Laser-assisted demucosalized gastrocystoplasty with autoaugmentation in a canine model.

Objectives: Laser-assisted autoaugmentation gastrocystoplasty has been performed successfully. Experiments were performed to determine the optimal laser for tissue welding during demucosalized autoaugmentation gastrocystoplasty using both a 1.9-microm diode and a 1.32-microm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser with and without thermal control.

Methods: Autoaugmentation gastrocystoplasty was performed on 18 female mongrel dogs. Anastomoses were performed by either suture or laser welding with a 50% human albumin solution. A 1.9-microm diode laser was compared with a 1.32-microm Nd:YAG laser with and without thermal control. In vivo canine bladder capacity measurements were performed both before gastrocystoplasty and at euthanasia. The animals were studied on days 4 and 14. Samples of the anastomotic area from each group were taken to measure tensile strength. Histologic samples were assessed for tissue damage.

Results: There was a significant increase in bladder volume in the 4-day group compared with pregastrocystoplasty values. Both the 1.9-microm diode laser and suture control dogs with the 14-day repairs had significantly more tensile strength than their 4-day counterparts. In contrast, no statistical difference was found between the 4 and 14-day 1.32-microm Nd:YAG groups. The suture control group had evidence of minor tissue devitalization at the anastomosis at both 4 and 14 days. The 1.9 and 1.32-microm laser groups both had evidence of tissue devitalization at 4 and 14 days. The 1.32-microm laser group had primarily severe tissue injury. The laser groups at 14 days demonstrated an inflammatory reaction that was localized to the albumin.

Conclusions: Demucosalized gastrocystoplasty with autoaugmentation can be safely and successfully performed with a 1.9-microm diode laser without significant differences in tensile strength when compared with suture controls. The 1.32-microm Nd:YAG laser can also be successfully used; however, the long-term results appear to be inferior to the 1.9-microm diode laser.