Cochlear Implantation for Patients with a Vestibular Schwannoma: Effect on Tinnitus Handicap.

BACKGROUND: Tinnitus is a common symptom among individuals with a vestibular schwannoma. In recent years, cochlear implantation, often combined with tumor resection, is an increasingly used option in the management of these patients. The existing literature does not account well for the effect of treatment on tinnitus burden. Thus, this paper reports the effect of cochlear implantation on tinnitus in a cohort of vestibular schwannoma patients. METHODS: Individuals with vestibular schwannoma undergoing cochlear implantation were retrospectively reviewed for tinnitus burden, as evaluated by the Tinnitus Handicap Inventory, administered before and after implantation. The outcome measures were total Tinnitus Handicap Inventory score and scores from each of the Tinnitus Handicap Inventory subdomains (functional, emotional, and catastrophic). In addition, the existing literature on tinnitus in cochlear implanted vestibular schwannoma patients was reviewed. RESULTS: Tumor management consisted of simultaneous resection (77%), previous resection (9%), observation (9%) and radiation (5%). Complete Tinnitus Handicap Inventory evaluation was available for 17 patients. After implantation, the median THItotal changed from 18 to 10 (P = .0006), the subdomain THIfunctional from 10 to 3 (P = .006), the THIemotional from 3 to 0 (P = .023) and the THIcatastrophic from 6 to 1 (P = .004). In the scarcely reported tinnitus outcomes in the literature, most but not all cases experienced a decrease in tinnitus. CONCLUSIONS: The tinnitus burden is significantly reduced by cochlear implantation in individuals with a vestibular schwannoma. This agrees with findings for other etiologies indicating cochlear implantation and supports the eligibility for hearing rehabilitation with a cochlear implant for this specific group of patients.

Functional Loss After Meningitis-Evaluation of Vestibular Function in Patients With Postmeningitic Hearing Loss.

Introduction: The inner ear vestibular system is essential to balance function. Although hearing loss is well-described and quite common following meningitis, the literature evaluating vestibular function following meningitis is very limited. In particular, information on results of contemporary vestibular function tests, e.g., the video head impulse test (VHIT), is scarce. Using contemporary vestibular function tests, this study examines the vestibular function of patients with profound hearing loss (HL) after meningitis. Methods: Review of the literature and retrospective controlled study. Patients: Twenty-one consecutive patients with profound HL after meningitis (cochlear implant candidates) matched with 20 patients with profound HL of unknown etiology and examined during the period 2013-2018. Outcome Measure: Vestibular function loss, as evaluated with VHIT vestibulo-ocular reflex (VOR) gain, eye movement saccades, and cervical vestibular-evoked myogenic potentials (cVEMPs). The results of these tests were correlated to inner ear imaging findings (MRI/CT) and the level of hearing loss. Results: Mean VHIT gain was 0.48 in the meningitis group compared to 0.86 in the control group (p < 0.01). Saccades were present in 21 ears (62%) in the meningitis group compared to six ears (15%) among the controls (p < 0.01). cVEMP responses were present on five ears (18%) in the meningitis group and 25 ears (66%) in the control group (p < 0.01). Discussion: Postmeningitic hearing loss is associated with poor vestibular function, as evaluated by VHIT, saccades, and cVEMP. Loss of vestibular function correlates with the degree of hearing loss and inner ear imaging findings, although not in all cases. Vestibular function should be examined in patients surviving meningitis with hearing loss in order to individualize rehabilitation and improve balance outcome.

Video Head Impulse Test Results in Patients With a Vestibular Schwannoma-Sensitivity and Correlation With Other Vestibular System Function Tests, Hearing Acuity, and Tumor Size.

OBJECTIVE: No previous studies have investigated a vestibular function test battery combining the Video Head Impulse Test (VHIT), the caloric test, and the cervical vestibular evoked myogenic potential (cVEMP) test. The objective was to investigate the sensitivity of the three vestibular tests to the presence of a vestibular schwannomas (VS), and possible correlations between test results, hearing acuity, and tumor size. STUDY DESIGN: Retrospective cohort study. SETTING: University hospital. PATIENTS: Fifty-nine patients with a unilateral VS. INTERVENTION: Audio-vestibular tests; the VHIT, cVEMP, caloric irrigation, pure-tone audiometry, and speech discrimination. MAIN OUTCOME MEASURE: Findings, sensitivity, and correlations between VHIT saccades and gain; cVEMP potentials, unilateral caloric weakness; hearing acuity. RESULTS: The sensitivity for VS was 80% for the VHIT, 93% for the caloric test, and 73% for the cVEMP test. VHIT gain and saccades were associated, and both had a positive correlation to caloric function. Medium-sized tumors demonstrated the highest gain asymmetry while larger tumors were associated with saccades. There was a weak correlation between vestibular findings and hearing acuity. CONCLUSION: The VHIT is sensitive to the occurrence of a VS, but less so than the caloric test, and vestibular function deteriorates to some extent with increasing tumor size. VHIT outcomes are positively correlated to caloric function, but only vaguely to cVEMP and hearing acuity. The combined vestibular function test battery reached a sensitivity of 97% to the occurrence of a VS and could thus potentially substitute MRI for tumor screening upon the diagnosis of an asymmetrical hearing loss.

Tumor miRNA expression profile is related to vestibular schwannoma growth rate.

OBJECTIVE: Our objective was to investigate if the tumor microRNA (miRNA) expression profile was related to tumor growth rate. Growth-related miRNAs might be potential targets for future therapeutic intervention. MATERIAL AND METHODS: Tumor tissue was sampled during surgery of patients with a sporadic vestibular schwannoma. Tumor growth rate was determined by tumor measurement on the two latest pre-operative MRI scans. Tumor miRNA expression was analyzed using the Affymetrix Gene Chip® protocol, and CEL files were generated using GeneChip® Command Console® Software and normalized using Partek Genomics Suite 6.5. The CEL files were analyzed using the statistical software program R. Principal component analysis, affected gene ontology analysis, and analysis of miRNA expression fold changes were used for analysis of potential relations between miRNA expression profile and tumor growth rate. RESULTS AND CONCLUSION: Tumor miRNA expression is related to the growth rate of sporadic vestibular schwannomas. Rapid tumor growth is associated with deregulation of several miRNAs, including upregulation of miR-29abc, miR-19, miR-340-5p, miR-21, and miR-221 and downregulation of miR-744 and let-7b. Gene ontologies affected by the deregulated miRNAs included neuron development and differentiation, gene silencing, and negative regulation of various biological processes, including cellular and intracellular signaling and metabolism.

Sporadic and NF2-associated vestibular schwannoma surgery and simultaneous cochlear implantation: a comparative systematic review.

PURPOSE: Cochlear implantation (CI) in patients with sensorineural hearing loss caused by a vestibular schwannoma (VS) represents a unique subtype of hearing rehabilitation, as the outcome may be compromised by vestibulocochlear nerve injury as part of the natural VS history or due to iatrogenic trauma induced by surgical tumor removal. This paper aims to review and report contemporary knowledge and practice regarding feasibility and outcomes of simultaneous vestibular schwannoma resection and cochlear implantation to serve as a reference and guide for future surgery and studies. METHODS: The current literature was searched systematically according to the PRISMA guidelines and after criteria-based selection, 29 studies were identified, including a total of 86 patients who had undergone surgical resection of a vestibular schwannoma and subsequent cochlear implantation in a single procedure. RESULTS: The postoperative outcomes were reported with a high degree of heterogeneity, hindering a proper meta-analysis. However, pooling those cases with reported speech discrimination outcomes demonstrated mean scores equivalent to moderate-to-high performance. A few cases had no audibility. A positive cochlear nerve test result was not a secure positive predictor of success. Complications were rare. CONCLUSION: NF2-associated and sporadic VS had good and comparable postoperative outcomes despite significant differences in tumor size, location and surgical approach.

[Bone-anchored hearing aids and active middle ear implants].

This review is concerned with hearing implants, which are used in patients with hearing loss, who cannot be treated successfully with a conventional hearing aid. Among these implants, bone-anchored hearing systems (BAHS) can be used for conductive or mixed hearing loss, while active middle ear implants primarily are reserved for sensorineural hearing loss. For BAHS, active transcutaneous implants may replace percutaneous implants as a future first choice.

Cochlear MRI Signal Change Following Vestibular Schwannoma Resection Depends on Surgical Approach.

OBJECTIVE: Information on cochlear MRI signal change following vestibular schwannoma (VS) surgery by the retrolabyrinthine approach (RLA) is nonexisting, and information using the translabyrinthine approach (TLA) is scarce. We aimed to evaluate cochlear MRI fluid signal in patients with a unilateral VS, before and after surgery by the RLA or the TLA, that can have clinical importance for subsequent cochlear implantation feasibility. STUDY DESIGN: Retrospective cohort study. SETTING: University hospital. PATIENTS: One hundred one patients with a unilateral VS. INTERVENTION: VS resection by the TLA or the RLA. Pre- and postoperative T2-weighted MRI. MAIN OUTCOME MEASURE: Cochlear signal change using a semiquantitative system for grading cochlear asymmetry, with grades ranging from 1 (normal fluid signal both sides) to 4 (no fluid signal one side). RESULTS: Seventy-four patients were operated by the TLA and 27 by the RLA. The number of cochleas with grade 3 and 4 asymmetries postoperative was significantly higher than preoperative. The postoperative proportions of grade 1 (TLA 20%, RLA 56%) and grade 2-4 asymmetry (TLA 80%, RLA 44%) were significantly different between the two groups. In the TLA group, 46 patients (62%) demonstrated an increased asymmetry postoperatively, as compared with three patients (11%) in the RLA group. CONCLUSIONS: Postoperative decrease of cochlear MRI fluid signal is more likely to occur after translabyrinthine surgery (occurring in 62%), as compared with retrolabyrinthine surgery (occurring in 11%). The decrease of cochlear signal may be due to compromised vascularity or fibrosis.

Simultaneous Contralateral Vestibular Schwannoma and Glomus Tumor of the Temporal Bone- A Case Report.

INTRODUCTION: Presence of vestibular schwannoma and a simultaneous glomus jugulare tumor is an extremely rare event. There is only one case report regarding the incidence of a contralateral vestibular schwannoma, along with a glomus jugulare tumor. Herein, we present the second case with a contralateral tumor. CASE REPORT: A 69-year-old woman presented with a long history of bilateral hearing loss and a 2-year history of left-sided pulsatile tinnitus. The patient also suffered the itching of the left ear canal and mild vertigo; however, she had no recollection of middle ear infection, ear discharge, or ear pain. Magnetic resonance imaging (MRI) revealed a right-sided 8-mm extrameatal vestibular schwannoma and a left-sided almost purely extracranial glomus jugulare tumor of 18 mm. The pure-tone average values were 63 and 43 dB HL for the right and left ears, respectively. Speech audiometry showed a discrimination score of 76/88 (%). Caloric irrigation was performed and revealed a unilateral weakness of 81% towards the side of vestibular schwannoma. The patient was included in a watchful waiting regimen with annual MRI scans. CONCLUSION: Though vestibular schwannomas and glomus jugulare tumors are pathophysiologically different, they are similar in terms of symptomatology, growth pattern, diagnostic process, and therapeutic strategy. Based on this case report, it can be concluded that a vestibular evaluation demonstrates a unilateral vestibular weakness towards the side of the vestibular schwannoma, thereby facilitating clinical discrimination between the lesions.

Extended Retrolabyrinthine Approach: Results of Hearing Preservation Surgery Using a New System for Continuous Near Real-time Neuromonitoring in Patients With Growing Vestibular Schwannomas.

OBJECTIVE: To report hearing preservation results after retrolabyrinthine vestibular schwannoma surgery, using a new system for continuous near real-time monitoring of cochlear nerve function. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center, University Hospital. PATIENTS: Thirty-one consecutive patients with growing vestibular schwannomas and opting for hearing preservation surgery. INTERVENTIONS: Tumor removal by a modified, extended retrolabyrinthine approach, using a new system for continuous near real-time monitoring of cochlear nerve function. MAIN OUTCOME MEASURES: Pure-tone average and speech discrimination (SD) 1-year postoperative. Preservation of word recognition score class. Preservation of serviceable hearing (SD>50%). RESULTS: Any hearing was preserved in 83 and 69% had preserved word recognition score class or better. Serviceable hearing was preserved in 77%. SD was unchanged in 48%, improved in 21%, and poorer in 31%. Of 18 patients with potential for improvement (SD 90% or worse preoperatively), 33% improved (SD increase 10% or more). CONCLUSION: The hearing preservation rate is favorable using the modified, extended retrolabyrinthine approach and a new system for continuous near real-time monitoring of cochlear nerve function for removal of growing vestibular schwannomas, as 77% preserved serviceable hearing 1 year after surgery. Hearing improved after surgery in 33%. Using the new neuromonitoring system, serviceable hearing preservation rate improved from 53 to 77% at our center.

[Christmas article. Scientific spam].

INTRODUCTION: Predatory publishing has led to an increasing amount of scientific spam mails addressed to medical researchers. This study aimed at characterising this spam further. METHODS: Prospective study of spam received during a three-month-period. RESULTS: A total of 137 spam e-mails with scientific contents were received. The majority (88%) was automatically led to the spam filter. The mails represented various invitations from journals (77%), conferences (19%) and other (4%). Most of the mails used titles, had opening lines or flattery contents, and spelling, grammar or layout errors were common. CONCLUSION: Since spam filters are not completely accurate, screening is often necessary, however, responding to unsolicited predatory scientific spam should be avoided.

Facial nerve schwannomas presenting with vestibular dysfunction: a case series.

Facial nerve schwannomas (FS) can symptomatically mimic vestibular schwannomas (VS). In addition, FS can be difficult to distinguish from VS on magnetic resonance imaging (MRI). Although disequilibrium is not uncommon in patients with FS, no previous studies have investigated the vestibular function in such patients. Three cases of FS presented vestibular dysfunction as measured with caloric test, video head impulse test (VHIT), and vestibular evoked myogenic potentials (VEMPs). All patients in this study had a considerable affection of the vestibular function as assessed by the vestibular test panel. Audiovestibular evaluation of FS provides important information that may influence treatment strategy. As VS, FS should be evaluated with vestibular tests prior to intervention.

[Workup and treatment of vestibular schwannomas].

Vestibular schwannomas are benign tumours originating from the eighth cranial nerve. The incidence in Denmark is rising and is around 200 per million per year. Pure tone audiometry, discrimination score and tinnitus anamnesis determine, whether a diagnostic MRI is merited. Around one fourth of newly diagnosed patients receive surgery due to the size of the tumour, whereas the remaining three fourths go into a "wait-and-scan" regime. 30-40% of the patients in this regime experience growth and are offered either surgery or radiotherapy.

Contemporary Molecular Biology of Sporadic Vestibular Schwannomas: A Systematic Review and Clinical Implications.

In light of missing systematic reviews in the literature, the objective of this paper is to present the contemporary knowledge on the molecular biology of vestibular schwannomas (VS), based on a systematic literature search. In addition, current and prospected medical therapy based on molecular biology is addressed. A systematic literature search was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The systematic search was performed in the Pubmed and Embase databases. The following were the words searched: acoustic neuroma/vestibular schwannoma, molecular biology, gene, and microRNA. Specific inclusion and exclusion criteria were determined prior to search. The systematic search rendered 486 articles, ultimately yielding 69 included articles, whereas 35 were from relevant references. The occurrence of at least one mutation in the merlin gene was reported to range between 54% and 76%, whereas the loss of heterozygosity (LOH) corresponding to chromosome 22 occurs in 25% to 83% of sporadic VS. Global gene expression studies indicate that a number of genes other than merlin are at play. No high-level methylation of the merlin gene has been found. Several miRNAs are deregulated in tumor tissue, among others let-7d, miR-221, and miR-21. The acquired knowledge on molecular biology has led to several clinical implementations. Lack of the tumor suppressor merlin plays a principal role in the development of VS. Existing knowledge on the molecular biology has led to the first attempts of targeted medical treatment to prevent tumor growth. Future research is likely to introduce potential imaging markers with prognostic value and new targets for medical therapy.

Gene expression, signal transduction pathways and functional networks associated with growth of sporadic vestibular schwannomas.

The objective of this study was to determine global gene expression in relation to Vestibular schwannomas (VS) growth rate and to identify signal transduction pathways and functional molecular networks associated with growth. Repeated magnetic resonance imaging (MRI) prior to surgery determined tumor growth rate. Following tissue sampling during surgery, mRNA was extracted from 16 sporadic VS. Double stranded cDNA was synthesized from the mRNA and used as template for in vitro transcription reaction to synthesize biotin-labeled antisense cRNA, which was hybridized to Affymetrix HG-U133A arrays and analyzed by dChip software. Differential gene expression was defined as a 1.5-fold difference between fast and slow growing tumors (><0.5 ccm/year), employing a p-value <0.01. Deregulated transcripts were matched against established gene ontology. Ingenuity Pathway Analysis was used for identification of signal transduction pathways and functional molecular networks associated with tumor growth. In total 109 genes were deregulated in relation to tumor growth rate. Genes associated with apoptosis, growth and cell proliferation were deregulated. Gene ontology included regulation of the cell cycle, cell differentiation and proliferation, among other functions. Fourteen pathways were associated with tumor growth. Five functional molecular networks were generated. This first study on global gene expression in relation to vestibular schwannoma growth rate identified several genes, signal transduction pathways and functional networks associated with tumor progression. Specific genes involved in apoptosis, cell growth and proliferation were deregulated in fast growing tumors. Fourteen pathways were associated with tumor growth. Generated functional networks underlined the importance of the PI3K family, among others.