Salivary gland function evaluated by diffusion‐weighted MR imaging with gustatory stimulation: Preliminary results

AbstractPurpose:To evaluate the usefulness of diffusion‐weighted MR imaging using a transient gustatory stimulation method in patients with xerostomia.Materials and Methods:Ten consecutive patients complaining of xerostomia and 10 healthy volunteers were examined with a 1.5 Tesla (T) MR unit. All study subjects completed a questionnaire, and patients underwent salivary gland scintigraphy and Saxon test. T1‐, T2‐, and diffusion‐weighted MR images were obtained before stimulation. One minute after gustatory stimulation with lemon juice, diffusion‐weighted sequence was repeated 9 times. A radiologist evaluated signal intensities and apparent diffusion coefficients (ADCs) in parotid and submandibular glands. ADC increase rate (IR) and times to maximum ADC (Tmax) were assessed.Results:IRs showed a moderate positive correlation with washout rates by scintigraphy for parotid (r = 0.554, P < 0.05) and submandibular (r = 0.617, P < 0.01) glands. Furthermore, Tmax values of parotid and submandibular glands were significantly higher in patients (420 ± 226 and 357 ± 232 s, respectively) than in volunteers (181 ± 68 and 200 ± 75 s, respectively) (P < 0.01).Conclusion:Our preliminary results indicate that diffusion‐weighted MR imaging using a transient gustatory stimulation method is potentially useful for evaluating patients with xerostomia. J. Magn. Reson. Imaging 2011;.