レーザーアテレクトミーの基礎的研究—側溝付メタリックチップを使用したレーザー照射の血管壁蒸散効果について

A Fundamental Study of Laser Angioplasty:Vaporizing effect of laser irradiation on the arterial wall using a side hole metallic tip

　閉塞性動脈硬化症の治療法に経皮的レーザー血管形成術があるが，アテローマや血栓などが偏心性に存在するときにはしばしばレーザー照射が困難なことがある．われわれはこの問題を側溝付きメタリックチップを使う照射で改善を図る目的でレーザーによる動脈壁蒸散効果の基礎的検討を行った．レーザー照射エネルギーが増加すると動脈壁の蒸散効果は高まるが，ベアファイバーによるレーザー照射と比較するとその効果は1／3〜1／2程度であった．側溝付チップとレーザーファイバー先端の距離を短縮すればより効果的となることが明らかとなった．

Percutaneous transluminal laser angioplasty is a method to treat arteriosclerotic obstruction. It is difficult to irradiate laser to an eccentric arteriosclerotic lesion. Therefore, we tried to improve the vaporizing effect of laser irradiation by using a side hole metallic tip. Two types of side hole metallic tip were exper-imented with. The results showed that, the size of the tissue defects increased as laser energy increased. How-ever, the vaporizing effect of a side hole metallic tip was weaker than that by a bare laser fiber. The difference of vaporizing effect between these two kinds of laser probes seems to be due to the fact that a side hole metallic tip has a wider gap space between the fiber core and the side hole metallic tip. Once this problem is solved, the side hole metallic tip should become a very useful tip to treat an eccentric atheromatous plaque and prevent lateral damage and perforation of the lateral wall.