A New Window Into Microvascular Health
One of the earliest warning signs of cardiovascular disease happens deep within the smallest blood vessels: tiny changes in their ability to expand and contract, known as microvascular endothelial dysfunction (MiVED). Until now, doctors had no precise and non-invasive way to see or measure these early changes in humans.
“With fast-RSOM, we can, for the first time, non-invasively assess endothelial dysfunction at single-capillary and skin-layer resolution in humans,” says Dr. Hailong He, first author of the study and researcher at the Institute of Biological and Medical Imaging at Helmholtz Munich and TUM. Dr. Angelos Karlas, co-first author, Vascular Surgeon and Senior Research Scientist at TUM University Hospital, adds: “Our novel approach offers an unprecedented view of how cardiovascular disease manifests at the microvascular level.”
Detecting Progression Before Symptoms Appear
Fast-RSOM provides high-resolution, dynamic MiVED biomarkers, describing subtle impairments in blood vessel function, that are generally present before clinical symptoms or measurable macroscopic disease features appear. These early changes are often linked to risk factors such as smoking, high blood pressure, or obesity. However, in contrast to computing risk based on descriptive conditions, fast-RSOM can quantitatively capture the actual changes that these conditions have imposed on the microvascular system – long before major complications develop.
By capturing these early warning signs, fast-RSOM opens up new possibilities for early detection, prevention, and more precise monitoring of cardiovascular health. The technology could help identify individuals at higher risk of developing cardiovascular events with higher precision and monitor lifestyle or therapeutic interventions.
Towards Clinical Application
The research team now aims to validate fast-RSOM in larger and more diverse patient groups and to integrate its biomarkers into clinical workflows. Because the device is portable, fast, and non-invasive, it could one day be used in outpatient clinics for routine cardiovascular risk assessment.
“By enabling earlier interventions and more precise monitoring, fast-RSOM could transform how cardiovascular diseases are prevented and managed – improving outcomes for patients and reducing healthcare costs in the long term,” says Prof. Vasilis Ntziachristos, Director of the Bioengineering Center at Helmholtz Munich and Professor for Biological Imaging at TUM.
What is RSOM?
RSOM (Raster Scan Optoacoustic Mesoscopy) is a non-invasive imaging technology that uses pulses of light to generate ultrasound signals, producing highly detailed 3D images of structures beneath the skin. It can detect tiny changes in blood vessels, oxygen levels, and tissue composition that are invisible to traditional imaging. By combining high contrast with depth, RSOM enables early detection of diseases such as cardiovascular problems and diabetes. Its compact design could make advanced diagnostics more accessible outside specialized labs. The technology was developed by the team under Vasilis Ntziachristos.
Original Publication
He et al., 2025: Single-Capillary Endothelial Dysfunction resolved by Optoacoustic Mesoscopy. Light: Science & Applications. DOI: 10.1038/s41377-025-02103-6
