Fang Liu MD, Presenter: Nothing to Disclose

Ping Han MD, Abstract Co-Author: Nothing to Disclose

Bo Liang, Abstract Co-Author: Nothing to Disclose

Zhiliang Tian, Abstract Co-Author: Nothing to Disclose

Jie Xiao MD, Abstract Co-Author: Nothing to Disclose

Gansheng Feng MD, PhD, Abstract Co-Author: Nothing to Disclose

To evaluate the usefulness of quantitative CT (QCT) in predicting postoperative pulmonary function in patients with lung cancer.

31 patients with lung cancer scheduled for an operation (2 of them got single pneumoectomy, 23 lobectomy, 3 segments resection, 1 lobe and segment resection, and 2 wedge resection) were included in the study. Prior to operation QCT was performed in all subjects, and conventional pulmonary function test using spirometry was done before and two months after the operation. QCT scan was obtained with Siemens Somatom Plus4 CT scanner, and the functional lung density index as well as volume were analysed by Pulmo software supplied with the equipment. In this study -910HU ~ -600HU was chosen as the evaluation range for functional lung tissue. The pixel index of this range was taken as functional lung density index, and the total funtional lung volume (TFLV) and regional (to be resected) functional lung volume (RFLV) were calculated from the product of the density index and volume. Forced vital capacity (FVC), the first second forced expiratory volume (FEV1) as well as FVC% and FEV1% (ratio to reference values of the matched population) were derived from conventional spirometry. The predicted postoperative FVC and FEV1 by QCT were calculated from FVC • [1-(RFLV/TFLV)] and from FEV1 • [1-(RELV/TFLV)], respectively.

The overall results showed a good correlation between the predicted values derived from QCT and the postoperative values from the conventional spirometry (r=0.87, 0.81, 0.85 and 0.81 for FVC, FEV1, FVC% and FEV1%, respectively, P<0.01). There was no significant difference between the predicted values by QCT and those determined by spirometry in terms of the pulmonary function (mean difference for FVC 0.18 L, FEV1 0.19 L, FVC% 5.0% and FEV1% 5.7%, respectively). In 5 cases the predicted FVC and FEV1 were slightly overestimated and in 9 cases slightly underestimated.

Pre-operative QCT, combined with spirometry can provide comparable data on postoperative lung function in comparison with postoperative spirometry, therefore, QCT can serve as a useful tool to predict postoperative pulmonary function in patients with lung cancer.

To evaluate the usefulness of quantitative CT (QCT) in predicting postoperative pulmonary function in patients with lung cancer.

31 patients with lung cancer scheduled for an operation (2 of them got single pneumoectomy, 23 lobectomy, 3 segments resection, 1 lobe and segment resection, and 2 wedge resection) were included in the study. Prior to operation QCT was performed in all subjects, and conventional pulmonary function test using spirometry was done before and two months after the operation. QCT scan was obtained with Siemens Somatom Plus4 CT scanner, and the functional lung density index as well as volume were analysed by Pulmo software supplied with the equipment. In this study -910HU ~ -600HU was chosen as the evaluation range for functional lung tissue. The pixel index of this range was taken as functional lung density index, and the total funtional lung volume (TFLV) and regional (to be resected) functional lung volume (RFLV) were calculated from the product of the density index and volume. Forced vital capacity (FVC), the first second forced expiratory volume (FEV1) as well as FVC% and FEV1% (ratio to reference values of the matched population) were derived from conventional spirometry. The predicted postoperative FVC and FEV1 by QCT were calculated from FVC • [1-(RFLV/TFLV)] and from FEV1 • [1-(RELV/TFLV)], respectively.

The overall results showed a good correlation between the predicted values derived from QCT and the postoperative values from the conventional spirometry (r=0.87, 0.81, 0.85 and 0.81 for FVC, FEV1, FVC% and FEV1%, respectively, P<0.01). There was no significant difference between the predicted values by QCT and those determined by spirometry in terms of the pulmonary function (mean difference for FVC 0.18 L, FEV1 0.19 L, FVC% 5.0% and FEV1% 5.7%, respectively). In 5 cases the predicted FVC and FEV1 were slightly overestimated and in 9 cases slightly underestimated.

Pre-operative QCT, combined with spirometry can provide comparable data on postoperative lung function in comparison with postoperative spirometry, therefore, QCT can serve as a useful tool to predict postoperative pulmonary function in patients with lung cancer.

Liu, F, Han, P, Liang, B, Tian, Z, Xiao, J, Feng, G, Usefulness of Quantitative CT to Predict Postoperative Pulmonary Function in Patients with Lung Cancer.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4414002.html