Effects of gender and age on the quantitative parameters of [99mTc]pertechnetate salivary gland scintigraphy in normal subjects

Aim To assess the effect of gender and age on [Tc-99m]pertechnetate salivary gland scintigraphy (SGS) in healthy subjects. Methods The study population consisted of 93 normal subjects (46 women, 47 men; age range 20-59 years). The subjects were categorized into eight (four female and four male) subgroups according to age decades. Dynamic SGS was performed after intravenous injection of 370 MBq [Tc-99m]pertechnetate. Anterior salivary gland images were acquired for 30 min. On the basis of the time-activity curves, three functional parameters were calculated for the parotid and submandibular salivary glands: (1) the first minute uptake ratio, (2) the maximum uptake ratio, and (3) the maximum secretion percentage. Results For women, all parotid and submandibular functional parameters had a peak in the fourth decade group. The comparison of four age groups in the female subjects showed significant differences, except for the third versus the fifth decades, at least for one parameter The number of significant differences was highest in the comparison between the second versus the fourth decades. Among men, the highest values for all parotid and submandibular parameters were in the second decade, except for the first minute uptake ratio in the submandibular gland. The number of parameters that were significantly different among the four age groups in men was lower than in women. The first minute uptake ratio of the submandibular gland had the most significant differences among the groups of male subjects. Conclusion Age and gender differences have a significant effect on salivary gland functions which is more apparent in women than in men.