Abstract
Injury associated with laser-induced tissue ablation may be reduced by using pulsed energy delivery at low repetition rates, as opposed to using continuous wave energy delivery. This study was designed to examine the similarities and differences between these two systems as regards the healing process, and to examine whether one is superior to the other. In order to test this postulate, the healing response of normal and atherosclerotic aorta were examined after exposure in vivo to argon and excimer (XeCl 308 nm) laser radiation in hypercholesterolemic swine. Swine were fed hyperlipidemic diets for eight months following balloon denudation of the descending aorta. Following general anaesthetic, the descending aorta was isolated and laser burns were made on both normal and atherosclerotic intima using a continuous wave argon laser delivered through a 50Μ diameter quartz fibre, and a XeCl excimer laser carried through a 1 mm diameter fibre. Energy levels of 3 to 5 J were applied with the argon laser. The pulse duration for the excimer laser was 30 ns and craters were produced using 10 to 60 pulses at a repetition rate of 20 Hz and an energy density of 2 J cm−2.
Forty-eight hours after laser application, craters created by both lasers were filled with thrombus material. Argon burns were surrounded by thermal and acoustic injury which was not seen with excimer burns. Three weeks after laser application all crater surfaces were reconstituted. Unlike the excimer burns, argon craters demonstrated necrosis well beyond the crater margins and were characterized by multinucleate giant-cell reaction surrounding char debris. By nine weeks both excimer and argon laser burns were covered by fibrous tissue but could be distinguished by the fact that char debris and subjacent tissue injury arose with the argon burns.
The results suggest that both lasers can be used to remove focal atherosclerotic plaque from arteries without inducing excessive thrombogenicity. Rapid healing is observed with both; however, damage to surrounding tissue is significantly greater with a continuous energy delivery laser as opposed to pulsed energy delivery.
Similar content being viewed by others
References
Choy DSJ, Stertzer S, Rotterdam JZ, Bruno MS. Laser Coronary angioplasty: experience with 9 cadaver hearts.Am J Cardiol 1982,50:1209–12
Abela GS, Norman S, Feldman RL et al. A new model for evaluation of transluminal recanalizations: human atherosclerotic coronary artery heterografts.Am J Cardiol 1984,54:200–5
Abela GS, Norman SJ, Cohen DM et al. Laser recanalization of occluded atherosclerotic arteries in vivo and in vitro.Circulation 1985,71:403–11
Abela GS, Normann S, Cohen D et al. Effects of carbon dioxide, Nd:YAG, and Argon laser radiation on coronary atheromatous plaques.Am J Cardiol 1982,50:1199–1205
Lee G, Ikeda R, Herman I et al. The qualitative effects of laser irradiation on human arteriosclerotic disease.Am Heart J 1983,105:885–9
Farrell EM, Higginson LA, Nip WS et al. Pulsed excimer laser angioplasty of human cadaveric arteries.J Vasc Surg 1986,3:284–7
Gerrity RG, Loop FD, Golding LAR et al. Arterial response to laser operation for removal of atherosclerotic plaques.J Thorac Cardiovasc Surg 1983,85:409–21
Deckelbaum LI, Isner JM, Donaldson RF et al. Reduction of laser-induced pathologic tissue injury using pulsed energy delivery.Am J Cardiol 1985,56:662–7
Hayes JR, Wolbarsht ML. A thermal model for retinal damage induced by pulsed lasers.Aerospace Med 1968,39:474–80
Welch AJ. The thermal response of laser irradiated tissue.IEEE J Quantum Elect 1984,12:1471–81
Anderson RR, Parrish JA. Selective photothermolysis: precise microsurgery by selective absorption of pulsed radiation.Science 1983,220:524–7
Lee G, Ikeda RM, Theis JA et al. Acute and chronic complications of laser angioplasty: Vascular wall damage and formation of aneurysm in the atherosclerotic rabbit.Am J Cardiol 1984,53:290–3
Abela GS, Crea F, Seeger JM et al. The healing process in normal canine arteries and in atherosclerotic monkey arteries after transluminal laser irradiation.Am J Cardiol 1985,56:983–8
Gorog P, Shafi S. Increased accumulation of lipoprotein and cholesterol in re-endothelialized rat carotid artery after laser damage.Atherosclerosis 1985,57:33–42
Prevosti LG, Lawrence JB, Leon MB et al. Surface thrombogenicity after excimer laser and hot-tip thermal ablation of plaque: morphometric studies using an anular perfusion chamber.Surgical Forum 1987 (Vascular Problems):330–3
Author information
Authors and Affiliations
Additional information
Work supported in part by: Heart and Stroke Foundation of Ontario, Grant-in-Aid No. 5-17
Rights and permissions
About this article
Cite this article
Higginson, L.A.J., Farrell, E.M., Walley, V.M. et al. Arterial response to excimer and argon laser irradiation in the atherosclerotic swine. Laser Med Sci 4, 85–92 (1989). https://doi.org/10.1007/BF02032603
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02032603