Corrigendum to "The Effect of Cochlear Size on Cochlear Implantation Outcomes".

[This corrects the article DOI: 10.1155/2019/5849871.].

Otology/Neurotology recommendations - Choosing Wisely campaign.

The Choosing Wisely Canada Campaign aims to raise awareness amongst physicians and patients regarding unnecessary tests and treatment. The otology/neurotology subspecialty group within the Canadian Society of Otolaryngology - Head & Neck Society developed a list of five common otologic presentations to help physicians deliver high quality effective care: (1) Don't order specialized audiometric and vestibular testing to screen for peripheral vestibular disease, (2) Don't perform computed tomography or blood work in the evaluation of sudden sensorineural hearing loss, (3) Don't perform auditory brain responses (ABR) in patients with asymmetrical hearing loss, (4) Don't prescribe oral antibiotics as first line treatment for patients with painless otorrhea associated with tympanic membrane perforation or tympanostomy tube, and (5) Don't perform particle repositioning maneuvers without a clinical diagnosis of posterior canal benign paroxysmal positional vertigo.

The Effect of Cochlear Size on Cochlear Implantation Outcomes.

OBJECTIVES: To determine if cochlear duct length and cochlear basal diameter, measured using routinely available radiology software, affect hearing outcomes after cochlear implantation with two different length electrodes. METHODS: 55 patients who received a Med-El Flex electrode were retrospectively reviewed. 34 patients received the Flex 31 electrode (31mm) and 21 patients received the Flex 28 electrode (28mm). Preoperative high-resolution CT scans of the temporal bone were reformatted in the axial and coronal plane. The basal diameter of the cochlear (A-value) and the outer-wall lengths of the cochlear duct were measured using readily available imaging software. Postoperative plane X-rays were used to determine the degree of electrode insertion and the number of electrodes within the cochlea and speech discrimination scores at 6 months were evaluated. RESULTS: The cochlear metrics obtained were comparable with those previously published in the literature. There was no significant difference in the degree of insertion or speech outcomes between the two electrode lengths. However, when the group who had received the shorter electrode were analysed, there was an association seen between both cochlear duct length and cochlear diameter and speech outcomes. CONCLUSIONS: Cochlear size may be a factor in determining speech outcomes that cannot be explained solely by insertion depth or degrees of insertion. Further studies are required to determine if cochlear duct length is an independent predictor of speech outcomes.

The Benefit of a Wireless Contralateral Routing of Signals (CROS) Microphone in Unilateral Cochlear Implant Recipients.

OBJECTIVE: Assess speech outcomes in unilateral cochlear implant (CI) recipients after addition of a wireless contralateral routing of signals (CROS) microphone. STUDY DESIGN: Prospective cohort study. SETTING: Ambulatory. PATIENTS: Sixteen adult unilateral CI users with nonserviceable hearing on the contralateral side were recruited. Those with AzBio sentence scores of 40 to 80% or Hearing in Noise Test - Quiet (HINT-Q) scores of 60 to 90% with a CI alone were eligible participants. INTERVENTION: Speech testing was carried out with the CROS on and off. MAIN OUTCOME MEASURE: Speech recognition. RESULTS: In the consonant-nucleus-consonant test presented in quiet from the front, word scores were 64.4 (CI) and 63.8% (CI + CROS) (p = 0.72), and phoneme scores were 80.2 (CI) and 80.8% (CI + CROS) (p = 0.65). In AzBio sentence testing in quiet, with the signals projected from the contralateral, front, or ipsilateral to the CI, speech perception with the CI alone was 60.8, 75.9, and 79.1%. With the addition of the CROS microphone, using the same speaker arrangement, speech perception was 69.8 (p < 0.05), 71.8 (p = 0.05), and 71.8 (p < 0.05). In AzBio sentence testing in noise, speech perception with the CI alone was 18.6, 45.3, and 56.3% when signals were projected from contralateral, front, and ipsilateral sides to the CI. The addition of the CROS microphone led to speech perception of 45.3 (p < 0.05), 45.3 (p = 0.86), and 51.4% (p = 0.27) in the same paradigm. CONCLUSIONS: Addition of a wireless CROS microphone to a unilateral CI recipient can improve users' perception of speech in both quiet and noise if speech signals come from the deaf ear, mitigating the head shadow effect.

Isolated Second Implant Adaptation Period in Sequential Cochlear Implantation in Adults.

OBJECTIVE: To determine if depriving the use of the first cochlear implant (CI1) impacts adaptation to a sequential implant (CI2). STUDY DESIGN: Prospective cohort. SETTING: Academic center. PATIENTS: Sixteen unilateral cochlear implant recipients undergoing contralateral implantation (sequential bilateral) were matched according to age, etiology, duration of deafness, device age, and delay between implants. INTERVENTION: During a 4-week adaptation period after CI2 activation, patients underwent deprivation of CI1 or were permitted continued use of it. MAIN OUTCOME MEASURES: Speech perception scores and subjective quality of life outcomes before CI2 and at 1, 3, 6, and 12-months following activation. RESULTS: Maximal CI2 speech perception scores in quiet were achieved by 1-month postactivation for the "deprivation" group (71.3% for hearing in noise test [HINT], p = 0.767 for change beyond 1-mo) compared with 6-months for the "continued use" group (67.9% for HINT, p = 0.064 for change beyond 6-mo). The "deprivation" group experienced a temporary drop in CI1 scores (67.9% for HINT in quiet at 1-mo versus 78.4% pre-CI2, p = 0.009) recovering to 77.3% by 3-months; unchanged from baseline levels (p = 1.0). A binaural advantage over the better hearing ear was present for HINT sentences with noise (72.4% versus 58.8% for "deprivation", p = 0.001; 71.5% versus 52.7% for "continued use," p = 0.01). Missing data precluded a meaningful analysis of subjective quality of life outcome scales. CONCLUSION: Bilateral cochlear implantation improves speech perception compared with one implant. A period of deprivation from CI1 shortens time to maximum speech perception by CI2 without long-term consequences on the performance of CI1.

The Role of Preoperative Steroids for Hearing Preservation Cochlear Implantation: Results of a Randomized Controlled Trial.

OBJECTIVES: To determine whether preoperative steroids can improve hearing outcomes in cochlear implantation (CI). METHODS: This is a randomized controlled trial involving 30 postlingual deaf CI patients. Subjects had preoperative thresholds of better than or equal to 80 dB at 125 and 250 Hz, and better than or equal to 90 dB at 500 and 1,000 Hz. The subjects were randomized to a control group, an oral steroid group (receiving 1 mg/kg/day of prednisolone for 6 days prior to surgery), or a transtympanic steroid group (receiving a single dose of 0.5 mL of 10 mg/mL dexamethasone at 24 h prior to surgery). RESULTS: The subjects receiving transtympanic steroids had a significant decrease in the pure tone average over 3 months compared to the control and oral steroid group, which persisted over 12 months (p < 0.05). CONCLUSION: A single dose of preoperative transtympanic steroids prior to CI appears to have a beneficial effect, at least in the short term, with minimal effects seen in the longer term.

Depth of Cochlear Implant Array Within the Cochlea and Performance Outcome.

OBJECTIVE: To evaluate whether the depth of cochlear implant array within the cochlea affects performance outcomes 1 year following cochlear implantation. METHODS: A retrospective case review of 120 patients who were implanted with the Advanced Bionics HiFocus 1J. Post-implantation plain-radiographs were retrospectively reviewed, and the depth of insertion was measured in degrees from the round window to the electrode tip. Correlation between the depth of insertion and 1-year post-activation Hearing in Noise Test (HINT) scores was analyzed. Intrascala position was not assessed. RESULTS: Depth of electrode insertion ranged from 180° to 720°, and HINT scores ranged from 0% to 100%. A Mann-Whitney U test demonstrated significantly improved 1-year post-activation HINT scores in patients with an insertion depth of 360° or more in comparison with patients with insertion depth of less than 360° (81% vs 61%, P = .048). Patients with 13 to 15 contacts within cochlear turns performed as well as patients with full insertion of all 16 contacts, while patients with only 12 contacts performed poorly. CONCLUSIONS: Insertion depth of the AB HiFocus 1J electrode of less than 360° is associated with reduced 1-year post-activation HINT scores when compared with deeper insertions. Partial insertion of 13 active contacts or more led to similar results as full insertion.

Assessment of the psychosocial impacts of cochlear implants on adult recipients and their partners.

OBJECTIVES: In the present study we sought to evaluate the psychosocial and quality of life (QOL) impacts of cochlear implant (CI) treatment on both CI recipients and their partners in a Canadian population. METHODS: A qualitative cross-sectional contemporary cohort evaluation was conducted by distributing specifically designed questionnaires to both CI recipients and their partners at their follow-up appointments over a month at Sunnybrook Health Sciences Centre. RESULTS: It was found that both CI recipients and their partners demonstrated substantial benefit and improvement in multiple psychosocial domains. DISCUSSION: Musical listening was found to show variable improvements between recipients. Further analysis found a simple correlation where the group of recipients who all had a hearing disability for a longer duration had demonstrated a higher proportion of improvement in musical listening. CI recipients endorsed having improved QOL which was in agreement with proxy observation by partners. CONCLUSION: Overall, CI use has been shown to have significant benefit to psychosocial well-being of CI recipients. This benefit is also conferred to their caregivers/partners; which in our society concerned about caregiver burden is quite important to recognize.

The role of extended preoperative steroids in hearing preservation cochlear implantation.

INTRODUCTION: Steroids have been shown to reduce the hearing threshold shifts associated with cochlear implantation. Previous studies have examined only the administration of steroids just prior to surgery. The aim of this study is to examine the role of extended preoperative systemic steroids in hearing preservation cochlear implantation. METHODS: An animal model of cochlear implantation was used. 24 Hartley strain guinea pigs with a mean weight of 768 g and normal hearing were randomised into a control group, a second group receiving a single dose of systemic dexamethasone one day prior to surgery, and a third group receiving a daily dose of systemic dexamethasone for 5 days prior to surgery. A specially designed cochlear implant electrode by Med-EL (Innsbruck) was inserted through a dorsolateral approach to an insertion depth of 5 mm and left in-situ. Auditory brain stem responses at 8 kHz, 16 kHz and 32 kHz were measured preoperatively, and 1 week, 1 month and 2 months postoperatively. Cochlear histopathology was examined at the conclusion of the study. RESULTS: At 1-week post operative, both groups receiving dexamethasone prior to implantation had smaller threshold shifts across all frequencies and which was significant at 32 kHz (p < 0.05). There were no differences among the three groups in the area of electrode related fibrosis. Spiral ganglion neuron (SGN) density was significantly higher in the group receiving steroids for 5 days, but only in the basal cochlear turn. DISCUSSION: This is study demonstrates the benefits of extended preoperative systemic steroids on hearing outcomes and SGN density in an animal model of cochlear implantation surgery.

Predictors of round window accessibility for adult cochlear implantation based on pre-operative CT scan: a prospective observational study.

BACKGROUND: Cochlear implantation has become a mainstream treatment option for patients with severe to profound sensorineural hearing loss. During cochlear implant, there are key surgical steps which are influenced by anatomical variations between each patient. The aim of this study is to determine if there are potential predictors of difficulties that may be encountered during the cortical mastoidectomy, facial recess approach and round window access in cochlear implant surgery based upon pre-operative temporal bone CT scan. METHODS: Fifty seven patients undergoing unilateral cochlear implantation were analyzed. Difficulty with 1) cortical mastoidectomy, 2) facial recess approach, and 3) round window access were scored intra-operatively by the surgeon in a blinded fashion (1 = "easy", 2 = "moderate", 3 = "difficult"). Pre-operative temporal bone CT scans were analyzed for 1) degree of mastoid aeration; 2) location of the sigmoid sinus; 3) height of the tegmen; 4) the presence of air cells in the facial recess, and 5) degree of round window bony overhang. RESULTS: Poor mastoid aeration and lower tegmen position, but not the location of sigmoid sinus, are associated with greater difficulty with the cortical mastoidectomy. Presence of an air cell around the facial nerve was predictive of easier facial recess access. However, the degree of round window bony overhang was not predictive of difficulty associated with round window access. CONCLUSION: Certain parameters on the pre-operative temporal bone CT scan may be useful in predicting potential difficulties encountered during the key steps involved in cochlear implant surgery.

The role of a new contralateral routing of signal microphone in established unilateral cochlear implant recipients.

OBJECTIVES/HYPOTHESIS: To investigate whether a contralateral routing of signal (CROS) microphone combined with a unilateral cochlear implant (CI) results in hearing improvement after a prolonged trial period. STUDY DESIGN: A prospective experimental trial was undertaken on a group of 10 postlingually deafened adults who are experienced CI users. METHODS: Participants completed audiometric testing and validated questionnaires with their unilateral CI alone, followed by addition of a CROS microphone (CI-CROS). This was worn daily for the 2-week trial, after which hearing performance was reevaluated using the same measures. Objective tests included AzBio sentences in quiet and noise and consonant-vowel nucleus-consonant (CNC) words. Subjective measures included the Abbreviated Profile of Hearing Aid Benefit (APHAB); Speech, Spatial, Qualities of Hearing Index (SSQ); Hearing Implant Sound Quality Index; an institutional questionnaire; and a daily log sheet. RESULTS: There is statistically significant enhanced speech discrimination with the CI-CROS when speech is presented on the CROS side. However, scores are markedly diminished when background noise is introduced, particularly to the CROS side. Subjective results indicate lower satisfaction scores for the global and ease of communication subdomains of the APHAB with the CI-CROS, but increased scores on the spatial hearing subdomain of the SSQ (P < 0.05). CONCLUSION: The CI-CROS provides significant benefit in certain situations, particularly speech recognition in quiet. CI-CROS performance with background noise is poor, leading to low satisfaction scores. Further refinement of the device may yield a useful tool for unilateral CI users in the future.

Cochlear implantation in patients with chronic suppurative otitis media.

OBJECTIVE: To determine the safety, efficacy, and outcomes of cochlear implantation in patients with chronic suppurative otitis media (CSOM). STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center with large cochlear implant program. PATIENTS: Nineteen patients with CSOM who underwent cochlear implantation were identified. Case history, timing of surgical procedures, complications, infections, and postimplant audiometric scores (Hearing in Noise Test [HINT], City University of New York Sentences [CUNY], and Central Institute for the Deaf Sentences [CID]) were evaluated. MAIN OUTCOME MEASURES: Rates of postoperative infections and complications as well as postimplant auditory performance. RESULTS: Twelve patients underwent a staged procedure involving canal wall down mastoidectomy or radical revision mastoidectomy with middle ear and mastoid obliteration and closure of the external auditory canal followed by cochlear implantation approximately 5 months later. Seven patients were implanted in a single procedure. There were no infections or medical complications after implantation. On average, patients had excellent audiometric scores at 1 year postimplantation (mean sentence test, 79%; SD, 14), and these scores were comparable to our general population (mean sentence test, 71%; SD, 32). CONCLUSION: Cochlear implant patients with CSOM have no increased risk of postoperative infections or complications. These patients have excellent outcomes with audiometric scores comparable to the general cochlear implant population. Cochlear implantation is a safe and effective treatment for patients with profound hearing loss secondary to CSOM.

Hearing preservation with full insertion of the FLEXsoft electrode.

OBJECTIVES: Hearing preservation (HP) in the context of cochlear implantation (CI) is indicative of an atraumatic insertion, which could potentially offer a clinical advantage to performance, whether such preservation was intended for the application of electoacoustic stimulation (EAS). Our goal was to determine the degree of HP after the implantation of a full-length electrode array (MedEl FLEXsoft). STUDY DESIGN: Prospective, within-subject repeated measure design. METHODS: Adult patients with residual low-frequency hearing who received a 31.5-mm FlexSoft electrode array were included. Implantation using soft surgery techniques occurred at a single tertiary referral center between 2008 and 2011. Preoperative and postoperative audiometric data were compared. RESULTS: In 36 consecutive patients at 1 year postimplantation, 6 (21%) maintained complete HP (an increase of low-frequency pure-tone average (PTA) ≤10 dB from the preoperative value), and 19 (65%) maintained partial HP (an increase in low-frequency PTA ≤40 dB from the preoperative values) throughout the follow-up period (average, 368 d). Higher preoperative hearing threshold levels (HTLs) at 1,000 Hz were associated with HP. CONCLUSION: Low-frequency HP is possible in patients implanted with the full-length FlexSoft electrode. Longer follow-up is required to determine if results are maintained over time and if such preservation is in fact advantageous to clinical outcomes. LEVEL OF EVIDENCE: 4.

Ten-year health-related quality of life in cochlear implant recipients: prospective SF-36 data with SF-6D conversion.

OBJECTIVES/HYPOTHESIS: To evaluate the long-term impact of cochlear implantation on quality of life measured by the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Scores were also converted to the SF-6D to derive health utility scores. STUDY DESIGN: Prospective cohort study. METHODS: Thirty-two patients undergoing cochlear implantation completed the SF-36 preoperatively, 1 year, and 10 years after cochlear implantation. RESULTS: SF-36 results showed improvements in seven of the eight attributes when preoperative scores where compared with 1- and 10-year results. Between 1 and 10 years postoperatively, six of eight domains deteriorated in scores. When converted to the SF-6D, the mean preoperative utility scores were 0.592 for standard gamble, 0.636 using the ordinal health state paradigm, and 0.579 using the Bayesian technique. Ten years postoperatively, health utility scores were 0.643 (standard gamble), 0.684 (ordinal health state), and 0.6 (Bayesian). Between preoperatively and 10-year postoperatively, improvements were therefore 0.051, 0.048, and 0.021 for standard gamble, ordinal health state, and Bayesian paradigm, respectively. CONCLUSIONS: This study establishes the long-term sustained benefits of cochlear implantation on quality of life. Nevertheless, both the SF-36 and SF-6D seem to underestimate the benefit accrued through this intervention. Our data are consistent with others regarding the unsuitability of the SF-36 in benefit assessment, notwithstanding that conversion to the SF-6D is feasible, and the SF-6D seemed to better depict possible benefits from cochlear implantation as compared to the SF-36.

Cochlear implantation in patients with advanced Ménière's disease.

BACKGROUND/OBJECTIVES: Ménière's disease (MD) that results in bilateral severe to profound sensorineural hearing loss is a rare indication for cochlear implantation; only a few studies exist documenting performance in these patients. The primary objective was to compare the difference in preoperative to 12-month postoperative speech perception scores among subjects with MD and controls. Groupwise comparisons of secondary postoperative outcomes (Tinnitus Handicap Inventory [THI] scores, 36-Item Short Form [SF-36] scores, and postoperative dizziness) were also performed. METHODS: A retrospective cohort study was conducted. Subjects with MD and controls matched by age, device manufacturer and model, preoperative sentence score, and sentence test used for preimplantation and postimplantation performance assessments were identified from 1,130 patients in the prospectively maintained cochlear implant database at our center. Speech perception, THI, and SF-36 scores and demographic variables were obtained from the database. Vestibular outcomes were obtained by retrospective chart review. Statistical comparisons were performed to compare preoperative to postoperative change between groups. RESULTS: Twenty patients with MD were identified. At 1 year after CI, improvements in sentence and word understanding did not differ in magnitude from the controls. Tinnitus was reduced significantly in patients with MD, whereas there was a trend for improvement in the controls. Quality of life as measured by the SF-36 improved in both groups. Patients with MD had significant improvements in 1 domain compared with 5 domains for the controls. Subjects with MD had significantly more chronic dizziness in the postoperative period than did controls. CONCLUSIONS: Patients with MD who have bilateral severe to profound sensorineural hearing loss benefit significantly from CI. Ongoing dizziness in some patients with MD may result in quality of life improvements that are slightly less than seen for the average adult patient with CI. Larger studies are needed to corroborate the results.

A late recognition of tapia syndrome: a case report and literature review.

Tapia syndrome is characterized by concurrent paralysis of the recurrent laryngeal and hypoglossal nerves. The mechanism is associated with airway manipulation in 70% of patients and is attributed to compression or stretching of these nerves. Diagnosis is based on recognition of the concurrent paralyses and investigations to exclude central or vascular causes. Treatment is supportive, with emphasis on empiric corticosteroids and dysphagia therapy. Recovery is excellent in 30% of patients, incomplete in 39% of patients, and none in over 26% of patients. A case of a 48-year-old woman is described, who was diagnosed with Tapia syndrome 3 years after the suspected injury.

Bilateral sequential adult cochlear implantation: who should receive priority in the context of a constrained health care system?

Resource allocation decisions have become increasingly necessary as the cost of health care habitually increases. Bilateral (second side) adult cochlear implantation (CI) is an example of a novel technology with accruing evidence of benefit, yet expense has limited universal employ. Currently at our centers, bilateral implantation is only provided under research protocol. In this article, we discuss the need for a principled approach concerning the distribution of a second device, both during this period of investigation and if ultimately an insured service. Allocation strategies, while extensively addressed in some arenas, have yet to be developed for second-side sequential adult CI. We advocate that physicians must assume an explicit role when both caring for individual patients as well as administering health care programs. We review social justice theories that inform resource allocation macrodecisions, and include a defence of age-based considerations. Our approach to patient selection for adult second-side CI sequentially considers clinical criteria (directly addressed in the article), a willingness to participate in rigorous research, and a 65 year cut-off. Ultimately, we employ random blinded selection for allocating bilateral CI among the remaining similarly situated individuals. This approach functions impartially and in a manner that is transparent for both patient and physician.

Dexamethasone uptake in the murine organ of Corti with transtympanic versus systemic administration.

OBJECTIVE: To investigate glucocorticoid uptake in auditory hair cells following transtympanic versus systemic administration of dexamethasone. STUDY DESIGN: Controlled experimental study. SETTING: Translational science experimental laboratory. METHODS: Swiss-Webster mice were injected with dexamethasone via transtympanic or systemic administration. At 1, 6, or 12 hours post-injection the temporal bones were harvested. After cryosectioning, immunohistochemical staining was performed using an antibody for dexamethasone. RESULTS: Dexamethasone labelling was greatest at 1 hour. Inner hair cells demonstrated much higher steroid uptake than outer hair cells. Both transtympanic injection and high-dose systemic administration resulted in strong dexamethasone labelling of hair cells, and a decreasing basal-to-apical gradient of hair cell fluorescence intensity was observed. Systemically delivered dexamethasone was rapidly eliminated from the inner ear, demonstrating mild labelling after 6 hours and none after 12 hours. In contrast, the mice receiving transtympanic injection had persistent moderate intensity fluorescence at 6 and 12 hours post-injection. CONCLUSION: There is similar uptake of dexamethasone by auditory hair cells after transtympanic and high-dose systemic delivery. Novel findings include the presence of a decreasing basal-apical gradient of steroid uptake, and demonstration of greater affinity of inner hair cells for dexamethasone compared to outer hair cells. In this animal model transtympanic injection resulted in prolonged steroid uptake. These findings help further our understanding of the pharmacokinetics of steroids in the cochlea, with a focus on auditory hair cells.