What’s New in Photon Counting CT?

August 29, 2026 · 10 articles · 11 research themes · covering August 22, 2026 – August 29, 2026

Overview

This week’s set of studies and reviews converges on a central theme: photon-counting detector CT (PCD/PCCT) is moving from “better images” toward measurable, protocol-relevant advantages—higher spatial resolution, improved contrast-to-noise, and more reliable quantitative material information. Across coronary CTA, CT pulmonary angiography, and cerebrovascular CTA, PCCT/PCD-CT consistently shows potential to reduce artifacts (e.g., calcium blooming/stent-related issues), improve lesion characterization, and support more confident clinical reporting—while also enabling more evidence-based comparisons of radiation and iodine burden.

A second dominant thread is the push to make PCCT quantitative and reproducible. Work on spectral/multi-material decomposition highlights how x-ray pre-filtration can materially change decomposition accuracy depending on filter and target materials. Complementing this, experimental and phantom studies show that measured microstructural metrics (e.g., trabecular parameters) depend strongly on acquisition dose, spatial resolution, and reconstruction strategy—underscoring the need for optimized, standardized PCCT protocols if quantitative biomarkers are to be trusted.

Finally, several clinical feasibility/phenotyping studies illustrate how PCCT’s technical strengths translate into niche but impactful applications: stress CT myocardial perfusion after arterial switch operation, noninvasive atrial fibrillation substrate characterization via septal/SA-node structural markers, direct morphometric assessment of the vestibular aqueduct for Menière’s disease endotypes, and even neonatal airway device placement using photon-counting CT. Together, these papers suggest PCCT is broadening beyond cardiopulmonary imaging into patient-specific anatomical and functional phenotyping—provided that quantitative methods are carefully validated.

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Photon-counting CT (PCCT) spectral/multi-material decomposition and pre-filtration

Material-dependent effects of x-ray pre-filtration on material decomposition in photon-counting CT.

This phantom-based study characterized how x-ray pre-filtration affects material decomposition performance in photon-counting CT (PCCT) across different filter materials and thicknesses using contrast agents spanning low-Z (iodine, barium) and high-Z (tantalum) compositions. The key finding was that pre-filtration conditions materially changed the accuracy/performance of material decomposition basis maps, with effects depending on the filter material/thickness and the target contrast material (iodine/barium vs tantalum). This is significant because it informs how to choose pre-filtration to improve quantitative multi-material imaging in PCCT.

Aubrey JD, Perkinson EP, Wang G et al. · Physics in medicine and biology · (2026) · View on PubMed ↗

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Coronary CT angiography (CCTA) with photon-counting detectors

Diagnostic performance and clinical impact of photon-counting detector computed tomography in coronary artery disease.

This review synthesized recent evidence on photon-counting detector CT (PCD-CT) for diagnosing coronary artery disease (CAD), focusing on how the technique addresses limitations of conventional energy-integrating detector CT (EID-CT). The key finding across included studies was that PCD-CT provides superior spatial resolution, improved contrast-to-noise ratio, and reduced calcium blooming and stent-related artifacts versus EID-CT. Clinically, this supports PCD-CT as a promising next-generation approach to improve coronary CTA diagnostic performance and potentially downstream decision-making in CAD.

Parikh R, Shin D, Ali ZA et al. · Current opinion in cardiology · (2026) · View on PubMed ↗

Is nitroglycerin still necessary for coronary CT angiography in the era of photon-counting CT?

This retrospective single-center study assessed whether sublingual nitroglycerin remains necessary for coronary CT angiography (CCTA) when using photon-counting detector CT (PCD-CT), comparing diagnostic performance against invasive coronary angiography within 30 days in 124 patients (including 61 who received nitroglycerin). The key finding was that the study evaluated the incremental diagnostic value of nitroglycerin specifically for PCD-CT CCTA rather than relying on older-generation CT evidence. This is significant because it could streamline CCTA protocols by potentially reducing unnecessary medication if diagnostic accuracy is maintained with PCD-CT.

Kabakus IM, Maisuria DM, Chamberlin JH et al. · Journal of cardiovascular computed tomography · (2026) · View on PubMed ↗ · Free PDF ↗

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Coronary CT stress myocardial perfusion imaging (CT-MPI) with photon-counting detectors

Stress CT myocardial perfusion imaging after arterial switch operation for transposition of the great arteries.

This feasibility and diagnostic-performance study evaluated stress CT myocardial perfusion imaging (CT-MPI) in adults after arterial switch operation for transposition of the great arteries (ASO-TGA), comparing regadenoson stress CT-MPI using dynamic energy-integrating detector CT (EID-CT) with quantitative myocardial blood-flow mapping versus static photon-counting detector CT (PCCT) with qualitative/semiquantitative iodine-map assessment. The key finding was that stress CT-MPI using PCCT iodine-map assessment was feasible and diagnostically informative for detecting coronary abnormalities in this post-ASO adult population. Clinically, it supports PCCT-based stress CT-MPI as a potential noninvasive option to evaluate late coronary complications after ASO-TGA.

Gkizas C, Longere B, Domanski O et al. · European heart journal. Imaging methods and practice · (2026) · View on PubMed ↗ · Free PDF ↗

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CT pulmonary angiography (CTPA) with photon-counting detectors

Photon-counting detector CT for CT pulmonary angiography: a systematic review and meta-analysis.

This systematic review and meta-analysis compared photon-counting detector CT (PCCT) with energy-integrating detector CT (EID-CT) for CT pulmonary angiography (CTPA), evaluating radiation dose, contrast media utilization, image quality (SNR/CNR), and diagnostic performance across 12 studies (950 patients). The key finding was that pooled analyses quantified differences in CT dose index volume, total iodine load, and image-quality metrics between PCCT and EID-CT, supporting an evidence-based comparison of performance and efficiency. Clinically, it helps determine whether PCCT can deliver improved image quality and/or reduced radiation/iodine burden for CTPA.

Kato S, Azuma M, Horita N et al. · European radiology · (2026) · View on PubMed ↗

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Cerebrovascular CTA with photon-counting detectors

Detection and Characterization of Infundibula and Aneurysms: A Clinical Report-Based Comparison of PCD- and EID-CTA.

This clinical report-based retrospective comparison evaluated paired head/neck CTA interpretations in adults with arterial outpouchings, comparing photon-counting detector CTA (PCD-CTA) versus energy-integrating detector CTA (EID-CTA) for concordance in lesion detection and characterization (aneurysm vs infundibulum vs uncertain). The key finding was that higher spatial resolution from PCD-CTA affected how lesions were classified in routine clinical reporting compared with EID-CTA. This matters because it could reduce diagnostic uncertainty and improve triage decisions for cerebral arterial outpouchings.

Jacobson Z, El Sadaney AO, Yu L et al. · AJNR. American journal of neuroradiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Neurotology and temporal bone imaging with photon-counting CT

The angular trajectory of the vestibular aqueduct: evaluation using photon-counting CT.

This retrospective study used photon-counting CT (PCCT) temporal bone scans from 64 patients (128 ears) to directly visualize the proximal vestibular aqueduct and measure the angular trajectory of the vestibular aqueduct (ATVA) as a potential radiographic marker for Menière’s disease endotypes. The key finding was that PCCT enabled direct, reader-measured ATVA quantification (mean ATVA reported) and allowed additional vestibular aqueduct morphometric parameters to be assessed beyond what conventional CT resolution typically permits. This is significant because it may improve patient-specific phenotyping for Menière’s disease by replacing proxy-based ATVA measurements with direct visualization.

Van den Kerkhof F, Boomgaert L, Cockmartin L et al. · Insights into imaging · (2026) · View on PubMed ↗ · Free PDF ↗

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Cardiac electrophysiology substrate imaging with photon-counting CT

Quantification of Atrial Fibrillation-Related Imaging Markers Using Spectral Photon-Counting Computed Tomography.

This study used spectral photon-counting CT to quantify atrial fibrillation (AF)-related structural imaging markers in 65 AF patients versus 65 controls by analyzing the interatrial septum (IAS) along the anterior internodal bundle and the sinoatrial (SA) node and its vascular supply. The key finding was that PCCT enabled quantitative assessment of IAS fibrosis (scored 1–4) and tissue density measures (IAS and SA-node density) to characterize AF-associated conduction-system alterations compared with sinus-rhythm controls. These results suggest spectral PCCT could improve noninvasive identification of AF substrate by directly quantifying septal and SA-node structural changes.

Bilgeri V, Spitaler P, Kindl B et al. · Heart rhythm · (2026) · View on PubMed ↗

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Airway device sizing/placement and neonatal imaging with photon-counting CT

Computed tomography of three smaller-sized supraglottic airway device prototypes in stillborn low-birth-weight neonates.

The study evaluated three smaller-sized supraglottic airway device prototypes—including the smallest commercial i-gel size 1.0 and Neo i-gel prototypes sizes 0.65, 0.75, and 0.85—in stillborn low-birth-weight neonates (>500 g) using photon-counting CT to assess anatomical placement. Photon-counting CT was used to quantify device positioning relative to perilaryngeal landmarks and effects on adjacent structures across the different prototype sizes. This work supports the feasibility of using PCCT for optimizing airway device sizing and placement in very small neonates where clinical options are limited.

Dempsey T, Brismar TB, Svensson-Marcial A et al. · British journal of anaesthesia · (2026) · View on PubMed ↗

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Quantitative bone microstructure and musculoskeletal imaging with photon-counting CT

Assessment of trabecular microstructure using photon-counting CT: Influence of dose, spatial resolution and reconstruction algorithms.

This experimental study assessed trabecular microstructure metrics (BMD, BV/TV, and trabecular separation Tb.Sp) from photon-counting CT in seven excised human vertebral bodies embedded in polymethylmethacrylate, systematically varying radiation dose, spatial resolution, noise, and reconstruction algorithms (FBP vs iterative QIR3) on a Naeotom Alpha (Siemens Healthineers) PCCT scanner. The key finding was that measured trabecular microstructure outcomes were significantly influenced by dose level, spatial resolution, and reconstruction method. Scientifically, it provides practical guidance for optimizing PCCT acquisition and reconstruction to enable reliable quantitative central-skeleton microstructural assessment.

Peña JA, Thomsen F, Damm T et al. · Bone · (2026) · View on PubMed ↗

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Generated automatically on August 29, 2026. Covers PubMed articles published August 22, 2026 – August 29, 2026. Summaries are AI-generated; always consult the original publication for clinical or research decisions.