Risk of Stroke and Myocardial Infarction After Sudden Sensorineural Hearing Loss: A Meta-Analysis

OBJECTIVES/HYPOTHESIS

The pathophysiology of idiopathic sudden sensorineural hearing loss (ISSNHL) is still unknown, but labyrinthine artery infarction has been proposed. The objective of this study was to perform a systematic review and conduct a meta-analysis assessing the risk of developing stroke and myocardial infarction after presentation with ISSNHL.

METHODS

A systematic literature review was conducted using Pubmed, Embase, Web of Science, and Cochrane Libraries. All studies investigating an association between ISSNHL and stroke and/or myocardial infarction (MI) were included. Adhering to the MOOSE guideline, two independent reviewers extracted data, assessed risk of bias, and evaluated the relevance and quality of evidence.

RESULTS

Three observational studies evaluating the risk of stroke in ISSNHL were included (n = 6,521 patients). All individual study results indicated an increased relative risk of stroke after ISSNHL (unadjusted relative risk range 1.21-1.63). Pooled adjusted hazard ratios revealed a 1.42-fold increased risk of stroke after ISSNHL (hazard ratio [HR] 1.42; 95% confidence interval [CI] 1.15-1.75, I² = 55%). Subgroup analysis of one study demonstrated that the increased risk is only present in adults aged above 50 years (HR 1.23; 95% CI 1.07-1.42). Five observational studies evaluating the risk of MI in patients with ISSNHL were included (n = 61,499 patients). Pooled analyses demonstrated that ISSNHL was not associated with MI (HR 1.08, 95% CI 0.87-1.34).

CONCLUSION

ISSNHL may be an independent risk factor for the subsequent development of stroke especially in a subgroup of elderly patients. More studies are needed to confirm this association and to assess whether such patients would benefit from cardiovascular risk assessment and management to prevent future strokes. Laryngoscope, 131:1369-1377, 2021.

Use of auditory evoked potentials with electrical stimulation at the round window niche pre-operatively on a brain-injured patient: A case study

OBJECTIVES

To highlight the effectiveness of using PS testing in conjunction with electrically evoked auditory evoked potentials (eAEPs) to help guide treatment plans in patients with limited behavioural responses.

METHODS

Case report on a 59-year-old male with traumatic brain injury. Electrophysiological measurements in conjunction with PS were performed.

RESULTS

eAEPs were obtained up to the thalamo-cortical region, supporting the viability of a CI in the non-implanted ear.

DISCUSSION & CONCLUSION

Use of PS in conjunction with electrically evoked auditory evoked potentials can provide valuable information to guide clinical decisions regarding implantation.

Guidance for otolaryngology health care workers performing aerosol generating medical procedures during the COVID-19 pandemic

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for Coronavirus disease 2019 (COVID-19) has a predilection for infecting the mucosa of the upper and lower airways. Otolaryngologists and supporting health care workers (HCWs) are particularly at high risk of becoming infected while treating patients as many in-office procedures and surgeries are Aerosol Generating Medical Procedures (AGMP). Based on a review of the literature and various guidelines, recommendations are made to mitigate the risk to health care workers of becoming infected with SARS-CoV-2 while providing clinical care.

Recommendations

During the COVID-19 pandemic all elective and non-time sensitive Otolaryngology procedures should be deferred to mitigate the risk of transmission of infection to HCWs. For non-AGMPs in all patients, even COVID-19 positive patients Level 1 PPE (surgical mask, gown, gloves and face shield or goggles) is sufficient. If local prevalence is favourable and patients are asymptomatic and test negative for SARS-CoV-2, Level 1 PPE can be used during short duration AGMPs, with limited risk of infected aerosol spread. For AGMPs in patients who test positive for SARS-CoV-2 a minimum of Level 2 PPE, with adequate protection of mucosal surfaces, is recommended (N95/FFP2 respirator, gown, double gloves, goggles or face shield and head cover). For long duration AGMPs that are deemed high-risk in COVID-19 positive patients, Level 3 PPE can provide a higher level of protection and be more comfortable during long duration surgeries if surgical hoods or PAPRs are used. It is recommended that these procedures are performed in negative pressure rooms, if available. It is essential to follow strict donning and doffing protocols to minimize the risk of contamination.

Conclusions

By following strict infection prevention recommendations, the risk of HCWs becoming infected with SARS-CoV-2 while treating patients can be minimized. As the COVID-19 pandemic evolves rapidly, these recommendations should serve as guidance and need to be interpreted based on local factors and availability of healthcare resources.

Cost-effectiveness of School Hearing Screening Programs: A Scoping Review

Objective

School hearing screening is a public health intervention that can improve care for children who experience hearing loss that is not detected on or develops after newborn screening. However, implementation of school hearing screening is sporadic and supported by mixed evidence to its economic benefit. This scoping review provides a summary of all published cost-effectiveness studies regarding school hearing screening programs globally. At the time of this review, there were no previously published reviews of a similar nature.

Data Sources

A structured search was applied to 4 databases: PubMed (Medline), Embase, CINAHL, and Cochrane Library.

Review Methods

The database search was carried out by 2 independent researchers, and results were reported in accordance with the PRISMA-ScR checklist and the JBI methodology for scoping reviews. Studies that included a cost analysis of screening programs for school-aged children in the school environment were eligible for inclusion. Studies that involved evaluations of only neonatal or preschool programs were excluded.

Results

Four of the 5 studies that conducted a cost-effectiveness analysis reported that school hearing screening was cost-effective through the calculation of incremental cost-effectiveness ratios (ICERs) via either quality- or disability-adjusted life years. One study reported that a new school hearing screening program dominated the existing program; 2 studies reported ICERs ranging from 1079 to 4304 international dollars; and 1 study reported an ICER of £2445. One study reported that school-entry hearing screening was not cost-effective versus no screening.

Conclusion

The majority of studies concluded that school hearing screening was cost-effective. However, significant differences in methodology and region-specific estimates of model inputs limit the generalizability of these findings.

The prognostic value and pathophysiologic significance of three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) magnetic resonance imaging in idiopathic sudden sensorineural hearing loss: A systematic review and meta-analysis

BACKGROUND

The underlying pathophysiology of idiopathic sudden sensorineural hearing loss (ISSNHL) is still unknown. However, an increasing number of observational studies report intralabyrinthine signal alterations in patients with ISSNHL using three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) magnetic resonance imaging (MRI). These findings warrant a meta-analysis.

OBJECTIVE OF REVIEW

To conduct a meta-analysis assessing the value of 3D-FLAIR MRI in identifying possible underlying labyrinthine pathophysiologic mechanisms and prognostication in patients with ISSNHL.

SEARCH STRATEGY

Two reviewers independently searched the Pubmed, Embase and Cochrane Library from inception until October 10, 2018 and evaluated eligibility based on titles and abstracts of all retrieved studies. All studies reporting on 3D-FLAIR imaging in ISSNHL were included. Subsequently, the full text of eligible studies were evaluated.

EVALUATION METHOD

Adhering to the MOOSE guideline, two independent reviewers extracted data, assessed risk of bias and evaluated the relevance and quality of evidence. Data on the number of patients and events were extracted and hearing levels were converted to standardised mean differences (SMD) for conducting meta-analyses. Random effects models for meta-analyses were applied.

RESULTS

Eight observational studies met our inclusion criteria (n = 638 patients). In 29%, high signal intensity was found on 3D-FLAIR imaging, suggesting labyrinthine pathology (labyrinthitis [79%], intralabyrinthine haemorrhage [21%]). High signal intensity on 3D-FLAIR was associated with poorer hearing (SMD: 14 dB, 95% CI 5.67-22.94) and vertigo (RR: 1.92, 95% CI 1.16-3.17) at baseline. Multivariate analyses demonstrated that patients with high 3D-FLAIR signal intensity had 21 dB lower final hearing pure-tone averages (SMD: 21 dB, 95% CI 9.08-33.24).

CONCLUSIONS

Three-dimensional fluid-attenuated inversion recovery MR imaging can identify an underlying labyrinthine condition in up to 29% of patients with sudden hearing loss in whom previously no cause could be identified. Their final pure-tone averages are more than 20 dB worse than 3D-FLAIR-negative patients, suggesting more severe labyrinthine damage. Findings such as these may contribute to our understanding of pathophysiologic mechanisms of ISSNHL.

Subjective and objective vestibular changes that occur following paediatric cochlear implantation: systematic review and meta-analysis

Objective

Cochlear implantation can result in post-operative vestibular dysfunction of unknown clinical significance. The objective of this study was to characterize the presence, magnitude, and clinical significance of vestibular dysfunction that occurs after pediatric cochlear implantation.

Data sources

The databases Embase, Medline (OvidSP), and PubMed were used. Only articles published in English were included. Grey literature and unpublished sources were also reviewed.

Study selection

Articles published from 1980 until the present which documented pre-operative and post-operative vestibular testing on children under the age of 18 were used.

Data extraction

Parameters that were assessed included number of patients, pre- and post-operative vestibular-evoked myogenic potentials (VEMPs), head impulse testing (HIT), calorics, and posturography, timing of pre- and post-operative testing, symptomatology, and other demographic data such as etiology of the hearing loss.

Data synthesis

Ten articles were included. Relative risk values evaluating the effect of cochlear implantation on vestibular function were calculated for VEMPs and caloric testing due to the availability of published data. I² values were calculated and 95% confidence intervals were reported. Separate analyses were conducted for each individual study and a pooled analysis was conducted to yield an overall relative risk. Assessment on risk of bias in individual studies and overall was performed.

Conclusion

Pediatric cochlear implantation is associated with a statistically significant decrease in VEMP responses post-operatively (RR 1.8, p < 0.001, I² 91.86, 95%CI 1.57–2.02). Similar results are not seen in caloric testing. Insufficient data is available for analysis of HIT and posturography. Further studies are necessary to determine the effect of cochlear implantation on objective vestibular measures post-operatively and whether any changes seen are clinically relevant in this population.

Differential Recovery in Early- and Late-Onset Delayed Facial Palsy Following Vestibular Schwannoma Resection

BACKGROUND

Delayed facial palsy (DFP) after resection of vestibular schwannomas (VS) is worsening of facial nerve function after an initially normal postoperative result.

OBJECTIVE

To characterize different types of DFP, compare recovery rates, and review of series of outcomes in patients following resection of VS.

METHODS

Between 2001 and 2017, 434 patients (51% female) with VS underwent resection. We categorized the patients who developed facial palsy into groups based on timing of onset after surgery, immediate facial palsy (IFP), early-onset DFP (within 48 h), and late-onset DFP (after 48 h). Introduction of facial nerve motor-evoked potentials (fMEP) in 2002 and a change of practice utilizing perioperative minocycline in 2005 allowed for historical analysis of these interventions.

RESULTS

Mean age of study cohort was 49.1 yr (range 13-81 yr), with 19.8% developing facial palsy. The late-onset DFP group demonstrated a significantly faster recovery than the early-onset DFP group (2.8 ± 0.5 vs 47 ± 8 wk, P &lt; .0001), had prolonged latency to palsy onset after initiating perioperative minocycline (7.3 vs 12.5 d, P = .001), and had a nonsignificant trend towards faster recovery from facial palsy with use of minocycline (2.6 vs 3.4 wk, P = .11).

CONCLUSION

Given the timings, it is likely axonal degeneration is responsible for early-onset DFP, while demyelination and remyelination lead to faster facial nerve recovery in late-onset DFP. Reported anti-apoptotic properties of minocycline could account for the further delay in onset of DFP, and possibly reduce the rate and duration of DFP in the surgical cohort.

Post-Traumatic Dizziness: Clinical and Medicolegal Aspects

Subjective complaints of dizziness after mild-to-moderate traumatic brain injury are common. Alterations in the mode of injury have changed the presentation symptoms. Evolutions in neuroimaging challenge conventional concepts regarding lack of evidence of injury following mild head trauma and provide hope for elucidating the site of lesion in patients with post-traumatic balance symptoms. Yet the vestibular clinician must maintain a healthy level of suspicion regarding potential exaggeration of symptoms and disability in patients with a financial incentive. Unique conditions warrant particular attention by the vestibular clinician, including chronic traumatic encephalopathy, catastrophization, and persistent postural and perceptual dizziness. The clinical significance of abnormalities, particularly on vestibular-evoked myogenic potential testing, needs to be better defined prior to their widespread application in the medical legal arena. The role of the medical expert is to provide opinion on matters requiring special knowledge to assist the court in reaching its findings. As such, this chapter provides an update on recent advances to consider in patients with dizziness after trauma.

Vestibular Neuritis: Recent Advances in Etiology, Diagnostic Evaluation, and Treatment

Purpose of Chapter: This chapter highlights the recent advances in etiology, diagnostic evaluation, and management of vestibular neuritis (VN). Recent Findings: The viral hypothesis has been strengthened with new evidence as the main etiology of VN. Recent evidence indicates that bedside oculomotor findings play a critical role in differentiating VN from stroke. The implementation of cervical and ocular vestibular evoked myogenic potential, and video head impulse test in vestibular function testing has made it possible to diagnose selective damage of the vestibular nerves. The management of the acute phase of VN is primarily medical, while long-term treatment is designed to improve vestibular compensation. Summary: VN is clearly defined as an important viral inner ear disorder.

Shared decision making and decisional conflict in the Management of Vestibular Schwannoma: a prospective cohort study

Background

Patients with vestibular schwannomas (VS) are faced with complex management decisions. Watchful waiting, surgical resection, and radiation are all viable options with associated risks and benefits. We sought to determine if patients with VS experience decisional conflict when deciding between surgery or non-surgical management, and factors influencing the degree of decisional conflict.

Methods

A prospective cohort study in two tertiary ambulatory skull-base clinics was performed. Patients with newly diagnosed or newly growing vestibular schwannomas were recruited. Patients were given a demographic form and the decisional conflict scale (DCS), a validated measure to assess the degree of uncertainty when making medical decisions. The degree of shared decision making (SDM) experienced by the patient and physician were assessed via the SDM-Q-10 and SDM-Q-Doc questionnaires, respectively. Non-parametric statistics were used. Questionnaires and demographic information were correlated with DCS using Spearman correlation coefficient and Mann-Whitney U. Logistic regression was performed to determine factors independently associated with DCS scores.

Results

Seventy-seven patients participated (55% female, aged 37–81 years); VS ranged in size from 2 mm–50 mm. Significant decisional conflict (DCS score 25 or greater) was experienced by 17 (22%) patients. Patients reported an average SDM-Q-10 score of 86, indicating highly perceived level of SDM. Physician and patient SDM scores were weakly correlated (p = 0.045, Spearman correlation coefficient 0.234). DCS scores were significantly negatively correlated with a decision to pursue surgery, presence of a trainee, and higher SDM-Q-10 score. DCS was higher with female gender. Using logistic regression, the SDM-Q-10 score was the only variable associated with significantly reduced DCS.

Conclusions

About one fifth of patients deciding how to manage their vestibular schwannoma experienced a significant degree of decisional conflict. Involving the patients in the process through shared decision-making significantly reduced the degree of uncertainty patients experienced.

Health care professionals' neckties as a source of transmission of bacteria to patients: a systematic review

BACKGROUND

There is growing concern that neckties worn by health care professionals may contribute to infections contracted in health care settings. We evaluated the evidence for health-care-associated infections resulting from neckties and whether the evidence is sufficient to warrant a tieless policy in Canada.

METHODS

We performed a systematic review to determine whether neckties worn by health care professionals colonize harmful pathogenic bacteria and whether they contribute to the spread of infection to patients in the inpatient or outpatient setting. We searched PubMed (1966 to 2017) and Embase (1974 to 2017). The level of evidence was appraised according to the Oxford Centre for Evidence-Based Medicine levels of evidence. We evaluated the quality of evidence and the risk of bias using the Jadad scale or the Newcastle-Ottawa Scale.

RESULTS

We screened 1675 citations, of which 6 were ultimately included in the systematic review. Only 1 study gave level 1b evidence (randomized controlled trial). Neckties were more likely than shirt pockets to colonize bacteria. There is limited evidence that neckties may be contaminated with pathogenic bacteria (e.g., methicillin-resistant Staphylococcus aureus) and very limited evidence that contaminated neckties may transmit bacteria (in a controlled experimental setting to a mannequin).

INTERPRETATION

There is no evidence of increased rates of health-care-associated infections related to the wearing of neckties by health care professionals. There is weak evidence that neckties are contaminated with pathogenic (and nonpathogenic) bacteria. The level of evidence was weak and the studies were heterogeneous. Evidence to support the need for a tieless dress code policy is lacking.

Threat effects on human oculo-motor function

Neuro-anatomical evidence supports the potential for threat-related factors, such as fear, anxiety and vigilance, to influence brainstem motor nuclei controlling eye movements, as well as the vestibular nuclei. However, little is known about how threat influences human ocular responses, such as eye saccades (ES), smooth pursuit eye tracking (SP), and optokinetic nystagmus (OKN), and whether these responses can be facilitated above normal baseline levels with a natural source of threat. This study was designed to examine the effects of height-induced postural threat on the gain of ES, SP and OKN responses in humans. Twenty participants stood at two different surface heights while performing ES (ranging from 8° to 45° from center), SP (15, 20, 30°/s) and OKN (15, 30, 60°/s) responses in the horizontal plane. Height did not significantly increase the slope of the relationship between ES peak velocity and initial amplitude, or the gain of ES amplitude. In contrast height significantly increased SP and OKN gain. Significant correlations were found between changes in physiological arousal and OKN gain. Observations of changes with height in OKN and SP support neuro-anatomical evidence of threat-related mechanisms influencing both oculo-motor nuclei and vestibular reflex pathways. Although further study is warranted, the findings suggest that potential influences of fear, anxiety and arousal/alertness should be accounted for, or controlled, during clinical vestibular and oculo-motor testing.

Mental practice in postgraduate training: a randomized controlled trial in mastoidectomy skills

Background

Mental practice, the cognitive rehearsal of a task in the absence of overt physical movement, has been successfully used in teaching complex psychomotor tasks including sports and music, and recently, surgical skills.

The objectives of this study were, 1) To develop and evaluate a mental practice protocol for mastoidectomy 2) To assess the immediate impact of mental practice on a mastoidectomy surgical task among senior Otolaryngology─Head & Neck Surgery (OHNS) residents.

Method

Three expert surgeons were interviewed using verbal protocol analysis to develop a mastoidectomy mental practice script. Twelve senior Residents from Canadian training programs were randomized into two groups. All Residents were video-recorded performing a baseline mastoidectomy in a temporal bone lab. The intervention group received mental practice training, while the control group undertook self-directed textbook study. All subjects were then video-recorded performing a second mastoidectomy. Changes in pre- and post-test scores using validated expert ratings, the Task Specific Evaluation of Mastoidectomy and the Global Evaluation of Mastoidectomy, were statistically analyzed.

Results

A mental practice script was successfully developed based on interviews of three expert surgeon-educators. Task Specific Evaluation and Global Evaluation scores increased in both the mental practice and textbook study groups; there was no significant difference between the two groups in the change in scores post-intervention. There was a high and statistically signficant correlation between evaluators on the outcome measures.

Conclusions

We were not able to demonstrate a significant difference for the benefits of mental practice in mastoidectomy, possibly due to the sample size. However, mental practice is a surgical education tool which is portable, accessible, inexpensive and safe.

Electronic supplementary material

The online version of this article (doi:10.1186/s40463-016-0162-2) contains supplementary material, which is available to authorized users.

Vestibulo-spinal and vestibulo-ocular reflexes are modulated when standing with increased postural threat

We investigated how vestibulo-spinal reflexes (VSRs) and vestibulo-ocular reflexes (VORs) measured through vestibular evoked myogenic potentials (VEMPs) and video head impulse test (vHIT) outcomes, respectively, are modulated during standing under conditions of increased postural threat. Twenty-five healthy young adults stood quietly at low (0.8 m from the ground) and high (3.2 m) surface height conditions in two experiments. For the first experiment (n = 25) VEMPs were recorded with surface EMG from inferior oblique (IO), sternocleidomastoid (SCM), trapezius (TRP), and soleus (SOL) muscles in response to 256 air-conducted short tone bursts (125 dB SPL, 500 Hz, 4 ms) delivered via headphones. A subset of subjects (n = 19) also received horizontal and vertical head thrusts (∼150°/s) at each height in a separate session, comparing eye and head velocities by using a vHIT system for calculating the functional VOR gains. VEMP amplitudes (IO, TRP, SOL) and horizontal and vertical vHIT gains all increased with high surface height conditions (P < 0.05). Changes in IO and SCM VEMP amplitudes as well as horizontal vHIT gains were correlated with changes in electrodermal activity (ρ = 0.44-0.59, P < 0.05). VEMP amplitude for the IO also positively correlated with fear (ρ = 0.43, P = 0.03). Threat-induced anxiety, fear, and arousal have significant effects on VSR and VOR gains that can be observed in both physiological and functional outcome measures. These findings provide support for a potential central modulation of the vestibular nucleus complex through excitatory inputs from neural centers involved in processing fear, anxiety, arousal, and vigilance.

Clinical and Radiographic Factors Predicting Hearing Preservation Rates in Large Vestibular Schwannomas

Objectives Postoperative hearing preservation rates for patients with large vestibular schwannomas range from 0 to 43%. The clinical and radiographic factors predicting hearing preservation in smaller vestibular schwannomas are well described; however, their importance in larger tumors is unclear. We investigated factors predicting hearing preservation in large vestibular schwannomas. Design Retrospective review. Setting Quaternary care academic center. Participants A total of 85 patients with unilateral vestibular schwannomas > 3 cm underwent retrosigmoid resections. Main Outcomes Measures Preoperative and postoperative serviceable hearing rates. Methods Clinical and radiographic data including preoperative and postoperative audiograms, preoperative symptoms, magnetic resonance imaging features, and postoperative facial weakness were analyzed. Results Hearing was preserved in 41% of patients (17 of 42) with preoperative serviceable hearing. Hypertension and diabetes increased the likelihood of preoperative hearing loss. Preoperative tinnitus predicted a lower likelihood of hearing preservation. No radiographic factors predicted hearing preservation; however, larger tumor size, smaller fourth ventricular width, and the presence of a cerebrospinal fluid cleft surrounding the tumor predicted postoperative facial weakness. Conclusion Systemic comorbidities may influence hearing loss preoperatively in patients with large vestibular schwannomas. The absence of tinnitus may reflect hearing reserve and propensity for hearing preservation. Preoperative radiographic features did not predict hearing preservation despite some associations with postoperative facial weakness.

Symptom Resolution Rates of Posttraumatic versus Nontraumatic Benign Paroxysmal Positional Vertigo

Objective

To determine the rate of symptom resolution in patients with posttraumatic benign paroxysmal positional vertigo (BPPV) and to determine if it differs from resolution rates in patients with BPPV and without a history of head trauma.

Data Sources

Systematic review of the literature was performed using Medline, EMBASE, and Cochrane databases. English and French articles meeting inclusion criteria and published between 1946 and October 2014 were included.

Review Methods

Data were independently extracted from the articles by 2 reviewers using data collection forms developed a priori. Inclusion and exclusion criteria were decided a priori. Studies were included if they reported on at least 1 case of posttraumatic BPPV (t-BPPV), reported on outcomes of all patients with t-BPPV, had a clearly defined inception point, and provided a clear diagnosis of BPPV (defined a priori by reviewers).

Results

A total of 3017 titles, 362 abstracts, and 67 articles were reviewed, from which 16 articles met inclusion criteria and underwent data extraction. There were a total of 207 patients with posttraumatic BPPV identified. Among the 207 patients, 151 (73%) had resolution of symptoms. The T-BPPV patients may have more multi-canal involvement and may require more repositioning maneuvers for resolution compared to patients with nontraumatic BPPV.

Conclusions

Available evidence does not support the notion that symptom resolution rates in patients with posttraumatic BPPV are worse than those with nontraumatic BPPV. However, well-designed studies with adequate cohorts are lacking. Additional well-executed studies are needed to confirm this lack of difference in resolution rates.

Nocardia asteroides sinusitis in a pediatric patient: Case report with 20 year follow-up and review of the literature

Nocardia Asteroides infection in a non-immunocompromised pediatric patient is extremely rare. We present a case of ethmoid sinusitis and orbital subperiosteal abscess caused by N. asteroides with a 20 year follow up and a review of the literature. N. asteroides was grown from intraoperative cultures for mycobacteria following surgical incision and drainage of the abscess. Postoperatively, the patient received a seven month course of trimethoprim-sulfamethozaxole and had no subsequent sequelae. Nocardia infections are common in immunocompromised patients. We present what we believe to be the first case of pediatric Nocardia sinusitis with 20-year follow up.

A meta-analysis and systematic review of the prevalence of mitochondrially encoded 12S RNA in the general population: Is there a role for screening neonates requiring aminoglycosides?

BACKGROUND

This was a meta-analysis and systematic review to determine the global prevalence of the mitochondrially encoded 12S RNA (MT-RNR1) genetic mutation in order to assess the need for neonatal screening prior to aminoglycoside therapy.

MATERIALS AND METHODS

A comprehensive search of MEDLINE, EMBASE, Ovid, Database of Abstracts of Reviews of Effect, Cochrane Library, Clinical Evidence and Cochrane Central Register of Trials was performed including cross-referencing independently by 2 assessors. Selections were restricted to human studies in English. Meta-analysis was done with MetaXL 2013.

RESULTS

Forty-five papers out of 295 met the criteria. Pooled prevalence in the general population for MT-RNR1 gene mutations (A1555G, C1494T, A7445G) was 2% (1-4%) at 99%.

CONCLUSION

Routine screening for MT-RNR1 mutations in the general population prior to treatment with aminoglycosides appear desirable but poorly supported by the weak level of evidence available in the literature. Routine screening in high-risk (Chinese and Spanish) populations appear justified.

Lack of Association between Human Herpesvirus and Vestibular Schwannoma

Objective

To assess for the presence of human herpesvirus (HHV) using immunohistochemical and polymerase chain reaction (PCR) assay in surgically excised vestibular schwannoma (VS) samples.

Study Design

Cross-sectional study.

Setting

A retrospective laboratory-based study of tumors from patients with vestibular schwannoma.

Subjects and Methods

Tissue microarrays (TMAs) representing sporadic and NF2-associated VS from 121 patients, as well as appropriate positive and negative controls, were studied. TMA sections were immunostained using antibodies directed against HHV-1, HHV-2, HHV-3, HHV-4, HHV-5, and HHV-8. PCR was used for the detection of all 8 known human herpesviruses.

Results

There was no detectable HHV (HHV-1, HHV-2, HHV-3, HHV-4, HHV-5, HHV-8) by immunohistochemistry in any of the 121 cases of sporadic and NF2 cases analyzed. These data were further validated by DNA sequence analyses using PCR in a subset of the VS samples, all of which were found to be negative for all HHV.

Conclusions

The data offer no support for an association between HHV and the development of sporadic or NF2-associated VS in humans.

In vitro efficacy of N-acetylcysteine on bacteria associated with chronic suppurative otitis media

Background

The safety and efficacy of Ciprodex® has been demonstrated for treatment of chronic suppurative otitis media (CSOM). However, symptoms fail to resolve in 9-15% of patients. The objective of this study is to evaluate the efficacy of N-acetylcysteine (NAC) on S. aureus, and planktonic and sessile (biofilm forming) P. aeruginosa in vitro using clinical isolates from patients with CSOM.

Methods

1) Stability was assessed using liquid chromatography-mass spectrometry for each component in a prepared mixture of Ciprodex® and NAC over 15 days. Sterility was assessed by measuring bacterial growth on a blood agar plate. Efficacy was assessed using a disc diffusion method by inoculating plates with S. aureus ATCC 29513 and P. aeruginosa ATCC 27853, and measuring the clearance zone.

2) Fifteen P. aeruginosa strains were isolated from patients with CSOM and tested in vitro using the bioFILM PA™ antimicrobial susceptibility assay. Treatment solutions included Ciprodex® & ciprofloxacin +/- NAC, and NAC alone (0.25%, 0.5% & 1.25%).

Results

1) NAC combined with Ciprodex® demonstrated stability, sterility, and efficacy over a two-week period

2) P. aeruginosa strains in the sessile (33%-40%) and planktonic (13%) state demonstrated resistance to Ciprodex® and ciprofloxacin. When NAC ≥0.5% was used in isolation or as an adjunct to either of these medications, no resistance was found in the sessile or planktonic state among all 15 strains.

Conclusion

1) Ciprodex® combined with NAC has a shelf life of at least two weeks given the documented preservation of stability, sterility, and clinical efficacy of the mixed compounds.

2) P. aeruginosa strains demonstrated resistance to both Ciprodex® and ciprofloxacin. NAC ≥0.5% overcomes issues with resistance and shows promise in the treatment of CSOM.

A Lack of Association between Human Herpes Viridiae (HHV) and Vestibular Schwannoma: Analysis of 121 Cases

Objectives:

Vestibular schwannoma (VS) is a benign tumor thatarises from the Schwann cells of the vestibular nerve. Human herpes virus (HHV) 1 and 2 have been found within the parenchyma of virtually all the organs of the body and the dorsal root ganglia of the spinal cord in humans. HHV has been shown to replicate within Schwann cells, and infection by HHV has been shown to mimic VS on magnetic resonance imaging. Others hypothesized that the likely cause of VS is HHV infection and that prior exposure to HHV-3 is a potential risk factor in VS development. Our objective wasto assess for the presence of HHV viral DNA using immunohistochemical techniques in surgically excised vestibular schwannoma samples.

Methods:

Tissue microarrays (TMAs) representing sporadic and NF2-associated vestibular schwannomas from 121 patients, as well as both positive and negative controls, were studied. TMA sections were immunostained-using antibodies directed against HHV-1, HHV-2, HHV-3, HHV-5, and HHV-8.

Results:

There was no immunohistochemically detectable HHV (HHV-1, HHV-2, HHV-3, HHV-5, HHV-8) in any of the 121 cases of sporadic or NF2 cases analyzed.

Conclusions:

These data offer no support for an association between HHV and the development of sporadic or NF2 associated VS in humans.

Prevalence of MT-RnR1 in the General Population

Objective: Review the prevalence of MT-RNR1 genetic mutation and assess the need for neonatal screening prior to gentamicin therapy. A comprehensive search of MEDLINE, EMBASE, Cochrane Library, Clinical Evidence, and Cochrane Central Register of Trials was performed. The reference lists were cross-referenced. Review was restricted to human studies in English language.

Method: Studies describing the prevalence/incidence of MT-RNR1 gene mutations (A1555G, C1494T, A7445G) in the population. Relevant studies screening for presence for MT-RNR1 in patients receiving aminoglycoside therapy were included.

Results: Twenty-two articles out of 67 full papers and 206 abstracts from 1948 to November 2011 met the inclusion criteria. These included 9 prospective case-control studies, 12 case series, and a case report. There is weak evidence that MT-RNR1 is globally prevalent with racial bias especially in Chinese and Spanish populations. The prevalence/incidence ranged from 0.09%-2.9% in general population to 17% in the high-risk population. Weak evidence of neonatal sensorineural hearing loss following aminoglycoside exposure was also seen.

Conclusion: There is a need for large national epidemiological studies to assess the prevalence of MT-RNR. Some evidence of a global prevalence of MT-RNR1 with racial bias and link between aminoglycoside exposure and NSHL among at risk group. It is difficult to justify routine screening of patients for MT-RNR1 with the available literature.

Systematic review and meta-analysis of the risk factors for sudden sensorineural hearing loss in adults

OBJECTIVES/HYPOTHESIS

To review the medical literature evidence of potential risk factors for sudden sensorineural hearing loss (SSNHL) in the adult general population.

STUDY DESIGN

Systematic review of prospective and retrospective studies; meta-analysis of case-controlled studies.

METHODS

Three researchers independently reviewed MEDLINE (January 1, 1950-November 30, 2010), Embase (January 1, 1980-November 30, 2010), and Evidence-Based Medicine Reviews databases in addition to conducting a manual reference search. Randomized controlled trials, prospective cohort studies, consecutive/nonconsecutive case series, and retrospective reviews in which a clear definition of SSNHL was stated were included in the study. Researchers individually extracted data regarding patient information and the presumed risk factors. Discrepancies were resolved by mutual consensus.

RESULTS

Twenty-two articles met the inclusion criteria. Cardiovascular risk factors (smoking, increased alcohol consumption) appeared to be associated with a higher risk of developing SSNHL. A low level of serum folate may also be implicated as a risk factor. Factor V Leiden and MTHFR gene polymorphisms were found to occur more frequently in patients with SSNHL in several studies, suggesting these inherited prothrombophilic mutations could be independent risk factors of SSNHL.

CONCLUSIONS

Acquired and inherited cardiovascular risk factors appeared to be associated with an increased risk of developing SSNHL.

Avoiding the “Deadly Sins” of Humanitarian Missions: How to “Do Good” Better

Program Description: Over the past several decades, the numbers of North American physicians and surgeons engaged in international humanitarian missions has increased dramatically. Such trips often provide an opportunity for needy individuals and communities to receive care that would otherwise be unavailable to them. They also provide the opportunity for participants to “give back” through providing direct patient care and teaching in an environment of extreme need. Personal motivations, level of ability of the individual practitioner, sophistication of the mission organization, as well as level of connectedness to “in country” providers varies dramatically among mission groups. This variability has contributed to some unfortunate patient outcomes. Accusations that “surgical safaris” represent a “form of Neo-colonialism” have cast doubt on the motivations of participants and brought significant scrutiny to the true benefits arising from these efforts. This interactive miniseminar will explore “deadly sins” which are common to medical humanitarian efforts as well as issues which are unique to surgical humanitarian missions. Panelists will discuss available data and areas in which there is a lack of data concerning humanitarian efforts. Finally, “best practices” for humanitarian missions will be discussed. Issues to be discussed include appropriate standard of care, duration, follow-up, conduct of research, resident trainee participation in surgical procedures, role of the media, and integration with local care systems.

Educational Objectives: 1) Identify common problems encountered during medical and surgical humanitarian mission trips. 2) Understand ethical concerns arising during international humanitarian efforts. 3) Apply best practices for conduct of humanitarian mission trips in which they are involved.

Prospective, randomized controlled assessment of the short- and long-term efficacy of a hearing conservation education program in Canadian elementary school children

OBJECTIVE

To assess the efficacy of a hearing conservation program in changing acoustic risk-taking and hearing conservation behaviors in elementary school children.

STUDY DESIGN

Prospective, randomized, mixed design controlled study.

METHODS

Participants were grade-six students from 16 Vancouver School Board schools. Differences between the intervention and control group responses on a behavioral questionnaire were measured at baseline, and then at 2 weeks and 6 months after administration of a hearing conservation program (Sound Sense™).

RESULTS

The intervention resulted in significant interactions for improved earplug use at dances (P = .019), rock concerts (P = .001), with percussion musical instruments (P = .002), and electric guitars (P = .028) at 2 weeks postintervention relative to baseline. Improvements in children's earplug use at dances (P = .041), rock concerts (P = .0024), and with power lawn mowers (P = .043) at 6 months postintervention relative to baseline were also observed. Behavior in the intervention group compared to control group improved in earplug use with any "other noises" at 2 weeks (P = .001), and 6 months (P = .022) relative to baseline. There was a tendency in the intervention group to reduce the duration of use of personal music devices at 2 weeks and 6 months after the hearing conservation program, which was nonsignificant.

CONCLUSION

The Sound Sense™ hearing conservation program improved earplug use practices in elementary school children in the short and long term. The development, implementation and evaluation of a community-based health promotion project around hearing loss can serve as a tremendous opportunity for students to develop their knowledge and skills in health advocacy.

Systematic review of the evidence for the etiology of adult sudden sensorineural hearing loss

OBJECTIVES/HYPOTHESIS

To determine the evidence for different etiologies of sudden sensorineural hearing loss (SSNHL) identified by clinical diagnostic tests in the adult population.

STUDY DESIGN

Systematic literature review.

METHODS

Review of MEDLINE (1950-October 2009), EMBASE (1980-October 2009), and EBM Review databases in addition to manual reference search of identified papers. Randomized controlled trials, prospective cohort studies, and retrospective reviews of consecutive patients in which a clear definition of SSNHL was stated and data from consecutive patients were reported with respect to etiology of hearing loss. Three researchers independently extracted data regarding patient demographic information, diagnostic tests employed, and the identified presumed etiologies. Discrepancies were resolved by mutual consensus.

RESULTS

: Twenty-three articles met the inclusion criteria. The first group of papers searched for different etiologies among patients with SSNHL. Multiple etiologies were identified, including viral infection, vascular impairment, autoimmune disease, inner ear pathology, and central nervous system anomalies. The diagnosis for the majority of patients remained idiopathic. The second group of papers evaluated SSNHL patients with specific diagnostic tests such as autoimmune markers, hemostatic parameters, and diagnostic imaging.

CONCLUSIONS

The suspected etiologies for patients suffering sudden sensorineural hearing loss included idiopathic (71.0%), infectious disease (12.8%), otologic disease (4.7%), trauma (4.2%), vascular or hematologic (2.8%), neoplastic (2.3%), and other causes (2.2%). Establishment of a direct causal link between SSNHL and these etiologies remains elusive. Diagnostic imaging is a useful method for identification of temporal bone or intracranial pathology that can present with SSNHL as a primary symptom.

Holiday review. How random is the toss of a coin?

BACKGROUND

The toss of a coin has been a method used to determine random outcomes for centuries. It is still used in some research studies as a method of randomization, although it has largely been discredited as a valid randomization method. We sought to provide evidence that the toss of a coin can be manipulated.

METHODS

We performed a prospective experiment involving otolaryngology residents in Vancouver, Canada. The main outcome was the proportion of "heads" coin tosses achieved (out of 300 attempts) by each participant. Each of the participants attempted to flip the coin so as to achieve a heads result.

RESULTS

All participants achieved more heads than tails results, with 7 of the 13 participants having significantly more heads results (p<or=0.05). The highest proportion of heads achieved was 0.68 (95% confidence interval 0.62-0.73, p<0.001).

INTERPRETATION

Certain people are able to successfully manipulate the toss of a coin. This throws into doubt the validity of using a coin toss to determine a chance result.

Primary middle ear Epstein-Barr virus-related lymphoepithelial carcinoma: case reports and systematic review

OBJECTIVES/HYPOTHESIS

To report two cases of primary lymphoepithelial carcinoma in the middle ear and to determine the optimal treatment for such lesions.

STUDY DESIGN/METHODS

Case reports and a systematic review of the literature.

RESULTS

Primary lymphoepithelial carcinoma in the middle ear is an exceptionally rare condition with only two other cases reported in the literature. There appears to be an association with Epstein-Barr virus infection and in those patients originating from the Guangdong province of China, much as is the case for similar lesions found in the nasopharynx. Piecemeal rather than en bloc excision, in combination with adjuvant radiotherapy, appears to adequately control the disease.

CONCLUSIONS

Primary lymphoepithelial carcinoma of the middle ear is a rare lesion, which when treated has a good prognosis.

Toward the development of evidence-based guidelines for the management of methicillin-resistant Staphylococcus aureus otitis

OBJECTIVES

(1) To determine the causative bacteriology of discharging ears in a case series from a tertiary/quaternary academic centre serving an urban population and from a review of the literature and (2) to develop treatment guidelines for methicillin-resistant Staphylococcus aureus (MRSA) otorrhea based on the best available evidence.

METHODS

A retrospective analysis of all "ear" cultures from the microbiology laboratory at St. Paul's Hospital, Vancouver, was performed to ascertain a qualitative analysis on the susceptibility and bacteriology data. A systematic review of the literature was performed for all studies examining the bacteriology, susceptibility, and treatment for any MRSA infection producing otorrhea.

RESULTS

Staphylococcus aureus and Pseudomonas aeruginosa (PA) were present in 39.7% and 13.5%, respectively, of ear cultures obtained at our institution versus 9.9 to 54.1% and 25.0 to 48.6% in identified studies in the literature. Methicillin-sensitive Staphylococcus aureus (MSSA) was present more frequently than MRSA (31.2% vs 8.5% at our institution; 16.9% vs 6.9% in the literature). MRSA isolates were often resistant to gentamicin (14.8%) and ciprofloxacin (7.7%) but susceptible to trimethoprim-sulfamethoxazole (TMP-SMX) (85.3%) and fusidic acid (96.3%), suggesting a preponderance of the "community strain" of MRSA.

CONCLUSION

The susceptibility of MRSA to antibiotics in commonly used otic drops (ie, gentamicin and ciprofloxacin) is low. Based on the available data, we suggest an evidence-based approach to the management of MRSA otorrhea considering whether the strain is community or hospital acquired and whether the tympanic membrane is intact.

A systematic review of pediatric sensorineural hearing loss in congenital syphilis

INTRODUCTION

Congenital syphilis is a known cause of progressive sensorineural hearing loss. The prevalence of syphilitic sensorineural hearing loss (SNHL) in childhood is not clearly defined.

OBJECTIVE

To determine the frequency and characteristics of pediatric SNHL following intrauterine infection with or exposure to Treponema pallidum in order to develop evidence-based guidelines for audiologic monitoring.

DATA SOURCES

Medline (1950-March 2008), EMBASE (1980-March 2008), CINAHL (1982-March 2008), BIOSIS Previews (1969-March 2008), and Cochrane databases. Manual search of references of identified articles and book chapters.

STUDY SELECTION

Articles with an inception cohort of children infected with T. pallidum during pregnancy, positive serological identification of syphilis infection in the antenatal period or pathognomonic clinical signs of congenital syphilis infection, and longitudinal serial audiologic evaluations to identify the prevalence and progression of SNHL.

DATA EXTRACTION

Patient information, maternal and infant serologic status, and audiometric data extracted in an independent fashion. Discrepancies resolved through mutual consensus.

DATA SYNTHESIS

Descriptive statistics.

RESULTS

One prospective cohort study met the inclusion criteria. No cases of SNHL in infants with early congenital syphilis treated with antibiotics in the neonatal period were identified.

CONCLUSIONS

There have been no reports of children with confirmed congenital SNHL secondary to in utero syphilis infection. Newborns with positive syphilis serology should have hearing screening performed at birth and receive treatment with an appropriate course of penicillin therapy. Longitudinal hearing screening is recommended for all pediatric patients with congenital syphilis, as further studies documenting longitudinal audiometric data for patients previously treated either fully or partly for congenital syphilis are required.

A systematic review of neonatal toxoplasmosis exposure and sensorineural hearing loss

INTRODUCTION

The Joint Committee on Infant Hearing 2007 Position Statement includes in utero toxoplasmosis infection as a risk indicator for delayed-onset or progressive sensorineural hearing loss. It is recommended that children with congenital toxoplasmosis infection undergo audiologic monitoring to identify congenital and delayed-onset sensorineural hearing loss.

OBJECTIVE

To determine the prevalence of sensorineural hearing loss and to develop evidence-based guidelines for audiologic monitoring of children born with congenital toxoplasmosis infection.

DATA SOURCES

Systematic search of Medline, EMBASE and Cochrane databases and manual search of references.

STUDY SELECTION

Longitudinal studies reporting an inception cohort identified at birth, with serologic confirmation of toxoplasmosis infection, and long-term serial audiometric evaluation.

DATA EXTRACTION

Independent extraction of patient and audiometric data.

DATA SYNTHESIS

Descriptive statistics.

CONCLUSION

The five studies meeting our inclusion criteria report a prevalence of toxoplasmosis-associated hearing loss from 0% to 26%. Improved treatment regimens for toxoplasmosis may account for this range. Three treatment groups were identified and a subgroup analysis of the compiled data was performed. In children receiving limited or no treatment, the prevalence of toxoplasmosis-associated SNHL was found to be 28%. In children prescribed 12 months of antiparasitic treatment but in whom treatment was not confirmed to have started prior to 2.5 months of age and in whom compliance was not ensured, the prevalence of SNHL was 12%. In children treated with 12 months of antiparasitical therapy initiated prior to 2.5 months of age with serologically-confirmed compliance, the prevalence of SNHL was 0%. Only two longitudinal studies were identified and neither reported any cases of delayed-onset or progressive toxoplasmosis-associated SNHL. Children who have received a 12-month course of antiparasitical therapy initiated prior to 2.5 months with serologically-confirmed compliance should have repeat audiometric evaluation at 24-30 months of age. Children with congenital toxoplasmosis that had no treatment, partial treatment, delayed onset of treatment, or compliance issues should undergo annual audiologic monitoring until able to reliably self-report hearing loss.

Objective findings with malpositioning of a nucleus 24RE(CA) cochlear implant

BACKGROUND

Proper intracochlear placement of cochlear implant electrode arrays is believed to be important for optimum speech perception results. However, objective tests of cochlear implant function typically provide little or no information about the intracochlear placement of the array. We report the results for a variety of objective tests, including averaged electrode voltage (AEV) measurements, in a patient where the electrode array had folded up on itself during insertion.

PURPOSE

To determine whether any of the objective measures provided evidence of incorrect electrode placement.

RESEARCH DESIGN

Objective test data are reported for a patient with an incorrectly positioned electrode array, prior to and following reimplantation, and compared to data obtained in 42 patients with normal insertions.

STUDY SAMPLE

One patient with an incorrectly placed electrode array, prior to and following reimplantation, and a sample of 42 implant recipients with correct insertions.

INTERVENTION

The patient with the malpositioned electrode array was explanted and reimplanted. The results for the first and the second implant, with regards to objective test results, are compared. The results are also compared to the data obtained on 42 implant recipients with normal insertions.

DATA COLLECTION AND ANALYSIS

The objective test data (primarily AEV data) are compared with AEV results obtained in 42 patients with normal electrode insertions.

RESULTS AND CONCLUSIONS

Although the electrode array had folded up on itself during insertion, intraoperative electrode impedances and VIII nerve responses, as well as postoperative electrically evoked auditory brainstem responses, were within normal limits. However, averaged electrode voltages, obtained with the Nucleus Crystal Integrity Test system, were abnormal and consistent with a low-impedance pathway between the apical and middle portions of the electrode array.

Cross-sectional survey of hearing impairment and ear disease in Uganda

OBJECTIVE

To determine the prevalence and causes of disabling hearing loss in adults and children in Uganda.

STUDY DESIGN

Cross-sectional survey of ear disease and hearing impairment.

SETTING

A random cluster sample design of the population from the Masindi district of Uganda following the World Health Organization (WHO) guidelines, using a modified version of the WHO Ear Disease Survey Protocol.

MAIN OUTCOME MEASURE

The prevalence of disabling hearing impairment using the WHO definitions (excluding 0.5 kHz owing to high background noise levels).

RESULTS

In the study, 6041 participants were enrolled and underwent audiometric evaluation and an ear examination. The prevalence of disabling hearing impairment was 11.7% in adults and 10.2% in children. A further 2.3% of children in whom thresholds could not be measured were deemed to have significant hearing loss based on screening questions and/or sound-field stimuli. Correctable causes such as dry perforations, cerumen impaction, and chronic suppurative otitis media resulted in disabling hearing loss in 17% of adult subjects and 41% of children. Preventable hearing loss, such as meningitis and noise-induced hearing loss, was present in a further significant percentage of subjects.

CONCLUSIONS

Ear disease and hearing impairment were found to be important health problems in the Ugandan population. Preventable ear disease is a major cause of hearing loss in the population. It is hoped that the findings of this study will draw attention to the problem in Uganda and will lead to proper allocation of resources for the prevention and treatment of hearing loss and ear disease.

Meta-analysis: prophylactic drainage and bleeding complications in thyroid surgery

OBJECTIVE

To conduct a comprehensive systematic review and high-quality meta-analysis to determine whether prophylactic drain placement reduces adverse bleeding events in thyroid surgery.

DATA SOURCES

MEDLINE (OVID and PubMed), CENTRAL, CDSR, ACP Journal Club, DARE, EMBASE, PREMEDLINE, OLDMEDLINE, CINAHL, BIOSIS Previews, LILACS, KOREAMED, SAMED, IndMED, SIGLE, ScienceDirect, and INGENTACONNECT.

REVIEW METHODS

Studies for evaluation included all prospective trials assessing the use of drainage in thyroid surgery. We excluded case studies, retrospective studies, reviews, and studies that had a "selective" method of postoperative drainage that was not defined or was based on surgeon preference. Search strategies were broad and based on Cochrane Collaboration search filters. There was no language restriction. Article selection was conducted by two independent reviewers under QUORUM guidelines.

RESULTS

Four hundred sixty-two articles were identified by the search strategy used, and 16 articles were included in the final review. Ten studies were randomized controlled trials, with 8 used for quantitative meta-analysis. No study showed a statistically significant benefit or harm with drain use. Meta-analysis of data estimated an odds ratio of 1.47 for reoperation for bleeding and 0.88 for visible hematoma for suction drains versus no drains. The results were not statistically significant, and 95% confidence intervals were wide.

CONCLUSION

The literature has insufficient evidence to recommend routine drainage in thyroid surgery. It is possible that drains may increase the risk of reoperation for bleeding, although the data are not statistically significant. If there is a benefit to drainage, absolute risk reductions of bleeding outcomes may not warrant routine use.

A systematic review of the incidence of sensorineural hearing loss in neonates exposed to Herpes simplex virus (HSV)

OBJECTIVE

To develop evidence-based guidelines for appropriate audiological monitoring of children born following exposure to or infection with Herpes simplex virus (HSV) for development of immediate or delayed-onset of sensorineural hearing loss (SNHL).

DATA SOURCES

A Medline search of the 1966-July 2007 database was supplemented by search of the additional database Embase (1980-July 2007). Manual search was conducted of references of identified papers and book chapters.

STUDY SELECTION

Articles were sought that were longitudinal in design, to include an inception cohort of children infected with (or exposed to) HSV who were entered at a similar point at birth and followed over time with serial audiometry to identify hearing loss if it developed.

DATA EXTRACTION

Patient information and audiometric data extraction from relevant articles was performed independently by all three researchers. Discrepancies were resolved by mutual consensus.

DATA SYNTHESIS

Data was analyzed using descriptive statistics.

RESULTS

Three papers reported five children with SNHL following apparent disseminated HSV-2 infections in which other obvious clinical sequelae of HSV infection and co-morbid conditions were present. Audiometric information is lacking regarding onset and progression. There are no reports of delayed-onset SNHL following perinatal or asymptomatic HSV infection.

CONCLUSIONS

The development of SNHL in children with exposure to HSV occurs rarely. Routine serological screening for HSV infection in otherwise healthy neonates newly diagnosed with SNHL is unjustified. There is insufficient data to define the incidence and natural history of SNHL in children with HSV infections. Carefully designed and conducted studies are needed to address this issue.

Systemic absorption of topical gentamicin sinus irrigation

OBJECTIVE

Evidence surrounding systemic absorption of gentamicin during intraoperative irrigation of the paranasal sinuses is lacking. The objectives of this study were to determine (1) if topical gentamicin is absorbed from the paranasal sinuses, (2) if hearing loss occurs following topical administration of gentamicin, and (3) if gentamicin placed within the sinuses travels retrograde (against mucociliary clearance) up the auditory tube to the middle ear.

DESIGN

Consecutive, prospective case series.

SETTING

Tertiary centre.

METHODS

A series of patients undergoing sinus surgery were identified. Fluorescein-stained gentamicin was used to irrigate the sinus cavities intraoperatively. Otoscopy using a filtered light source was performed 30 minutes postoperatively.

MAIN OUTCOME MEASURES

(1) Serum gentamicin levels preirrigation and at 30 minutes postirrigation and (2) change in pure-tone average and threshold at 8 kHz pre- and postoperative audiograms.

RESULTS

Twenty patients were enrolled. Serum gentamicin levels were detectable in three patients. Fluorescein irrigation solution was not visualized in the middle ear space. No significant hearing loss was observed in any of the patients.

CONCLUSIONS

Gentamicin may be absorbed from the nasal mucosa during intraoperative irrigation of the sinuses. However, detectable serum levels were well below therapeutic levels. The clinical significance of this finding requires further study to determine if topical sinus irrigation with gentamicin is a safe procedure.

Prevalence of new-onset vestibular symptoms following cochlear implantation

OBJECTIVE

To identify the prevalence of new-onset balance symptoms in adult patients who have undergone cochlear implantation (CI).

DESIGN

A retrospective, questionnaire-based prevalence study of 227 consecutive adults (age > 16 years) who have undergone CI. The control group comprised patients awaiting CI.

SETTING

Tertiary hospital, Vancouver, British Columbia.

METHODS

All patients implanted at the study centre were contacted. A questionnaire regarding their past medical history and the presence and character of pre- and post-CI dizziness was completed. Patients were divided into four groups based on the presence or absence of their symptoms in relation to the time of implantation. Patients with vestibular symptoms further completed the Dizziness Handicap Inventory (DHI).

MAIN OUTCOME MEASURES

Incidence of balance symptoms pre- and post-CI and associated DHI scores.

RESULTS

One hundred ten of 227 patients (48%) responded. Fifty-three (48.3%) had dizziness prior to CI and 64 patients (58.2%) postimplantation. Forty-one patients (37.3%) noted new onset of balance symptoms or a change in their symptoms post-CI. The onset was immediate (within 1 week post-CI) in the majority of this group (63.4%). DHI scores were generally low across all groups.

CONCLUSIONS

Delayed- and late-onset new balance-related symptoms occur in approximately 5 and 9% of CI patients, respectively, and the self-perceived handicapping effects of these symptoms may be greater compared with patients with symptoms prior to implantation.

Ethical considerations in resource allocation in a cochlear implant program

OBJECTIVE

To review processes of resource allocation and the ethical considerations relevant to the fair allocation of a limited number of cochlear implants to increasing numbers of potential recipients.

DESIGN

Review of relevant considerations.

SETTING

Tertiary referral hospital.

METHODS

Editorial discussion of the ethical issues of resource allocation.

MAIN OUTCOME MEASURES

Heterogeneity of audiometric thresholds, self-reported disability of hearing loss, age of the potential cochlear implant recipient, cost-effectiveness, access to resources, compliance with follow-up, social support available to the recipient, social consequences of hearing impairment, and other recipient-related factors.

RESULTS

In a publicly funded health care system, there will always be a need for decision-making processes for allocation of finite fiscal resources. All candidates for cochlear implantation deserve fair consideration. However, they are a heterogeneous group in terms of needs and expected outcomes consisting of traditional and marginal candidates, with a wide range of benefit from acoustic amplification.

CONCLUSIONS

We argue that implant programs should thoughtfully prioritize treatment on the basis of need and potential benefit. We reject queuing on the basis of "first-come, first-served" or on the basis of perceived social worth.

Natural history of hearing loss in children with enlarged vestibular aqueduct syndrome

OBJECTIVE

To determine the natural history of hearing loss in children with enlarged vestibular aqueduct (EVA) syndrome.

DESIGN

(1) Retrospective cohort study and (2) systematic literature review.

SETTING

Tertiary pediatric centre.

METHODS

(1) Charts of children assessed by one physician between 1993 and 2000 were reviewed. (2) Source articles were identified by a search of Medline, Embase, and the Cochrane Library of the English-language literature through January 2006, with manual review of references. The search was limited to English, human, and age less than 18 years.

MAIN OUTCOME MEASURES

Pure-tone average. Hearing was classified as stable, progressive and fluctuating.

RESULTS

(1) Twenty-one children (39 ears) with EVA were identified. Eighty-two percent of ears had stable hearing, and 18% of ears demonstrated progressive hearing loss. (2) Seven source articles were identified and combined with the present data for a total of 310 ears with a mean follow-up of 4 years. Bilateral EVA was found to be six times more common than unilateral EVA, and there was an equal male to female ratio. Stable hearing was found in 67% of ears and progressive hearing loss in 33% of ears. Subgroup analysis demonstrated hearing fluctuations in 50% of progressive hearing loss ears and 34% of stable ears.

CONCLUSIONS

Stable hearing is observed in 67% of ears with EVA of which 34% will demonstrate fluctuations in hearing. Progression of hearing loss is seen in 33% of ears of which half will demonstrate fluctuations.

Length of tumor–cochlear nerve contact and hearing outcome after surgery for vestibular schwannoma

Object

Tumor size is likely to be a major determinant of hearing preservation after surgery for vestibular schwannoma. Findings in some large case series have not supported this concept, possibly due to variation in the technique used for tumor measurement. The authors sought to determine if the length of tumor–cochlear nerve contact was predictive of hearing outcome in adults undergoing resection of a vestibular schwannoma.

Methods

Patients who underwent a hearing-preserving approach for resection of a vestibular schwannoma at one institution by a neurosurgeon/neurotologist team between 2001 and 2005 were screened. Patients with American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS) Class A or B hearing preoperatively were included. Magnetic resonance images were reviewed and used to calculate the length of tumor–cochlear nerve contact. Tumors were also measured according to AAO-HNS guidelines.

Results

Thirty-one patients were included, 8 (26%) of whom had hearing preservation. Univariate analysis revealed that extracanalicular length of tumor–cochlear nerve contact (p = 0.0365), preoperative hearing class (p = 0.028), I–V interpeak latency of the brainstem auditory evoked potential (p = 0.021), and the interaural I–V interpeak latency difference (p = 0.018) were predictive of hearing outcome. Multivariate analysis confirmed the predictive value of extra-canalicular length of contact and preoperative hearing class (p = 0.041 and p = 0.0235, respectively).

Conclusions

Vestibular schwannomas with greater lengths of tumor–cochlear nerve contact increase a patient's risk for hearing loss after surgery with attempted hearing preservation. Involvement of the internal auditory canal produces a constant risk of hearing loss. Data from the experience of a single surgical team can be used to estimate the probability of good hearing outcome for any given patient with serviceable hearing and a vestibular schwannoma.

Medical management of middle ear disease in children less than 2 years of age with sensorineural hearing loss

OBJECTIVE

With emerging early hearing detection and communication development programs, physicians are increasingly requested to review young children with sensorineural hearing loss (SNHL) and associated conductive hearing loss (CHL). The purpose of this critical review is to develop an evidence-based approach to the management of the child less than 2 years of age with fluctuating CHL and coexisting SNHL.

METHODS

A critical review of the 1966-2002 MEDLINE database was performed to address the diagnosis, natural history, and management of otitis media with effusion (OME) and the management of acute otitis media (AOM) in the child under 2 years of age with underlying SNHL.

RESULTS

Pneumatic otoscopy should be used to diagnose middle ear effusion. Clearance of OME may be prolonged in children with craniofacial abnormalities. Antibiotics provide a small short-term increase in the resolution of OME and may be warranted in children with coexisting SNHL and OME for 4 to 6 weeks. If OME persists for 8 to 12 weeks, bilateral myringotomy and tube placement (BM&T) with short-term tubes will improve hearing and help resolve OME. AOM in children less than 2 years of age should be treated with a 10-day course of antibiotics. Prophylactic antibiotics may be useful in avoiding tube placement in children less than 2 years of age with recurrent AOM. BM&T with short-term tubes are recommended if recurrent AOM persists. Pneumococcal vaccination can decrease episodes of AOM by 6 to 7%.

CONCLUSIONS

An evidence-based algorithm for the management of fluctuating CHL in children less than 2 years of age with an underlying SNHL is presented.