Gastric ulcer healing after laser treatment in dogs.

Endoscopic laser photocoagulation of ulcers is increasingly used to produce hemostasis in patients who are actively bleeding or in patients with stigmata of recent hemorrhage. Little information is available describing ulcer healing rates after laser treatments. The aim of this study was to compare the healing rates of gastric ulcers treated with laser energy (Nd:YAG) with untreated ulcers in dogs. Two standard gastric ulcers (12-14 mm diameter) were created in each dog stomach using an ulcer maker (Quinton) under endoscopic guidance and one was randomly selected for laser treatment (L), while the other served as control (C). Ten laser spots were applied circumferentially around the ulcer crater with a mean energy of 595 J per ulcer. Ten dogs were studied; four of which were sacrificed after one week and six after two weeks. Healing of treated ulcers was compared with that of control ulcers and expressed as a percentage of the initial ulcer surface. Histologic injury and reepithelialization were scored by two pathologists unaware of the treatment. Laser-treated ulcers healed significantly slower than untreated ulcers at one week (53% L vs 94% C, P less than 0.05) and histologic injury was greater in ulcers treated with laser photocoagulation. At two weeks, only 82% of the laser-treated ulcer surface was healed in comparison with 94% (P less than 0.05) healing in untreated ulcers, although the mean histologic injury score was not different at two weeks. Reepithelialization was decreased both at one week (11% L vs 71% C, P less than 0.01) and at two weeks (75% L vs 100% C, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)