Bronchial Thermoplasty, delivered by the Alair™ System, is a treatment for severe asthma approved by the FDA in 2010 involving the delivery of controlled, therapeutic radiofrequency energy to the airway wall, thus heating the tissue and reducing the amount of smooth muscle present in the airway wall. This treatment has been shown to result in acute epithelial destruction with regeneration observed in the epithelium, blood vessels, mucosa and nerves. However, airway smooth muscle has demonstrated almost no capacity for regeneration, instead being replaced by connective tissue. The treatment has been shown to be safe and effective over at least five years.