They can be divided into “slow methods” such as photodynamic therapy, cryotherapy and brachytherapy or fast methods: laser, argon plasma coagulation, and electrocautery. Differences relate to their mechanisms of action, onset of effect (immediate vs. delayed), depth of tissue penetration and complication pro le [12]. Fast methods will be the topic of this chapter.

Laser therapy normally integrates rigid bronchoscopic resection. This procedure is known worldwide as Laser Assisted Mechanical Resection (LAMR) and represents the safest and more effective way to obtain all potential effects of laser in bronchoscopy. Some authors use laser with the fexible bronchoscope with limited safety and ef cacy if compared to LAMR. The tissue–light interaction leads to thermal tissue damage with vaporization, coagulation, resection, or incision of obstructing lesions [13, 14].

Laser therapy was originally indicated for short endobronchial central airway lesions with a visible distal lumen. Bronchoscopists who become familiar with the technique will use it even in complete stenoses where the distal bronchial tree can only be reached using the suction tube and the rigid bronchoscope basing upon precise knowledge of the anatomy and preferably with support from CT scan images. In these cases, the combination of rigid bronchoscopy and laser ring is crucial. The technique is most commonly applied in cases of malignant intrinsic airway obstruction or in postintubation tracheal stenosis. The effects upon airway lumen size are usually immediate and accompanied by excellent control of bleeding. Laser is not useful for central airway obstruction caused by extrinsic airway compression.

Electrocautery and argon plasma coagulation also rely on thermal tissue destruction. With electrocautery, a high-frequency current is applied to the lesion with bipolar probes. When the current is directly applied to the tissue, heat develops and leads to tissue necrosis. Electrocautery is traditionally de ned as “the poor man’s laser” since it can mimic the effects of laser ring when vaporization or resection are needed with a less expensive equipment.

Argon plasma coagulation is a related therapeutic intervention. Argon gas is emitted through a fexible Tefon tube. This gas is ionized because of exposure to high-frequency current and an electrical arc is formed which allows for desiccation and tissue destruction. It is a valuable tool in treating super cial bleeding and debulking granulation tissue and tumors.

Electrocautery and Argon plasma coagulation are cheaper than Laser and may be performed using fexible bronchoscopy in patients under conscious sedation. Both penetrate tissue less than laser and while this reduces the extent of large tumor debulking, it also limits the risk of airway damage and perforation [12].

Indications, equipment, application, and outcomes of these techniques will be extensively discussed hereafter.

History and Historical Perspectives

Gustav Kilian, the so-called father of bronchoscopy, was the rst who introduced a tube into the trachea, in order to extract a small piece of pork bone from the right main bronchus of a German farmer in 1897 [15]. Few years later, in 1907 Chevalier Jackson realized a bronchoscope based on the instruments used for esophagoscopy [16].

However, the development of fexible bronchoscopy and the improvement of its use in the 1970s made the rigid bronchoscope less used and until the early 80s the endoscopic treatment of central airway obstructions was hazardous and often inadequate because of the high risk of bleeding and the short-term results provided. The introduction of endoscopic electrosurgery and cryotherapy partially succeeded in reducing the risk of bleeding, even though these techniques gave an unpredictable risk of damaging the adjacent healthy tissues. Cryotherapy was initially used in the 1970s in the treatment of inoperable endobronchial cancers, but in the following years it was more and more used with good results in effectiveness and safety [17].

The introduction of the endobronchial Nd-YAG laser in 1982 by Dumon [18] and the