Gregory K W, Prince M R, LaMuraglia G M, Flotte T J, Buckley L, Tobin J M, Ziskind A A, Caplin J, Anderson R R
Wellman Laboratory of Photomedicine, Massachusetts General Hospital, Boston 02114.
Lasers Surg Med. 1990;10(6):533-43. doi: 10.1002/lsm.1900100605.
Laser angioplasty systems with laser energy preferentially absorbed by atherosclerotic plaque may offer a safe method of plaque removal. This study evaluated the effect of blood upon selective energy absorption using a pulsed dye laser at 480 nm. Intra-arterial laser irradiation of normal rabbit femoral arteries demonstrated a perforation threshold energy with blood perfusion of 13.1 mJ per pulse compared to 87.9 mJ with saline (P less than .0001), indicating a deleterious effect in the presence of blood. An adverse effect upon arterial healing at 3 days was noted in sheep following intra-arterial irradiation during blood but not saline perfusion. Normal and atherosclerotic human aorta ablation thresholds differed significantly (P less than .0002) under saline (plaque: 20 mJ and normal: 120 mJ) but the difference under blood (plaque: 5 mJ and normal: 20 mJ) was not significant. We conclude that absorption of laser energy by blood can reduce the effect of differential absorption by endogenous chromophores in normal and pathologic vascular tissues and, therefore, removal of blood may be a prerequisite for selective ablation of atherosclerotic plaques.
激光能量优先被动脉粥样硬化斑块吸收的激光血管成形术系统，可能提供一种安全的斑块清除方法。本研究使用480nm的脉冲染料激光评估了血液对选择性能量吸收的影响。对正常兔股动脉进行动脉内激光照射显示，在血液灌注情况下，穿孔阈值能量为每脉冲13.1mJ，而在盐水灌注时为87.9mJ（P小于0.0001），表明在有血液存在时存在有害影响。在绵羊中，血液灌注而非盐水灌注期间进行动脉内照射后，在3天时观察到对动脉愈合有不良影响。在盐水中，正常和动脉粥样硬化的人主动脉消融阈值有显著差异（P小于0.0002）（斑块：20mJ，正常：120mJ），但在血液中（斑块：5mJ，正常：20mJ）差异不显著。我们得出结论，血液对激光能量的吸收会降低正常和病理血管组织中内源性发色团的差异吸收效果，因此，清除血液可能是选择性消融动脉粥样硬化斑块的先决条件。
