What’s New in Photon Counting CT?

September 20, 2026 · 7 articles · 7 research themes · covering September 13, 2026 – September 20, 2026

Overview

Across this week’s PubMed set, photon-counting CT (PCCT/PCD-CT) is advancing along two complementary tracks: (1) clinical performance for specific, high-stakes diagnostic questions, and (2) technical optimization to make the modality more quantitative and dose-efficient.

Clinically, PCCT is being tested for post-procedural cardiovascular assessment—detecting in-stent restenosis with graded image quality suitable for clinical interpretation, and predicting prosthetic valve dysfunction after TAVI by combining CT-derived anatomy with time-resolved hemodynamic parameters. In atrial fibrillation, PCCT-based quantification of epicardial adipose tissue using semiautomated 3D segmentation is linked to recurrence after catheter ablation, suggesting a pathway toward imaging-guided risk stratification. Outside cardiology, PCCT shows promise for otosclerosis surgical planning by improving detection of stapes footplate fixation, and for lung disease evaluation by enabling ultra-low-dose imaging while preserving automated quantitative CT metrics and reader interpretability.

On the methods side, a phantom study addresses a key practical question for spectral imaging: how tube voltage (kV) affects virtual monoenergetic image (VMI) CT values and contrast-to-noise ratio, informing acquisition choices for quantitative consistency. A narrative review consolidates these detector-physics advantages—better spatial resolution, reduced noise/metal artifacts, and spectral capabilities—into head-and-neck workflows, reinforcing PCCT as a “bridge” from technology to routine pre- and postoperative imaging.

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Photon-Counting CT for Coronary/Ischemic Heart Disease (Stents & ISR)

In vivo coronary stent evaluation using photon-counting computed tomography: diagnostic performance.

This retrospective single-center study evaluated photon-counting CT (PCCT) coronary angiography in 141 consecutive patients with coronary stents to detect in-stent restenosis (ISR) ≥50% using invasive coronary angiography (ICA) as the reference, comparing PCCT with energy-integrating detector (EID)-CT. PCCT demonstrated diagnostic performance for ISR detection and produced graded in-stent lumen image quality (excellent/limited/nondiagnostic) suitable for clinical assessment. These findings support PCCT coronary CTA as a potentially more accurate and/or higher-quality noninvasive approach for post-stent ISR evaluation, with implications for reducing reliance on invasive angiography.

Lacaita PG, Bilgeri V, Spitaler P et al. · European radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Photon-Counting CT for Temporal Bone & Otosclerosis (Stapes Fixation)

Photon-counting CT for preoperative assessment of stapes footplate fixation in otosclerosis.

This retrospective case series studied photon-counting CT (PCCT) of the temporal bone in 18 patients with surgically confirmed otosclerosis to identify stapes footplate fixation and to quantify missed findings on initial radiology reports. PCCT imaging findings of stapes footplate involvement (e.g., increased thickness and/or hypoattenuation) correlated with intraoperative confirmation, and the authors assessed how often these signs were overlooked preoperatively. The results suggest PCCT may improve pre-surgical detection of stapes fixation in otosclerosis and reduce diagnostic misses that can affect surgical planning.

Arora M, Seyedsaadat SM, Breen JT et al. · European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · (2026) · View on PubMed ↗

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Photon-Counting CT for Lung Imaging at Ultra-Low Dose

Quantitative and qualitative lung parameters in photon-counting CT: comparison of ultra-low-dose with standard low-dose protocols.

In a prospective same-session study of 101 patients, the authors compared ultra-low-dose (ULD) versus standard low-dose (LD) photon-counting CT (PCCT) for quantitative and qualitative lung assessment using automated quantitative CT (QCT) metrics and reader image-quality scoring. ULD PCCT altered quantitative lung parameters (including noise index, airway segmentation metrics, emphysema index, mean lung density, and Percentile 15) and affected qualitative evaluation of airways and emphysema compared with LD. These data clarify how far PCCT can be pushed to lower radiation dose while preserving clinically usable lung quantification and image interpretability.

Kroschke J, Jungblut L, von Stackelberg O et al. · European radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Photon-Counting CT for Cardiac Valve Dysfunction (TAVI)

Photon-counting detector CT for prediction of valve dysfunction after transcatheter aortic valve implantation: Comparison with echocardiography.

This retrospective single-center study assessed time-resolved photon-counting detector CT (PCD-CT)–derived hemodynamic parameters in post–transcatheter aortic valve implantation (TAVI) patients to predict prosthetic valve dysfunction, excluding cases with severe mitral regurgitation and using echocardiography as the comparator. The key finding was that PCD-CT functional assessment provided diagnostic accuracy for valve dysfunction prediction relative to echocardiography by combining CT-derived anatomic measurements (e.g., prosthetic valve orifice area) with hemodynamic parameter estimation. Clinically, this supports PC D-CT as a noninvasive tool to better characterize suspected TAVI dysfunction when both anatomy and function are needed.

Hyska S, Osoria-Velasquez J, Hagar MT et al. · Journal of cardiovascular computed tomography · (2026) · View on PubMed ↗ · Free PDF ↗

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Photon-Counting CT for Atrial Fibrillation & Ablation Risk (Epicardial Adipose Tissue)

Epicardial adipose tissue in paroxysmal and persistent atrial fibrillation ablation using photon counting CT and automated 3D atrial segmentation: The Prospective AFAT Study.

The Prospective AFAT Study prospectively quantified epicardial adipose tissue (EAT) in 210 adults undergoing first-time catheter ablation for paroxysmal or persistent atrial fibrillation using photon-counting CT (PCCT) with semiautomated 3D biatrial segmentation. The study found associations between volumetric EAT measures and arrhythmia recurrence after ablation, linking PCCT-based body composition quantification to ablation outcomes. These results suggest that PCCT-derived EAT quantification could help risk-stratify patients and refine prediction of recurrence after AF ablation.

Erhard N, Bahlke F, Prommersberger S et al. · Heart rhythm · (2026) · View on PubMed ↗ · Free PDF ↗

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Photon-Counting CT Clinical Translation in Head & Neck Imaging (Review)

Photon-counting CT in head and neck radiology: bridging detector physics and clinical applications.

This narrative review summarized how photon-counting computed tomography (PCCT) differs from conventional energy-integrating detector CT (EID-CT) and highlighted its technical advantages for head and neck imaging. The authors emphasized improved spatial resolution, reduced noise and metal artifacts, lower radiation dose and iodinated contrast dose, and spectral imaging capabilities, translating these into clinical applications such as visualization of small vessels, ossicles, and cartilage for preoperative planning and postoperative assessment. The review positions PCCT as a bridging technology from detector physics to practical head-and-neck diagnostic workflows.

Martín-Noguerol T, Escartín J, López-Úbeda P et al. · European radiology · (2026) · View on PubMed ↗

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Photon-Counting CT Technical/Physics Foundations (Spectral/VMI & Acquisition Parameters)

Influence of X-ray Tube Voltage on Computed Tomography Values and Contrast-Noise Ratios in Virtual Monoenergetic Images in routine clinical Photon Counting Detector Computed Tomography: Does kV Still Matter?

This phantom study investigated how X-ray tube voltage (kV) influences computed tomography values and contrast-to-noise ratios in virtual monoenergetic images (VMI) generated from routine clinical photon-counting detector CT (PCD-CT). Across tissue types, VMI keV levels, phantom sizes, and kV settings, the authors tested whether VMI CT values depend on tube voltage and identified kV settings that optimize contrast-to-noise ratio for a given VMI energy. The findings inform how to select acquisition parameters for quantitative consistency in PCCT-based spectral imaging, addressing whether kV still matters despite monoenergetic reconstruction.

Jeukens CRLPN, Pinckaers FME, Martens B et al. · Investigative radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Generated automatically on September 20, 2026. Covers PubMed articles published September 13, 2026 – September 20, 2026. Summaries are AI-generated; always consult the original publication for clinical or research decisions.