Partial nephrectomy using the Nd:YAG Laser: A comparison of the 1.06 μ and 1.32 μ lasers employing different delivery systems

A comparative study of the 1.06 μ and the 1.32 μ Nd:YAG laser using a variety of delivery systems (focusing handpiece, freehand GI quartz fiber, or frosted laser scalpel) was undertaken to determine the usefulness of these modalities in performing partial nephrectomies in dogs. Variables evaluated included total operative time, total joules expended, estimated amount of blood loss, and extent of renal tissue damage. The contact laser scalpel provided the greatest precision and speed, but no hemostasis, and is therefore inappropriate for parenchymal renal surgery. Evaluation of the other delivery systems showed no discernible differences in the extent of renal damage that could be attributed to either wavelength or wattage used. The usual depth of acute renal damage ranged from 1.0 mm to 1.8 mm when tissue was fixed immediately after completing the polar nephrectomy, but the damage had extended to 3.0 mm when tissue was examined after 6 weeks. No consistent differences in extent of cellular damage could be demonstrated between the renal cortex and medulla. The lens system inherent in the focusing handpiece limited the total power (60 watts) that could be employed and surgery proceeded at a slower pace and required a greater expenditure of energy. Likewise, the maximal power that could be applied using the 1.32 μ laser was 25 watts and surgery also proceeded at a slower pace. Therefore, it was concluded that the optimal delivery system studied was the hand-held GI quartz fiber, using the 1.06 μ, which provided maximum wattage, allowing surgery to proceed rapidly with minimal side effects (absence of 'flashing', heat build-up) to the operative personnel and without increased tissue damage to the remaining renal parenchyma.