Narrator: This is Science Today. There are two crucial elements to successful brain tumor surgery - the removal of the tumor and causing no harm to critical areas of the brain. Dr. Neil Martin, chief of the UCLA Neurosurgery Division, says in the past, it was difficult for surgeons to visually see the margin of the tumor.

Martin: We now have an operating room with an MRI scanner in it. So we remove the tumor, simply pivot the patient, get a scan and if there's anything left we take it out immediately. It's really made a major difference in the success of removing tumors of this sort.

Narrator: To ensure no damage is done, patients can even be operating on while awake.

Martin: Surprisingly, you can numb the pain sensitive structures in the scalp and the head and operate on the brain without the patient experiencing any discomfort and that allows us to test them, to ask them to speak, to read, identify objects while we're actually working to make sure that those critical language functions are preserved and that none of those are injured as the tumor's removed.

Narrator: For Science Today, I'm Larissa Branin.