3-D technology is making its way from the movies, into the operating room. How is this technology enhancing brain surgeries? Dr. John Y.K. Lee, medical director of the Penn Gamma Knife Center and assistant professor of neurosurgery at Penn Medicine, describes the advantages of using 3-D technology for removing various types of ventral skull-based tumors, and says the stereoscopic views provided by a 3-D endoscope help neurosurgeons preserve critical areas of the brain. Will 3-D endoscopes replace their 2-D predecessors? Dr. Lee Freedman hosts.