Experimental and clinical studies of ICG dye enhanced diode laser photosclerotherapy for esophageal varices

We developed ICG dye enhanced diode laser photosclerotherapy as preventive treatment for bleeding esophageal varices. Submucosal injection of wave length-specific dye (ICG: indocyanine green) could provide enhanced diode laser beam absorption selectively in the submucosal tissues around esophageal varices. First of all, we clarified the efficacy and safety of this new technique experimentally using dog's esophagus and then applied it in 6 cases of esophageal varices. In the experimental study, thermal injuries in the mucosa and submucosa were selectively induced without surface defects during irradiation. A month follow up endoscopy showed degenerated mucosa and submucosa to be replaced with fibrosis while no changes were observed in the muscle layer. Based on these findings, we therefore, applied this technique in 6 patients of esophageal varices after EVL treatment. Complete eradication was archieved within 2 weeks in all cases. A mild stenosis was seen in 2 patients, which was easily treated by balloon dilatation. It is concluded that ICG dye enhanced diode laser photosclerotherapy would be useful as a simple, safe and effective alternative to prevent bleeding from esophageal varices.