Multimodal Elastography of the Main Salivary Glands-A Narrative Review

Abstract

Elastography has emerged as a valuable imaging technique that evaluates tissue stiffness and offers complementary insights into conventional ultrasonography. The aim of this article is to review the utility of elastography in assessing salivary gland pathologies. The review categorizes findings by pathology and the physical principles underlying each elastographic modality. Key modalities discussed include strain elastography, shear wave elastography, and novel hybrid techniques, such as viscoelastography, highlighting their strengths, limitations, and clinical applications in salivary gland imaging.

Keywords: parotid gland; salivary glands pathology; shear wave elastography; strain elastography; submandibular gland; viscoelastography.

Figure 1

Classification of the elastography techniques; adapted after [2].

Figure 2

2D-SWE examination of the parotid gland (A) and submandibular gland (B) healthy subject.

Figure 3

2D-SWE examination of the parotid gland in a patient with pSS without lymphomatous proliferation (A) and a patient with pSS and associated MALT lymphoma that demonstrates higher stiffness values (B).

Figure 4

Illustration of SE patterns in parotid gland tumors. (A). Pleomorphic adenoma with SE score 1 (almost completely green). (B). Adenoid cystic carcinoma with SE score 3 (mostly blue with some green areas).

Figure 5

Viscosity assessment of the main salivary glands ((A). submandibular gland; (B). parotid gland) in a healthy subject using the Vi.PLUS module available on the Supersonic Imagine Aixplorer ultrasound device. A color-coded map is displayed in the Vi.PLUS box: high viscosity is represented by the colors white–yellow, while low viscosity is represented in red. Numeric viscosity results (the mean, median, and standard deviation values expressed in Pa.s) are displayed on the right side of the image.