Schwengel R H, Gregory K W, Hearne S E, Scott H J, Beauman G J, Mergner W J, Caplin J L, Ziskind A A
Division of Cardiology, University of Maryland School of Medicine, Baltimore, Maryland 21201.
Lasers Surg Med. 1993;13(3):284-95. doi: 10.1002/lsm.1900130305.
Vasoconstriction is a clinical problem associated with invasive vascular procedures, microvascular reconstruction and subarachnoid hemorrhage. We sought to characterize the ability of pulsed-dye laser irradiation to reverse and prevent vasoconstriction in an anesthetized rabbit model of surgically and pharmacologically induced vasoconstriction. Five groups of experiments were performed to study the effect of pulsed-dye laser irradiation delivered through a 320 microns core ball-tip fiber into the femoral artery. The studies demonstrated that pulsed-dye irradiation can reproducibly cause vascular dilatation. The zone of vasodilatation propagated equally proximal and distal to the site of irradiation within the vessel. When saline was infused into the vessel to replace flowing blood during delivery of laser irradiation, no significant vasodilatation occurred. After laser irradiation reversed surgical and pharmacologic vasoconstriction, the vessel was resistant to further pharmacologic vasoconstriction. This resistance to pharmacologic vasoconstriction did not occur if the vessel was pharmacologically predilated before delivery of laser irradiation. Pathologic analysis of the vessels revealed endothelial damage and mild to moderate medial necrosis, most significant at the site of energy delivery. These studies provide characterization of pulsed-dye laser-mediated vasodilatation in an in vivo model. Delivery of pulsed-dye laser energy has potential clinical application and warrants further investigation.
血管收缩是与侵入性血管手术、微血管重建和蛛网膜下腔出血相关的临床问题。我们试图在手术和药物诱导血管收缩的麻醉兔模型中，表征脉冲染料激光照射逆转和预防血管收缩的能力。进行了五组实验，以研究通过320微米芯球头光纤向股动脉输送脉冲染料激光照射的效果。研究表明，脉冲染料照射可重复性地引起血管扩张。血管扩张区域在血管内照射部位的近端和远端同等程度地扩展。在激光照射期间向血管内注入生理盐水以替代流动血液时，未发生明显的血管扩张。在激光照射逆转手术和药物性血管收缩后，血管对进一步的药物性血管收缩具有抗性。如果在激光照射前对血管进行药物预扩张，则不会出现这种对药物性血管收缩的抗性。对血管的病理分析显示内皮损伤和轻度至中度中层坏死，在能量输送部位最为明显。这些研究提供了体内模型中脉冲染料激光介导的血管扩张的特征。脉冲染料激光能量的输送具有潜在的临床应用价值，值得进一步研究。
