Salivary simulation with ascorbic acid enhances sonographic diagnosis of obstructive sialadenitis

Abstract

High-frequency ultrasound (US) is routinely used to evaluate various diseases of the salivary glands. Normally, the duct network of the submandibular and parotid glands is not visible during US assessment. In obstructive sialadenitis of the parotid and submandibular glands, localization of the obstacle is often difficult. In a case-control study, the sonographic visibility of the duct before and after stimulation with oral ascorbic acid (vitamin C) was compared with sialendoscopy as the gold standard. Twenty male and 23 female patients suffering from salivary gland diseases were included in this study and compared with 25 healthy volunteers. US examination of the parotid and submandibular glands was performed before and after oral ascorbic acid stimulation. Changes in visibility of the main excretory duct were recorded and US diagnoses were compared with results of sialendoscopy. In 7 of 25 controls, the main duct became partially visible after stimulation. In the group of 43 patients, the main duct was depicted before stimulation in 27 patients (63%). After ascorbic acid stimulation, the main duct became visible in 41 patients (95%). Grading the stimulated duct dilation by measuring diameters at different points revealed no correlation with the underlying type of pathology. Application of ascorbic acid prior to diagnostic US examination facilitates the sonographic evaluation of obstructive salivary gland diseases.