The purpose of this study was to develop objective preoperative selection methods for predicting outcome in patients undergoing thoracoscopic
laser ablation of emphysematous pulmonary
bullae. Initial radiographic presentation was correlated with physiologic function both before and after the operation in 24 patients entered into a prospective clinical protocol for evaluation of
carbon dioxide laser treatment of emphysematous pulmonary
bullae. Nineteen surviving patients underwent follow-up evaluation 1 to 3 months after the operation. Pulmonary function test results showed improvements in spirometry (forced vital capacity increased 0.82 +/- 0.125 L, forced expiratory volume in 1 second increased 0.36 +/- 0.07 L, and maximum voluntary ventilation increased 11.69 +/- 2.6 L/m; p < 0.002); airway resistance decreased by 0.9 +/- 0.35 cm of water/L per second, and specific conductance increased 0.019 +/- 0.006 L/cm H2O per second (p < 0.02). Lung volumes improved (residual volume decreased 1.25 +/- 0.23 L, p < 0.001) without significant change in resting gas exchange. Quantitative radiographic grading of extent of preoperative pulmonary
bullae correlated well with response to
laser treatment in patients with preoperative and postoperative studies. Patients with large
bullae accompanied by crowding of adjacent lung structures, upper lobe predominance, and minimal underlying
emphysema had greatest improvement in pulmonary function results with
laser bullae ablation (p < 0.05). However, some patients with multiple smaller
bullae and diffuse
emphysema also demonstrated objective improvement after operation. Quantitative radiographic analysis of the extent of bullous disease and the degree of associated
emphysema can be used to determine short-term postoperative pulmonary response and may be useful in selecting future thoracoscopic
laser bullae ablation candidates. Additional follow-up will be necessary to further improve selection criteria and help define the long-term role of thoracoscopic
laser treatment of bullous
emphysema.