[Volume Measurements of Human Parotid and Submandibular Glands]

Objective: To accurately measure the volume of normal human parotid and submandibular glands, establish the normal values of the volumes of the glands, and apply the technique in the diagnosis of swollen salivary glands of the patients with IgG4-related sialadenitis.

Methods: Two hundred and forty cases with normal parotid and submandibular glands who received CT examination were divided into 4 groups according to the age standards raised by the Society of Geriatrics Chinese Medical Association and WHO (2000) age standards . 3D CT images of parotid and submandibular glands were reconstructed by technique of volume rendering. Volumes of normal parotid and submandibular glands were measured and their normal values were analyzed. The volumes of swollen parotid and submandibular glands from 30 cases with IgG4-related sialadenitis were compared with the normal values.

Results: 3D images of parotid and submandibular glands were well established by volume rendering. The normal values(95%confidence interval, 95%CI) of CT volume of parotid gland were as follows: adolescent group of males: 16.993-20.975 cm(3), females: 13.908-16.696 cm(3); young group of males: 20.015-24.359 cm(3), females: 18.089-21.135 cm(3); middle-aged group of males: 28.638-35.122 cm(3), females: 19.588-22.474 cm(3); young elderly and elderly group of males: 28.792-35.082 cm(3), females: 28.783-34.909 cm(3). The normal values (95%CI) of submandibular gland were as follows: adolescent group of males: 7.202-8.852 cm(3), females: 6.494-8.126 cm(3); young group of males: 7.759-9.523 cm(3), females: 7.285-8.605 cm(3); middle-aged group of males: 8.423-10.177 cm(3), females: 7.905-9.309 cm(3); young elderly and elderly group of males: 8.310-10.510 cm(3), females: 7.003-8.203 cm(3). The volumes of parotid glands increased with age. but no significant change was found in those of submandibular glands. The volumes of the swollen glands from the patients with IgG4-related sialadenitis were significantly larger than those of the normal glands.

Conclusion: Volumes of the parotid and submandibular glands could be definitely and quantitively measured by CT volume rendering. The established normal values in this study could be taken as the reference for the diagnosis of parotid and submandibular gland enlargement .