Er:YAG laser ablation of prairie dog gallbladder epithelium for the prevention of gallstones

We hypothesized that laser ablation of gallbladder epithelium would prevent gallstone formation in prairie dogs. An Er:YAG laser (λ = 2.94 μm) was used to ablate the gallbladder epithelium of 24 prairie dogs; 20 sham‐irradiated and 12 non‐operated prairie dogs served as controls. Prairie dogs were sacrificed at time periods of 4 days, 2 weeks, and 8–12 weeks and evaluated for the presence of gallstones and cholesterol crystals. Laser‐irradiated gallbladders demonstrated a lower rate of gallstone formation at 8–12 weeks than the sham‐irradiated gallbladders (39% vs. 79%: P <.02). Crystal formation, however, was not different between laser‐irradiated (88%) and sham‐irradiated (100%) animals. The laser‐irradiated group had less epithelium than the non‐operated group at all time periods (P ≤.002) and compared to the sham‐irradiated group at 4 days and 8–12 weeks (P ≤.001). These data suggest that laser ablation of gallbladder epithelium can reduce the rate of gallstone formation although this effect may be temporary. © 1994 Wiley‐Liss, Inc.