PREOPERATIVE SCREENING FOR LUNG-VOLUME REDUCTION SURGERY - USEFULNESSOF COMBINING THIN-SECTION CT WITH PHYSIOLOGICAL ASSESSMENT

OBJECTIVE, This study was performed to assess the usefulness of preope rative thin-section CT alone and in combination with physiologic measu rements in emphysema patients being evaluated for lung volume reductio n surgery. SUBJECTS AND METHODS, Six 1-mm collimation sections through the chest were obtained in 20 patients being evaluated for lung volum e reduction surgery, Extent and severity of emphysema were assessed by visually scoring the images. CT scores ranged from 0 to 144. Inspirat ory resistance was measured in 12 of 20 patients and was also used to discriminate between responders (change in forced expiratory volume in 1 sec, greater than or equal to 150 mi after surgery) and nonresponde rs (change in forced expiratory volume in 1 sec, <150 mi after surgery ). RESULTS, Four of 20 patients with mild emphysema as revealed by thi n-section CT (scores of <50) did not improve lung function after lung volume reduction surgery. Eight of the remaining 16 patients with mode rate to severe emphysema as revealed by thin-section CT (scores of >50 ) underwent inspiratory resistance measurement. Those seven patients w hose inspiratory resistance measurement exceeded 8.5 cm H2O/l per seco nd did not respond favorably to lung volume reduction surgery (change in forced expiratory volume in 1 sec, <150 mi). The remaining five pat ients whose inspiratory resistance measurement was less than 8.5 cm H2 O/l per second responded favorably to lung volume reduction surgery. T hus, only five of the 20 patients showed improvement in forced expirat ory volume in 1 sec after surgery. CONCLUSION. Our data suggest that a mong patients with moderate to severe emphysema who are being examined for lung volume reduction surgery, the combination of radiologic and physiologic assessment is more accurate for predicting a favorable res ponse to lung volume reduction surgery than radiologic assessment alon e. However, in patients with chronic obstructive pulmonary disease by the American Thoracic Society criteria, mild emphysema as revealed on thin-section CT virtually precludes further workup because these patie nts are unlikely to respond favorably to lung volume reduction surgery .