Sunday, November 25 | 10:45 a.m.-10:55 a.m. | SSA05-01 | Room E451A
U.S. researchers used photon-counting CT scans of the chest to capture tiny details in patients' lungs, with notably higher spatial resolution than conventional CT, according to this study to be presented on Sunday.Early research on phantoms and cadavers has shown that photon-counting detectors have the potential to replicate, if not surpass, the image quality of conventional CT scanners at a considerably lower radiation dose because of their high signal-to-noise ratio.
Seeking to build on this prior work, Dr. David Bartlett and colleagues from the Mayo Clinic in Rochester, MN, acquired photon-counting chest CT scans of 22 patients at their institution. They set the photon-counting CT scanner to "sharp" mode, which provided a 150-micron pixel size, and also reconstructed the resulting scans with a large image matrix (1024 x 1024).
Compared with the 350-micron pixel size and 512 x 512-matrix size of conventional CT, photon-counting CT offered better visualization of patient airways. The two chest radiologists who read the scans reported statistically significant improvements in their ability to identify details in the lungs, including small bronchi, nodules, and bronchial walls.
"The results of this study demonstrated the potential benefit of high-resolution photon-counting chest CT, particularly in assessing airway diseases," Bartlett told AuntMinnie.com. "The data also suggest that the photon-counting CT system offers benefits in visualizing other pathologies, such as fibrosis, honeycombing, and emphysema."
This paper received a Roadie 2018 award for the most popular abstract by page views in this Road to RSNA section.
![Axial images from unenhanced calcium score cardiac CT (left) and curved planar reformation images from CT angiography (right) show that higher long-term exposure to air pollution is associated with greater coronary artery calcium and more obstructive coronary artery disease (CAD). Top row: Images in a 68-year-old male patient with higher 10-year mean ambient air pollution exposure (7.9 μg/m3 for particulate matter measuring ≤2.5 μm in diameter [PM2.5] and 17.4 parts per billion [ppb] for NO2) with extensive CAD (coronary artery calcium score [CACS] >1,000 and obstructive CAD [≥70% diameter stenosis]). Bottom row: Images in a 57-year-old female patient with lower 10-year mean ambient air pollution exposure (6.3 μg/m3 for PM2.5 and 4.6 ppb for NO2) with no CAD (CACS = 0 and no obstructive stenosis).](https://img.auntminnie.com/mindful/smg/workspaces/default/uploads/2026/06/hanneman.r6SMLzkezo.png?auto=format%2Ccompress&dpr=2&fit=crop&h=167&q=70&w=250)
