Beijing
China
IgG4-related disease; sialadenitis, salivary glands; ultrasonography, scoring system; US, ultrasonography; IgG4-RS, IgG4-related sialadenitis; non-IgG4-RS, non IgG4- related sialadenitis; PG, parotid gland; SMG, submandibular gland; SLG, sublingual gland; PG+SG