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Ultrasound CT use in intensive care units and emergency departments may soon become a reality as the result of a recent seismology-based discovery.

A seismology-based discovery from an interdisciplinary scientific team may soon enable the use of ultrasound computed tomography (USCT) for pulmonary imaging in intensive care units (ICUs) and emergency departments (EDs), according to a study published in IEEE Transactions on Biomedical Engineering.

The Challenge of Portable Lung Imaging

USCT offers rapid, portable, ionizing-radiation-free imaging, but its adoption in ICUs and EDs has stalled, according to a Colorado State University (CSU) press release. This is because, unlike rigid computed tomography (CT) gantries, USCT employs a flexible belt of transmit-receive sensors that slips with every breath, blurring the time-of-flight data needed for high-resolution reconstruction.

“USCT has the potential to provide a real-time response to developing conditions that could be treated sooner rather than later,” noted study author and CSU mathematician Jennifer Mueller, PhD. “Yet the method is crippled if we cannot pinpoint where the sensors are during acquisition.”

A Cross-Disciplinary Insight From Seismology

According to the press release, the breakthrough came when study co-author Roberto Ceccato, a University of São Paulo doctoral engineer interning in Mueller’s lab, consulted study co-author and CSU geophysicist Rick Aster. Seismologists correct earthquake data for near-surface irregularities using “static corrections” that infer location-dependent travel-time shifts. Applying the same mathematics to the human thorax, the team treated transducer-position error as an unknown static term and folded its estimation into image reconstruction.

“USCT is applying seismology to the human body,” Aster remarked.

Algorithm Development & Phantom Validation

The researchers embedded the static-correction concept in a quantitative time-of-flight USCT framework tailored to low-frequency (lung-penetrating) waves. A modified Barzilai–Borwein step-size rule reoriented steepest descent updates, while total variation regularization curbed noise amplification. Simulations using MATLAB’s k-Wave toolbox, a programming and numerical computing platform, on healthy and diseased chest models showed marked gains in spatial fidelity and successful retrieval of sensor coordinates. Experiments with an ultrasound system and ballistic-gel torsos reproduced the improvements under clinically realistic conditions, according to findings.

Toward Clinical Translation

“This study is the first to address transducer location uncertainty on a transducer belt in TFTM (time of flight transmission mode) USCT and to apply an estimated gradient approach (at pulmonary frequencies),” the authors wrote.

“With this solution, continuous lung monitoring at the bedside becomes more practical, helping physicians make more informed decisions about mechanical ventilation strategies and track lung health in conditions such as COVID-19,” Ceccato said.

According to the press release, Mueller’s group has already confirmed compliance with US FDA acoustic-output limits in porcine models and anticipates imminent human feasibility trials. If successful, the portable system could deliver rapid, radiation-free lung assessments without requiring the movement of fragile patients—an advance born from the convergence of mathematics, engineering, and geophysics.