Whole Cross-Section Ultrasound System Enables Operator-Independent Imaging

Comprehensive cross-sectional assessment typically requires computed tomography or magnetic resonance imaging, which can be slower, costly, or expose patients to ionizing radiation. These constraints complicate rapid triage and longitudinal monitoring in acute and perioperative care. Researchers have now developed a whole cross-section ultrasound tomography system to deliver fast, operator‑independent views of large body regions.

The whole cross-section ultrasound tomography (UST) system was developed at the California Institute of Technology (Caltech; Pasadena, CA, USA). It scans a seated participant in a water‑immersion tank using a ring of 512 ultrasound transducers that traverses vertically to acquire consecutive body cross-sections. The platform records echo, transmission, and attenuation signals, enabling mapping of tissue boundaries while quantifying speed of sound and energy loss through different structures. This design aims to reduce compression artifacts and minimize dependence on user technique.

In early testing, the team scanned the abdomens of five healthy volunteers, capturing each cross-section in 10 seconds. The device imaged deep structures and produced images similar to those from established whole‑body modalities. Study details and technical specifications were published on April 24, 2026, in Nature Biomedical Engineering.

Planned evaluations include patients with liposarcoma, a rare malignancy that originates in fat cells and is often difficult to visualize because tumors can be deep and have ill‑defined features. The researchers are collaborating with City of Hope Medical Center to assess the system for liposarcoma identification and monitoring. 

The group also describes a horizontal‑bed redesign that would use a thin water pouch and conductive gel, with potential for real‑time image guidance during surgery and biopsies. Additional possibilities noted include early tumor detection in organs such as the liver and pancreas, musculoskeletal assessment of soft‑tissue injury, and frequent longitudinal imaging to track disease progression or treatment response.

“When tissue varies, it can be used as an indicator of certain diseases such as chronic inflammation and cancer. For example, if there’s solidification of tissue due to a tumor, it becomes stiffer, and the echogenicity, speed of sound, or attenuation can change as it encounters that tissue. The more physical parameters we can quantify, the better the chance that we can correlate those measurements with physiologically meaningful parameters to help us diagnose different diseases,” said Lihong Wang, Bren Professor of Medical Engineering and Electrical Engineering and Andrew and Peggy Cherng Medical Engineering Leadership Chair and executive officer for medical engineering at Caltech.

“Much like a standard whole-body X-ray, MRI, or PET scan, our system is operator independent. It offers a large field of view because you see the entire cross-section and it doesn’t compress the tissue, which can cause distortion. Plus, ultrasound is entirely harmless to patients, which is a big advantage over techniques that use ionizing radiation,” said Wang.

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