A number of minimally invasive techniques have been described to achieve lung volume reduction, without the need for open surgery. The impetus has been the significant morbidity and mortality with conventional open lung volume surgery. 

Various bronchoscopic techniques have been promoted including the follwing

• one-way valves, which allow air to exit but not enter
• airway bypass stents, which create an extra-anatomical pathway for air to exit
• biologic substances or thermal ablation to seal the emphysematous lung
• endobronchial elastic coils, which mechanically cause LVR

Many of these remain experimental. The above images demonstrate endobronchial elastic coils, which are deployed through bronchoscopy. The theory is that by being elastic, they retract and lead to lung volume reduction over time.