Since the CT scanner emits radiation, why isn’t MRI technology used to determine one’s calcium score?

After all, there is zero emission of radiation from an MRI procedure.

Furthermore, many people would much prefer lying inside the famed MRI “tube” than being exposed to the radiation from a CT scan.

The CT scan is what’s used for measuring the calcium score.

Magnetic resonance imaging is known to be more sensitive than CT scan for the detection of certain conditions.

MRI is a highly sensitive procedure, able to pick up or discern certain findings with more sensitivity than will an ultrasound or mammogram.

An example is an MRI detecting a malignant breast tumor that was “missed” on an ultrasound as well as mammogram.

But calcium scoring is a whole new animal.

“MRI cannot be used for calcium screening because MRI is relatively insensitive for detection of calcification,” says Resham Mendi, MD, a renowned expert in the field of medical imaging, and the medical director of Bright Light Medical Imaging.

Dr. Mendi adds, “CT is far more sensitive. MRI would be an ineffective test to look for calcific plaque in the coronary arteries.”

This will come as a surprise to anyone who knows that magnetic resonance imaging provides a very high degree of sensitivity.

Nevertheless, this high sensitivity does not apply to calcified plaque inside coronary arteries.

CT Scan Is Your Only Option

So if you want to find out what your calcium score is, you’ll have to undergo a CT scan. The procedure takes about 15 minutes.

A woman who is pregnant or trying to conceive should not undergo a coronary calcium scan.

A person at low risk for coronary artery disease is not a candidate for a calcium scoring, even though many healthy, low risk individuals are getting CACs due to increased awareness.

If you’re healthy, fit and at low risk for coronary heart disease, you should discuss the practicality of calcium scoring with a cardiologist.

dr. mendi
Dr. Mendi has published several articles in radiology journals and has expertise in MRI, women’s imaging, musculoskeletal, neurological and body imaging.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer. 
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