Let’s Zoom In

A 3T MRI machine; (inset) Dr. Matthew Brady.

Meet the 3T MRI: one of the most powerful and precise diagnostic imaging tools available 

Written By Kinsey Gidick 

In 1895, a Bavarian physics professor (accidentally!) invented the X-ray. It didn’t take long for his happenstance discovery to be put to use by doctors around the globe to take a peek inside the human body, which previously had only been accessible via scalpel. The field of diagnostic imaging—or using noninvasive imaging tools to see inside the body in order to diagnose injury or disease—took off from there. CT scans hit the scene in 1971 and the first magnetic resonance imaging (MRI) exam was performed in 1977, with machines getting better, safer and more precise ever since.

The 3T MRI, which the Roper St. Francis Healthcare radiology department will begin using in February 2021, is one of the newest and strongest imaging machines available. “The 3T MRI yields clearer images of certain areas of the body than other machines,” says Dr. Matthew Brady, chair of the Roper St. Francis Healthcare radiology department. “It can also provide a shorter, more comfortable experience for the patient than past MRI models.” Here,
Dr. Brady shares more on this groundbreaking machine. 

HOUSE CALLS (HC): How does MRI work and when is it used?
MRI is an imaging technique that uses radio waves and a magnetic field to see inside the body. The patient lies inside a tubular machine while radio waves and a powerful magnet work together to produce detailed images of internal organs and tissues.

The other two most common diagnostic imaging techniques—X-rays, which use radiation, and CT scans, which use powerful X-rays—provide big-picture images of the skeletal structure, organs and tissues. MRIs yield more detailed imagery that is especially helpful for analyzing soft tissues, ligaments and organs.

HC: How does 3T MRI differ from past models?
Put simply, 3T MRI machines use a stronger magnet. Traditional MRI scanners operate at 1.5T, or Teslas, while the 3T MRI operates at twice that. The 3T also has a shorter and wider magnetic bore—the donut you lie in—than past models.

HC: What are the benefits of these changes?
First off, the MRI process is more comfortable for patients. Because the machine is more powerful, the exam can take a shorter amount of time than a traditional MRI. That, along with the wider, shorter bore, is helpful for people who may have felt claustrophobic during traditional MRI exams.

Diagnostically, the 3T MRI can provide more detailed images of certain organs and soft tissues than other machines. This level of detail can be particularly helpful for prostate imaging as well as imaging of intricate parts of the musculoskeletal system such as wrists, fingers and toes.

HC: Can you give an example of when using the 3T MRI might be helpful?
Absolutely. Let’s consider prostate cancer. For men who are diagnosed with low-grade prostate cancer—meaning it’s localized and has a low risk for progression—the urologist and oncologist may determine that “active surveillance,” or closely monitoring the tumor for growth, is the best course of treatment. The increased precision of the 3T MRI gives a clearer look at the tumor, which can be useful in monitoring the disease’s progression.

The 3T MRI is one of many imaging tools we have to monitor and diagnose disease. In some cases, a traditional 1.5T MRI is the best imaging option; in others, the increased precision of the 3T MRI can be helpful. We look at each patient’s case individually to determine the best imaging tool for the job.