Auditory brainstem response prior to MRI compared to standalone MRI in the detection of vestibular schwannoma: A modelling study.

OBJECTIVES: To determine the cost-effectiveness of auditory brainstem response prior to MRI (ABR-MRI) compared to standalone MRI to diagnose vestibular schwannoma. DESIGN: A state transition model was developed to simulate costs and effects (quality-adjusted life years [QALY]) for both diagnostic strategies for patients suspected of a vestibular schwannoma. Model input was derived from literature, hospital databases and expert opinions. Scenario and sensitivity analyses addressed model uncertainty. RESULTS: Over a lifetime horizon, ABR-MRI resulted in a limited cost-saving of €68 or €98 per patient (dependent on MRI sequence) and a health loss of 0.005 QALYs over standalone MRI. ABR-MRI, however, did miss patients with other important pathology (2% of the population) that would have been detected when using standalone MRI. In total, €14 203 or €19 550 could be saved per lost QALY if ABR-MRI was used instead of standalone MRI. The results were sensitive to the detection rate of vestibular schwannoma and health-related quality of life of missed patients. CONCLUSION: The cost-saving with ABR-MRI does not seem to outweigh the number of missed patients with VS and other important pathologies that would have been detected when using standalone MRI.

What determines quality of life in patients with vestibular schwannoma?

OBJECTIVES: Patients with a vestibular schwannoma (VS) experience a reduced quality of life (QoL). The main objective of this study was to determine the strongest predictors reducing physical and mental QoL from the disease-specific Penn Acoustic Neuroma Quality of Life (PANQOL) questionnaire in patients with VS. DESIGN: Observational study. SETTING: Radboudumc Skull Base Centre, Nijmegen. PARTICIPANTS: Patients newly diagnosed with VS between 2014 and 2017 managed with either observation, stereotactic radiosurgery or microsurgery. MAIN OUTCOME MEASURES: Quality of life was assessed using the disease-specific PANQOL and general Short-Form (36) Health Survey (SF-36). Multiple linear regression models with PANQOL domains as predictors were used to determine the strongest predictors for SF-36 QoL physical and mental health scores. Standardised beta coefficients (ß) were used for ranking. RESULTS: A total of 174 patients (50% females, mean age 58.9 years) returned the questionnaires, providing a 69% response rate. Fifteen patients (9%) were treated with microsurgery, 29 (17%) with stereotactic radiosurgery and 130 patients (75%) were observed in a wait and scan strategy. A lack of energy (ß = .28; P ≤ .001), lower general health (ß = .22; P ≤ .001), headache (ß = .16; P ≤ .001), anxiety (ß = .15; P ≤ .001) and balance problems (ß = .10; P ≤ .001) are the strongest predictors affecting physical health, while mental health is most affected by anxiety (ß = .37; P ≤ .001), a lack of energy (ß = .34; P ≤ .001), facial nerve dysfunction (ß = .07; P ≤ .001), balance problems (ß = .04; P ≤ .001) and headaches (ß = .04; P ≤ .001). CONCLUSION: A lack of energy, anxiety, headache and balance problems are the strongest predictors of both SF-36 physical and mental QoL in patients with VS. More awareness and supportive care regarding energy, anxiety, headache and balance in informing, evaluating and treating patients with VS could improve QoL.

Development of a model to predict vestibular schwannoma growth: An opportunity to introduce new wait and scan strategies.

OBJECTIVES: To develop a prediction model to predict vestibular schwannoma (VS) growth for patients in a wait and scan (W&S) strategy. DESIGN: Retrospective cohort study. SETTING: Tertiary hospital (Radboud university medical center, Nijmegen, the Netherlands). PARTICIPANTS: Patients with unilateral VS, entering a W&S strategy and at least one follow-up MRI available. Data on demographics, symptoms, audiometry and MRI characteristics at time of diagnosis were collected from medical records. MAIN OUTCOME MEASURES: Following multiple imputation, a multivariable Cox regression model was used to select variables, using VS growth (≥2 mm) as outcome. Decision curve analyses (DCA) were performed to compare the model to the current strategy. RESULTS: Of 1217 analysed VS patients, 653 (53.7%) showed growth during follow-up. Balance complaints (HR 1.57 (95% CI: 1.31-1.88)) and tinnitus complaints in the affected ear (HR 1.36 (95% CI: 1.15-1.61)), Koos grade (Koos 1 is reference, Koos 2 HR 1.03 (95% CI: 0.80-1.31), Koos 3 HR 1.55 (95% CI: 1.16-2.06), Koos 4 HR 2.18 (95% CI: 1.60-2.96)), time since onset of symptoms (IQR HR 0.83 (95% CI: 0.77-0.88) and intrameatal diameter on MRI (IQR HR 1.67 (95% CI: 1.42-1.96)) were selected as significant predictors. The model's discrimination (Harrell's C) was 0.69 (95% CI: 0.67-0.71), and calibration was good. DCA showed that the model has a higher net benefit than the current strategy for probabilities of VS growth of >12%, 15% and 21% for the first consecutive 3 years, respectively. CONCLUSIONS: Patients with balance and tinnitus complaints, a higher Koos grade, short duration of symptoms and a larger intrameatal diameter at time of diagnosis have a higher probability of future VS growth. After external validation, this model may be used to inform patients about their prognosis, individualise the W&S strategy and improve (cost-)effectiveness.

In search of the most cost-effective monitoring strategy for vestibular schwannoma: A decision analytical modelling study.

OBJECTIVES: To assess the cost-effectiveness of frequently used monitoring strategies for vestibular schwannoma (VS). DESIGN: A state transition model was developed to compare six monitoring strategies for patients with VS: lifelong annual monitoring; annual monitoring for the first 10 years after diagnosis; scanning at 1-5, 7, 9, 12, 15 years after diagnosis and subsequently every 5 years; a personalised monitoring strategy for small and large tumours; scanning at 1, 2 and 5 years after diagnosis and no monitoring. Input data were derived from literature and expert opinion. Quality-adjusted life years (QALYs) and healthcare costs of each strategy were modelled over lifetime. Net monetary benefits (NMBs) were calculated to determine which strategy provided most value for money. Sensitivity analyses were performed to address uncertainty. RESULTS: Omitting monitoring is least effective with 18.23 (95% CI 16.84-19.37) QALYs per patient, and lifelong annual monitoring is most effective with 18.66 (95% CI 17.42-19.65) QALYs. Corresponding costs were €6526 (95% CI 5923-7058) and €9429 (95% CI 9197-9643) per patient, respectively. Lifelong annual monitoring provided the best value with a NMB of €363 765 (339 040-383 697), but the overall probability of being most cost-effective compared to the other strategies was still only 23%. Sensitivity analysis shows that there is large uncertainty in the effectiveness of all strategies, with largely overlapping 95% confidence intervals for all strategies. CONCLUSIONS: Due to the largely overlapping 95% confidence intervals of all monitoring strategies for VS, it is unclear which monitoring strategy provides most value for money at this moment.

Limited evidence for the effect of sodium fluoride on deterioration of hearing loss in patients with otosclerosis: a systematic review of the literature.

OBJECTIVE: To determine the protective effect of sodium fluoride on the deterioration of hearing loss in adult patients with otosclerosis. DATA SOURCES: PubMed, Embase, the Cochrane Library, and CINAHL. STUDY SELECTION: A systematic literature search was conducted. Studies reporting original study data on the deterioration of hearing loss in otosclerosis patients treated with sodium fluoride were included. DATA EXTRACTION: Directness of evidence (DoE) and risk of bias (RoB), using the Cochrane Collaboration's tool for assessing risk of bias, of the selected articles were assessed. Studies with low DoE, high RoB, or both were excluded. Absolute risks, mean deterioration of hearing in decibels, risk differences, and their 95% confidence intervals were extracted from the included studies. DATA SYNTHESIS: Our search yielded 168 original titles, of which, 2 placebo-controlled studies were eligible for data extraction. The results of these 2 studies were conflicting. One of the included studies, with high DoE and moderate RoB, reported an absolute risk reduction for deterioration of hearing loss of 18% [95% CI 17; 19] when treating with sodium fluoride. The other included study, with high DoE and moderate RoB, reported no clinically significant difference in mean deterioration of bone-conduction, air-conduction, or air-bone gap between the sodium fluoride group and the placebo group. CONCLUSION: There is weak evidence from one study with significant limitations that deterioration of hearing loss in otosclerosis patients receiving sodium fluoride treatment is less than in patients treated with a placebo.

Pure-tone audiometry in otosclerosis: insufficient evidence for the diagnostic value of the Carhart notch.

OBJECTIVE: To evaluate whether the Carhart notch on pure-tone audiometry is reliable as a diagnostic test for predicting otosclerosis in patients with conductive hearing loss. Data Sources PubMed, Embase, the Cochrane Library, CINAHL, and Scopus. METHODS: A systematic search was conducted. Studies reporting original study data were included. After assessment of directness of evidence and risk of bias of the selected articles, the prevalences and the positive and negative predictive values were extracted. RESULTS: A total of 1402 unique studies was retrieved. Three of these satisfied the eligibility criteria. One study provided direct evidence, while all studies carried moderate to high risk of bias. One study with moderate directness of evidence and high risk of bias was not further analyzed. In a study with a high directness of evidence, a high risk of bias, and a low prevalence of otosclerosis (8%) in patients with conductive hearing loss, the presence of a Carhart notch at 2000 Hz increased the risk of otosclerosis with 33%. In a second study with moderate directness of evidence, moderate risk of bias, and a high prevalence of otosclerosis (72%) in patients with a surgically confirmed congenital ossicular anomaly or otosclerosis, the presence of a Carhart notch at 2000 Hz increased the risk of otosclerosis with 2%. CONCLUSION AND RECOMMENDATION: Although there is insufficient high-quality evidence regarding the diagnostic value of the Carhart notch, it seems it is a useful hint for the presence of otosclerosis, but it cannot be used to confirm a diagnosis of otosclerosis.