Cost considerations for vestibular schwannoma screening and imaging: a systematic review

Vestibular schwannomas (VS) account for approximately 8% of all intracranial neoplasms. Importantly, the cost of the diagnostic workup for VS, including the screening modalities most commonly used, has not been thoroughly investigated. Our aim is to conduct a systematic review of the published literature on costs associated with VS screening. A systematic review of the literature for cost of VS treatment was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The terms "vestibular schwannoma," "acoustic neuroma," and "cost" were queried using the PubMed and Embase databases. Studies from all countries were considered. Cost was then corrected for inflation using the US Bureau of Labor Statistics Inflation Calculator, correcting to April 2022. The search resulted in an initial review of 483 articles, of which 12 articles were included in the final analysis. Screening criteria were used for non-neurofibromatosis type I and II patients who complained of asymmetric hearing loss, tinnitus, or vertigo. Patients included in the studies ranged from 72 to 1249. The currency and inflation-adjusted mean cost was $418.40 (range, $21.81 to $487.03, n = 5) for auditory brainstem reflex and $1433.87 (range, $511.64 to $1762.15, n = 3) for non-contrasted computed tomography. A contrasted magnetic resonance imaging (MRI) scan was found to have a median cost of $913.27 (range, $172.25-$2733.99; n = 8) whereas a non-contrasted MRI was found to have a median cost of $478.62 (range, $116.61-$3256.38, n = 4). In terms of cost reporting, of the 12 articles, 1 (8.3%) of them separated out the cost elements, and 10 (83%) of them used local prices, which include institutional costs and/or average costs of multiple institutions. Our findings describe the limited data on published costs for screening and imaging of VS. The paucity of data and significant variability of costs between studies indicates that this endpoint is relatively unexplored, and the cost of screening is poorly understood.

Incidental findings on magnetic resonance imaging of the internal auditory meatus performed to investigate audiovestibular symptoms

OBJECTIVE

To determine the frequency of incidental findings found on magnetic resonance imaging scans of the internal auditory meatus performed to investigate audiovestibular symptoms, and to determine how to best manage these when found.

METHOD

A retrospective review was conducted of internal auditory meatus magnetic resonance imaging scans during a three-month period in the radiology department at a UK district general hospital.

RESULTS

A total of 109 scans were reviewed. Of these, 92.7 per cent showed no retrocochlear pathology, 0.9 per cent showed vestibular schwannoma, 6.4 per cent revealed vascular loops, and 2.8 per cent showed incidental findings that warranted further action and investigation. Of the scans, 40.4 per cent showed other incidental pathologies such as age-related ischaemic changes, and sinus disease that required no further intervention. Of the magnetic resonance imaging scans reviewed, 49.5 per cent were entirely normal.

CONCLUSION

Almost half of the scans investigating audiovestibular symptoms showed incidental findings. Otolaryngologists should have an understanding of the significance of the most commonly encountered incidental findings, and should counsel patients appropriately and refer them onward when necessary.

Cost-Effective Initial Screening for Vestibular Schwannoma: Auditory Brainstem Response or Magnetic Resonance Imaging?

OBJECTIVE: Our goal was to determine the cost-effectiveness of including auditory brainstem response (ABR) testing in a screening protocol for the diagnosis of vestibular schwannoma (VS) in patients with asymmetric auditory symptoms at the Christian Medical College and Hospital, Vellore, India, where, commonly, patients with VS have tumors greater than 2 cm at the time of diagnosis.

METHODS: Ninety patients with asymmetric audiovestibular symptoms were investigated prospectively with both ABR and gadolinum-enhanced magnetic resonance imaging (GdMRI).

RESULTS: Of these 90 patients, 6 were diagnosed with VS on GdMRI. On ABR testing, 4 patients with VS had retrocochlear pathology and 2 with profound sensorineural hearing loss had no responses. ABR was found to have a sensitivity of 100% and specificity of 61.9%. A protocol involving screening of all patients with asymmetric audiovestibular symptoms using ABR and only subjecting those patients with no responses or retrocochlear pathology to GdMRI would effect a savings of $1200 for every patient detected to have a VS.

CONCLUSIONS: In our hospital setting, including ABR as the preliminary screen for patients with asymmetric audiovestibular symptoms is a cost-effective strategy.

Screening for cerebellopontine angle tumours: conventional MRI vs T2 fast spin echo MRI

BACKGROUND

Unilateral audiovestibular symptoms are commonly seen in clinical practice and are rarely caused by retrocochlear pathology. However, clinicians are often required to rule out potentially serious causes of these unilateral symptoms. Gadolinium enhanced magnetic resonance imaging (GdMRI) is the most accurate test for detecting small cerebellopontine angle lesions and also screens the adjacent CNS structures. Its main disadvantage is the cost of the procedure.

METHODS

We studied 100 consecutive patients with both GdMRI and a newer MRI screening study utilizing unenhanced T2-weighted fast spin echo (fse) MRI. Acquired images were randomly assessed by a panel of three neuro-radiologists.

RESULTS

We found that the screening (fse) MRI was as sensitive and specific when detecting cerebellopontine angle tumors.

CONCLUSIONS

We conclude that T2-weighted fse MRI is a safe and cost-effective alternative to GdMRI and offers better diagnostic utility when compared to auditory brain stem response (ABR) and CT scans.