When you delete a photo on a smartphone, it usually isn't immediately wiped from the hardware. Instead:
| Modality | Best for... | Uses Radiation? | Time | | :--- | :--- | :--- | :--- | | | Absolute blood flow & oxygen metabolism | Yes (low dose) | 10-20 min | | MRI | Soft tissue anatomy | No | 30-60 min | | CT | Bone & bleeding | High dose | 5 min | | FDG-PET | Glucose metabolism (Cancer staging) | Yes | 60-90 min | ox imágenes