Matsumoto T, Miki M, Mamiya Y, Hirata T, Shimizu H, Tochimoto M, Ito T, Aika T
Nihon Hinyokika Gakkai Zasshi. 1989 Sep;80(9):1278-85. doi: 10.5980/jpnjurol1989.80.1278.
Ultrasound lithotriptors (USL) and electrohydraulic lithotriptors (EHL) are representative lithotriptors for endoscopic elimination of upper urinary tract stones. However, they have some disadvantages. For example, USL can not be used with flexible scopes and EHL can cause unexpected tissue injury. To overcome these problems, the pulsed dye laser lithotriptor (MDL-1, Candera Co.) was developed. The characteristics of this laser lithotriptor and its direct effects on tissue was investigated. This pulsed dye laser lithotriptor generates a 504 nm wavelength green light beam by using a combination of a xenon flash lamp and the greenish dye composed of coumarin solution. The maximum output energy is 60 mJ/pulse and the pulse duration is 1.5 microsecond. The pulse rate can be varied from 1 to 20 Hz. First, the intensity of the shock wave was measured by using a combination of a piezoelectric element and an oscilloscope, and then, the results were compaired with those obtained by a similar experiment with an EHL. The average intensity of the shock wave was 54.4 mW under the conditions of 40 mJ/pulse of output energy and 10 Hz of pulse duration. On the other hand, the EHL generated an average of 54.7 W under the conditions of 400 mJ/pulse output energy. Then, fragmentation of various kinds of urinary stones in saline solution was performed. The results showed that this lithotriptor could fragment almost all kinds of stones except cystine stones. Then, hen's eggs were used to observe the effect if laser bean influenced on the organism immediately behind the photoradiated object. Only the egg shell was demolished but the egg membrane below the eggshell did not undergo any change. After these experiments, skin, liver, kidney and urinary bladder of nude mice and human prostatic urethral mucosa in case of TUR-P were irradiated by this laser. The results showed that laser energy caused slight penetration and localized hemorrhage from the surface of epithelium to subcutaneous tissue. It was confirmed that these effects were generated when the tip of the quartz fiber was in direct contact with the object.(ABSTRACT TRUNCATED AT 250 WORDS)
超声碎石机（USL）和液电碎石机（EHL）是用于内镜下清除上尿路结石的代表性碎石机。然而，它们存在一些缺点。例如，USL不能与软性内镜配合使用，且EHL会导致意外的组织损伤。为克服这些问题，研发了脉冲染料激光碎石机（MDL-1，Candera公司）。对该激光碎石机的特性及其对组织的直接影响进行了研究。这种脉冲染料激光碎石机通过结合氙闪光灯和由香豆素溶液组成的绿色染料产生波长为504nm的绿色光束。最大输出能量为60mJ/脉冲，脉冲持续时间为1.5微秒。脉冲频率可在1至20Hz之间变化。首先，使用压电元件和示波器组合测量冲击波强度，然后将结果与用EHL进行的类似实验所得结果进行比较。在输出能量为40mJ/脉冲、脉冲频率为10Hz的条件下，冲击波的平均强度为54.4mW。另一方面，在输出能量为400mJ/脉冲的条件下，EHL产生的平均强度为54.7W。然后，在盐溶液中对各种尿路结石进行碎石。结果表明，除胱氨酸结石外，该碎石机几乎能粉碎所有类型的结石。然后，用鸡蛋观察激光束对光辐射物体后方生物体的影响。仅蛋壳被破坏，但蛋壳下方的卵膜未发生任何变化。这些实验之后，用该激光照射裸鼠的皮肤、肝脏、肾脏和膀胱以及经尿道前列腺电切术（TUR-P）患者的人前列腺尿道黏膜。结果表明，激光能量引起从上皮表面到皮下组织的轻微穿透和局部出血。证实当石英纤维尖端与物体直接接触时会产生这些效应。（摘要截选至250字）
