The parotid gland is the largest of the three major salivary glands, situated just in front of and below each ear. It produces saliva that enters the mouth through a duct (Stensen’s duct) that opens inside the cheek near the upper molars. On ultrasound, the normal parotid gland appears as a homogeneous, moderately echogenic structure. Sonography is the first-line imaging tool for evaluating parotid lumps and can detect a wide range of conditions including benign tumors (pleomorphic adenoma, Warthin tumor), malignant tumors, salivary stones (sialolithiasis), infections (sialadenitis), and cysts. The relationship of a mass to the facial nerve, which passes through the gland, is clinically important but cannot be directly visualized by ultrasound.
Sonography Term