The world’s first ever full-body medical scanner will make its public debut in Sacramento this Spring 2019. This machine they are calling EXPLORER has been a decade-long project for UC Davis scientists Simon Cherry and Ramsey Badawi. After so many years of hard work, they have finally produced their first human photos and video. The images revealed were even more incredible than they had ever imagined they would be.
“While I had imagined what the images would look like for years, nothing prepared me for the incredible detail we could see on that first scan,” said Cherry, distinguished professor in the UC Davis Department of Biomedical Engineering.
Badawi and Cherry first conceptualized the scanner 13 years ago. A few years later, in 2011, they received a $1.5 million grant from the National Cancer Institute. The money they acquired allowed them to establish a wide-ranging consortium of researchers and other collaborators. After a few more years working with their new team, they received another grant (in 2015) worth $15.5 million from the NIH. The funding this time allowed them to team up with a commercial partner and get the first EXPLORER scanner built.
Their commercial partner is Shanghai-based United Imaging Healthcare (UIH). UIH built the system for the scanner based on their latest technology platform and will eventually manufacture the devices for the broader healthcare market. The machine is a combined positron emission tomography (PET) and x-ray computed tomography (CT) scanner that can image the entire body at the same time.
Badawi, chief of Nuclear Medicine at UC Davis Health and vice-chair for research in the Department of Radiology, said he was dumbfounded when he saw the first images, which were acquired in collaboration with UIH and the Department of Nuclear Medicine at the Zhongshan Hospital in Shanghai.
“The level of detail was astonishing, especially once we got the reconstruction method a bit more optimized,” he said. “We could see features that you just don’t see on regular PET scans. And the dynamic sequence showing the radiotracer moving around the body in three dimensions over time was, frankly, mind-blowing. There is no other device that can obtain data like this in humans, so this is truly novel.”
EXPLORER produces higher-quality diagnostic PET scans than have ever been possible. It can produce an image in as little as one second because it is able to capture radiation far more efficiently than other scanners. Therefore, it can scan up to 40 times faster than current PET scans and can produce a diagnostic scan of the whole body in as little as 20-30 seconds.
EXPLORER scans with a radiation dose up to 40 times less than a current PET scan, opening new avenues of research and making it feasible to conduct many repeated studies in an individual, or dramatically reduce the dose in pediatric studies, where controlling cumulative radiation dose is particularly important.
“The tradeoff between image quality, acquisition time and injected radiation dose will vary for different applications, but in all cases, we can scan better, faster or with less radiation dose, or some combination of these,” Cherry said.
The most exciting feature of this machine is that it will be able to evaluate what is happening in all the organs and tissues of the body simultaneously. Its ability to capture entire body images in a single momentary scan means that clinicians can measure the effects of something moving across the entire body in real-time. For example, video footage can capture medicine as it travels through a person’s bloodstream.
This amazing device and it’s groundbreaking results will be shown at the upcoming Radiological Society of North America meeting beginning Nov. 24th in Chicago. The developers of EXPLORER believe this technology will be a major improvement for diagnostics and tracking of disease (such as cancer) progression; as well as a for researching new drug therapies. Cherry is optimistic it shouldn’t be too long before it is available to hospitals and research bodies worldwide.