Multimodality imaging uncovers ‘landmarks’ for peripheral arterial disease recovery

Doctors often struggle to pinpoint the best treatment for patients with peripheral artery disease, or to determine whether or not they are improving. But with a new study, a team from the University of Illinois at Urbana-Champaign has narrowed that clinical gap.

The research, published in Theranostics, combined multiple different imaging modalities to reveal major PAD recovery “landmarks.” These checkpoints, as it were, can help clinicians compare an individual’s health status to key rehabilitation milestones. While their study has only been performed in mice thus far, they believe it can be easily replicated in humans with impactful results.

“We are very interested in improving diagnosis and treatment,” postdoctoral researcher and first author of the study Jamila Hedhli said in a university news item. “Many people are working to develop early diagnosis and treatment options for patients. Having standard landmarks for researchers to refer to can facilitate all of these findings, move them forward to clinic and, we hope, result in successful clinical trials.”

Peripheral artery disease occurs when arteries in the limbs—commonly the legs—begin to narrow and restrict blood flow. It’s typically diagnosed after a patient reports difficulty walking; by that time, the disease is already far advanced. And even then, there is no current standard of treatment for the affliction that impacts 27 million across Europe and North America.

Hedhli and colleague used a combination of high-sensitivity ultrasonic power Doppler, laser speckle contrast, photoacoustic imaging and PET scanning to establish a comprehensive picture of biological changes during four stages of PAD recovery. They identified a number of changes in muscle tissue, blood vessels and gene expression in mice with narrowed leg arteries, which were used to emulate PAD in humans.

“Each imaging method gives us a different aspect of the recovery of PAD that the other tools will not. So instead of looking at only one thing, now we’re looking at a whole spectrum of the recovery,” Hedhli said. “By looking at these landmarks, we’re allowing scientists to use them as a tool to say, ‘at this point, I should see this happening, and if we add this kind of therapy, there should be an enhancement in recovery.’”

Next up, they plan to map their PAD landmarks in larger mammals, before eventually moving on to human patients. The National Institutes of Health, the American Heart Association, and the Ministry of Science and Higher Education of Poland supported their work.