New bronchoscopic treatment modalities for patients with chronic bronchitis.

Chronic bronchitis is a chronic, progressive disease that is difficult to treat. Despite much effort, patients remain highly symptomatic. Currently, a number of innovative bronchoscopic treatments for this disease are under investigation. Liquid nitrogen metered cryospray, bronchial rheoplasty and balloon desobstruction all aim to destroy the hyperplastic goblet cells and excess submucous glands using different strategies. These therapies are in an early phase of clinical research and larger randomised controlled trials are needed to confirm the pilot data available and to evaluate the treatment durability. The fourth technique, targeted lung denervation (TLD), aims to decrease the release of acetylcholine, which regulates smooth muscle tone and mucus production by ablating the parasympathetic nerves running alongside the main bronchi. Evaluation of this treatment is at a more advanced stage and promising effects on exacerbation frequency have been shown. However, confirmation of the benefit in improvement in chronic bronchitis symptoms is still needed.