Ronan Smith, a postdoctoral research fellow at Adelaide University, has been awarded the prestigious Physics in Medicine & Biology (PMB) Early Career Researcher Award for his groundbreaking work in X-ray velocimetry (XV). This award recognizes the best paper in PMB's 2025 Early Career Researcher Focus Collection, and Smith's research has made significant contributions to the field of lung imaging and treatment.
In his award-winning paper, "Visualising ventilation changes following endobronchial valve placement with x-ray velocimetry functional lung imaging," Smith explores the potential of XV to detect changes in lung function after the insertion of endobronchial valves (EBVs). EBVs are used to treat emphysema, a condition that damages the air sacs in the lungs, making breathing difficult. By using XV imaging, Smith's research demonstrates a non-invasive method to measure regional and local changes in airflow, providing valuable insights into the clinical impact of EBV placement.
The study involved a pilot on healthy sheep, which have similar lung sizes to humans. The XV scanning process recorded fluoroscopic videos of individual breaths at various angles, with anatomic positioning provided by breath-hold CT scans. The 4DMedical software correlated motion in the XV videos with CT data, creating a 3D map of specific ventilation in small voxels throughout the lungs. This mapping allowed for the calculation of mean specific ventilation and ventilation heterogeneity across lung regions.
One of the key findings was that XV imaging could visualize and quantify a reduction in airflow to areas downstream of the valves, even in regions where collapse was not visible in CT scans. This highlights the advantage of XV over CT in assessing lung function changes. Smith emphasizes the importance of this research for people with emphysema, as improved placement and verification tools will lead to better treatment options.
Since the publication of this paper, Smith has been working on further applications of XV imaging, including a world's first paediatric clinical trial examining the feasibility of using XV in children with cystic fibrosis. The trial has imaged around 30 children and aims to publish findings later this year. Smith is also developing dark-field X-ray imaging, another novel X-ray imaging method.
Smith's excitement about receiving the PMB Early Career Researcher Award is understandable. The award acknowledges the collaborative efforts of clinicians, scientists, and various organizations, including 4DMedical and the preclinical imaging facility. As a physicist working in medicine and biology, this award feels like a perfect recognition of his contributions to the field. The award also serves as evidence of the interest in his work and will help convince funding bodies of the importance of continuing this research.
