As someone who worked in medical imaging many years ago, I need to be the pedant who says, “Well, actually, a CAT scan (or CT scan) fires x-rays through the body and measures what gets through, while an MRI uses a strong magnetic field to align the spins of all hydrogen atoms in the body, then sends a radio wave to disrupt those spins and measures the energy emitted as the atoms realign. They’re completely different technologies.”

But certain breeds of dogs can give lab results.

That’s why we also use positrons. So that all PET-scan.