Dowlatshahi K, Bangert J D, Haklin M F, Rhodes C K, Weinstein R S, Economou S G
Department of General Surgery, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois 60612.
Lasers Surg Med. 1990;10(4):322-7. doi: 10.1002/lsm.1900100404.
In the past, interstitial laser therapy frequently has failed because of the damage to the bare fiber tip due to intense heat generated at the point of contact. Using a rat mammary tumor model, we describe a method of placing a 600 micron fiber inside a gauge 19 needle cannula after its insertion into the tumor. With this device continuous wave Nd:YAG laser is delivered to the target tumor while 0.9% saline flows para-axially into the tumor. Significant coagulation necrosis was induced with 500 joules at 5 watts, 100 seconds and 1 cc per minute of saline while the needle-fiber is pulled out of the tumor by 10 mm. The mean transmission loss after 500 joules was 2% in ten experiments. The tumor edema due to 1.5 ml of saline was transient. We conclude that successful hyperthermic coagulation necrosis by Nd:YAG laser can be achieved with minimal transmission loss by employing the above technique.
过去，间质激光治疗常常失败，原因是接触点产生的强烈热量会损坏裸光纤尖端。利用大鼠乳腺肿瘤模型，我们描述了一种在19号针套管插入肿瘤后将600微米光纤置于其中的方法。使用该装置，连续波Nd:YAG激光被输送至目标肿瘤，同时0.9%的生理盐水沿旁轴方向流入肿瘤。在5瓦功率下以500焦耳能量照射100秒，生理盐水流速为每分钟1毫升，同时将针-光纤从肿瘤中拔出10毫米，可诱导显著的凝固性坏死。在十次实验中，500焦耳能量照射后的平均传输损耗为2%。1.5毫升生理盐水引起的肿瘤水肿是短暂的。我们得出结论，采用上述技术，Nd:YAG激光能够以最小的传输损耗成功实现热凝坏死。
