Can I have an MRI and CT scan after bypass surgery because of other illnesses? Will it cause any harm to my body? Will it affect the test results? Many discharged patients who need MRI and CT examinations for other illnesses ask if they can have them done. Are they worried that the wires and temporary pacemaker leads in their bodies will cause harm to their bodies? Will they affect the test results? Please rest assured that if you need to do these tests, you can do them, and the effects on the body (especially nuclear magnetic, there will be some thermal effects) will not cause substantial harm to the body. There are some artifacts on the quality of the imaging, but experienced physicians will not affect the diagnostic results.