Physical outcome measures for conductive and mixed hearing loss treatment: A systematic review.

BACKGROUND: The number of potential options for rehabilitation of patients with conductive or mixed hearing loss is continually expanding. To be able to inform patients and other stakeholders, there is a need to identify and develop patient-centred outcomes for treatment of hearing loss. OBJECTIVE OF REVIEW: To identify outcome measures in the physical core area used when reporting the outcome after treatment of conductive and mixed hearing loss in adult patients. TYPE OF REVIEW: Systematic review. SEARCH STRATEGY: Systematic review of the literature related to reported physical outcome measures after treatment of mixed or conductive hearing loss without restrictions regarding type of intervention, treatment or device. EVALUATION METHOD: Any measure reporting the physical outcome after treatment or intervention of mixed or conductive hearing loss was sought and categorised. The physical outcome measures that had been extracted were then grouped into domains. RESULTS: The literature search resulted in the identification of 1434 studies, of which 153 were selected for inclusion in the review. The majority (57%) of papers reported results from middle ear surgery, with the remainder reporting results from either bone conduction hearing devices or middle ear implants. Outcomes related to complications were categorised into 17 domains, whereas outcomes related to treatment success was categorised into 22 domains. CONCLUSIONS: The importance of these domains to patients and other stakeholders needs to be further explored in order to establish which of these domains are most relevant to interventions for conductive or mixed hearing loss. This will allow us to then assess which outcome measures are most suitable for inclusion in the core set.

Audiological outcome of stapes surgery for far advanced cochlear otosclerosis.

BACKGROUND: Patients with advanced otosclerosis can present with hearing thresholds eligible for cochlear implantation. This study sought to address whether stapes surgery in this patient group provides a clinically significant audiological benefit. OBJECTIVES: To assess pre- and post-operative hearing outcomes of patients with advanced otosclerosis, and to determine what proportion of these patients required further surgery including cochlear implantation. METHODS: Between 2002 and 2015, 252 patients underwent primary stapes surgery at our institution. Twenty-eight ears in 25 patients were deemed to have advanced otosclerosis, as defined by pure audiometry thresholds over 80 dB. The patients' records were analysed to determine audiological improvement following stapes surgery, and assess whether any further surgery was required. RESULTS: The audiological outcome for most patients who underwent primary stapes surgery was good. A minority of patients (7 per cent) required revision surgery. Patients who underwent cochlear implantation after stapes surgery (10 per cent) also demonstrated a good audiological outcome. CONCLUSION: Stapes surgery is a suitable treatment option for patients with advanced otosclerosis, and should be considered mandatory, before offering cochlear implantation, for those with a demonstrable conductive component to their hearing loss. A small group of patients get little benefit from surgery and subsequently a cochlear implant should be considered.

A case of conservatively managed invasive ceruminoma and a review of the literature.

Ceruminomas are rare tumours arising from the apocrine sweat glands of the ear canal. We present a case of a malignant ceruminoma, which was managed with local surgical excision only rather than the wider clearance more commonly undertaken with these invasive neoplasms. We present the clinical case, histological analysis, and clinical progression for this patient and review the literature on this uncommon pathology.

Simplified bone-anchored hearing aid insertion using a linear incision without soft tissue reduction.

BACKGROUND: Numerous techniques have been described to manage the skin and other soft tissues during bone-anchored hearing aid insertion. Previously, generally accepted techniques have sometimes led to distressing alopecia and soft tissue defects. Now, some surgeons are rejecting the originally described split skin flap in favour of a less invasive approach. OBJECTIVE: To investigate bone-anchored hearing aid placement utilising a single, linear incision with either no or minimal underlying soft tissue reduction. PATIENTS AND METHODS: Thirty-four adults were prospectively enrolled to undergo single-stage bone-anchored hearing aid placement with this modified technique. A small, linear incision was used at the standard position and carried down through the periosteum. Standard technique was then followed with placement of an extended length abutment. Patients were reviewed regularly to assess wound healing, including evaluation with Holgers' scale. RESULTS: Only 14.7 per cent of patients had a reaction score of 2 or higher. Most complications were limited to minor skin reactions that settled with silver nitrate cautery and/or antibiotics. None required revision surgery for tissue overgrowth, and there were no implant failures. CONCLUSION: Our results suggest this to be a simple and effective insertion technique with favourable cosmesis and patient satisfaction.

Relations between cochlear histopathology and hearing loss in experimental cochlear implantation.

This study reviews the cochlear histology from four hearing preservation cochlear implantation experiments conducted on 73 guinea pigs from our institution, and relates histopathological findings to residual hearing. All guinea pigs had normal hearing prior to surgery and underwent cochlear implantation via a cochleostomy with a silastic-platinum dummy electrode. Pure tone auditory brainstem response (ABR) thresholds from 2 to 32 kHz were recorded prior to surgery, and at one and four weeks postoperatively. The cochleae were then fixed in paraformaldehyde, decalcified, paraffin embedded, and mid-modiolar sections were prepared. The treatment groups were as follows: 1) Systemic dexamethasone, 0.2 mg/kg administered 1 h before implantation, 2) Local dexamethasone, 2% applied topically to the round window for 30 min prior to cochlear implantation, 3) Local n-acetyl cysteine, 200 µg applied topically to the round window for 30 min prior to implantation, 4) inoculation to keyhole-limpet hemocyanin (KLH) prior to implantation, and 5) untreated controls. There was a significant correlation between the extent of the tissue reaction in the cochlea and the presence of foreign body giant cells (FBGCs), new bone formation and injury to the osseous spiral lamina (OSL). The extent of the tissue response, as a percentage of the area of the scala tympani, limited the best hearing that was observed four weeks after cochlear implantation. Poorer hearing at four weeks correlated with a more extensive tissue response, lower outer hair cell (OHC) counts and OSL injury in the basal turn. Progressive hearing loss was also correlated with the extent of tissue response. Hearing at 2 kHz, which corresponds to the region of the second cochlear turn, did not correspond with loco-regional inner hair cell (IHC), OHC or SGC counts. We conclude that cochlear injury is associated with poorer hearing early after implantation. The tissue response is related to indices of cochlear inflammation and injury. An extensive tissue response limits hearing at four weeks, and correlates with progressive hearing loss. These latter effects may be due to inflammation, but would also be consistent with interference of cochlear mechanics.

Biofilm formation on bone-anchored hearing aids.

OBJECTIVE: To investigate microbiological biofilm contamination of retrieved bone-anchored hearing aids. MATERIALS AND METHODS: Nine failed, retrieved bone-anchored hearing aids and 16 internal screws were examined by scanning electron microscopy. A fixture from a failing implant, which had been removed and disassembled under aseptic conditions, was cultured. Finally, an internal screw from a new, unimplanted fixture was examined by scanning electron microscopy. RESULTS: Debris was seen on the fixture and abutment of all bone-anchored hearing aids, and on the heads of the 16 internal screws. On eight screws, biofilm extended down the shaft to the threads, where it was several micrometres thick. Culture of a failing fixture yielded staphylococcus. The new, unimplanted fixture internal screw showed evidence of scratching and metallic debris on the threads, which may interfere with close fitting of the screw and subsequently facilitate microleakage. CONCLUSION: There may be a link between internal microbial contamination and failure of bone-anchored hearing aids.

Endovascular embolization of a traumatic arteriovenous fistula of the superficial temporal artery.

Arteriovenous fistula of the superficial temporal artery is a rare condition most commonly caused by trauma. Traditional surgical treatment has been superseded by endovascular embolization. We present the case of a 40 year-old man with a traumatic arteriovenous fistula of the superficial temporal artery who was treated by endovascular embolization. The advantages of this approach are discussed, along with a brief history of the condition.