Photon Counting CT Technology in Cardiovascular Imaging

Photon-counting computed tomography (PCCT) is a new technology that uses detectors, which discriminate the energy of individual photons in the x-ray beam and convert detected individual photons into electric signals. It offers multiple advantages over standard energy-integrating detector CT including uniform photon weighting across multiple x-ray energies, improving image quality; small detector-pixel design, increasing spatial resolution; energy thresholding, eliminating electronic image noise; energy binning, permitting detection and quantification of multiple materials to enhance tissue characterization and overall improvement in the reproducibility of image quality.

The impact of this new generation CT on the evaluation of the cardiovascular system could be profound. PCCT provides better image quality to evaluate disease processes at lower radiation dose. Also, PCCT offers excellent spatial resolution, and perfect spatial alignment and could reduce certain CT artifacts. Many applications of dual-energy CT imaging are limited in cardiovascular imaging because dual-energy acquisition on dual-source systems requires slower scan speeds. This can make the evaluation of smaller structures, especially if these are constantly in motion (like the heart valves and coronary arteries) more challenging. Assessment of coronary stents is also limited with current CT scanners.

Cardiovascular CT could benefit from the information gained through multi-energy scans. The ability to discriminate reliably between coronary calcium and iodine-containing contrast would be very valuable in clinical practice. Further reducing the blooming artifacts due to the vastly improved spatial resolution could improve the diagnostic performance of PCCT. Furthermore, spectral information is available for all PCCT scans that improve the visualization of other abnormalities beyond coronary atherosclerosis, such as myocardial perfusion deficits, using different virtual monoenergetic images. The quantification of iodine density is also available.

The goal of this Research Topic is to show how photon-counting CT can deliver the highest acquisition speed with full spectral information, higher contrast, and spatial resolution for the evaluation of multiple diseases of the cardiovascular system. The project also aims to elucidate the role of novel applications using spectral CT data in cardiovascular imaging.

We are interested in papers highlighting specific strengths of photon-counting CT in the imaging of cardiovascular diseases, such as:
1) Valvular heart disease.
2) Coronary artery disease, especially using the true-lumen feature that allows for calcium removal based on material decomposition.
3) Diagnostic performance of PCCT in ischemic heart disease.
4) Myocardial perfusion imaging, where photon-counting CT could be able to be more of a match to MRI than previous CT generations.
5) Stent evaluation.
6) The use of virtual monoenergetic images to improve the diagnostic value of cardiac CTA.

Keywords: Photon Counting, CT Technology, Computerized Tomography

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.