The presence of cervical lymph node metastasis in head and neck tumors is usually determined by manual neck palpitation. However, this method cannot ascertain whether carotid artery invasion is present or not. Actually, fixed lymph node metastasis means nothing but deep fascia invasion of the metastasis. Contrast CT scan, on the contrary, can present exact information about the carotid artery. We investigate the comparison between CT scan results and surgical results in this paper.