I have the episode recorded so I watched that scene and transcribed for you what was said. Hope that helps.
DEREK: Issac, if I get in there and it looks too dangerous to remove, the responsible thing is to close you back up.
ISSAC: Don't close me back up. If it's too complicated, cut the cord. Paralyze me if you must. I survived a war, did you know that?
DEREK: No.
ISSAC: I survived a war where they put bodies in mass graves where there was once a playground. I survived the death of my family, my parents, my brothers and sisters. Then I survived the death of my wife and child when they starved to death in a refuge camp. I survived the loss of my country. Of hearing my mother tongue spoken. Of knowing what it feels like to have a place to call home. I survived. And I will survive the loss of my legs. If I have to, I will survive it. Okay? But Derek...
DEREK: Yes?
ISSAC: There is always a way. When things look like there's no way, there is a way. To do the impossible. To survive the unsurvivable. There's always a way. And you? You and I have this in common. We're inspired. To face the impossible, we're inspired.
So if I can offer one piece of advice to the world's foremost neurosurgeon. Today, if you become frightened, instead, become inspired.