尿路狭窄に対するレーザー治療

抄録

The goal of our study is to develop a simple and safe laser treatment of the urinary tract stricture without the recurrent stenosis. To select of the therapeutic laser with less probability of the recurrent stenosis after the treatment, we compared between Ho: YAG laser (pulsed waveform) and UV Ar laser (continuous waveform), which have almost equal optical absorption of tissues and the capability of fiber delivery. Although the Ho:,YAG laser ablation efficiency was lower than that by UV Ar laser, histological examination revealed that the thermally damaged layer by Ho:,YAG laser was thinner than that by UV Ar laser. This thermal conduction may cause the lower ablation efficiency and thinner thermally damaged layer comparing to UV Ar laser. The result indicated the usefulness of Ho: YAG laser for the treatment of ureteral stricture. Furthermore, Ho: YAG laser has advantage in low maintenance cost due to solid-state laser and has is commercially available. The fibrotic ureteral stricture was successfully treated using Ho: YAG laser and Multi-fiber catheter. The ureter was kept open for 6 months without indwelled stent catheter. The treatment of Ho: YAG laser through the multi-fiber catheter may be useful for the urinary tract stricture.