Development and Validation of the Cochlear Implant Surgical Competency Assessment Instrument.

OBJECTIVE: We present a new instrument for evaluation of cochlear implant (CI) surgical skills and review its validation process. METHODS: An instrument to assess CI surgical competency incorporated results of structured surveys of comprehensiveness sent to 30 international CI experts and US trainees. One-hundred evaluations of 28 residents, fellows, and practicing CI surgeons were completed. Surgical skills were evaluated by four experienced neurotologists (two raters per subject) using two temporal bones per subject. A training session was completed by 24 subjects between the first and second procedure. Comparison of two blinded rater's scores per subject provided information on interrater reliability. Correlation of competency scores with degree of training and with improvement after a training session provided information on construct validity. RESULTS: High levels of interrater reliability were confirmed by using the intraclass correlation coefficient. Construct validity was demonstrated by correlation of higher performance scores with increasing years of training, board certification, and fellowship training. Construct validity is also supported by improvement in scores after a CI training session as well as by acceptability surveys. DISCUSSION: Data indicate that this instrument is an objective, accurate, and dependable procedure-specific instrument for evaluating CI surgical competency. CONCLUSION: The cochlear implant surgical competency assessment (CI-SCA) can be used to establish CI surgical competency, identify surgical skills that require remediation and demonstrate progress during training.

Acetaminophen and NAPQI are toxic to auditory cells via oxidative and endoplasmic reticulum stress-dependent pathways.

Pain relievers containing N-acetyl-para-aminophenol, also called APAP, acetaminophen or paracetamol, in combination with opioid narcotics are top-selling pharmaceuticals in the U.S. Individuals who abuse these drugs for as little as sixty days can develop tinnitus and progressive bilateral sensorineural hearing loss. Recently published studies indicate that APAP and its metabolic product N-acetyl-p-benzoquinoneimine (NAPQI) are the primary ototoxic agents in this type of pain relievers. However, the mechanisms underlying the deleterious effects of these drugs on auditory cells remain to be fully characterized. In this study, we report cellular, genomic, and proteomic experiments revealing that cytotoxicity by APAP and NAPQI involves two different pathways in Immortomouse-derived HEI-OC1 cells, implicating ROS overproduction, alterations in ER morphology, redistribution of intra-cisternal chaperones, activation of the eIF2α-CHOP pathway, as well as changes in ER stress and protein folding response markers. Thus, both oxidative and ER stress are part of the cellular and molecular mechanisms that contribute to the cytotoxic effects of APAP and NAPQI in these cells. We suggest that these in vitro findings should be taken into consideration when designing pharmacological strategies aimed at preventing the toxic effects of these drugs on the auditory system.

Dietary modification as adjunct treatment in Ménière's disease: patient willingness and ability to comply.

OBJECTIVE: To evaluate ease of use and compliance with dietary modification in the treatment of vertigo in patients with Ménière's disease. STUDY DESIGN: Mailed patient retrospective questionnaire and chart review. SETTING: Tertiary referral neurotologic private practice. SUBJECTS: 136 patients with Ménière's who returned a mailed questionnaire. Mean age at first clinic visit was 53 years, and at questionnaire was 62 years, with 54.4% female subjects. Median initial hearing was AAO-HNS Stage 1. Most patients also received diuretics and/or other treatments. INTERVENTION: Reduced sodium and caffeine-free diet. MAIN OUTCOME MEASURES: Ratings of diet difficulty, length of use, compliance level and nutritional understanding, and AAO-HNS vertigo class and functional rating before and with nutritional intervention. RESULTS: 46.3% of the respondents received written diet guidelines; only 3.2% were referred for nutritional counseling, and another 7.8% sought counseling independently. 77.8% and 84.7% rated a low sodium and a caffeine-free diet, respectively, as manageable or easy to follow; 77.9% followed the diet for 1 year or greater, but only 10.3% could list 5 "correct" foods to eat and 26% 5 foods to avoid. Those who followed the diet greater than 6 months had larger improvement in number of spells and functional rating and a higher rate of Class A/B vertigo outcome (p ≤ 0.01, p = 0.012, and p = 0.038, respectively). Knowledge of foods to eat and avoid correlated with vertigo class (rho = -0.21, p ≤ 0.029 and rho = -0.26, p ≤ 0.01, respectively); the more foods correctly listed, the better the AAO-HNS class). CONCLUSION: Nutrition education by referral to a registered dietitian may improve outcomes in the medical treatment of Ménière's disease.

In vitro and in vivo models of drug ototoxicity: studying the mechanisms of a clinical problem.

INTRODUCTION: Drug ototoxicity represents one of the main preventable causes of deafness. Ototoxicity is a trait shared by aminoglycoside and macrolide antibiotics, antimalarial medications, loop diuretics, platinum-based chemotherapeutic agents, some NSAIDs and most recently described, acetaminophen when abused with narcotic medication. These medications are prescribed despite their side effects, which includes inner ear toxicity, because they are life-saving drugs or there is a lack of better treatment. AREAS COVERED: This review will discuss in vitro and in vivo models of ototoxicity highlighting recently published ototoxicity research. The reader will learn the strengths and limitations of different ototoxicity models and what molecular insights have been gained from their application. A better understanding of the cellular mechanisms of these ototoxins will help in the discovery of ways to prevent and treat hearing loss associated with ototoxic medications. EXPERT OPINION: There are benefits to both in vitro and in vivo models of ototoxicity. Research of a particular medication and its ototoxic mechanisms should draw from several models, enabling a better answer to the clinical question of prevention and treatment of inner ear drug toxicity.

Evaluation of a customized acoustical stimulus system in the treatment of chronic tinnitus.

OBJECTIVE: The purpose of this study is to evaluate the efficacy of a customized acoustical stimulus (Neuromonics) system in the treatment of chronic tinnitus. STUDY DESIGN: Multi-institutional prospective. SETTING: Nine U.S. Tertiary Otological referral centers; ambulatory. PATIENTS: Fifty-two adults with chronic tinnitus for a minimum of 6 months, with poor or no response to previous treatments, and not undergoing concomitant therapies were enrolled. INTERVENTIONS: Treatment was delivered in 2 stages: Stage 1 consisted of stimulation with the patient-customized musical tracks and white noise masking of the tinnitus for 2 months, 2 to 4 hours a day. Stage 2 consisted of listening to the same tracks, with no tinnitus masking for 4 months. Both phases included education, cognitive therapy, and periodic follow-up. MAIN OUTCOME MEASURES: Treatment response was measured through validated psychometric testing: the Tinnitus Reaction Questionnaire and the Tinnitus Handicap Inventory. Other measures included the Hospital Anxiety Depression Scale and loudness discomfort levels. RESULTS: Patients' responses were recorded from 38 patients at 6 months, 28 patients at 12 months, and 12 patients at 24 months after initiation of treatment. A total of 14 patients withdrew or were lost to follow-up, and the rest had not reached the 12- or 24-month testing interval. The Tinnitus Reaction Questionnaire score was significantly reduced in 74% of patients at 12 months and 84% of patients at 24 months. Tinnitus Handicap Inventory scores were significantly reduced in 77% of patients at 12 months and 50% at 24 months. CONCLUSION: The customized acoustical stimulus system offers a safe and effective means of tinnitus management for patients with chronic tinnitus.

Acetaminophen ototoxicity after acetaminophen/hydrocodone abuse: evidence from two parallel in vitro mouse models.

OBJECTIVE: Acetaminophen/hydrocodone, a commonly used analgesic preparation, has been linked to rapidly progressing sensorineural hearing loss in human patients. The cellular and molecular mechanisms underlying the ototoxic effects of this drug combination are currently unknown, but are usually associated with high doses of hydrocodone. This study was aimed at identifying the specific agent responsible for hearing loss from toxic killing of cochlear sensory cells. STUDY DESIGN: Dose-response study. SETTING: University laboratory and private research facility. SUBJECTS AND METHODS: Math1 green fluorescent protein neonatal mouse cochlear cultures as well as a mouse auditory cell line (HEI-OC1) were exposed in vitro to different concentrations of acetaminophen, hydromorphone (the active metabolite of hydrocodone), and the micronutrient L-carnitine, either alone or combined. Using fluorescent and light microscopy, we quantified the sensory hair cells from a 600-microm basal segment before and after treatment. Acetaminophen/hydrocodone-induced apoptosis of HEI-OC1 was evaluated by caspase 3-activation studies. Statistically significant cell survival was determined with Student t test and analysis of variance. RESULTS: Cell death was associated mainly with exposure to acetaminophen, was slightly potentiated when combined with hydromorphone, and was partially prevented by L-carnitine. Exposure to hydrocodone or hydromorphone alone failed to kill either cochlear hair cells or HEI-OC1 cells. CONCLUSION: Our findings point to acetaminophen, rather than hydrocodone, as the primary cytotoxic agent. Hydrocodone, however, may work synergistically with acetaminophen, increasing the damage to auditory cells. These findings are an important first step toward understanding the mechanism of acetaminophen/hydrocodone ototoxicity and may lead to future treatment strategies for hearing loss from ototoxic medications.

Single vertical incision for Baha implant surgery: preliminary results.

OBJECTIVES: A single vertical skin incision with subcutaneous tissue removal is a cosmetic alternative for Baha implant placement. We aimed to determine the preliminary complication rate using a 4-cm vertical skin incision. STUDY DESIGN: Retrospective review. SUBJECTS AND METHODS: Vertical incision Baha implant placements from January 2006 to August 2007 were reviewed. Complications including skin irritation, skin overgrowth, and implant extrusion were tallied. A total of 71 patients underwent surgery, with a mean follow-up time of 7 months. RESULTS: There were five minor complications (three cases of skin irritation, one wound infection requiring oral antibiotics, one postoperative hematoma) and seven major complications (one case of irritation requiring abutment removal, six cases of skin overgrowth or infection requiring flap revision), for a total complication rate of 16.9 percent. CONCLUSIONS: A single vertical incision for Baha implant placement has a complication rate similar to that of traditional dermatome use in this preliminary study. Patients with thick scalps or risk factors for hypertrophic scarring may require longer abutments.

Recent experience with the neuromonics tinnitus treatment.

This study examines the outcomes of patients undergoing the Neuromonics tinnitus treatment protocol at a single, tertiary referral center over a 2-year period. A retrospective review of patient records was performed with the objective of collecting demographic and au-diological information and identifying changes in score on an established tinnitus questionnaire (Tinnitus Reaction Questionnaire [TRQ]) after treatment. Forty-seven patients initiated reatment with the Neuromonics device during the study period. Fourteen patients completed treatment, and another 18 were actively undergoing treatment at the end of the study period. The mean pure-tone average for the study group (N = 47) was 23.4 dB for the involved ear. Of those who completed the treatment, the mean posttreatment TRQ score was significantly lower than the pretreatment score (p approximately .001). Fifteen patients (31.9%) returned the device or did not complete treatment. Across all 47 patients, 48.9% achieved a successful reduction of 40% or greater in TRQ score. There was no correlation among pure-tone average, initial TRQ score or duration of use, and percentage change in TRQ score for those with at least one follow-up test. Based on these preliminary findings, treatment with the Neuromonics device is successful in reducing TRQ scores in appropriately selected patients with tinnitus.

Cochlear and brainstem implantation. 2002.

Cochlear and auditory brainstem implants offer safe and effective hearing habilitation and rehabilitation for profoundly deafened adults and children. Brainstem implant technology is currently approved for use in patients with type 2 Neurofibromatosis, who have lost integrity of auditory nerves following vestibular schwannoma removal. An update on implant devices, speech processing strategies, candidacy criteria, and perceptual performance are provided in this article.

Revision cochlear implant surgery in children.

OBJECTIVE: To determine the incidence of revision cochlear implant (CI) surgery in children and the indications for revision surgery and to examine the pattern of events that lead to revision CI surgery. STUDY DESIGN: Retrospective case review. SETTING: Two tertiary pediatric CI centers. PATIENTS: Pediatric CI patients who underwent revision surgery related to their CI. MAIN OUTCOME MEASURES: Reasons for revision, surgical outcomes, complications, performance, and device analyses were sought. RESULTS: Nine hundred fifty-two pediatric CI operations were performed between 1991 and 2005. Ninety-three patients underwent 107 (11.2%) revision operations. Hard device failure occurred in 46% (n = 49); soft failure occurred in 15% (n = 16); medical/surgical causes were responsible for 37% (n = 40); and magnet dislodgement requiring revision surgery occurred in 2% (n = 2). Head trauma was associated with 41% of the hard failure cases (n = 20). Device analyses revealed identifiable abnormalities in most of both hard and soft failure cases. In most patients, auditory performance equaled or surpassed the best preoperative performance by 6 to 12 months after revision. CONCLUSION: Revision CI surgery is common among pediatric CI recipients. Hard failure is the most common reason for undertaking revision surgery, and this mode of failure is frequently associated with preceding head trauma. Patients and parents should be counseled that performance is expected to equal or surpass the child's best level of performance before revision surgery, although this may take some time, and exceptions do exist.

Evaluation of facial function with a questionnaire: reliability and validity.

OBJECTIVES: To analyze the validity and reliability of assigning House-Brackmann facial nerve grade based on a patient-administered questionnaire. Specifically, the use of a questionnaire was studied for evaluation of the long-term facial function after microsurgical resection of vestibular schwannoma (VS). STUDY DESIGN: Three neurotologists with more than 25 years of experience and 3 neurotology clinical fellows rated facial nerve grade in a blinded fashion based on the questionnaire. The standard to which the questionnaires were compared was the facial nerve grade assigned to the patient during an office visit near the same time as the completed patient questionnaire. METHODS: Thirty-four patients had an office evaluation of facial function at least 1 year after microsurgical resection of a VS. Thirty patients had a sporadic VS, whereas 4 patients had neurofibromatosis 2. The average tumor size was 2.2 cm. A postoperative questionnaire regarding facial function was completed within 2 months of the office evaluation. Statistical analyses were performed to compare the office evaluation rating with the questionnaire rating (validity) and to analyze interobserver reliability. RESULTS: The association between the facial nerve grade assigned by the office evaluation and the questionnaire was highly significant (p<0.01), with a mean correlation (Spearman [rho]) equal to 0.94. The interobserver reliability was high, with coefficients ranging from 0.93 to 0.99 (p<0.01; mean=0.97). Because a large proportion of patients had normal (House-Brackmann Grade I) facial function, an additional analysis was performed with these patients excluded. The high levels of interobserver reliability persisted (average=0.96). CONCLUSION: When compared with office evaluation, a patient-administered questionnaire provides a valid and reliable measure of long-term facial function after VS surgery.

Nucleus Freedom North American clinical trial.

OBJECTIVE: To evaluate hearing outcomes and effects of stimulation rate on performance with the Nucleus Freedom cochlear implant (Cochlear Americas, Denver, CO). STUDY DESIGN AND SETTING: Randomized, controlled, prospective, single-blind clinical study using single-subject repeated measures (A-B-A-B) design at 14 academic centers in the United States and Canada and comparison with outcomes of a prior device by the same manufacturer. PATIENTS: Seventy-one severely/profoundly hearing impaired adults. RESULTS: Seventy-one adult recipients were randomly programmed in two different sets of rate: ACE or higher rate ACE RE. Mean scores for Consonant Nucleus Consonant words is 57%, Hearing in Noise Test (HINT) sentences in quiet 78%, and HINT sentences in noise 64%. Sixty-seven percent of subjects preferred slower rates of stimulation, and performance did not improve with higher rates of stimulation using this device. CONCLUSIONS: Subjects performed well, and there was no advantage to higher stimulation rates with this device. SIGNIFICANCE: Higher stimulation rates do not necessarily result in improved performance.

Clinical performance of children following revision surgery for a cochlear implant.

OBJECTIVES: The purpose of this study was to describe the causes for revision surgery and to compare clinical performance before and after surgery in children who required electrode reinsertion. STUDY DESIGN AND SETTINGS: Soundfield thresholds and speech recognition scores were compared before device failure and following electrode reinsertion. Temporal bones from a deceased adult implant user who underwent bilateral revision implantation were analyzed. RESULTS: Histopathology in the adult temporal bones revealed new bone formation in the scala tympani and substantially reduced spiral ganglion counts, with open-set speech recognition realized. Of 28 children undergoing revision surgery, 18 required electrode reinsertion. With the exception of 1 patient with severe cochlear malformation, new electrode arrays were fully inserted without difficulty. Clinical outcomes between pre-device failure and post-electrode reinsertion did not differ statistically. CONCLUSION AND SIGNIFICANCE: Electrode reinsertion is technically feasible in the pediatric population. The majority of children recover their prerevision clinical performance. EBM RATING: C-4.

A temporal bone study of insertion trauma and intracochlear position of cochlear implant electrodes. I: Comparison of Nucleus banded and Nucleus Contour electrodes.

In recent years, new designs of cochlear implant electrodes have been introduced in an attempt to improve efficiency and performance by locating stimulation sites closer to spiral ganglion neurons and deeper into the scala tympani. The goal of this study was to document insertion depth, intracochlear position and insertion trauma with the Nucleus Contour electrode and to compare results to those observed with the earlier generation Nucleus banded electrode. For this comparison eight Nuclears banded electrodes and 18 Contour electrodes were implanted in cadaver temporal bones using a realistic surgical exposure. Two experienced cochlear implant surgeons and two otology fellows with specialized training in cochlear implant surgery were selected for the study to represent a range of surgical experience similar to that of surgeons currently performing the procedure throughout the world. Following insertion of the electrodes, specimens were imaged using plain film X-ray, embedded in acrylic resin, cut in radial sections with the electrodes in place, and each cut surface was polished. Insertion depth was measured in digitized X-ray images, and trauma was assessed in each cross-section. The Contour electrode inserted more deeply (mean depth=17.9 mm or 417 degrees ) than the banded electrode (mean depth=15.3 mm or 285 degrees ). The incidence and severity of trauma varied substantially among the temporal bones studied. However, the nature and frequency of injuries observed with the two devices were very similar. The Contour electrode was clearly positioned closer to the modiolus than the banded model, and also appeared easier to use. Based on this difference in position and data from previous studies we conclude that the Contour electrode may provide lower thresholds and improved channel selectivity, but the incidence of trauma remains a problem with the newer design. The relative influences of electrode positioning and neural degeneration that may result from trauma are as yet unclear.

A temporal bone study of insertion trauma and intracochlear position of cochlear implant electrodes. II: Comparison of Spiral Clarion and HiFocus II electrodes.

In recent years, several new designs of cochlear implant electrodes have been introduced clinically with the goal of optimizing perimodiolar placement of stimulation sites. Previous studies suggest that perimodiolar electrodes may increase both the efficiency and performance of a cochlear implant. This is the second of two studies designed to examine the positioning of electrodes and the occurrence of insertion-related injury with these newer designs and to directly compare two perimodiolar electrodes to their predecessors. In our previous report we compared the Nucleus banded electrode with the Nucleus Contour perimodiolar electrode. In the present study, using the same protocol, we examine the Spiral Clarion electrode and its successor, the HiFocus II electrode with attached positioner. Eight Spiral Clarion arrays and 20 HiFocus II electrodes with positioners were inserted into human cadaver temporal bones. Following insertion, the specimens were embedded in acrylic resin, cut in quarters with a diamond saw and polished. Insertion depth, proximity to the modiolus and trauma were evaluated in X-ray images and light microscopy. The newer electrode was consistently positioned closer to the modiolus than the previous device whereas the angular depth of insertion measured for the two electrodes was similar. The incidence of trauma was minimal when either electrode was inserted to a depth of less than 400 degrees . However, severe trauma was observed in every case in which the HiFocus II with positioner was inserted beyond 400 degrees and in some cases in which the Spiral Clarion was inserted beyond 400 degrees . To evaluate the possible role of electrode size in the trauma observed we modeled both devices relative to the dimensions of the scala tympani. We found that the fully inserted HiFocus II electrode with positioner was larger than the scala tympani in approximately 70% of temporal bones measured. The results suggest that both the Clarion spiral and HiFocus II with positioner can be inserted with minimal trauma, but in many cases not to the maximum depth allowed by the design.

Surgical outcomes in patients with endolymphatic sac tumors.

OBJECTIVE: To determine the surgical outcomes in patients with endolymphatic sac tumors (ELSTs). STUDY DESIGN: Retrospective review of patients at a referral-based otology-neurotology practice. METHODS: A review of the records from the House Ear Clinic revealed 16 patients treated for ELSTs from 1971 to 2002. This article reports the treatment outcomes for the 14 patients for whom clinical data were available. RESULTS: Sensorineural hearing loss, tinnitus, and dizziness were the most common presenting signs and symptoms. Six patients presented with facial weakness, and three patients had symptoms characteristic of Menière's syndrome. One patient suffered from Von Hippel-Lindau disease. Patients underwent microsurgical removal and were followed for an average of 59.6 months. Patients that presented with normal facial function maintained excellent postoperative function, and hearing was preserved in two patients with small tumors. Two patients suffered persistent, progressive disease despite multiple attempts at microsurgical removal and radiotherapy. Both had incomplete resections of their initial tumors. A third patient developed a small recurrent tumor that was successfully managed by a second attempt at microsurgical removal. CONCLUSIONS: Taken together with other reports, these results suggest that ELSTs are best managed by complete surgical resection. This can generally be accomplished with minimal additional morbidity.

Postoperative infection in cochlear implant patients.

OBJECTIVE: Recently, the association of meningitis with cochlear implants has raised concern over the safety of these devices. We examined the incidence of all postoperative infections in patients undergoing cochlear implant surgery. Study design and settings A retrospective chart review of all patients undergoing cochlear implants at a private tertiary referral center from 1993 to 2002 was performed. Cochlear implant surgeries in 462 adults and 271 children were reviewed. Patients with evidence of a postoperative infection or infectious complication related to cochlear implantation were identified, and data on patient characteristics, surgery, and treatment outcome were obtained. RESULTS: The overall incidence of postoperative infection in our cochlear implant series was 4.1%. Major infectious complications occurred in 3.0% of cases, and the majority of infections required surgical intervention. A history of chronic ear disease may increase the risk of infectious complications. There were no cases of meningitis. CONCLUSIONS: Cochlear implants remain a safe procedure with a low complication rate. The majority of infections can be managed without removing the implant device. Advances in surgical technique and flap design have decreased the occurrence of wound-related complications. However, identification of risk factors for infection and optimization of treatment regimens will further reduce the complications associated with postoperative infection.

Management of cholesteatoma: status of the canal wall.

OBJECTIVE/HYPOTHESIS: Management of chronic otitis media with cholesteatoma remains controversial. The purpose of the study is to examine factors associated with the surgical approach to manage cholesteatoma. STUDY DESIGN: A retrospective review. METHODS: A retrospective review was made of all primary cases of mastoid surgery for cholesteatoma performed at an otological center between 1995 and 2000. During the study period, 486 ears underwent surgery for cholesteatoma. Data included procedures performed, location and extent of the disease, residual and recurrent disease, complications, reasons for staging the surgery, and duration of follow-up. RESULTS: The canal wall remained intact in 68.5% of ears. The majority of the remainder of the patients underwent a canal wall down technique with mastoid obliteration. Residual cholesteatoma was found in 26.9% of second procedures and in 2.7% of third procedures. CONCLUSIONS: The majority of patients with cholesteatoma can be adequately managed with a canal intact tympanomastoidectomy with staging. Otolaryngologists should consider a two-staged procedure as a viable management approach for chronic otitis media with cholesteatoma.

Cochlear and brainstem implantation.

Cochlear implantation is an established habilitative and rehabilitative option for profoundly deafened individuals over 1 year of age who derive limited benefit from conventional hearing aids. Auditory performance varies among individuals and is determined primarily by age at implantation, pre-existence of speech and language skills, and the time interval between onset of deafness and implantation. Successful implant users generally demonstrate improved auditory abilities and speech production skills beyond those achieved with hearing aids. Multichannel ABIs can provide useful auditory information to patients with NF-2 who have lost integrity of auditory nerves following removal of vestibular schwannomas. The implant allows for awareness of environmental sounds and, potentially, speech recognition. Most patients undergoing implantation demonstrate improved lip-reading skills, and exceptional performers achieve understanding of open-set speech.