MRI had been performed one day before and three days after radiotherapy in patients with lung cancer starting from october 1994. By means of analysis

we consider that RMI was very valuable in the following evaluations:1

the features of primary tumor; 2

hilar and mediastinal lymph nodes enlarqment; 3

differentiating primary masses and enlargment lymph vessels; 4

distinguishing masses from atelectasis; 5

the extension of chest wall invasion; and 6

making the distinction between radiation fibrosis and recureent or residual tumor.