[Quantitative analysis of age-related changes of human major salivary glands using magnetic resonance imaging].

ABSTRACT

OBJECTIVE: To analyze the age-related characteristics of volumes, signal intensities (SIs) of T1-weighted images (T1WI), T2-weighted images (T2WI) and apparent diffusion coefficients (ADCs) of three major salivary glands. METHODS: A total of 300 subjects with normal salivary glands were divided into 4 different age groups and examined with a 1.5 T magnetic resonance (MR) unit. T1WI, T2WI and diffusion-weighted MR images (DW MRI) were obtained and bilateral parotid, submandibular and sublingual glands segmented manually. The volumes, T1WI, T2WI SIs and ADCs of three major salivary glands were measured. And the relative SIs (RSIs) were assessed by comparing with cerebrospinal fluid. RESULTS: The volumes, T1WI and T2WI RSIs of parotid glands were significantly correlated with age (P < 0.01) and showed similar significant tendencies of growing from minority to middle age and decreasing slightly after old age. Significant differences existed between minority and middle age groups in all above-mentioned parameters (P < 0.01). The ADCs of submandibular glands also showed that there was a significant difference between the minority and middle age groups (P < 0.01). CONCLUSION: MRI may be applied for studying the morphological and functional changes of normal major salivary glands with aging. Thus clinical rationales can be provided for assessing the subjects of any age during salivary gland imaging and aging-related researches.