影响前列腺激光消融的因素及临床意义

Influential Factors upon Laser Ablation for Benign Prostatic Hyperplasiaand their Clinical Significance

目的探讨影响激光作用于前列腺组织生物学效应的因素，指导改进激光手术操作。方法对４例拟行前列腺切除术的前列腺增生症患者，在开放手术前先以不同功率（３０、４５、６０、７０Ｗ）的Ｎｄ∶ＹＡＧ激光经尿道非接触式照射前列腺组织６０ｓ或９０ｓ，术后取切除的前列腺组织行光镜、电镜及免疫组化系列观察。结果受照射组织坏死区直径为８～１６ｍｍ。随激光功率增加，组织受损范围相应增加，但作用时间均为６０ｓ时，６０Ｗ和７０Ｗ两种功率造成的组织损伤范围大致相同；激光功率均为６０Ｗ时，照射时间由６０ｓ延长至９０ｓ，组织损伤范围也大致相同。当激光功率和作用时间恒定时，术中膀胱冲洗液流速慢者组织损伤范围大于流速快者。结论激光功率、照射时间及冲洗液流速是影响激光对前列腺组织生物学效应的重要因素，采用功率６０Ｗ、每点照射６０ｓ能产生较好的激光生物学效应；对不同治疗部位应采用不同功率和作用时间；常规四点照射不能保证激光对组织的作用深度和范围，应改为六点照射。

Objective To study the influential factors of laser effects on biological tissue in order to improve the methods of operation. Methods 4 patiens of benign prostatic hyperplasia were treated by transurethral noncontact laser(NdYAG) irradiation at various power (30 W, 45 W, 60 W, 70 W) and duration (60 s or 90 s) before prostatectomy. The prostate specimens removed from the operation were examined by light microscopy, electron microscopy and immunohistochemistry in series. Results The diameter of necrotic area of treated tissues was 816 mm. The injury extent was increased, while the laser power was higher, but when the treatment time was fixed at 60 s and the power ranged at 60 W or 70 W the injure diameters of the tissue were very close. When the laser powers was fixed at 60 W, and the treatment time was extended from 60 s to 90 s, the injury diameters of the tissue were close too. When laser power and treatment time were fixed the injury area of the tissue was larger in cases of the slower velocity than those in the faster. Conclusions Laser power, treatment time and velocity of wash fluid are very important influential factors of biological effects on laser ablation for benign prostatic hyperplasia. The better biogical effects are obtained with 60 W lasser power and 60 s/point. The various power, treatment time should be adopted at different areas of treatment. The conventional laser irradiations at four points could not be guaranteed, for the effective depth and size of the treated tissue, six points irradiation should be performed.