Lung volume reduction surgery, or LVRS, can improve the quality of life for certain COPD and emphysema patients. Parts of the lung that are particularly damaged by emphysema are removed, allowing the remaining, relatively good lung to expand and work more efficiently. The beneficial effects are correlated with the achieved reduction in residual volume. Conventional LVRS involves resection of the most severely affected areas of emphysematous, non-bullous lung (aim is for 20-30%). This is a surgical option involving a mini-thoracotomy for patients suffering end stage COPD due to underlying emphysema, and can improve lung elastic recoil as well as diaphragmatic function.