retroauricular incision. Registered risk factors included head trauma, acute otitis media, poor hygiene in children, and general comorbidities in adults. The primary intervention was dependent on skin complication severity and included revision surgery with wound closure over an implant (52.6 %) and revision surgery with explantation (47.4 %). Revision surgery without explantation was successful in 40 % and the most effective approach was debridement with a two-layer rotational flap. Explantation led to ultimate wound healing in all cases. Major skin flap complications after cochlear implantation are rare, but their treatment is complex and difficult. Revision surgery with resection of infected tissue, formation of a rotational two-layer flap preceded and supplemented by intensive targeted antibiotic therapy can be effective and should be the first treatment option. Spontaneous implant explantation, abscess formation or unsuccessful primary treatment necessitate implant removal as the ultimate solution.

Electrode array extrusion through the posterior canal wall presenting as a delayed post-cochlear implant complication

OBJECTIVES AND IMPORTANCE: Cochlear implantation is an established, reliable, and safe procedure with a low complication rate. Electrode array extrusion through the posterior aspect of external ear canal is a potential major complication of cochlear implant surgery that may result in revision surgery or explantation. Although there have been previous case reports of such extrusions through the tympanic membrane, this is the first well-documented report of an extrusion through the posterior canal wall which was previously intact.

CLINICAL PRESENTATION

In this case report, we present a case of electrode array extruding through an initially intact posterior canal wall presenting as a delayed post-operative complication in a 13-year old Asian boy.

INTERVENTION

With reference to existing relevant literature, the case is discussed focusing on its management, possible contributing factors, and prevention strategies.

CONCLUSION

Excessive thinning of the bony wall should be avoided as it can potentially break down. Abutment on the posterior canal wall by a coiled electrode array in the mastoid cavity exerting undue pressure on the bony wall can further contribute to additional stress. The implant surgeon must be cognizant of mastoid growth patterns in children. Life-long regular follow-up in implanted patients is crucial.