Magnetic Resonance Sialography and Salivary Gland Scintigraphy of Parotid Glands in Sjögren's Syndrome

Objective: To assess the correlation between conventional magnetic resonance (MR) imaging and MR sialography of parotid glands with salivary gland scintigraphy in patients with Sjögren's syndrome. Methods: A retrospective study was conducted on eight patients with Sjögren's syndrome who underwent MR imaging and salivary gland scintigraphy. Conventional MR imaging techniques, such as T1-weighted images (T1WI), T2-weighted images (T2WI), and short TI inversion recovery images (STIR) were used for changes of fat signal in the parotid gland, while the MR sialography were used for ducts dilation of the parotid gland. Regarding scintigraphy, time-activity curves of each parotid gland were analysed. The salivary gland excretion fraction was defined as A (before stimulation test (counts/20 s)) and B (after stimulation test (counts/20 s)). Results: Regarding characteristic appearances of fat signal, the A/B of parotid gland with homogeneous intensity distribution (3.51 ± 0.75) was higher than that with heterogeneous intensity distribution (1.56 ± 0.66, P = 0.001). Regarding MR sialographic stages, the A/B of parotid gland with stage 0 (3.51 ± 0.75) was higher than that with stage 1 (2.03 ± 0.86, P = 0.009) and with stage 2 (1.26 ± 0.25, P = 0.000). Conclusion: The results suggest that MR sialography of the parotid glands is a useful noninvasive tool for evaluating the decrease of salivary gland excretion in patients with Sjögren's syndrome. Keywords: magnetic resonance imaging, parotid gland, sialography, Sjögren's syndrome