The role of shock waves in pulsed-dye laser angioplasty

Fr~~m 2nd l)ep.~rtmt~~t (11 Internal Medicine, Faculty of Medicine, Unitersiry of T~rkyo. .Ind F,xplorations Fonctionnelles and Department of Pathology, IJnivrrsity Hospital Henri Mundw, University uf Paris XII. Reprint requwts: ‘I’akanohu Tomaru. MD, 2nd Department of Internal Medicine, Faculty of Medicine. ITniversity of Tokyo. 7-3-l Hongo, Bunkyoku. ‘I’oky,,, Japan. 4/4/?9435 acteristics relevant to the shock waves have not been well elucidated. Although pulsed lasers are being used for laser angioplasty,“-” the efficacy and advantage of t.he multifiber catheter for pulse laser angioplasty has not been well understood. In this study, we investigated the ablation characteristics of this laser with respect to the shock waves. influence of t,he medium and guide wire on shock waves, and efficacy of the multifier catheter for laser angioplasty. Methods. A flash-lamp excited pulsed-dye laser at a wavelength of 480 nm, 2.1 psec pulse duration and 10 Hz was used. Laser energy was delivered through a 200 urn optical fiber or a 1.5 mm multifiber catheter that consisted of 14 optical fibers of 150 wrn circumferential diameter arranged around a central lumen in which an 0.014.inch guide wire was inserted. Lasing was done at 100 mjoules/ pulse by the multifibercatheter or at 40 nrJoules/pulse by the single fiber. Laser irradiation was done m a 10 cm’! syringe system that was connected to a strain ::auge pressure