Thoracoscopic Treatment for Pulmonary Blebs using Carbon Monoxide Laser and Infrared Glass Fiber

Abstract

We adopted Carbon Monoxide(CO) laser for thoracoscopic treatment of pulmonary blebs. CO laser (wavelength; 5.4μm) could be delivered by chalcogenide glass(As-S) fiber. A CO laser fiber cable for endoscopic laser therapy was successfully developed. This laser cable contained a As-S infrared fiber covered with a teflon sheath, ZnSe optical window and thermocouple installed at the side of fiber tip. The absorption coefficient of CO laser (10²cm^-1) was equivalent to the thickness of the bleb wall(0.06-0.5mm). The sterilized flexible bronchoscope was inserted through the thoracoscopic outer sheath under local anesthesia. Laser power at the tip was 2-3W and irradiation duration was O.5sec each. Shrinkage of blebs was obtained by non-contact method of CO laser irradiation without perforation of the bleb. The temperature change caused by particle adhesion was easily detected to avoid damage to the fiber tip. Our new technique was found to be safe and effective for less invasive treatment of pulmonary blebs.