What’s New in Photon Counting CT?

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

Overview

Across this week’s set of studies and reviews, a dominant theme is the expanding role of spectral/photon-counting imaging to extract more than anatomy—moving toward quantitative tissue characterization and improved diagnostic performance. Multiple papers focus on photon-counting CT (PCCT) capabilities: from enabling detection and characterization of spinal arteriovenous fistulas with improved contrast-to-noise, to enhancing late iodine enhancement myocardial scar imaging where spectral analysis and reconstruction choices materially affect image quality. In parallel, quantitative PCCT methods (e.g., voxelwise effective atomic number and electron density) and physics work on higher-dimensional material decomposition show how spectral information can be leveraged to reduce uncertainty and improve downstream clinical tasks.

A second theme is translation toward patient-relevant decision-making in both oncology and radiotherapy. In multiple myeloma, ultra-high-resolution dual-source PCCT with low-keV virtual monoenergetic images supports expanded characterization of skeletal pathophysiology patterns for better whole-body assessment and risk stratification. For proton therapy, fundamental limits and feasibility analyses indicate that increasing the dimensionality of PCCT-based material decomposition can improve proton stopping power ratio and range estimation—directly targeting range uncertainty and margin reduction.

Finally, the digest also includes progress beyond CT: an AI-driven, radiation-free MRI feasibility study demonstrates accelerated 3D bone imaging using inversion recovery prepared ultra-short echo time sequences with supervised denoising. Together, these works highlight a broader trend in medical imaging toward faster acquisition, smarter reconstruction, and more quantitative outputs—whether via spectral CT or AI-accelerated MRI.

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Photon-counting CT (PCCT) for vascular and structural pathology

Utility of Photon Counting Detector CT Angiography for Detecting Spinal Arteriovenous Fistulas.

This retrospective two-institution clinical case series studied photon-counting detector CT angiography in eight patients with suspected spinal arteriovenous fistulas. The key finding was that photon-counting spinal CT angiography enabled detection and characterization of spinal arteriovenous fistulas using the technique’s spectral sensitivity and improved contrast-to-noise ratio. This supports photon-counting CT angiography as a promising, potentially more informative imaging option for a treatable cause of myelopathy.

Madhavan AA, Bathla G, Hauck EF et al. · AJNR. American journal of neuroradiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Photon-counting CT (PCCT) for musculoskeletal oncology (multiple myeloma)

Ultra-High-Resolution Dual-Source Photon-Counting CT for Expanded Characterization of Pathophysiological Imaging Patterns in Multiple Myeloma.

This retrospective study evaluated dual-source photon-counting CT (DS-PCCT) in 84 patients with multiple myeloma (53 therapy-naïve and 31 with precursor conditions) at initial diagnosis. The key finding was that ultra-high-resolution DS-PCCT using low-keV virtual monoenergetic images (VMI) and attenuation characteristics of soft tissue and fat enabled expanded characterization of axial and appendicular skeletal pathophysiological imaging patterns. This could improve whole-body assessment and risk stratification in multiple myeloma by leveraging spectral and spatial advantages of photon-counting CT.

Heidemeier A, Huflage H, Rasche L et al. · Investigative radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Photon-counting CT (PCCT) quantitative material characterization (Zeff, electron density, decomposition)

Power law spectral photon-counting CT for quantitative effective atomic number and electron density imaging.

This study developed and evaluated a scanner-specific power-law spectral photon-counting CT method to generate voxelwise effective atomic number (Zeff) and electron density (ρe) images on a commercial spectral photon-counting CT system. The key finding was that fitting a power-law model of the X-ray attenuation coefficient to NIST cross sections (Z=6–21 across 7–115 keV) enabled quantitative Zeff and ρe imaging, demonstrated using a QRM spectral-CT phantom with soft-tissue-equivalent, hydroxyapatite, and iodine inserts. This is significant for tissue characterization and quantitative material differentiation in heterogeneous samples using spectral photon-counting CT.

Alzaabi M, Behouch A, Tariq B et al. · Physics in medicine and biology · (2026) · View on PubMed ↗ · Free PDF ↗

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Photon-counting CT (PCCT) physics for proton therapy planning (SPR/range estimation)

Optimal dimensionality and fundamental limits of proton stopping power estimation with photon-counting CT material decomposition.

This physics study assessed fundamental limits and optimal dimensionality for estimating proton stopping power ratio (SPR) and range from photon-counting CT (PCCT) using photon-counting CT material decomposition. The key finding was that increasing the dimensionality of material decomposition with PCCT energy measurements can improve SPR and range estimation accuracy, with the work quantifying fundamental estimation limits and feasibility for higher-dimensional approaches relevant to proton treatment planning. This is clinically significant because more accurate SPR/range estimation can reduce range uncertainty and margins in proton therapy.

Larsson K, Näsmark T, Andersson J et al. · Physics in medicine and biology · (2026) · View on PubMed ↗ · Free PDF ↗

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Photon-counting CT (PCCT) cardiac imaging (myocardial scar and late iodine enhancement)

Image-quality optimization for late iodine enhancement with photon-counting CT: impact of spectral analysis and reconstruction parameters.

This single-center retrospective study evaluated photon-counting detector CT (PCD-CT) for late iodine enhancement (LIE) myocardial scar imaging in 74 patients. The key finding was that LIE image quality (notably contrast-to-noise ratio) was significantly influenced by spectral analysis and reconstruction parameter choices, including different reconstruction kernels and slice thicknesses. This is clinically important because optimizing these parameters may overcome low CNR limitations and expand the clinical utility of LIE for myocardial scar identification.

Bruno E, Palmisano A, Pisu F et al. · La Radiologia medica · (2026) · View on PubMed ↗

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Cardiac CT angiography (CCTA) clinical practice and guidelines

[Computed tomography in cardiology: its necessity and developments].

This narrative review discussed the necessity and developments of computed tomography in cardiology, focusing on the role of cardiac CT angiography (CCTA) in clinical practice. The key finding was that CCTA has become a central guideline-supported noninvasive modality for ruling out coronary artery disease in low-to-intermediate pretest probability patients and for rapid exclusion in selected acute/emergency settings, while also enabling characterization of coronary atherosclerosis beyond luminal stenosis. This is significant because it consolidates current evidence and clinical workflow positioning of CCTA as both a diagnostic and tissue/plaque characterization tool.

Breitbart P, Giokoglu E, Yikit E et al. · Innere Medizin (Heidelberg, Germany) · (2026) · View on PubMed ↗ · Free PDF ↗

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AI-accelerated MRI for bone imaging (radiation-free)

Fast MRI of bones in the knee - An AI-driven reconstruction approach for adiabatic inversion recovery prepared ultra-short echo time sequences.

This feasibility study investigated an AI-driven reconstruction method for fast MRI of knee bone using inversion recovery prepared ultra-short echo time (IR-UTE) sequences in eight healthy subjects. The key finding was that a supervised denoising convolutional neural network (DnCNN), trained on undersampled 3D radial IR-UTE data acquired with Pulseq, enabled accelerated 3D bone imaging with improved signal-to-noise performance using CG-SENSE reconstruction. This is scientifically significant because it advances radiation-free bone MRI by reducing acquisition time while preserving bone visualization quality.

Nunn PH, Huflage H, Grunz JP et al. · Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB) · (2026) · View on PubMed ↗ · Free PDF ↗

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