The Relation Between Tinnitus and a Neurovascular Conflict of the Cochleovestibular Nerve on Magnetic Resonance Imaging.

INTRODUCTION: Magnetic resonance (MR) imaging is often used in diagnostic evaluation of tinnitus patients. Incidental findings like a neurovascular conflict (NVC) in the cerebellopontine angle are often found; however, the diagnostic value of this finding remains unclear. The aim of this study is to investigate whether the type or degree of compression of the vestibulocochlear nerve is of diagnostic value in patients with a NVC. METHODS: A retrospective study was performed in 111 tinnitus patients with available MR imaging between 2013 and 2015. Clinical and audiometric variables were gathered and MR imaging was reevaluated by two neuroradiologists. NVCs were analyzed using a grading system based on previous research by Sirikci et al. RESULTS:: In total, 220 ears were available for assessment. In patients with unilateral tinnitus a loop compression and an indentation of the cochleovestibular nerve were more frequent than in patients with bilateral tinnitus. However, there was no significant difference in distribution of the type of compression between tinnitus and nontinnitus ears. Patient with unilateral tinnitus had a significantly higher degree of hearing loss in the symptomatic ear, compared with the asymptomatic ear and with the bilateral tinnitus group. Also, it was found that the degree of hearing loss did not differ between the various types of compression. CONCLUSION: This study did not find a diagnostic value of specific types of compression in patients with a NVC. Although the distribution of NVC classification was different in patients with unilateral and bilateral tinnitus, there was no definite relation between the type of NVC and the presence of ipsilateral tinnitus. Also, the degree of hearing loss was not related to specific types of NVC.

An auditory brainstem implant for treatment of unilateral tinnitus: protocol for an interventional pilot study.

INTRODUCTION: Tinnitus may have a very severe impact on the quality of life. Unfortunately, for many patients, a satisfactory treatment modality is lacking. The auditory brainstem implant (ABI) was originally indicated for hearing restoration in patients with non-functional cochlear nerves, for example, in neurofibromatosis type II. In analogy to a cochlear implant (CI), it has been demonstrated that an ABI may reduce tinnitus as a beneficial side effect. For tinnitus treatment, an ABI may have an advantage over a CI, as cochlear implantation can harm inner ear structures due to its invasiveness, while an ABI is presumed to not damage anatomical structures. This is the first study to implant an ABI to investigate its effect on intractable tinnitus. METHODS AND ANALYSIS: In this pilot study, 10 adults having incapacitating unilateral intractable tinnitus and ipsilateral severe hearing loss will have an ABI implanted. The ABI is switched on 6 weeks after implantation, followed by several fitting sessions aimed at finding an optimal stimulation strategy. The primary outcome will be the change in Tinnitus Functioning Index. Secondary outcomes will be tinnitus burden and quality of life (using Tinnitus Handicap Inventory and Hospital Anxiety and Depression Scale questionnaires), tinnitus characteristics (using Visual Analogue Scale, a tinnitus analysis), safety, audiometric and vestibular function. The end point is set at 1 year after implantation. Follow-up will continue until 5 years after implantation. ETHICS AND DISSEMINATION: The protocol was reviewed and approved by the Institutional Review Board of the University Medical Centre Groningen, The Netherlands (METc 2015/479). The trial is registered at www.clinicialtrials.gov and will be updated if amendments are made. Results of this study will be disseminated in peer-reviewed journals and at scientific conferences. TRIAL REGISTRATION NUMBER: NCT02630589. TRIAL STATUS: Inclusion of first patient in November 2017. Data collection is in progress. Trial is open for further inclusion. The trial ends at 5 years after inclusion of the last patient.

Development of the Endoscopic Endonasal Sinus and Skull Base Surgery Questionnaire.

BACKGROUND: The patients' perspective of health outcomes has become important input for assessing treatment effects. However, existing endoscopic endonasal surgery (EES) instruments are not fully aligned with the concept of health-related quality of life (HRQoL). A prospective cohort study was therefore conducted to develop a suitable quality-of-life tool to assess nasal morbidity after EES: the Endoscopic Endonasal Sinus and Skull Base Surgery Questionnaire (EES-Q). METHODS: The study included 300 patients: 207 with sinus pathology and 93 with anterior skull base pathology. The EES-Q was administered prior to surgery and postoperatively (2 weeks, 3 months, and 1 year). Psychometric instrument properties were tested and relevant health domains were formulated. Seventy-two items were generated by the conventional psychometric approach. An exploratory factor analysis was used to test construct validity. The optimal number of factors to retain was determined by using the eigenvalues-greater-than-1 rule and scree plot. Orthogonal varimax rotation was used to enhance interpretability. Internal consistency was assessed using the Cronbach α. RESULTS: The factor analysis yielded a 3-factor solution, representing physical, psychological, and social functioning. The final version of the instrument consisted of 30 items with a high internal consistency (>0.80) for all 3 HRQoL domains. CONCLUSIONS: The EES-Q is a comprehensive, multidimensional, disease-specific instrument. A distinguishing characteristic is that, apart from the physical and psychological domains, the EES-Q also encompasses a social domain. Understanding different HRQoL aspects in patients undergoing EES may help caregivers restore, improve, or preserve the patient's health through individualized care, which depends on identifying their specific needs.

Cluster Analysis to Identify Possible Subgroups in Tinnitus Patients.

INTRODUCTION: In tinnitus treatment, there is a tendency to shift from a "one size fits all" to a more individual, patient-tailored approach. Insight in the heterogeneity of the tinnitus spectrum might improve the management of tinnitus patients in terms of choice of treatment and identification of patients with severe mental distress. The goal of this study was to identify subgroups in a large group of tinnitus patients. METHODS: Data were collected from patients with severe tinnitus complaints visiting our tertiary referral tinnitus care group at the University Medical Center Groningen. Patient-reported and physician-reported variables were collected during their visit to our clinic. Cluster analyses were used to characterize subgroups. For the selection of the right variables to enter in the cluster analysis, two approaches were used: (1) variable reduction with principle component analysis and (2) variable selection based on expert opinion. RESULTS: Various variables of 1,783 tinnitus patients were included in the analyses. Cluster analysis (1) included 976 patients and resulted in a four-cluster solution. The effect of external influences was the most discriminative between the groups, or clusters, of patients. The "silhouette measure" of the cluster outcome was low (0.2), indicating a "no substantial" cluster structure. Cluster analysis (2) included 761 patients and resulted in a three-cluster solution, comparable to the first analysis. Again, a "no substantial" cluster structure was found (0.2). CONCLUSION: Two cluster analyses on a large database of tinnitus patients revealed that clusters of patients are mostly formed by a different response of external influences on their disease. However, both cluster outcomes based on this dataset showed a poor stability, suggesting that our tinnitus population comprises a continuum rather than a number of clearly defined subgroups.

Microvascular decompression of the cochleovestibular nerve for treatment of tinnitus and vertigo: a systematic review and meta-analysis of individual patient data.

OBJECTIVE Microvascular decompression (MVD) is regarded as a valid treatment modality in neurovascular conflicts (NVCs) causing, for example, trigeminal neuralgia and hemifacial spasms. An NVC of the cochleovestibular nerve might cause tinnitus and/or vertigo; however, general acceptance of MVD for this indication is lacking. The aim of this study was to investigate the effectiveness, safety, and prognostic factors for success of MVD of the cochleovestibular nerve. METHODS A systematic review and meta-analysis of individual patient data (IPD) were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Individual Patient Data (PRISMA-IPD) guidelines. By a comprehensive search (conducted in January 2016) in MEDLINE, EMBASE, and Google Scholar, eligible studies were identified. The collected outcome was a global measurement of improvement of 1) tinnitus, 2) vertigo, and 3) tinnitus combined with vertigo. For the meta-analysis, IPD were collected from the papers and/or from the authors. IPD were analyzed with logistic regression analysis while accounting for study clustering. RESULTS Thirty-five studies (572 patients) were included. The level of evidence provided by these studies was low. In 28% of patients with tinnitus and 32% of patients with vertigo, complete relief following MVD was reported. Patients with both tinnitus and vertigo had complete relief in 62% of cases. In 11% of patients, ≥ 1 complications were reported. Meta-analysis of IPD (165 patients) demonstrated that patients with both tinnitus and vertigo had a higher chance of success (OR 3.8, 95% CI 1.45-10.10) than patients with tinnitus alone. No other variables were significantly related to success. CONCLUSIONS Due to low success rates, MVD cannot be considered as a standard treatment method for tinnitus or vertigo. Moreover, a substantial complication rate was found. However, patients with combined symptoms had a higher chance of success. When combined symptoms occur, it is more likely that an NVC is the underlying pathology and MVD might be appropriate. Due to the low level of evidence in the included studies, this conclusion must be taken with caution. Further validation is necessary to evaluate whether patients with combined symptoms are indeed better candidates for MVD.

Effect of Direct Stimulation of the Cochleovestibular Nerve on Tinnitus: A Long-Term Follow-Up Study.

OBJECTIVE: Tinnitus is a common entity that may lead to severe impairment in quality of life. An adequate treatment modality for severe tinnitus is currently lacking. Neurostimulation of the auditory tract may serve as a promising adjunct in tinnitus treatment. The aim is to investigate the effect of direct stimulation on the cochleovestibular nerve for intractable tinnitus. METHODS: This study was conducted at the University Medical Center Groningen, The Netherlands. We studied 10 patients with severe, unilateral, intractable tinnitus, who were implanted with a cuff electrode around the cochleovestibular nerve between 2001 and 2013. All patients had preoperative ipsilateral hearing loss. Tinnitus Handicap Inventory (THI) scores and audiometric values were collected. Treatment success was determined based on the self-assessment of satisfactory usage by each patient. RESULTS: The mean preoperative tinnitus duration was 8.0 ± 5.9 years. The preoperative THI score was 71 ± 18 points. During mean follow-up of 49 months, the mean THI reduction was 24 ± 26 points (P = 0.02). Treatment was regarded successful in 6 patients (60%). In these patients, tinnitus did not disappear, but transformed into a more bearable sound. In 4 patients, transient complications occurred, and 1 patient experienced permanent vertigo postoperatively. Furthermore, hearing deterioration was a result of implantation in 86% of the patients. CONCLUSIONS: Direct neurostimulation resulted in treatment success in a small majority of the patients, with a significant decrease in THI score. However, because of a high risk of additional hearing damage, this technique seems not viable for patients with moderate hearing loss.