Photon-counting Detector CT for Liver Fat Quantification: Validation across Protocols in Metabolic Dysfunction–associated Steatotic Liver Disease

Radiology, Journal Year: 2024, Volume and Issue: 312(3)

Published: Sept. 1, 2024

Background Traditional energy-integrating detector CT has limited utility in accurately quantifying liver fat due to protocol-induced value shifts, but this limitation can be addressed by using photon-counting (PCD) CT, which allows for a standardized value. Purpose To develop and validate universal MRI conversion formula enhance quantification accuracy across various PCD protocols relative proton density fraction (PDFF). Materials Methods In prospective study, the feasibility of was evaluated phantoms with nominal fractions. Five hundred asymptomatic participants 157 suspected metabolic dysfunction-associated steatotic disease (MASLD) were enrolled between September 2023 March 2024. Participants randomly assigned six groups different regarding tube voltage (90, 120, or 140 kVp) radiation dose (standard low). Of 120-kVp standard-dose group, 51% (53 104) designated as training cohort, rest group serving validation cohort. A derived from cohort estimate CT-derived (CTFF). CTFF agreement PDFF its error subcohorts stratified voltage, dose, body mass index, MASLD The factors influencing further evaluated. Results phantoms, showed excellent (intraclass correlation coefficient, 0.98; mean bias, 0.2%). total 412 122 included. follows: (%) = -0.58 · (HU) + 43.1. Across all comparisons, demonstrated (mean bias values < 1%). not influenced PDFF. Agreement also found -0.2%). Conclusion Standardized robust remarkable may serve precise alternative quantification. © RSNA, 2024

Language: Английский

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Voxelwise characterization of noise for a clinical photon-counting CT scanner with a model-based iterative reconstruction algorithm

European Radiology Experimental, Journal Year: 2025, Volume and Issue: 9(1)

Published: Jan. 2, 2025

Abstract Background Photon-counting detector (PCD) technology has the potential to reduce noise in computed tomography (CT). This study aimed carry out a voxelwise characterization for clinical PCD-CT scanner with model-based iterative reconstruction algorithm (QIR). Methods Forty repeated axial acquisitions (tube voltage 120 kV, tube load 200 mAs, slice thickness 0.4 mm) of homogeneous water phantom and CTP404 module (Catphan-504) were performed. Water also performed on conventional energy-integrating (EID) sinogram/image-based algorithm, using similar acquisition/reconstruction parameters. For smooth/sharp kernels, filtered back projection (FBP)- iterative-reconstructed images obtained. Noise maps, non-uniformity index (NUI) image histograms, power spectrum (NPS) curves computed. Results FBP-reconstructed phantom, mean was (smooth/sharp kernel) 11.7 HU/51.1 HU 18.3 HU/80.1 PCD-scanner EID-scanner, respectively, NUI values less than half those EID-scanner. Percentage reduction increased increasing power, up 57.7%/72.5% 56.3%/70.1% respectively. PCD-scanner, FBP- QIR-reconstructed featured an almost Gaussian distribution values, whose shape did not appreciably vary power. maps showed 15.7%/9.2%. limited low-frequency shift NPS peak frequency. Conclusion allowed reducing while improving its spatial uniformity. QIR decreases without modifying histogram shape, partly preserving texture. Relevance statement corroborates capability photon-counting CT imaging uniformity yielding radiation exposure, though this needs be assessed more detail. Key Points First technology. improve values. In CT, (QIR) allows decreasing effectively noise. is done limiting Graphical

Language: Английский

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Evaluation of Photon-Counting CT for Spectral Imaging in Cardiovascular Applications: Impact of Lumen Size, Dose, and Patient Habitus

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

This study evaluates the performance of a clinical dual-source photon-counting computed tomography (PCCT) system in quantifying iodine within calcified vessels, using 3D- printed phantoms with vascular-like structures lined calcium. Parameters assessed include lumen diameters (4, 6, 8, 10, and 12 mm), phantom sizes (S: 20×20 cm, M: 25×25 L: 30×40 XL: 40×50 representing 99th percentile US patient sizes), concentrations (2, 5, 10 mg/mL). Scans were performed at radiation dose levels 15, 20 mGy to systematically evaluate quantification accuracy spectral imaging performance. The results indicate that for ≥6 mm, remains stable across all sizes, deviations consistently below 0.6 mg/mL. Whereas, 4 mm lumens, stability is observed primarily smaller medium phantoms, highlighting influence size on accuracy. Virtual Monoenergetic Imaging (VMI) 70 keV showed larger lumens (≥6 mm) variations 13 ± 2 HU conditions, while remained small phantoms. These findings highlight diameter, size, optimizing PCCT protocols imaging. Importantly, demonstrates delivers highly accurate nearly entire range U.S.. PCCT's potential enhance vascular applications, surpassing conventional or Dual Energy CT.

Language: Английский

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Use of photon-counting CT and three-dimensional printing for an intra-thoracic retained ballistic fragment in a 9-year-old

Pediatric Radiology, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 17, 2025

Language: Английский

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Dual-Energy and Photon-Counting Computed Tomography in Vascular Applications—Technical Background and Post-Processing Techniques

Diagnostics, Journal Year: 2024, Volume and Issue: 14(12), P. 1223 - 1223

Published: June 11, 2024

The field of computed tomography (CT), which is a basic diagnostic tool in clinical practice, has recently undergone rapid technological advances. These include the evolution dual-energy CT (DECT) and development photon-counting (PCCT). DECT enables acquisition images at two different energy spectra, allows for differentiation certain materials, mainly calcium iodine. PCCT recent technology that scanner to quantify each photon gathered by detector. This method gives possibility decrease radiation dose increase spatial temporal resolutions scans. Both these techniques have found wide range applications radiology, including vascular studies. In this narrative review, authors present principles PCCT, outline their advantages drawbacks, briefly discuss application methods radiology.

Language: Английский

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Photon-Counting Computed Tomomgraphy: Experience in Musculoskeletal Imaging

Korean Journal of Radiology, Journal Year: 2024, Volume and Issue: 25(7), P. 662 - 662

Published: Jan. 1, 2024

Since the emergence of first photon-counting computed tomography (PCCT) system in late 2021, its advantages and a wide range applications all fields radiology have been demonstrated. Compared to standard energy-integrating detector-CT, PCCT allows for superior geometric dose efficiency every examination. While this aspect by itself is groundbreaking, do not stop there. facilitates an unprecedented combination ultra-high-resolution imaging without penalty or field-of-view restrictions, detector-based elimination electronic noise, ubiquitous multi-energy spectral information. Considering high demands orthopedic visualization minuscule details while simultaneously covering large portions skeletal soft tissue anatomy, no subspecialty may benefit more from novel detector technology than musculoskeletal radiology. Deeply rooted experimental clinical research, review article aims provide introduction cosmos PCCT, explain technical basics, highlight most promising patient care, also mentioning current limitations that need be overcome.

Language: Английский

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Accuracy of Ultralow-Dose Photon-counting CT in the Detection of Lung Changes after Lung Transplant

Radiology, Journal Year: 2024, Volume and Issue: 312(3)

Published: Sept. 1, 2024

Background Data on the diagnostic accuracy of ultralow-dose (ULD) CT protocols for periodic surveillance in recipients lung transplant are lacking. Purpose To assess potential radiation dose reduction using ULD photon-counting (PCT) to detect abnormalities during repeat follow-up. Materials and Methods Consecutive adult undergoing same-day standard-of-care low-dose (LD) PCT from March 2023 May were prospectively included. The performed with two target effective doses comprising 20% (hereafter, ULD1) 10% ULD2) standard LD protocol. 1-mm reconstructions reviewed by three readers. Subjective image quality, visibility certain anatomic structures (using a five-point Likert scale), presence independently assessed. χ

Language: Английский

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Optimization of Low‐Contrast Detectability in Abdominal Imaging: A Comparative Analysis of PCCT, DECT, and SECT Systems

Medical Physics, Journal Year: 2025, Volume and Issue: 52(5), P. 2832 - 2844

Published: March 3, 2025

Abstract Background Clear representation of anatomy is essential in the assessment pathology computed tomography (CT). With introduction photon‐counting CT (PCCT) and more advanced iterative reconstruction (IR) algorithms into clinical practice, there potential to improve low‐contrast detectability protocols. As such, it necessary perform task‐based assessments optimize protocols compare image quality between PCCT energy‐integrating CT, like dual‐energy (DECT) single‐energy (SECT). Purpose This work aimed assess abdominal used PCCT, DECT, SECT, using both model human observers. Methods Data were acquired with standard resolution scan mode on a (NAEOTOM Alpha, Siemens Healthineers, Forchheim, Germany) DECT/SECT (SOMATOM Force, Germany). Detectability was investigated CTP 515 module Catphan 600 phantom, which surrounded by fat annulus simulate an abdomen resulted water equivalent diameter 298 mm. Supra‐slice contrast rods nominal 1.0% diameters 4, 6, 9, 15 mm used. Factory adjusted acquire images various tube potentials (70, 90, 120, 140 kV PCCT; 70/150Sn 80/150Sn DECT; 100 120 SECT), virtual monoenergetic (VMI) energy levels (40 keV DECT), doses (5, 10 mGy DECT IR settings (Br40 kernel, no quantum (QIR) QIR 1 4 modeled (ADMIRE) level 3 SECT). Mixed (linear blending at two voltages) also reconstructed. The noise power spectrum task transfer function each protocol quantified; index for determined in‐house implementations observers (non‐prewhitening matched filters internal noise, NPWI, eye filter NPWEI) (in‐house four‐alternative forced choice, scoring 95% confidence intervals). Results show that minimized VMI corresponding applied spectrum's mean 70 80 pairs, respectively, DECT. respect observer calculations, normalized root‐mean‐square error NPWI NPWEI 5% 12%, respectively. improves detectability. Additionally, can be increasing strength when reducing dose. Not only does outperform VMI, but outperforms mixed imaging improving Conclusions Low‐contrast optimized appropriate selected minimize noise. may allow dose reduction compared SECT. non‐prewhitening better quantified without inclusion filter.

Language: Английский

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A methodology for incorporating a photon‐counting CT system into routine clinical use

Journal of Applied Clinical Medical Physics, Journal Year: 2023, Volume and Issue: 24(8)

Published: June 30, 2023

Abstract Photon‐counting computed tomography (PCCT) systems are increasingly available in the U.S. following Food and Drug Administration (FDA) approval of first clinical PCCT system Fall 2021. Consequently, there will be a need to incorporate PCCTs into existing fleets traditional CT systems. The commissioning process was devised by evaluating degree agreement between performance that established A (Siemens NAEOTOM Alpha) evaluated using American College Radiology(ACR) phantom (Gammex 464). scanned on 3rd Generation EID Force) at three dose levels. Images were reconstructed across range reconstruction kernels Iterative Reconstruction (IR) strengths. Two image quality metrics—spatial resolution noise texture—were calculated AAPM TG233 software (imQuest), as well metric achieve target magnitude 10 HU. For each pair EID‐PCCT kernel/IR strengths, difference metrics calculated, weighted, multiplied over all determine concordance IR characterized comparing relative texture reference function strength for system. In general, kernel “sharpness” increased system, spatial resolution, frequency, increased. given kernel, showed higher compared standard mode. implementation better preserved strengths EID, demonstrated respective 20 7% shifts from “Off” “Max.” Overall, closest match identified with 1 step 1–2 steps. Substantial reduction potential up 70% found when targeting constant magnitude.

Language: Английский

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Consistency of spectral results in cardiac dual-source photon-counting CT

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Sept. 9, 2023

We evaluate stability of spectral results at different heart rates, acquisition modes, and cardiac phases in first-generation clinical dual-source photon-counting CT (PCCT). A motion simulator with a coronary stenosis mimicking 50% eccentric calcium plaque was scanned five rates (0, 60-100 bpm) the three available scan modes (high pitch prospectively ECG-triggered spiral, axial, retrospectively ECG-gated spiral). Subsequently, full width half max (FWHM) stenosis, Dice score (DSC) for stenosed region, eccentricity non-stenosed region were calculated virtual monoenergetic images (VMI) 50, 70, 150 keV iodine density maps both diastole systole. FWHM averaged differences - 0.20, 0.28, 0.15 mm relative to static VMI across parameters high spiral scans, respectively. Additionally, there no effect rate mode on (p-values < 0.001). DSC demonstrated similarity among standard deviations 0.08, 0.09, 0.11, 0.08 keV, maps, respectively, insignificant 0.01). Similarly, illustrated small each result. Consistency phase demonstrates added benefit from PCCT further increase confidence quantification advance cardiovascular diagnostics.

Language: Английский

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