What can a mri detect compared to an ultrasound or x-ray?

MRI gives more detailed images of internal structures than X-ray, ultrasound, and (usually() CT scan. For some conditions, it is much more sensitive, i.e. better detection of small and subtle abnormalities and changes. There is almost never a good reason to decline MRI if your doctor advises it. The main problem for some people is discomfort being inside small spaces, especially if claustrophobic