Scientists at the California Institute of Technology and the University of Southern California have developed RUS-PAT, a new 3D imaging technology that combines ultrasound and laser light. This hybrid system captures both anatomy and vascular function in high-resolution “optical color.”

Researchers at the California Institute of Technology (Caltech) and the University of Southern California (USC) have developed a hybrid imaging system that provides a three-dimensional, color-coded view of the human body.

a technique called Hybrid Rotational Ultrasound and Photoacoustic Tomography (RUS-PAT), It integrates two different modalities to capture both the physical structure of the soft tissue and the functional details of the blood vessels within it.

The study, published in the January 16, 2026 issue of Nature Biomedical Engineering, demonstrates how the system can visualize complex anatomical structures such as the brain, breast, hands, and feet in less than a minute.

Bridge structure and function by RUS-PAT

Standard ultrasound examinations are a staple of clinical medicine because they are quick and affordable, but they generally produce two-dimensional images, making it difficult to show functional details of blood flow. Photoacoustic tomography (PAT), a field pioneered by Lihong Wang at the California Institute of Technology, uses laser pulses to make molecules in the body vibrate. These vibrations generate sound waves that detectors can map to show the “optical color” of vascular structures, revealing how blood moves through veins and arteries.

By combining these two methods into the RUS-PAT platform, the team created a tool that provides both morphological and functional data simultaneously. This dual-contrast approach allows clinicians to precisely locate tumors and lesions while monitoring oxygen delivery and vascular health.

Innovative design and efficiency using ultrasonic transducers

To commercialize the system for clinical use, the researchers developed a design that uses a single-element ultrasound transducer to transmit waves over a large area. A small number of arc-shaped detectors are then rotated around the target area. This allows the device to function like a high-end hemispherical detector, while significantly reducing cost and complexity.

In human experiments, the system achieved a 10-centimeter field of view with sub-millimeter resolution. Unlike CT scans and MRIs, RUS-PAT does not require ionizing radiation, powerful magnets, or expensive contrast agents.

Clinical applications and future developments

The research team identified several high-priority applications for this technology.

• Oncology:
  • Improve breast tumor imaging by revealing the precise location and physiological state of the tumor.
• Diabetes:
  • Monitoring nerve damage and blood supply in patients with diabetic neuropathy.
• Neurology:

The current prototype houses the scanner under a special bed that can reach a depth of about 4 centimeters. Researchers are currently investigating how to transmit light through an endoscope to reach deeper tissues and improve the clarity of broader signals through the human skull. Brain imaging application.