What is the fine-grained topic of the following text: "The navigational ability of the VisiGlide 2 exceeds any wire that I've used previously,” said Dr. David Diehl, Director of Interventional Endoscopy, Geisinger Medical Center, Danville, PA. “The tip can negotiate difficult strictures, and with its one-to-one torque control, I can directly steer the wire exactly where I want it to go." Only return the topic.
Navigational ability of the VisiGlide 2 wire in Interventional Endoscopy