Endoscopic argon laser photocoagulation of small sessile colonic polyps.

The availability of flexible quartz wave ¿uides allowing introduction of argon laser energy through endoscopes suggests the possibility of ablation of colonic mucosal lesions by this technique. To ascertain the effects of the argon laser on the colon, penetration depth and perforation studies were conducted in dogs. At 250 joules/cm2 energy density, less than 50% muscularis externa injury was noted in 29 of 42 lesions. No perforation was noted. Healing was complete in 8 days. The time required for deliberate perforation with the catheter firmly pressed against the wall of a distended inflated colon using 2 W argon laser applied continuously was 41 +/- 13 sec, N = 53. In a human study of 15 small sessile polyps ablated by laser and the colon examined 4 days later at colectomy, no penetration of the laser beneath the submucosa was noted. In 11 patients with Gardner's syndrome 211 polyps have been removed in 18 treatments without complication. These encouraging results suggest the continued study of this endoscopic modality in the treatment of mucosal lesions of the colon.