Ultrasound Examination of Normal Anatomic Variations of Major Salivary Glands

Abstract

Introduction: Accurate knowledge of anatomic characteristics and variations of sonographic view is important to better understand the imaging findings for a more precise examination. The present study therefore aimed to examine the variations in sonographic view of the normal anatomy of salivary glands and the important anatomical structures around them. Material and Methods: In this study, 200 cases of parotid, submandibular, and sublingual salivary glands in 100 healthy volunteers were scanned using ultrasound. The variables studied included echogenicity and echo-pattern of all three pairs of salivary glands, borders of submandibular and sublingual glands, and the possibility of observing common tissues, which were evaluated in all examinations. Results: Eighty-three female and 17 males were surveyed between the ages of 6 and 61. Echogenicity of the sublingual, submandibular, and parotid glands was hyperechoic in 94.5%, 92.5%, and 84.5%; and hypoechoic in 5.5%, 7.5% and 15.5%, respectively. Also, echo-pattern of the sublingual, submandibular, and parotid glands was homogeneous in 78.5%, 80.5%, and 92%; and heterogeneous in 21.5%, 19.5% and 8%, respectively. The border of sublingual glands was well, ill, and poor in 36.5%, 43.5%, and 20%, respectively. Also, the border of submandibular glands was well, ill, and poor in 56%, 24.5%, and 19.5%, respectively. In the possibility of observing sublingual gland-specific variables, the highest and lowest frequency was related to geniohyoid with 73% and genioglossus with 50.5%, respectively. In submandibular glands, the highest and lowest frequency was of posterior digastric belly with 69.5% and hyoglossus muscle with 60%, respectively. Also, in parotid gland, the highest and lowest frequency was related to lymph nodes with 56% and external carotid artery with 32%, respectively. Conclusion: There were significant variations in the sonographic characteristics of all three pairs of salivary glands of healthy volunteers, indicating that accurate knowledge of the glands is necessary for reliable ultrasound examination.