What’s New in Photon Counting CT?

October 22, 2026 · 9 articles · 12 research themes · covering October 15, 2026 – October 22, 2026

Overview

Across this week’s set of studies and reviews, a dominant theme is the rapid maturation of photon-counting CT (PCCT) and related detector technologies for quantitative, biomarker-oriented imaging. Multiple works compare PCCT with energy-integrating detector CT (EIDCT) or test different PCCT acquisition/reconstruction strategies to improve measurement fidelity—ranging from coronary stenosis grading and radiation dose tradeoffs, to resolving carotid web mimics, to optimizing visualization of the carotid body. Together, these results emphasize that detector mode, reconstruction choices, and contrast phase can materially affect both diagnostic performance and the reliability of quantitative outputs.

A second major theme is “precision imaging” for disease monitoring and response assessment using CT-derived quantitative metrics. In rectal adenocarcinoma, pretreatment PCCT iodine concentration normalized to MRI-derived ADC is explored as a predictor of neoadjuvant response, suggesting a pathway toward noninvasive treatment stratification. For interstitial lung disease in inflammatory idiopathic myopathy, a feasibility study tests whether tin-filtered low-dose PCCT can preserve quantitative ILD burden measurements, supporting safer longitudinal monitoring. In parallel, a preclinical radiomics study highlights the need to account for age-associated imaging patterns and platform/reconstruction effects to make radiomics models more transferable.

Finally, several articles focus on protocol-level optimization and clinical translation. Narrative reviews address dual-energy CT pulmonary angiography (DECTPA) with structured frameworks for individualized low-iodine scanning, and modern cardiac CT’s expanding role beyond luminal stenosis for comprehensive risk stratification in stable chest pain. In neurovascular/neuroimaging, an ASFNR state-of-practice statement underscores the need to standardize and validate imaging phenotypes of chronic subdural hematoma neomembrane activity to improve recurrence-risk stratification and MMAE treatment selection—mirroring the broader push toward standardized, validated imaging biomarkers.

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Coronary CT angiography (CCTA) for stable chest pain and coronary disease risk

The evolving role of cardiac CT: Emerging technologies and clinical impact.

This narrative review assessed how cardiac computed tomography (CT)—including coronary CT angiography (CCTA)—has evolved for evaluating stable chest pain and suspected chronic coronary syndromes, and how newer CT technologies expand assessment beyond luminal stenosis. It reports that CCTA is increasingly endorsed as a first-line test in appropriately selected patients because it can exclude obstructive coronary artery disease, quantify atherosclerotic burden, support preventive therapy, and guide referral for invasive angiography. The review’s clinical significance is that modern cardiac CT can function as a comprehensive platform for coronary, myocardial, valvular, and structural heart disease risk stratification and management.

Oda S, Iima M, Yanagawa M et al. · Diagnostic and interventional imaging · (2026) · View on PubMed ↗ · Free PDF ↗

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Coronary stenosis assessment with detector technology (PCD-CT)

Impact of Photon-Counting CT Acquisition Modes on Coronary Stenosis Assessment and Radiation Dose: A Phantom and Clinical Evaluation.

This phantom-and-clinical evaluation tested how different photon-counting detector CT (PCD-CT) acquisition modes affect coronary stenosis assessment and radiation dose in coronary CT angiography (cCTA). Using a first-generation dual-source PCD-CT with acquisition modes including Flash (high-pitch spiral with prospective ECG gating), Sequence, Spiral, and retrospective ultra-high-resolution (UHR) spiral, the study compared image quality, blooming, stenosis grading accuracy, and dose. The clinical significance is that identifying the optimal PCD-CT acquisition mode can improve diagnostic performance while minimizing radiation exposure for coronary stenosis evaluation.

Stein T, Lang F, Bamberg F et al. · Zeitschrift fur medizinische Physik · (2026) · View on PubMed ↗ · Free PDF ↗

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CT imaging biomarkers for cancer treatment response (rectal adenocarcinoma)

Photon-counting computed tomography and magnetic resonance imaging in rectal cancer: reassessment of normalized iodine concentration and apparent diffusion coefficient in an expanded cohort.

This single-center retrospective study evaluated whether pretreatment photon-counting CT (PCCT) normalized iodine concentration (NIC), using MRI-derived apparent diffusion coefficient (ADC) as a within-cohort reference, predicts neoadjuvant treatment response in 63 patients with rectal adenocarcinoma. It stratified Dworak tumor regression grades 0–1 as poor response and grades 2–4 as moderate/good response and reassessed PCCT-derived NIC in relation to MRI response markers. The scientific significance is that PCCT iodine metrics—calibrated against MRI ADC—may improve noninvasive assessment of rectal cancer treatment response and potentially guide therapy selection.

Saeed S, Shahzadi I, Niehoff JH et al. · Abdominal radiology (New York) · (2026) · View on PubMed ↗ · Free PDF ↗

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Quantitative CT for interstitial lung disease (ILD) monitoring

Low-dose vs standard-dose photon-counting CT for myopathy-associated interstitial lung disease: a prospective feasibility study.

This prospective feasibility study compared standard-dose versus tin-filtered low-dose photon-counting CT (PCCT) for quantifying interstitial lung disease (ILD) burden in patients with inflammatory idiopathic myopathy (IIM-ILD), and assessed the added value of ultrathin reconstructions. Outpatients underwent two consecutive PCCT scans (LD 1.0 mm vs SD 1.0 mm reconstruction) and quantitative ILD features were extracted using ContextFlow ADVANCE Chest CT deep-learning software. The clinical significance is that it evaluates whether lower-dose PCCT can preserve quantitative ILD assessment performance, supporting safer imaging for monitoring IIM-ILD.

Zhu Z, Xu K, Pang Y et al. · European radiology · (2026) · View on PubMed ↗

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Radiomics and computational imaging (age, platform effects)

Age-associated radiomic phenotyping in mice using multi-energy photon-counting and preclinical CT: an exploratory study.

This exploratory preclinical study investigated whether CT-derived radiomic features reflect chronological age-associated imaging patterns in female C57BL/6NRj mice across three age groups (28, 88, and 99 weeks) using multi-energy photon-counting CT (PCCT) and preclinical Albira II CT. Radiomics were extracted from segmented heart, liver, and spleen and classification performance was evaluated with nested leave-one-mouse-out cross-validation while accounting for platform and reconstruction strategy. The scientific significance is that age-associated radiomic phenotyping and platform effects can be quantified, improving the reliability of radiomics-based models in longitudinal or translational mouse studies.

Castioni NA, Wängler C, Mogler C et al. · Biogerontology · (2026) · View on PubMed ↗ · Free PDF ↗

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Carotid imaging: carotid body visualization and quantification

Carotid Body Detection Rate and Size on Photon-Counting Versus Energy-Integrating Detector CT.

This retrospective single-institution study compared carotid body (CB) detection rate and size on photon-counting CT (PCCT) versus energy-integrating detector CT (EIDCT) in 48 adult patients undergoing head-and-neck CTA in both arterial and venous phases. CB detection and size measurements were analyzed with mixed-effects logistic and linear models to quantify effects of modality, phase, and laterality. The findings are clinically relevant because they inform which CT detector technology and contrast phase best optimize carotid body visualization and quantification for potential future biomarker use.

Unger RH, Arizono E, Buch K et al. · AJNR. American journal of neuroradiology · (2026) · View on PubMed ↗

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Carotid imaging: carotid web detection and differential diagnosis

Ultra-high-resolution photon-counting CT argues against a suspected bilateral carotid web: a case report.

This case report evaluated a suspected bilateral carotid web appearance in a 75-year-old woman with transient ischemic attack by comparing multiple carotid CTA examinations using different CT technologies. It contrasted an earlier dual-energy energy-integrating detector CT (EID-CT) angiogram, a stroke-protocol photon-counting detector CT (PCD-CT) angiogram at presentation, and a dedicated ultra-high-resolution photon-counting CT to determine whether the web-like finding was due to reconstruction or acquisition. The clinical significance is that ultra-high-resolution photon-counting CT can help resolve carotid web mimics and reduce misdiagnosis that could affect antithrombotic or procedural management.

Ben-David E, Bogot NR, Berrebi Y et al. · Emergency radiology · (2026) · View on PubMed ↗

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Pulmonary embolism imaging with dual-energy CT (DECTPA)

Dual-energy computed tomography pulmonary angiography for pulmonary embolism: a three-tier evidence framework to guide individualized low-iodine scanning.

This narrative review synthesized evidence (28 eligible studies from 2016–June 2026) on dual-energy CT pulmonary angiography (DECTPA) for pulmonary embolism (PE) to support individualized low-iodine scanning strategies. It organized findings into a three-tier framework—image quality, diagnostic performance, and clinical outcomes—to address heterogeneity across protocols and platforms. The significance is that a structured evidence framework can help clinicians select low-iodine DECTPA protocols that maintain diagnostic accuracy while reducing iodine load in PE imaging.

Jiang Q, Qian L · Diagnostic and interventional radiology (Ankara, Turkey) · (2026) · View on PubMed ↗ · Free PDF ↗

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Neuroimaging biomarkers for chronic subdural hematoma and recurrence risk

ASFNR Clinical State of Practice Statement on Imaging of Chronic Subdural Hematoma.

This American Society of Functional Neuroradiology (ASFNR) clinical state-of-practice statement reviewed imaging approaches for chronic subdural hematoma (cSDH) in the context of middle meningeal artery embolization (MMAE) and the need for imaging biomarkers of neomembrane activity and recurrence risk. It highlights that cSDH “imaging phenotype” (internal hematoma architecture) has not yet been standardized or validated for incorporation into randomized trials or MMAE treatment-selection algorithms. Standardized, validated imaging-phenotype definitions could improve patient stratification and reduce recurrence after MMAE by better reflecting neomembrane biology.

Ahmed S, Essibayi MA, Kakadiya J et al. · AJNR. American journal of neuroradiology · (2026) · View on PubMed ↗

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Generated automatically on October 22, 2026. Covers PubMed articles published October 15, 2026 – October 22, 2026. Summaries are AI-generated; always consult the original publication for clinical or research decisions.