Modern radiation therapy uses computer-controlled multileaf collimators to shape the radiation beam automatically.

“instead of having lead blocks that you're sliding into the path of the beam now everything is shaped in the head of the beam by our computer so you hit a button and when I've already programmed the the the uh treatment pro the treatment planning values the machine knows how to shape the beam to match the aperture of whatever you're trying to do so that's all fully automatic now”