To assess abnormalities in blood flow to the submandibular glands of patients with Sjögren's syndrome (SS).
Doppler waveform analysis was performed on the facial artery to assess blood inflow to the submandibular gland of 21 patients with primary SS and 69 healthy subjects. Blood flows were compared before and after secretory stimulation with lemon extracts.
The facial artery of healthy subjects in the resting state exhibited a biphasic waveform with a high systolic peak and a prominent second peak of compliance followed by a low diastolic flow. In contrast, the waveform of patients with SS was more uniform compared with the healthy subjects, substantiated by decreased resistive and pulsatility indices, suggesting a hyperemic state of the downstream vascular bed. After stimulation of salivary secretion, the facial artery of healthy subjects responded by decreasing resistive and pulsatility indices, waveform changes indicative of increased blood inflow to the submandibular gland. In contrast, the facial artery of patients with SS responded insufficiently to the stimulation, with the magnitude of changes in the resistive and pulsatility indices being significantly lower than those of the controls. Doppler waveform abnormalities were correlated with the severity of gland damage, supporting a close connection between abnormal blood inflow to the salivary gland and impaired secretory function in SS.
Our findings suggest that blood inflow responses to secretory stimulation may be defective in the salivary glands of patients with SS.