What’s New in Photon Counting CT?

September 17, 2026 · 2 articles · 2 research themes · covering September 10, 2026 – September 17, 2026

Overview

Across these studies, photon-counting detector CT (PCD-CT) is shown to be both quantitatively sensitive to acquisition parameters and clinically valuable for reducing patient exposure. In the physics/protocol work, X-ray tube voltage (kV) continues to measurably influence virtual monoenergetic image (VMI) CT values and contrast-to-noise ratio (CNR) in routine PCD-CT, even when using VMI. The implication is that kV is not fully “washed out” by VMI reconstruction; instead, optimal kV settings depend on the chosen VMI energy and the imaging configuration, supporting careful protocol selection for quantitative consistency and contrast performance.

In the clinical domain, PCD-CT myelography (PCD-CTM) for spontaneous intracranial hypotension demonstrates a practical benefit: substantially lower dose-length product (DLP) compared with energy-integrating detector CT myelography (EID-CTM), while maintaining diagnostic capability to detect cerebrospinal fluid–venous fistulas (CVFs). Together, the papers suggest that PCD-CT enables improved dose efficiency, but that achieving consistent image quality and quantitative reliability still requires thoughtful parameter optimization (including kV) tailored to the specific VMI and patient/workflow context.

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PCD-CT Protocol Optimization (kV, VMI, CNR)

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 study evaluated how X-ray tube voltage (kV) influences virtual monoenergetic image (VMI) CT values and contrast-to-noise ratio (CNR) in routine clinical photon-counting detector CT (PCD-CT) across multiple tissue types, VMI keV levels, kV settings, and phantom sizes. The key finding was that VMI CT values and CNR still show measurable kV dependence in PCD-CT, and specific kV settings provide optimal CNR for a given VMI energy and phantom configuration rather than kV being fully irrelevant. Clinically, this indicates that protocol kV selection remains important for quantitative consistency and image quality when using PCD-CT VMI for cross-scan comparisons and optimized contrast performance.

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

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Radiation Dose Reduction in CT (Dose-Length Product, Optimization)

Photon-Counting Detector vs Energy-Integrating Detector CT Myelography for Detecting CSF-Venous Fistulas in Spontaneous Intracranial Hypotension: Substantially Lower Radiation Dose.

This retrospective single-center cohort study compared photon-counting detector CT myelography (PCD-CTM) versus energy-integrating detector CT myelography (EID-CTM) for detecting cerebrospinal fluid–venous fistulas (CVFs) in patients with spontaneous intracranial hypotension (SIH), including 603 examinations (470 EID-CTM, 133 PCD-CTM) from 2020–2025. The key finding was that PCD-CTM achieved substantially lower session dose-length product (DLP) than EID-CTM while maintaining the ability to detect CVFs. Scientifically and clinically, the results support adopting PCD-CTM to reduce radiation exposure in SIH workups without sacrificing diagnostic performance for CVF detection.

Christensen S, Kranz PG, Malinzak MD et al. · AJNR. American journal of neuroradiology · (2026) · 1 citations · View on PubMed ↗ · Free PDF ↗

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Generated automatically on September 17, 2026. Covers PubMed articles published September 10, 2026 – September 17, 2026. Summaries are AI-generated; always consult the original publication for clinical or research decisions.