You mentioned that, MRIs are almost always preferable to CTs for imaging the head, and usually for the spine, except during trauma or when MRIs are not practical – such as when there are metal clips on the head. Why is the MRI not practical when there are metal clips in the head? Kindly explain.

Dr. Greene’s Answer:

The MRI is a very strong magnet — you would not want it to move around metal clips in the head, or anywhere else in the body!

Read More From This Series:
CT Scan Defined
CT Scan, Ultrasound or MRI?
CT Scan Safety
CT Scans and Radiation Exposure
CT Scan Risks
Higher Risks in Children
Who Should Receive a CT Scan?
X-Ray or a CT Scan?
Alternatives to a CT Scan
When Should a CT Scan be Performed?
Important Tip to Reduce to Radiation
Questions to Ask before Every CT Scan
Other Radiation Exposures
Measures That Radiologists Should Adhere to When Administering a CT Scan
CT Scans and Cancer
When are MRIs not Practical?
What is Ionizing Radiation? Who are Radiologists?

Reviewed By:
February 14, 2008

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