Abstract
Computed tomography combined with sialography (CT-sialography) was performed before the operation on 30 patients with parotid gland tumors. The valuable information obtained by CT-sialography is the determination of the location of the tumor in relation to the facial nerve. But CT-sialography has two disadvantages. One is the possibility of the appearance of false tumor because of the space of external carotid artery and retromandibular vein or because of insufficient injection of contrast medium. Another is the difficulty of diagnosis of invaded lesion of high grade malignant tumor and cystic tumor. Indication of CT-sialography must be selected carefully.