Bullectomy can be associated with significant improvement in dyspnea as long as patients are appropriately selected. This selection process begins with clinical history and determination of the size and location of the bulla. If a patient has a smaller bulla, which is less than 30% of the volume of the hemithorax, the dyspnea is unlikely to be related to the bulla and its excision is probably not indicated. Laros et al determined that for successful bullectomy, the bulla must occupy at least 50% of the hemithorax and show definite displacement of adjacent lung tissue. In addition, there must be no vanishing lung syndrome nor chronic purulent bronchitis. Wesley et al added that there should be radiologic evidence of compressed lung tissue that can be re-expanded by removal of the bulla, and that there should be evidence of regional imbalance with poor perfusion on the side of the bulla and relatively good perfusion on the contralateral side.