One-way valves to treat severe emphysema
Researchers at the University of Alabama at Birmingham are investigating a one-way valve for its ability to improve lung function. The valve can be placed in the lungs of patients with severe emphysema and is being hailed as a method that can reduce lung volume without surgery.
Lung-volume-reduction surgery, in which over-inflated, diseased parts of the lung are surgically cut away, allowing the lung to return to a more normal size is a traditional path many take to combat damaging the lungs further. While the surgery is effective, it is not commonly performed in the United States due to the associated risks of pulmonary or cardiac complications.
Developed as a non-surgical option, the one-way valve, formerly known as the Zephyr endobronchial valve, is a minimally invasive procedure. Using a bronchoscope inserted in the airway, several small, one-way valves are placed in the lungs to block airflow to diseased regions. This allows healthy regions to expand and function more efficiently, enabling better breathing and improving quality of life.
"The idea behind all lung-volume-reduction procedures is to reduce the volume in the lung and allow the diaphragm to return to its normal shape and function," said Mark Dransfield, M.D., associate professor in the Division of Pulmonary, Allergy and Critical Care Medicine and medical director of the UAB Lung Health Center. "We're looking for a less invasive way to achieve that goal without the risks inherent in surgery."
So far the valves have been placed in four patients diagnosed with severe emphysema. Dransfield also adds that not all patients with severe emphysema are good candidates for the implantation, noting that “patients need to have enough healthy lung tissue so that blockage of the most diseased and damaged areas and the reduced lung volume will allow the healthier areas to function more normally.”
While there is no cure for emphysema, Dransfield insists that “clinical studies in Europe indicate majority of patients see a significant improvement in lung function, exercise tolerance and quality of life.”
