Prospective evaluation of office-based parotid ultrasound.

Abstract

Differentiation of parotid neoplasms from extraparotid upper cervical lesions is difficult by physical examination. The purpose of this report is to identify the role of office-based parotid ultrasound (US) in the evaluation of periauricular masses. A prospective database including the results of physical examination, office-based US, and the corresponding pathology was reviewed. Soft-tissue US was performed with a 7.5-mHz parallel probe with biplanar imaging. Thirty-eight patients were evaluated over a 28-month period (mean age. 45 years; range, 23-78 years). US demonstrated a mass within the substance of the parotid (n = 23, 61%), outside the parotid (n = 11, 29%), or diffuse parotitis (n = 4, 10%). Intraparotid masses were preauricular (n = 14), postauricular (n = 5), or upper cervical (n = 4) and were solid (n = 22) or cystic (n = 1). Patients with solid intraparotid masses underwent superficial (n = 20) or total parotidectomy (n = 2). Benign (n = 19) and malignant (n = 3) solid parotid nodules had similar US features of hypoechogenicity with posterior enhancement. Indistinct margins were noted in 3 of 3 malignant lesions as well as 15 of 19 benign nodules (P = .9). Extraparotid masses were confirmed to be nodal disease on the basis of observation with resolution (n = 3), fine-needle aspiration (n = 6), or surgical removal (n = 2) (mean follow-up, 6 months). Surgical office-based parotid US can delineate the location of periauricular mass lesions relative to the parotid gland. Benign and malignant lesions have a similar sonographic appearance.