Recently the Army also began fielding some of the world’s most advanced new CT technology at Brooke Army Medical Center (Fort Sam Houston, Texas) and General Leonard Wood Army Community Hospital (Fort Leonard Wood, Missouri).
“Those CTs can image the heart in one rotation,” Moaveni stated. “That means the X-ray machine doesn’t have to stay on for a long amount of time to overexpose the patient.”
Along with these representative technology efforts, USAMMA representatives are also involved in a range of supporting imagery projects.
Said another way, the new CT systems are able to produce a 3-D image of the entire heart in less than one heartbeat. The new design uses a wider detector that allows the system to capture complete images of organs, such as the heart, in one scan rather than multiple scans that have to be “stitched together” electronically.
“Dose reduction consists of three parts,” Moaveni summarized. “The first is the software algorithms that control how the data is captured from the detectors and processed. Second, it has the capability of communicating with the hardware in the X-ray, including the generator’s release of the voltage. The third part is timing. We have found out that the wider the detector, the less dose to the patient. So the advancements in CT dose reduction since 2006 have been tremendous.”
Magnetic Resonance Imaging
Another critical imaging technology is magnetic resonance imaging (MRI). Although not used for trauma cases, MRI is an exceptional tool for soft tissue diagnostics. Moaveni said that recent MRI advances have focused on increases in the magnet coil strength.
“We have magnets that have field strengths up to 15 tesla and we have magnets with field strength of .2 tesla,” he began. “But the standard today is a 1.5 tesla MRI. However, while the 1.5 tesla MRI could be adequate for imaging the abdomen, the liver, the lungs, muscles, joints, and cartilage, it takes time for imaging neurons, for the brain, to a point where radiologists can see the minute connections between the different centers of the brain.
“They found out that when they doubled the strength of the magnet – to go from 1.5 to 3 tesla – the speed of the images improved. Previously a patient had to stay in a 1.5 tesla MRI for 45 minutes to get their liver imaged and they had to stay for about two hours to get the neurons imaged in their head. But with the 3 tesla MRI, this time was decreased,” he said.
“So that’s what’s behind the increase of field strength from 1.5 to 3 tesla,” he added. “However, as I said, we have magnets that operate on .2, which can image a liver in about three hours. And we have magnets that are 15 tesla, but it’s usually used for research. It’s very targeted – in case they want to see a certain part of the anatomy. But it’s not good for routine imaging.”
Digital Breast Imaging
While changing military demographics might lead some to expect an increased need for breast imaging, Moaveni said that the actual number of breast imaging locations has remained fairly constant. However, he quickly added that the recent introduction of new digital breast imaging technologies has expanded patient opportunities by decreasing the time required for imaging.