Vincent G M, Mackie R W, Orme E, Fox J, Johnson M
University of Utah Medical Center, Department of Internal Medicine, Salt Lake City.
J Clin Laser Med Surg. 1990 Jun;8(3):59-61. doi: 10.1089/clm.1990.8.59.
Photosensitization of atherosclerotic (Ath) plaque with exogenous chromophores may confine laser irradiation (LI) injury to Ath plaque and allow safer and more efficacious laser angioplasty. Dihematoporphyrin ether (DHE) accumulates preferentially in plaque, and previous in vitro LI studies have shown confinement of LI injury to plaque. To further evaluate DHE enhanced laser angioplasty, 5 Ath Yucatan miniswine with 8 iliofemoral stenoses (Sten) were treated with 2.5 mg/kg of DHE IV. Twenty-four hours later, 632 nm continuous wave LI was delivered to Sten using 200mu core optical fiber with a 582mu x 1cm diffusing tip. Angiograms were performed before, immediately after, and two weeks following LI. 6 of 8 vessels showed improvement. Control mean Sten was 71%, immediate post LI was 55% and 2 weeks post LI was 19% Sten. In 4 of 6 responding vessels, there was 0% Sten at 2 weeks post LI and the previously stenotic segments appeared normal. 2 of 6 responders showed only modest improvement, from control mean Sten of 83% to 55% Sten at 2 weeks. 2 of 8 vessels showed no improvement. There were no perforations or dissections. The excellent results in some vessels demonstrate the potential of photosensitizer enhanced LI as very effective primary therapy of Ath. The time course of improvement indicates that both immediate thermal and delayed photochemical (photodynamic therapy) effects are operative. Further studies are required to identify reasons for failure in some vessels.
用外源性发色团对动脉粥样硬化（Ath）斑块进行光致敏，可能会将激光照射（LI）损伤局限于Ath斑块，从而实现更安全、更有效的激光血管成形术。双血卟啉醚（DHE）优先在斑块中蓄积，之前的体外LI研究已表明LI损伤局限于斑块。为了进一步评估DHE增强型激光血管成形术，对5只患有8处髂股狭窄（Sten）的尤卡坦小型猪静脉注射2.5mg/kg的DHE进行治疗。24小时后，使用带有582μm×1cm扩散头的200μm芯光纤对狭窄部位进行632nm连续波LI照射。在LI照射前、照射后即刻以及照射后两周进行血管造影。8条血管中有6条显示改善。对照时平均狭窄率为71%，LI照射后即刻为55%，LI照射后两周为19%。在6条有反应的血管中，有4条在LI照射后两周时狭窄率为0%，先前狭窄的节段看起来正常。6条有反应的血管中有2条仅显示中等程度的改善，对照时平均狭窄率为83%，两周时为55%。8条血管中有2条没有改善。没有出现穿孔或夹层。一些血管的出色结果表明，光敏剂增强LI作为Ath非常有效的主要治疗方法具有潜力。改善的时间进程表明即时热效应和延迟光化学效应（光动力疗法）都在起作用。需要进一步研究以确定一些血管治疗失败的原因。
