Impact of body mass index in patulous Eustachian tube: Does rapid weight loss influence symptom improvement?

OBJECTIVES: Weight loss has been proposed as risk factor for patulous Eustachian tube (PET), however, it has not been well-characterized how this subpopulation responds to standard treatments. This study aimed to evaluate PET symptom improvement in the setting of and absence of rapid weight loss. METHODS: This retrospective case series included patients diagnosed with PET at an academic institution. Demographic characteristics, medical comorbidities, presenting symptoms, treatment, and outcomes of symptom improvement were reviewed. Univariate analysis modeled the likelihood of symptom improvement between rapid weight loss and non-rapid weight loss patients. RESULTS: A total of 124 patients (median age 55 years, 61 % female) were included. At diagnosis, 7 (5.6 %) patients were underweight, 40 (32.3 %) were normal weight, 32 (25.8 %) were overweight, and 45 (36/3 %) were obese. There were 39 (31.5 %) patients who had history of weight loss prior to presentation; of these, 22 (17.7 %) noted rapid weight loss and 17 (13.7 %) had non-rapid weight loss. There were 62 (50.0 %) patients who were recommended conservative treatment, and 62 (50.0 %) who underwent medical and/or surgical treatment. Symptom resolution was achieved in 49 (39.5 %) patients. On univariate analysis, patients with rapid weight loss were significantly more likely to experience improvement (p = 0.006) than non-rapid weight loss. Rapid weight loss patients had a four-fold increased likelihood of symptom improvement compared to non-rapid weight loss patients (OR = 4.8, p = 0.053). CONCLUSIONS: While rapid weight loss and bariatric surgery are reported risk factors for the development of PET, our findings suggest that patients with rapid weight loss are significantly more likely to achieve symptom improvement than non-rapid weight loss.

Predictive Modeling and Risk Stratification of Patients With Enlarged Vestibular Aqueduct.

OBJECTIVES/HYPOTHESIS: To investigate patient-specific characteristics that independently predict for progressive hearing loss in patients with enlarged vestibular aqueduct (EVA). Utilize multivariable predictive models to identify subgroups of patients with significantly different progression risks. STUDY DESIGN: Retrospective analysis of patients evaluated at an academic tertiary care center. Cohort included 74 ears of patients with a diagnosis of EVA as defined by the Cincinnati criteria. METHODS: Hearing trajectories were characterized, and a Kaplan-Meier estimator was utilized to determine progressive phenotype probabilities across the first 10 years after diagnosis. Cox proportional hazard regression was used to identify patient characteristics that independently altered this probability. Stratified risk groups were delineated from generated nomogram scores. RESULTS: Male gender was associated with a 4.53 hazard ratio for progressive hearing loss (95% confidence interval [CI], 2.53 to 12.59). Each millimeter increase in operculum size was independently associated with an 80.40% increase in expected hazard (95% CI, 40.18 to 120.62). Each dB increase in air pure tone average at time of diagnosis decreased expected hazard by 1.59% (95% CI, -3.02 to -0.17). The presence of incomplete partition type II was associated with a 2.44 hazard ratio (95% CI, 1.04 to 5.72). Risk groups stratified by median nomogram score evidenced the discriminative ability of our model with the progression probability in the high-risk group being six times higher at 1 year, nearly five times greater at 3 years, and three times greater at 9 years. CONCLUSIONS: EVA patient characteristics can be used to predict hearing loss probability with a high degree of accuracy (C-index of 0.79). This can help clinicians make more proactive management decisions by identifying patients at high risk for hearing loss. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:1439-1445, 2022.

Cochlear Implantation in Patients With Menière's Disease: Does Disease Activity Affect the Outcome?

OBJECTIVE: Menière's disease (MD) is characterized by episodes of vertigo, tinnitus, and sensorineural hearing loss. In the setting of bilateral deafness due to MD alone or contralateral pathology, cochlear implantation (CI) improves hearing. Active MD is characterized by fluctuating auditory symptoms and vertigo; whereas remittance of vertiginous symptoms and severe, permanent sensorineural hearing loss characterizes the inactive disease state. This study evaluates outcomes for MD patients compared with the general CI population and assesses if disease activity affects implant outcomes. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: Twenty-four patients with MD that received CI (7 active, 16 inactive, and 1 Probable Menière's), and 24 age-matched controls. INTERVENTIONS: Cochlear implantation. MAIN OUTCOME MEASURES: Word Recognition Score, Sentence Recognition Score (SRS), and Speech Reception Threshold. RESULTS: Best-aided preoperative and postoperative audiometric data were compared per ear between MD patients and controls and stratified by disease status using descriptive statistics with mixed-effects modeling. Patients with MD derived significantly more benefit from CI than controls when comparing differences between preoperative and postoperative levels for Word Recognition Score (12.2%, p = 0.0236), SRS (12.8%, p = 0.0375), and Speech Reception Threshold (-14.4 dB, p = 0.0188). Active disease status does not negatively impact CI outcomes and patients with active MD may benefit from greater gains in SRS (23.5%, p = 0.0107). CONCLUSIONS: CI provides greater gains in functional hearing for patients with MD compared with age-matched controls. Patients with active MD seem to perform better with respect to SRS following CI than patients with inactive status.

Morphology and cochlear implantation in enlarged vestibular aqueduct.

PURPOSE: The purpose of this work is to explore audiometry following cochlear implantation (CI) in patients with enlarged vestibular aqueduct (EVA) and to investigate the effects of inner ear morphological variation on post CI audiometry. METHODS: This was a retrospective review of both natural and cochlear-implant-aided audiometry results, using all available measurements in a mixed-effects model accounting for longitudinal change and the grouping structure of ears. Patients who visited our tertiary academic medical center between 2000 and 2016 were identified as having EVA according to Cincinnati criteria on radiological examination; patients eligible for CI were then selected for analysis. RESULTS: Multivariable modeling showed a statistically significant hearing improvement in ears with EVA undergoing CI with regards to pure tone average (-64.0 dB, p < 0.0001), speech reception threshold (-57.90 dB, p < 0.0001), and word score (34.8%, p > 0.0001). Vestibular aqueduct midpoint size and the presence of incomplete partition type II (IP II) did not have significant independent associations with audiometric findings. However, multivariable modeling revealed a statistically significant interaction between IP II and CI such that IP II ears demonstrated a decrease in WS improvement of 30.2% (p = 0.0059) compared to non-IP II ears receiving CI. CONCLUSION: There is a statistically significant audiometric benefit to ears with EVA receiving CI. Morphology, specifically the presence of IP II, may hinder CI benefit in terms of word score however this finding needs clinical validation. This data improves personalization of surgical counseling and planning for patients with EVA considering CI.

Jugular bulb and skull base pathologies: proposal for a novel classification system for jugular bulb positions and microsurgical implications.

OBJECTIVE There is no definitive or consensus classification system for the jugular bulb position that can be uniformly communicated between a radiologist, neurootologist, and neurosurgeon. A high-riding jugular bulb (HRJB) has been variably defined as a jugular bulb that rises to or above the level of the basal turn of the cochlea, within 2 mm of the internal auditory canal (IAC), or to the level of the superior tympanic annulus. Overall, there is a seeming lack of consensus, especially when MRI and/or CT are used for jugular bulb evaluation without a dedicated imaging study of the venous anatomy such as digital subtraction angiography or CT or MR venography. METHODS A PubMed analysis of "jugular bulb" comprised of 1264 relevant articles were selected and analyzed specifically for an HRJB. A novel classification system based on preliminary skull base imaging using CT is proposed by the authors for conveying the anatomical location of the jugular bulb. This new classification includes the following types: type 1, no bulb; type 2, below the inferior margin of the posterior semicircular canal (SCC), subclassified as type 2a (without dehiscence into the middle ear) or type 2b (with dehiscence into the middle ear); type 3, between the inferior margin of the posterior SCC and the inferior margin of the IAC, subclassified as type 3a (without dehiscence into the middle ear) and type 3b (with dehiscence into the middle ear); type 4, above the inferior margin of the IAC, subclassified as type 4a (without dehiscence into the IAC) and type 4b (with dehiscence into the IAC); and type 5, combination of dehiscences. Appropriate CT and MR images of the skull base were selected to validate the criteria and further demonstrated using 3D reconstruction of DICOM files. The microsurgical significance of the proposed classification is evaluated with reference to specific skull base/posterior fossa pathologies. RESULTS The authors validated the role of a novel classification of jugular bulb location that can help effective communication between providers treating skull base lesions. Effective utilization of the above grading system can help plan surgical procedures and anticipate complications. CONCLUSIONS The authors have proposed a novel anatomical/radiological classification system for jugular bulb location with respect to surgical implications. This classification can help surgeons in complication avoidance and management when addressing HRJBs.

Hearing loss in enlarged vestibular aqueduct and incomplete partition type II.

PURPOSE: The purpose of this work is to identify the role of incomplete partition type II on hearing loss among patients with enlarged vestibular aqueduct (EVA). BACKGROUND: EVA is a common congenital inner ear malformation among children with hearing loss, where vestibular aqueduct morphology in this population has been shown to correlate to hearing loss. However, the impact of incomplete partition between cochlear turns on hearing loss has not been, despite meaningful implications for EVA pathophysiology. METHODS: A retrospective review of radiology reports for patients who had computed tomography (CT) scans with diagnoses of hearing loss at a tertiary medical center between January 2000 and June 2016 were screened for EVA. CT scans of the internal auditory canal (IAC) for those patients with EVA were examined for evidence of incomplete partition type II (IP-II), measurements of midpoint width and operculum width a second time, and patients meeting Cincinnati criteria for EVA selected for analysis. Statistical analysis including chi-square, Wilcoxon rank-sum, and t-tests were used to identify differences in outcomes and clinical predictors, as appropriate for the distribution of the data. Linear mixed models of hearing test results for all available tests were constructed, both univariable and adjusting for vestibular aqueduct morphometric features, with ear-specific intercepts and slopes over time. RESULTS: There were no statistically significant differences in any hearing test results or vestibular aqueduct midpoint and operculum widths. Linear mixed models, both univariable and those adjusting for midpoint and operculum widths, did not indicate a statistically significant effect of incomplete partition type II on hearing test results. CONCLUSIONS: Hearing loss due to enlarged vestibular aqueduct does not appear to be affected by the presence of incomplete partition type II. Our results suggest that the pathophysiological processes underlying hearing loss in enlarged vestibular aqueduct may not be a result of cochlear malformation, and instead are more likely to involve vestibular aqueduct or cellular and molecular-level mechanisms of hearing loss.

Vestibular Aqueduct Midpoint Width and Hearing Loss in Patients With an Enlarged Vestibular Aqueduct.

Importance: Elucidating the relationship between vestibular aqueduct size and hearing loss progression may inform the prognosis and counseling of patients who have an enlarged vestibular aqueduct (EVA). Objectives: To examine the association between vestibular aqueduct size and repeated measures of hearing loss. Design, Setting, and Participants: For this retrospective medical record review, 52 patients with a diagnosis of hearing loss and radiologic diagnosis of EVA according to the Valvassori criterion were included. All available speech reception threshold and word recognition score data was retrieved; mixed-effects models were constructed where vestibular aqueduct size, age at diagnosis of hearing loss, and time since diagnosis of hearing loss were used to predict repeated measures of hearing ability. This study was performed at an academic tertiary care center. Exposures: Variable vestibular aqueduct size, age at first audiogram, length of time after first audiogram. Main Outcomes and Measures: Speech reception threshold (dB) and word recognition score (%) during routine audiogram. Results: Overall, 52 patients were identified (29 females [56%] and 23 males [44%]; median age at all recorded audiograms, 7.8 years) with a total of 74 ears affected by EVA. Median (range) vestibular aqueduct size was 2.15 (1.5-5.9) mm, and a median (range) of 5 (1-18) tests were available for each patient. Each millimeter increase in vestibular aqueduct size above 1.5 mm was associated with an increase of 17.5 dB in speech reception threshold (95% CI, 7.2 to 27.9 dB) and a decrease of 21% in word recognition score (95% CI, -33.3 to -8.0 dB). For each extra year after a patient's first audiogram, there was an increase of 1.5 dB in speech recognition threshold (95% CI, 0.22 to 3.0 dB) and a decrease of 1.7% in word recognition score (95% CI, -3.08 to -0.22 dB). Conclusions and Relevance: Hearing loss in patients with an EVA is likely influenced by vestibular aqueduct midpoint width. When considering hearing loss prognosis, vestibular aqueduct midpoint width may be useful for the clinician who counsels patients affected by EVA.

Long-term outcomes of endolymphatic sac shunting with local steroids for Meniere's disease.

OBJECTIVES: To evaluate the long-term efficacy of endolymphatic sac shunt techniques with and without local steroid administration. STUDY DESIGN: Retrospective case series and patient survey. SETTING: Tertiary university hospital. PATIENTS: Meniere's disease (MD) patients that failed medical therapy and subsequently underwent an endolymphatic sac shunt procedure. All patients had definitive or probable MD and at least 18-months of follow-up. INTERVENTIONS: Three variations on endolymphatic sac decompression with shunt placement were performed: Group A received no local steroids, Group B received intratympanic dexamethasone prior to incision, and Group C received dexamethasone via both intratympanic injection and direct endolymphatic sac instillation. MAIN OUTCOME MEASURE(S): Vertigo control, hearing results, and survey responses. RESULTS: Between 2002 and 2013, 124 patients with MD underwent endolymphatic sac decompression with shunt placement. 53 patients met inclusion criteria. Groups A, B, and C had 6 patients, 20 patients, and 27 patients, respectively. Mean follow-up was 56months. Vertigo control improved in 66%, 83%, and 93% of Groups A, B, and C. Functional level improved for Group B (-2.0) and Group C (-2.2) but was unchanged in Group A. Pure-tone average and speech discrimination scores changed by +22dB and -30%, +6dB and -13%, and +6dB and -5% in Groups A, B, and C. The long-term hearing results were significantly better with steroids (Groups B and C) according to the AAO-HNS 1995 criteria but did not meet significance on non-parametric testing. CONCLUSIONS: Endolymphatic sac shunt procedures may benefit from steroid instillation at the time of shunt placement.

Successful endovascular management of venous sinus thrombosis complicating trans-labyrinthine removal of vestibular schwanomma.

Cerebral venous sinus thrombosis (CVST) is a rare complication of surgical treatment of vestibular schwanomma. We present a rare case of extensive venous sinus thrombosis after trans-labyrinthine approach that was refractory to systemic anti-coagulation. Mechanical aspiration thrombectomy was utilized to re-canalize the venous sinuses and resulted in successful resolution of neurological symptoms. Indications of utilizing endovascular approaches are discussed that will enable skull base surgeons to address this uncommon yet potentially fatal complication.

Bilateral Sequential Cochlear Implantation in Patients With Enlarged Vestibular Aqueduct (EVA) Syndrome.

OBJECTIVES: To analyze audiometric outcomes after bilateral cochlear implantation in patients with isolated enlarged vestibular aqueduct (EVA) syndrome and associated incomplete partition (IP) malformations. Secondary objective was to analyze rate of cerebrospinal fluid (CSF) gusher in patients with IP-EVA spectrum deformities and compare this with the existing literature. STUDY DESIGN: Retrospective chart review. METHODS: Thirty-two patients with EVA syndrome who received unilateral or bilateral cochlear implants between June 1999 and January 2014 were identified in the University Hospitals Case Medical Center cochlear implant database. Isolated EVA (IEVA) and Incomplete Partition Type II (IP-II) malformations were identified by reviewing high-resolution computed tomography (HRCT) imaging. Demographic information, age at implantation, surgical details, postimplantation audiometric data including speech reception thresholds (SRT), word, and sentence scores were reviewed and analyzed. Intra- and postoperative complications were analyzed as well and compared with the literature. RESULTS: Seventeen patients (32 implanted ears) had pediatric cochlear implantation for EVA-associated hearing loss. Data from 16 controls (32 implanted ears) were used to compare audiometric and speech outcomes of EVA cohort. Mean age at implantation was 6.8 years for EVA cohort and 6.0 years for controls. There was no statistically significant difference in long-term postoperative SRT, monaurally aided word scores, and binaurally tested word scores between pediatric EVA group and controls. The EVA patients had a long-term mean sentence score of 85.92%. A subset of EVA patients implanted at mean age of 3.18 years (n = 15 ears) had similar audiometric outcomes to another control group with Connexin 26 mutations (n = 20 ears) implanted at a similar age. Further subset analysis revealed no significant differences in age at implantation, SRT, and word scores in patients with IEVA and IP-II malformation. There was no significant association between size of vestibular aqueduct and age at implantation. There was no CSF gusher or other intra- or postoperative complications reported in our series. CONCLUSION: Bilateral sequential cochlear implantation can be performed safely in patients with EVA. Audiometric outcomes are excellent and comparable to pediatric cochlear implant patients with no malformations. CSF gusher rates can be minimized by trans-round window approach. Further long-term studies are needed to identify differences within IP-EVA spectrum deformities, audiometric outcomes, and proportions of EVA patients who will need cochlear implantation for hearing rehabilitation.

Retrosigmoid versus translabyrinthine approach to acoustic neuroma resection: A comparative cost-effectiveness analysis.

OBJECTIVES/HYPOTHESIS: Approach-specific economic data of acoustic neuroma (AN) resection is lacking. The purpose of this study was to analyze and compare adjusted total hospital costs, hospital and intensive care unit (ICU) length of stay (LOS), and associated factors in AN patients undergoing resection by translabyrinthine (TL) approach versus retrosigmoid (RS) approach. STUDY DESIGN: Retrospective chart review. METHODS: A total of 113 patients with AN undergoing TL (N = 43) or RS (N = 70) surgical resection between 1999 and 2012 were analyzed. Data including age, health status, preoperative hearing, tumor size, postoperative complications, hospital, ICU LOS, and disposition after discharge were collected from medical records and compared between both groups. Cost data was obtained from the hospital finance department and adjusted based on the Consumer Price Index for 2013. RESULTS: There were no significant differences in demographic data, preoperative hearing, preoperative health status, or postoperative complication rate. Total hospital LOS and ICU LOS were significantly longer in the RS compared to the TL group (4.3 ± 3.6 vs. 2.6 ± 1.1 days; P < 0.001, and 1.5 ± 1.1 vs. 1.0 ± 0.5 days; P = 0.015, respectively). Tumors were larger in RS compared to the TL group (2.1 ± 1.0 cm vs. 1.5 ± 0.7 cm, respectively; P = 0.002). When patients were stratified by tumor size < or ≥ 2 cm, the total hospital LOS remained greater in the RS group in both subgroups (< and ≥ 2 cm, P < 0.001, and P = 0.031, respectively). However, there was no difference in the total ICU LOS between both subgroups. The adjusted mean total hospital cost was higher in the RS compared to the TL group ($25,069 ± 14,968 vs. $16,799 ± 5,724; P < 0.001). The adjusted mean total hospital cost was greater in the RS group with tumor < 2 cm (P < 0.001) but not significantly different in patients with tumors ≥ 2 cm. Univariate analysis showed that greater tumor size, poorer preoperative health status, the presence of major postoperative complications, and the RS approach were independently significantly associated with higher total hospital LOS (P = 0.001, P = 0.009, P = 0.001, and P < 0.001, respectively) and a higher adjusted total hospital cost (P < 0.001, P = 0.002, P = 0.014, and P < 0.001, respectively). CONCLUSION: Hospital LOS and total adjusted costs are significantly less for patients undergoing translabyrinthine acoustic neuroma resection compared to the retrosigmoid approach. Many factors appear to influence these differences. Economic considerations in addition to tumor characteristics and surgeon preference should be considered in future acoustic neuroma resections. LEVEL OF EVIDENCE: 2c.

Deep Brain Stimulation of Heschl Gyrus: Implantation Technique, Intraoperative Localization, and Effects of Stimulation.

BACKGROUND: Tinnitus is a source of considerable morbidity, and neuromodulation has been shown to be a potential treatment option. However, the location of the primary auditory cortex within Heschl gyrus in the temporal operculum presents challenges for targeting and electrode implantation. OBJECTIVE: To determine whether anatomic targeting with intraoperative verification using evoked potentials can be used to implant electrodes directly into the Heschl gyrus (HG). METHODS: Nine patients undergoing stereo-electroencephalogram evaluation for epilepsy were enrolled. HG was directly targeted on volumetric magnetic resonance imaging, and framed stereotaxy was used to implant an electrode parallel to the axis of the gyrus by using an oblique anterolateral-posteromedial trajectory. Intraoperative evoked potentials from auditory stimuli were recorded from multiple electrode contacts. Postoperatively, stimulation of each electrode was performed and participants were asked to describe the percept. Audiometric analysis was performed for 2 participants during subthreshold stimulation. RESULTS: Sounds presented to the contralateral and ipsilateral ears produced evoked potentials in HG electrodes in all participants intraoperatively. Stimulation produced a reproducible sensation of sound in all participants with perceived volume proportional to amplitude. Four participants reported distinct sounds when different electrodes were stimulated, with more medial contacts producing tones perceived as higher in pitch. Stimulation was not associated with adverse audiometric effects. There were no complications of electrode implantation. CONCLUSION: Direct anatomic targeting with physiological verification can be used to implant electrodes directly into primary auditory cortex. If deep brain stimulation proves effective for intractable tinnitus, this technique may be useful to assist with electrode implantation. ABBREVIATIONS: DBS, deep brain stimulatorEEG, electroencephalographyHG, Heschl gyrus.

Ipsilateral single stage conversion from BAHA to cochlear implant.

Profound unilateral sensorineural hearing loss is an indication for the placement of a bone anchored hearing aid. In a few unfortunate patients who later develop contralateral hearing loss, a cochlear implant becomes a good option. We present our experience in these cases and discuss our technique for single stage conversion from a bone anchored hearing aid to a cochlear implant.

Endolymphatic sac tumors.

Endolymphatic sac tumors (ELST) are slow-growing, locally aggressive, low-grade malignancies that originate from the epithelium of the endolymphatic duct and sac. ELST often present with sensorineural hearing loss, tinnitus, and vertigo, which may mimic Meniere disease. Large tumors may present with additional cranial neuropathies. Management is primarily via microsurgical excision. Radiation therapy has a limited role for residual or unresectable disease. Early detection may enable hearing preservation techniques. ELST have an association with von Hippel-Lindau disease.

Predictive factors and outcomes of cochlear implantation in patients with connexin 26 mutation: a comparative study.

PURPOSE: To compare hearing outcomes in patients with connexin 26 (Cx 26) mutations undergoing cochlear implantation to age matched controls and to examine whether age at implantation, gender and type of mutation were correlated with hearing outcome. MATERIALS AND METHODS: Retrospective chart review of 21 patients with Cx 26 mutations that underwent cochlear implantation compared to 18 age-matched controls. Patients' characteristics, type of mutation and pre- and postoperative short and long-term hearing thresholds, word and sentence scores were analyzed. RESULTS: There was no statistically significant difference between the Cx 26 and control group in the mean short term and mean long term post-operative pure tone averages (PTA), speech reception thresholds (SRT), word and sentence scores. Gender, age at implantation and type of connexin 26 mutation did not predict hearing outcomes. CONCLUSIONS: In patients with connexin 26 mutation, cochlear implantation provides an effective mean of auditory habilitation. Mutational status, age and gender do not seem to predict hearing outcomes.

A Genetic Murine Model of Endolymphatic Hydrops: The Phex Mouse.

Animal models of endolymphatic hydrops (ELH) provide critical insight into the pathophysiology of Meniere's disease (MD). A new genetic murine model, called the Phex mouse, circumvents prior need for a time and cost-intensive surgical procedure to create ELH. The Phex mouse model of ELH, which also has X-linked hypophosphatemic rickets, creates a postnatal, spontaneous, and progressive ELH whose phenotype has a predictable decline of vestibular and hearing function reminiscent of human MD. The Phex mouse enables real-time histopathologic analysis to assess diagnostic and therapeutic interventions as well as further our understanding of ELH's adverse effects. Already the model has validated electrocochleography and cervical vestibular evoked myogenic potential as useful diagnostic tools. New data on caspase activity in apoptosis of the spiral ganglion neurons may help target future therapeutic interventions. This paper highlights the development of the Phex mouse model and highlights its role in characterizing ELH.

Conservative management of vestibular schwannoma: expectations based on the length of the observation period.

OBJECTIVE: Evaluate long-term prevalence of tumor growth and need for further treatment in patients with a vestibular schwannoma treated with conservative management. STUDY DESIGN: Retrospective chart review. SETTING: Private neurotologic tertiary referral center. PATIENTS: Vestibular schwannoma patients undergoing conservative management and previously studied (N = 114). Mean time to last magnetic resonance imaging was 4.8 years and to last follow-up was 6.4 years (maximum, 18.5 yr). INTERVENTION: Serial gadolinium-enhanced magnetic resonance imaging with size measurement. MAIN OUTCOME MEASURES: Change in maximum tumor dimension of 2 mm or higher (growth), further treatment, audiologic measures-pure-tone average, word recognition, AAO-HNS (American Academy of Otolaryngology-Head and Neck Surgery) hearing class. RESULTS: Thirty-eight percent of tumors demonstrated growth; an average of 6.5 mm (SD, 3.8) at a mean rate of 3.1 mm per year. Of patients with no growth at 1 year or less, 20% grew by last follow-up. Overall, 31% had further treatment after a mean of 3.8 years (SD, 3.5; maximum, 18.5 yr). Of those followed for 5 to 10 years, 18% eventually had further treatment. Only 56% of growing tumors had further treatment by last follow-up; 14.8% with nongrowing tumors also had further treatment. Pure-tone average declined more in tumors that grew (mean Δ = 28.8 dB) than those that did not (mean Δ = 16.5 dB) (p ≤ 0.025), but there was no correlation between the amount of change in hearing and in the size of the tumor. Of patients with an initial AAO-HNS hearing Class A, 85.7% retained serviceable hearing. CONCLUSION: For patients electing an observation approach to treatment of vestibular schwannoma, about 31% may eventually undergo further treatment. Of those followed for 5 to 10 years, 18% eventually had further treatment. However, some patients are followed with radiologic evaluations for many years without necessity for further treatment.

A mouse model validates the utility of electrocochleography in verifying endolymphatic hydrops.

Endolymphatic hydrops (ELH) is a disorder of the inner ear that causes tinnitus, vertigo, and hearing loss. An elevated ratio of the summating potential (SP) to the action potential (AP) measured by electrocochleography has long been considered to be the electrophysiological correlate of ELH-related clinical conditions, such as Meniere's disease, but in vivo confirmation and correlation between an elevated SP/AP ratio and ELH has not yet been possible. Confirming this relationship will be important to show that elevated SP/AP ratio is indeed diagnostic of ELH. Here, we sought to confirm that an elevated SP/AP ratio is associated with ELH and test the hypothesis that severity of ELH and hearing loss would also correlate with the SP/AP ratio in vivo using the Phex(Hyp-Duk)/Y mouse model of postnatal ELH. In addition, we describe a minimally invasive approach for electrocochleography in mice. Auditory brainstem responses and electrocochleography data were collected from controls and Phex(Hyp-Duk)/Y mutants at postnatal day 21 and the mice (all male) were euthanized immediately for cochlear histology. Our results show that (1) the SP/AP ratio was significantly elevated in mice with histological ELH compared to controls, (2) the SP/AP ratio was not correlated with the severity of histological ELH or hearing loss, and (3) the severity of hearing loss correlated with the severity of histological ELH. Our study demonstrates that an elevated SP/AP ratio is diagnostic of ELH and that the severity of hearing loss is a better predictor of the severity of ELH than is the SP/AP ratio.

Hearing and vertigo outcomes after congenital labyrinthine cholesteatoma resection.

Congenital labyrinthine cholesteatoma can cause varying degrees of hearing loss and vertigo. Hearing preservation is not always possible when treatment involves total labyrinthectomy. Since 1969, there have been several case reports and case series documenting hearing preservation following surgical treatment of congenital labyrinthine cholesteatoma. However, none of the case reports or case series documents the patients' vestibular complaints after surgery. Herein, we report a case series of four patients who were treated with the goal of hearing preservation and resolution of vertigo after partial or complete removal of the bony labyrinth for congenital inner ear cholesteatoma. We will also discuss possible explanations for the mechanisms of preservation of hearing and vestibular function with a review of the current literature.