Purpose: This study aimed to determine the efficacy of acoustic radiation force impulse (ARFI) imaging for the functional assessment of salivary glands by comparing ARFI with salivary gland scintigraphy.
Materials and methods: We prospectively evaluated 60 parotid (P) glands and 60 submandibular (SM) glands of 30 patients using salivary gland scintigraphy and ARFI elastography. The average pixel uptake and the excretion fraction (EF) in the P and SM glands were determined scintigraphically. The degree of stiffness in the P and SM glands at prelemon and postlemon stimulation periods were measured elastographically with ARFI. Changes in the degree of stiffness of the P and SM glands were also calculated with lemon stimulation. The scintigraphic and elastographic parameters were then compared statistically.
Results: We found a moderate linear correlation between the excretion function and the changes in the degree of stiffness of the P and SM glands induced by lemon stimulation (P<0.001, r=0.661; P<0.001, r=0.530, respectively). We also found a weak positive correlation between the EF and the degree of stiffness of the P and SM glands in the prelemon stimulation period (P=0.001, r=0.405; P<0.001, r=0.480, respectively). However, we did not find any significant correlation between other scintigraphic and elastographic parameters.
Conclusion: ARFI imaging may play a role in the determination of the EF of P and SM glands by measuring tissue elasticity changes with lemon stimulation. However, ARFI does not seem to be a suitable substitute for scintigraphy in the evaluation of the parenchymal function of P and SM glands.