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

Abstract

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.

Brazilian Society of Otology task force – Vestibular Schwannoma ‒ evaluation and treatment

“…It should be noted that the ABR test is less sensitive and specific than MRI for detecting tumors smaller than 1 cm. 58 In the study by Urben et al, 61 179 out of 325 participants underwent ABR testing and only 15 (8.3%) of them had abnormal results. MRI and ABR studies over the last 10–15 years have repeatedly confirmed these results and demonstrated that ABR tests miss 30%–50% of small tumors.…”

“…VSs can often present with normal Otoacoustic Emissions (OAEs) and cochlear feedback and abnormal Auditory Brainstem Response (ABR), mimicking a form of auditory neuropathy. 58 ABR was used as a preliminary diagnostic method to select patients at high risk for VS prior to MRI examination. 58 , 59 The ABR using wave I–V latency differences was an important component of the clinical test battery for VS.…”

“… 58 ABR was used as a preliminary diagnostic method to select patients at high risk for VS prior to MRI examination. 58 , 59 The ABR using wave I–V latency differences was an important component of the clinical test battery for VS. Early studies claimed that the detection rates ranged from 95% to 98%, but the detected tumors were typically large.…”

“…The combination of 2 ABR measures leading to interaural wave V delay and interpeak wave I to wave V delay detected medium and large tumors very well but often missed small tumors (<1 cm). 58 …”

“…MRI and ABR studies over the last 10–15 years have repeatedly confirmed these results and demonstrated that ABR tests miss 30%–50% of small tumors. 58 …”