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" Why does my doctor want a MRI?"

ZocdocAnswers Why does my doctor want a MRI?


I had a ct scan and my doctor said it showed spots on my spleen and lungs and now wants a mri. What is my doctor looking for?


Sorry to hear about your concerns, and hope that all is well. It's quite difficult to say exactly what your doctor may be looking for by ordering further imaging, but I would hope that you discuss this with him or her. In general, a CT is better at providing detail of the bones and is a much simpler scan to obtain. The idea of a CT is based on serial x-rays that can be stacked together to provide a picture of what is going on on the inside. While contrast can be added to give a picture of the blood vessels and some other soft tissue information, MRI is much better at characterizing things that are soft, like nerves, organs, etc. Many doctors will order imaging studies in that order, using a CT to screen for a problem, and an MRI to further characterize what may be going on if needed. MRIs use powerful magnets to align some of the molecules in your body, and as these molecules go back to their original orientation they emit energy that can be organized by a computer to detail what is happening. An MRI takes more time and costs more. Please speak with your doctor for the details of why he or she wants the scan.

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