case presentation we present a case of a grade iii coronary perforation in which the double guiding catheter technique helped us to deliver the graft stent. conclusions the double-guiding technique is useful in emergency situations to increase the safety and efficacy of sealing a coronary perforation. introduction coronary vessel perforation is one of the most feared complications of coronary a...

waveguides with low confinement loss, low chromatic dispersion, and low nonlinear effects are used in optical communication systems. optical fibers can also be employed in such systems. besides optical fibers, photonic crystal fibers are also highly suitable transmission media for optical communication systems. in this paper, we introduce two new designs of index-guiding photonic crystal fiber ...