Preliminary Study of Age-Related Changes in Apparent Diffusion Coefficient Values of Normal Salivary Glands

Objective: This study aimed to assess age-related changes in the apparent diffusion coefficient (ADC) values of the salivary glands using diffusion-weighted imaging. Methods: This retrospective study included patients who underwent magnetic resonance imaging between November 2017 and March 2018. The participants of this study comprised 142 participants (50 males and 92 females) aged 8–88 (mean age 46.78). The relationship between the age group of the explanatory variable and ADC values, which are criterion variables whose normality was confirmed by the Kolmogorov–Smirnov test, was analyzed using Pearson and Spearman's correlation coefficients. The p value was set at 0.05. Results: No correlation was found between age and ADC values in the submandibular glands (p = 0.411, r = −0.07). A negative correlation was observed in the parotid gland (p < 0.001, r = −0.369). The mean and median ADC for the submandibular and parotid glands did not differ between men and women (p = 0.224 and p = 0.053, respectively). Conclusion: This study indicated a significant negative correlation between increasing age and the normal ADC values of the parotid glands. These findings may be useful for the diagnosis of salivary gland diseases.