[Simplified prediction of postoperative lung function by plain chest roentgenogram in patients with primary lung cancer--in correlation to postoperative respiratory complications].

For the purpose of simplification of prediction of postoperative lung function, we studied to predict lung function by analizing the frontal and lateral view of chest plain roentgenogram and investigate the correlation to respiratory complication on 111 patients with lung cancer. According to TNM classification of lung cancer, prediction was performed as follows. Predicted postoperative lung function = [(42-number of resected subsegments)/(42-number of occupied subsegments)] x preoperative VC or FEV1.0. In this formula, 42 was the number of functioning subsegments of whole lung (right: 22, left: 20), and then preoperative occupied subsegments was ordered by T factor, where T1 lesion in lung field was prescribed as 1 subsegment and T2 was more than 2 subsegments respectively in plain chest roentgenogram. And also, on the patients having hilar lesions, it was required to calculate the number of subsegments in atelectasis, peripheral obstructive pneumonia and/or partial emphysematous change due to intrabronchial lesions. There was uniformly positive correlations in VC (R = 0.7949) and FEV1.0 (R = 0.8235) of the patients studied respectively. The patients having pneumonectomy showed tendency of over estimation, on the other hand, the patients having resection of a few segments showed under estimation. To predict the postoperative respiratory condition, we calculated the predicted post-operative %VC and %FEV1.0 for predicted preoperative normal VC and FEV1.0. Above the al, we tried to investigate the correlation with predicted postoperative %VC, %FEV1.0 and postoperative respiratory complications.(ABSTRACT TRUNCATED AT 250 WORDS)