The development of a composite-type optical fiberscope system for fetoscopic laser photocoagulation of chorionic plate anastomosing vessels (FLPC).

We developed a new laser device using a composite-type optical fiberscope for laser surgery to treat twin-twin transfusion syndrome. The composite-type optical fiberscope (2.2 mm in external diameter) consists of a centrally located single fiber for laser treatment (0.1 mm in diameter) and its surrounding fibers for diagnosis. This fiberscope enables transmission of 40-W Yb fiber laser. The Yb fiber laser can be focused to 10mm focal length using two lenses on the tip of the fiberscope. In this research, we emitted the laser to in vivo porcine mesenteric vessel with blood flow both with an established laser fiber of 0.6-mm diameter (0.6-mm normal fiber) and with our composite-type optical fiberscope to compare the cautery performance of those devices. According to the experimental results, the composite-type optical fiberscope has a cautery efficiency equal to that of a 0.6-mm normal fiber, and it can contract the vein diameter about 35% as compared to the vein diameter before laser irradiation.