Quantitative Assessment of Vascularization and Stiffness in Salivary Glands During Pregnancy Using Superb...

The purpose of this research was to quantitatively evaluate the vascular supply and tissue stiffness of the salivary glands-namely, the submandibular and parotid glands-in pregnant individuals throughout the three trimesters, employing superb microvascular imaging (SMI) and shear wave elastography (SWE).

A longitudinal prospective study was executed involving 35 healthy pregnant women. Salivary gland ultrasonography was conducted during each trimester. The vascularization index (VI) was quantified using the two-dimensional SMI VI (2DcSMIVI) mode by manually delineating the glandular parenchyma. Glandular elasticity was measured through SWE in kilopascals (kPa) and meters per second (m/s). Statistical evaluations incorporated repeated measures ANOVA and the Friedman test (p < 0.05).

Submandibular gland stiffness showed significant trimester-based variations, with kPa values peaking in the second trimester and declining in the third (F(2,68) = 5.31, p < 0.05, η² = 0.13). Likewise, m/s values were elevated in the second trimester relative to the third (X² = 7.79, p < 0.05). In contrast, the stiffness and VI values of the parotid gland exhibited consistency across trimesters (p > 0.05).

The dynamic shifts in submandibular gland stiffness, highlighted by a rise in the second trimester followed by a decrease in the third, most likely signify the hormonal and hemodynamic adaptations that come with pregnancy. These findings underscore the importance of monitoring salivary gland function in pregnant women and pave the way for future investigations into the diagnostic and prognostic implications of these changes. To the best of our knowledge, this represents the inaugural study demonstrating normative stiffness and vascularity parameters of salivary glands across each trimester of pregnancy.