作者对10例腮腺肿瘤、口咽部肿瘤、鼻咽癌及从鼻腔向颅底进展的肿瘤作了MRI检查。1.腮腺肿瘤:因肿瘤性质不同,信号强度稍有不同,但从信号强度来诊断肿瘤组织学特征将是很困难的。如腮腺多形性腺瘤在MRI图像上可见到境界清晰的圆形肿瘤图像,T_1加权像呈低强度信号,T_2加权像呈高强度信号。但这信号强度也见于腮腺囊肿、腮腺淋巴结炎等。MRI可清晰地显示腮腺癌的肿瘤被膜外 The authors performed MRI on 10 cases of salivary gland tumors, oropharyngeal tumors, nasopharyngeal carcinoma, and tumors that progressed from the nasal cavity to the skull base. 1. Salivary gland tumors: Because of the different nature of the tumor, the signal intensity is slightly different, but it will be very difficult to diagnose the histological characteristics of the tumor from the signal intensity. For example, in the parotid gland pleomorphic adenoma on the MRI image, a clear-cut circular tumor image can be seen. The T_1-weighted image shows a low-intensity signal, and the T_2-weighted image shows a high-intensity signal. However, the signal intensity is also seen in parotid cysts, salivary gland lymphadenitis and so on. MRI clearly shows the tumor capsule outside the parotid gland carcinoma