Clinical audit of ultrasonography for detecting sialoliths in the submandibular gland in paediatric patients: A comparison to computed tomography and magnetic resonance imaging.

Objectives:To compare the performance of ultrasonography with magnetic resonance imaging (MRI) and computed tomography (CT) for detecting submandibular sialoliths. Methods:Thirteen patients with suspected submandibular sialoliths who underwent ultrasonography and CT or MRI were included. Sialoliths were diagnosed using CT (11 cases) or MRI (two cases). The submandibular duct was classified into distal and proximal ducts based on the point around the mylohyoid muscle. Sialoliths located in the proximal duct were difficult to differentiate from those located within the submandibular gland (SMG). Therefore, the location of the sialoliths was classified as follows: within the SMG/proximal duct and within the distal duct. The ultrasound results were compared with CT/MRI results. Results:Of the 13 patients included, two had sialoliths in both the SMG/proximal duct and the distal duct, three had sialoliths in the SMG/proximal duct, and five had sialoliths in the distal duct on CT or MRI. In this small cohort, all five sialoliths in the SMG/proximal duct were detected by ultrasoonography; however, of the seven cases with sialoliths located in the distal duct, only three could be detected by ultrasonography. Conclusions:The incidence of sialoliths in the distal duct was higher than that in the SMG/proximal duct. Ultrasonography showed a good performance compared with CT/MRI in the SMG/proximal duct but not in the distal duct.