Magnetic resonance imaging in gustatory disorders: diagnostic usefulness with a cost analysis.

OBJECTIVE: Beyond patient history, clinical examination and psychophysical gustatory testing, no standardized guidelines exist for the diagnosis of unclear taste disorders, especially regarding imaging. We therefore aimed to investigate the frequency of use of magnetic resonance imaging (MRI), the findings, and the cost and benefits in a large cohort of patients with taste disorders presenting at a tertiary referral centre over a period of 10 years. METHODOLOGY: We retrospectively reviewed clinical records of all patients with gustatory disorders presenting at our tertiary smell and taste clinic between 2010 and 2019 who received an MRI. A board-certified neuroradiologist, specialized in head and neck imaging, reviewed all MRIs. MRI findings were classified according to their relevance to the taste disorder. A cost-benefit analysis was performed. RESULTS: Of the 125 patients with taste complaints, 70 underwent MRI. Imaging data were retrievable for 65 patients, representing 52% of the total cohort. Pathological findings were observed in 54 patients; 46 had incidentalomas not related to the initial complaint. Findings potentially related to the gustatory complaint (treatable in 6 cases, not treatable in 2 cases) were seen in only 8 MR scans. The imaging findings matched the clinical findings in only 4 cases, and these were therefore classified as clearly related to the complaint. The total cost of all the MRIs performed was 55,034.89 CHF. The estimated costs per finding attributable to a taste disorder were 13,758.72 CHF. CONCLUSIONS: In this selected cohort of patients with isolated taste disorders, MRI rarely revealed findings clearly attributable to the complaint. While incidentalomas were frequent, clinically relevant abnormalities were uncommon. These results suggest that MRI should be reserved for select cases, and its routine use critically evaluated. Further prospective studies are needed to better define when MRI is warranted in the diagnosis of unclear isolated taste disorders.