Imagine having a surgery with no knives involved. At TEDMED, Yoav Medan shares a technique that uses MRI to find trouble spots and focused ultrasound to treat such issues as brain lesions, uterine fibroids and several kinds of cancerous growths.img src="http://feeds.feedburner.com/~r/TEDTalks_video/~4/MOrFveRiJTo" height="1" width="1"/