Neodymium: YAG laser specifications for safe intravesical therapy

The depth of penetration of a laser beam is a critical factor in determining the therapeutic potential and risks of treatment. Variable parameters of laser energy were applied endoscopically in dog bladders. Although there was a clear trend toward greater depth of necrosis with increased energy, marked variability occurred within each set of energy specifications. Full thickness injuries with penetration depths up to five mm. were observed in some animals at all energy levels above 120 joules. A number of variables affect the penetration depth of a Nd:YAG laser, some of which are difficult to control with precision in an endoscopic setting.