New Modalities of Contact Nd:YAG Laser Endoscopy for General Application in the Gastrointestinal Tract

Abstract

It is generally recognized that fiberoptic endoscopy has both diagnostic and therapeutic uses and is one of the most common procedures in clinical gastroenterology. In the last decade, several endoscopic modalities for the treatment of gastrointestinal hemorrhage and neoplasms have been applied clinically. They include laser irradiation,1–5 electrocoagulation,6 topical injection, sclerotherapy, thermoprobes,7 and intubation of prosthesis.8 All of these procedures naturally have both advantages and disadvantages. Laser endoscopy is an unique procedure. Since the middle 1970s, Nd:YAG lasers have been applied using the noncontact method with the optical quartz fiber.1–5,8,9 There are distinct disadvantages of noncontact irradiation, such as the difficulty in keeping a constant distance from the tip of the quartz fiber to the lesion, allowing reliable tissue changes to occur related to the applied power. Furthermore, the quartz tip will be damaged when it comes into contact with tissue or blood. To overcome these disadvantages, the SLT contact method® with SLT endoprobes® directly connected to the quartz fiber was developed following reports of experimental research with the surgical probe, which was made of new ceramic materials.10–12 We initiated experimental and clinical studies of endoscopic Nd:YAG laser therapy, comparing the new SLT contact ceramic endoprobes with the single noncontact quartz fiber endoprobes, in order to evaluate the histologic effects and safety of each method. In this chapter, we discuss the possibilities of the clinical application of SLT contact endoprobes as a new endoscopic modality in the gastrointestinal tract.13–16