What’s New in Photon Counting CT?

May 26, 2026 · 6 articles · 10 research themes · covering May 19, 2026 – May 26, 2026

Overview

This week’s set of studies highlights rapid progress in photon-counting detector CT (PCD-CT), with multiple papers focusing on how acquisition and reconstruction choices translate into measurable differences in diagnostic performance. In coronary imaging, ultra-high-resolution PCD-CT enables more reliable visualization and quantification despite metal-related artifacts: a case report showed that spectral iodine mapping and high-resolution PCD-CT could noninvasively characterize in-stent occlusion and identify a nonviable transmural myocardial scar. Complementing this, phantom work demonstrated that quantum iterative reconstruction can materially shift quantitative stent metrics (e.g., lumen diameter and strut thickness), underscoring that “what you measure” depends on the reconstruction pipeline.

Across other clinical targets, protocol optimization emerges as a central theme. For emergency non-contrast head CT, a retrospective comparison found PCD-CT can deliver comparable or improved quantitative image quality at reduced dose versus energy-integrating CT, with performance sensitive to acquisition settings. For temporal bone imaging, a phantom-and-clinical study identified dose-reduction limits that preserve detectability, supporting safer lower-dose PCD-CT protocols. Finally, a prospective study using deep learning for coronary plaque quantification showed that changing reconstructed spatial resolution affects both subjective image quality and the deep learning tool’s estimates of stenosis and plaque volumes—reinforcing the need to match reconstruction parameters to the intended quantitative task.

In parallel, a scoping review synthesized pediatric imaging practices and evidence from 2015–2025, emphasizing evolving modality-specific techniques and reporting standards to guide safer imaging decisions in children. Together, these articles point toward a future where PCD-CT’s advantages are realized not only through hardware, but through careful, task-specific optimization of dose, reconstruction settings, and quantitative analysis methods.

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Myocardial Viability & Scar Characterization

Photon-Counting Computed Tomography for In-Stent Occlusion: Lumen Visualization and Myocardial Viability.

This case report studied ultra-high-resolution photon-counting detector computed tomography (PCCT) in a 58-year-old man with prior right coronary artery stenting and suspected in-stent occlusion. PCCT demonstrated chronic total in-stent occlusion with robust LAD-to-RCA collateral flow, and spectral iodine mapping identified a nonviable transmural myocardial scar. The findings highlight PCCT’s ability to noninvasively visualize coronary stent lumen despite metal blooming and to characterize myocardial viability in a single acquisition.

Nguyen KV, Nguyen VT, Nguyen NT et al. · JACC. Case reports · (2026) · View on PubMed ↗ · Free PDF ↗

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Reconstruction Parameters (Spatial Resolution) in PCD-CT

Deep Learning-Based Automated Coronary Plaque Quantification with Ultra-high Resolution Photon-Counting Detector CT at Different Spatial Resolutions.

This prospective single-center study evaluated deep learning–based automated coronary plaque quantification using ultra-high-resolution photon-counting detector CT (UHR-PCD-CT) at three reconstructed spatial resolutions (0.6 mm SR, 0.4 mm HR, 0.2 mm UHR) in 70 patients with suspected coronary artery disease. The key finding was that changing spatial resolution affected subjective image quality and the deep learning tool’s quantification of coronary stenosis and plaque volumes. This supports selecting reconstruction resolution to balance image quality and quantitative plaque assessment accuracy with PCD-CT.

Liu Y, Li R, Zhang H et al. · Academic radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Reconstruction Algorithms (Iterative Reconstruction) in PCD-CT

Effect of quantum iterative reconstruction on coronary stent assessment in ultra-high resolution photon-counting detector CT: a phantom study.

This phantom study tested the effect of quantum iterative reconstruction (QIR) on coronary stent assessment in ultra-high-resolution photon-counting detector CT (UHR-PCD-CT). In a 3D-printed coronary phantom with multiple stent types, QIR altered objective metrics including contrast-to-noise ratio (CNR), lumen diameter, and stent strut thickness at 120 and 140 kVp. The findings suggest QIR can meaningfully influence quantitative stent evaluation on PCD-CT, informing reconstruction choices for more reliable in-stent measurements.

Scheuer ST, Kusk MW, Sæderup H et al. · European radiology experimental · (2026) · View on PubMed ↗ · Free PDF ↗

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Non-Contrast Head CT Image Quality (Emergency/Acute)

Photon Counting CT of the Head: Retrospective Analysis of Image Quality and Dose in Comparison to Energy Integrating Detector CT.

This retrospective study compared photon-counting detector CT (PCD-CT) versus energy-integrating detector CT (EID-CT) for non-contrast head CT (NCCT) image quality and radiation dose across different PCD-CT acquisition settings (120 vs 140 kVp and varying dose). PCD-CT achieved comparable or improved quantitative image quality at reduced dose relative to EID-CT, with performance varying by acquisition parameters. Scientifically and clinically, the results support optimizing PCD-CT protocols for emergency NCCT while maintaining diagnostic image quality.

Schoenbeck D, Kroeger JR, Moenninghoff C et al. · Academic radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Temporal Bone CT Imaging (Dose & Detectability)

Appropriate dose reduction using photon-counting detector CT for temporal bone imaging: phantom and clinical studies with helical acquisition.

This phantom-and-clinical study assessed how much radiation dose could be reduced with photon-counting detector CT (PCD-CT) for temporal bone imaging while maintaining image quality equivalent to standard-dose energy-integrating detector CT (EID-CT). Using visual scoring and detectability index (d’) measurements across dose levels, the authors identified a dose-reduction limit for PCD-CT that preserved temporal bone image quality. The work is significant for implementing lower-dose temporal bone CT protocols using PCD-CT without sacrificing diagnostic detectability.

Takahashi Y, Higaki F, Nakamura Y et al. · Japanese journal of radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Pediatric Imaging Practices & Evidence Synthesis

Innovations in pediatric imaging: a scoping review of the past decade with case illustrations.

This scoping review examined pediatric imaging practices and evidence from 2015–2025 across modalities including ultrasound, X-ray, CT, and MRI, using MEDLINE searches and additional institutional case illustrations. The review synthesized how imaging is used in pediatric diagnostic work-ups and emphasized evolving techniques and reporting practices over the past decade. Clinically, it provides a structured overview to guide safer, more effective imaging choices in children and to identify gaps for future research.

Beer MJ, Schaal MC, Neubauer H · World journal of pediatrics : WJP · (2026) · View on PubMed ↗ · Free PDF ↗

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Generated automatically on May 26, 2026. Covers PubMed articles published May 19, 2026 – May 26, 2026. Summaries are AI-generated; always consult the original publication for clinical or research decisions.