Laser recanalization: a basic and clinical perspective.

Abstract

Inspite of the effectiveness of PTCA and surgery in the treatment of occlusive vascular diseases, still a number of patients remain untreatable by these methods. Laser light with its ability to ablate tissue and to be delivered even in small distal branches of the vascular tree seemed to offer a new perspective. The interaction between laser light and tissue is determined by special physical characteristics. Up till now none of the available laser systems are optimal for application in the cardiovascular system, but still many of them have been effective clinically. One common complication was the high perforation rate by the use of flexible quarz fibers which could not be visualized by fluoroscopy. The addition of a small metal ring and later-on of a metal cap covering the end of the fiber showed significant improvements. Not only could those fibers be visualized by a fluoroscopy, but could convert laser energy into thermal energy. The perforation rate was decreased and a greater size channel created. Lately the introduction of a small saphir window at the tip of the metal cap offered the combined application of light and thermal energy. Animal studies demonstrated these advantages with a low perforation and a high penetration rate of atherosclerotic material. Clinical studies also revealed good results and a significantly lower perforation rate with the metal capped probe. Using the probe with a small saphir window at its tip, the success rate in totally occluded peripheral vessels, not treatable by conventional PTCA, was 82%. As the newly created channel showed a sufficient diameter.(ABSTRACT TRUNCATED AT 250 WORDS)