Assessing the diagnostic and therapeutic value of submandibular gland elastography in patients with immunoglobulin G4-related sialadenitis.

Objectives: : To investigate the utility of shear wave elastography values (SWE) in differentiating IgG4-related submandibular sialadenitis (IgG4-RSS) from healthy individuals and in monitoring the response to glucocorticoid treatment.

Methods: : Patients with IgG4-RSS who underwent ultrasound between 2017 and 2023 were included. Gland size, border, internal echo pattern, vascularity, and SWE were measured. These parameters were compared with those of the healthy controls, and before and after treatment.

Results: Thirty-one glands from 16 patients were analysed. All glands had a nodular shape; the nodular hypoechoic was the most prevalent pattern, followed by the diffuse hypoechoic; the reticular was the least common. Most glands had rich vascularity, whereas two glands had minimal vascularity. The depth (mean 18 mm) and SWE (mean 3.57 m/s) were significantly higher in IgG-RSS (P=0.003 and <0.001, respectively) than in the healthy controlsNine glands from five patients were enrolled to evaluate the treatment response. After treatment, the margins became smoother and all glands showed a reduction in size, hypoechoic area, and vascularity. The mean SWE decreased from 3.56 m/s to 2.50 m/s with a significant difference between pre- and post-treatment (P= <0.001).

Conclusions: The SWE is useful for diagnosing IgG4-RSS and assessing the effectiveness of treatment.