Gray scale ultrasound of the parotid gland.

Gray scale ultrasonography permits markedly improved visualization of the parotid gland compared with bistable methods. The normal parotid is echogenic, similar in echo generation to thyroid tissue, but flatter anatomically. Ultrasound can detect a mass lesion in the area of the parotid gland and define whether it is intrinsic or extrinsic, but as yet has limited usefulness in determining the specificity of an abnormality.