Noninvasive Skin Scan Could Reveal Early Microvascular Damage Linked to Heart Disease

Researchers at Helmholtz Munich and the Technical University of Munich (TUM) have built an imaging device called fast-RSOM that looks at the body's smallest blood vessels through the skin, with no needles, incisions, or other invasive steps. The work was published in the journal Light: Science & Applications.

The target is an early and hard-to-see problem. One of the first warning signs of cardiovascular disease appears deep in the tiniest vessels, where their ability to expand and contract begins to falter. The condition is called microvascular endothelial dysfunction, or MiVED. Until now, according to the team, doctors had no precise, noninvasive way to see or measure these changes in people.

Fast-RSOM is meant to fill that gap. Dr. Hailong He, a researcher at the Institute of Biological and Medical Imaging at Helmholtz Munich and TUM and the study's first author, says the device makes it possible for the first time to assess endothelial dysfunction noninvasively in humans, at the resolution of single capillaries and individual skin layers. Dr. Angelos Karlas, co-first author, a vascular surgeon and senior research scientist at TUM University Hospital, describes the result as an unprecedented view of how cardiovascular disease shows up at the microvascular level.

The technology produces dynamic, high-resolution MiVED biomarkers. These describe subtle impairments in vessel function that, the researchers say, are generally present before clinical symptoms or measurable macroscopic signs of disease appear. Such changes are often linked to risk factors like smoking, high blood pressure, and obesity. Standard risk assessment works from those descriptive conditions. Fast-RSOM, by contrast, is designed to measure the actual changes those conditions have caused in the microvascular system, long before major complications develop.

The team suggests this could allow earlier detection and prevention, and more precise monitoring of cardiovascular health. It could help identify people at higher risk of cardiovascular events with greater precision, and it could be used to track whether lifestyle changes or treatments are working.

The underlying method is RSOM, short for Raster Scan Optoacoustic Mesoscopy. It fires pulses of light into tissue, which generate ultrasound signals that are then turned into detailed 3D images of structures beneath the skin. It can pick up small changes in blood vessels, oxygen levels, and tissue composition that traditional imaging misses. Combining high contrast with depth, RSOM may also enable early detection of diseases such as diabetes. The technology was developed by the group led by Prof. Vasilis Ntziachristos, Director of the Bioengineering Center at Helmholtz Munich and Professor for Biological Imaging at TUM.

Ntziachristos argues that by enabling earlier intervention and more precise monitoring, fast-RSOM could change how cardiovascular disease is prevented and managed, improving patient outcomes and lowering health care costs over the long term. Because the device is portable, fast, and noninvasive, the team envisions it one day being used in outpatient clinics for routine risk assessment.

That day has not arrived. The next steps are to validate fast-RSOM in larger and more diverse patient groups and to work its biomarkers into clinical workflows.