CT and US evaluation of mass lesions in the salivary region

The usefulness of computed tomography (CT) and ultrasonography (US) was compared in the evaluation of salivary masses in 78 patients with 49 benign tumors, 15 malignant tumors, 12 inflammatory masses and 2 cases of lymphadenopathy. All masses were detected by CT and US. CT and US accurately diagnosed the salivary gland origin except in 2 cases of lymphadenopathy. CT differentiation between superficial and deep lobe tumors agreed with surgical findings in 36 of 43 parotid tumors. US differentiation was correct in 32 of 39 parotid tumors. The most reliable findings for differentiating between benign and malignant tumors were whether or not the tumor margin was sharp and the tumor border was smooth. In the scoring for differentiation of malignant tumor from benign tumor, accuracy was 88% by CT, and 86% by US. Acute sialoadenitis closely mimicked a malignant tumor on CT and US, and clinical information was necessary for diagnosis. Chronic sialoadenitis was usually accompanied with calculi, and postcontrast CT demonstrated moderate enhancement effect of the enlarged gland. Intraglandular lymphnode accompanied with benign tumor was detected only by US. CT and US are complementary methods in the assessment of the salivary masses and US is recommended as the primary method because no radiation is used. (author)