Endobronchial valves reduce the flow of air into the treated lobe during inspiration whilst allowing secretions and air to be expelled from that region during expiration. Its intention is to cause localized atelectasis in the target lobe, matching the size of the lungs to the size of the thorax containing them, thereby causing improvement in lung function, exercise tolerance, dyspnea, and quality of life​.

Acknowledgement: Dr Theodore Lau