100WCO_2激光心肌血管再造术的实验研究

Experimental Study of Myocardial Revascularization by CO 2 Laser

本文给出了利用１００ＷＣＯ２激光心肌血管再造术动物实验研究结果。激光器采用１００ＷＣＯ２激光，经光关节臂传输和会聚，激光孔径０．２５～０．５ｍｍ，孔间距离５ｍｍ，照射时间０．３秒，利用附加“滤波器”激光打孔技术可减轻心脏的热损伤。结果表明，在正常心肌上打孔，孔周２７０μｍ以外的心肌基本上不受损伤；高功率密度的激光束心肌打孔能够改善心肌微循环，可以明显改善打孔区的心肌缺血程度。实验犬术后六个月铸型实验证实了激光孔道仍然存在。

Myocardial Revascularization By Laser is a kind of operation which uses laser beam to converge on the surface of myocardium and punches from epicardium to endocardium.Since 1987 in China the experiment has begun on animal with laser beam to punch in myocardium in order to improve myocardial microcirculation.Gassian beam of the law-order mode,which is output by CO 2 laser.CW CO 2 laser with power 100 W is modulated,which has changed from CW laser to quasi-CW laser.The technique of optical electronic modulation of laser beam is used to obtain short pulse width in output beam from CO 2 laser.The laser pules length can also be modulated from 0.ls,o.2s,……1s.Laser beam is transmitted with an Optical arm to make the laser beam deflect and focus.The distance between the holes was 5mm.The diameteres of the laser hole were 0.25-0.5mm.Irradiating time was 0.3sec.Making use of both the synchronous techique and the specical 'filtering',we can punch high quality fine and straight holes in the area of myocardial infarction with heart beating under room temperature condition.The laser beam can penetrate a thick myocardium wall nearly without heat damage in myocardium tissue.Ablative phenomenon is imperceptible to the naked eyes.The study shown that the myocardium beyond 270μm edges of the hole was normal. In this paper,experimental results of myocardial revascularization are given on living animals at the room temperature by 100 W CO 2 laser.The experimental results demonstrate that laser punching in myocardium can rebuild myocardial microcirculation.The casting mould experiment shows the laser hole still exists after dog's six month's poeration.The pathological cut sections for microscopic examination indicate clearly that laser holes are still kept going after three years of the dog's operation.