Abstract
Background : the prediction on changes in the lung function after lung surgery would be an important indicator in terms of the operability and postoperative complications. In order to predict the postoperative FEV1 - the commonly used method for measuring changes in lung function- a comparison between the quantitative CT and the perfusion lung scan was made and proved its usefulness. Material and Method : The subjects included 22 patients who received perfusion lung scan and quantitative CT preoperatively and with whom the follow-up of PFT were possibles out of the pool of patients who underwent right lobectomy or right pneumonectomy between June of 1997 and December of 1999. The FEV1 and FVC were calibrated by performing the PFT on each patient and then the predicted FEV1 and FVC were calculated after performing perfusion lung scan and quantitative CT postoperatively. The FEV1 and FVC were calibrated by performing the PFT after 1 week and after 3 momths following the surgery. Results : There was a significant mutual scan and the actual postoperative FEV1 and FVC at 1 week and 3 months. The predicted FEV1 and FVC(pneumonectomy group : r=0.962 and r=0.938 lobectomy group ; r=0.921 and r=913) using quantitative CT at 1 week postoperatively showed a higher mutual relationship than that predicted by perfusion lung scan(pneumonectomy group : r=0.927 and r=0.890 lobectomy group : r=0.910 and r=0.905) The result was likewise at 3 months postoperatively(CT -pneumonectomy group : r=0.799 and r=0.882 lobectomy group : r=0.934 and r=0.932) Conclusion ; In comparison to perfusion lung scan quantitative CT is more accurate in predicting lung function postoperatively and is cost-effective as well. Therefore it can be concluded that the quantitative CT is an effective method of replacing the perfusion lung scan in predicting lung function post-operatively. However it is noted that further comparative analysis using more data and follow-up studies of the patients is required.