**1. Introduction**

There have been many studies of clinical applications of magnetic resonance imaging (MRI) for evaluation, in addition to the evaluation of morphology, due to the higher quality of MRI

technology [1–8]. As for our study, the technique of "dynamic MR sialography" was named and introduced because of its clinical usefulness in visualizing the excretion of saliva from the parotid and submandibular glands, and in evaluating the diagnosis of morphology and functions for both glands and the outcomes of treatments for Sjögren's syndrome and xerostomia [1,9–12]. However, the visualization of the sublingual gland ducts is not considered even on MR imaging because it is difficult to visualize the very thin and short ducts, as seen in anatomy textbooks [13].

In our experience, the sublingual gland duct-like structures visualized and the possibility of visualizing the sublingual gland ducts by MR sialography needed to be elucidated.

In the present study, the sublingual gland ducts could be visualized. In addition, the clinical significance of the visualization and/or evaluation of the function of sublingual gland ducts was evaluated by clinical application of these techniques for some patients with sublingual gland diseases.
