Spectral performance evaluation of a second‐generation spectral detector CT

Journal of Applied Clinical Medical Physics, Год журнала: 2024, Номер 25(4)

Опубликована: Фев. 22, 2024

The aim of this study was to characterize a second-generation wide-detector dual-layer spectral computed tomography (CT) system for material quantification accuracy, acquisition parameter and patient size dependencies, tissue characterization capabilities.

Язык: Английский

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

Radiology, Год журнала: 2024, Номер 312(3)

Опубликована: Сен. 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

Язык: Английский

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

Radiology, Год журнала: 2024, Номер 312(3)

Опубликована: Сен. 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

Язык: Английский

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

Journal of Applied Clinical Medical Physics, Год журнала: 2023, Номер 24(8)

Опубликована: Июнь 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.

Язык: Английский

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

Scientific Reports, Год журнала: 2023, Номер 13(1)

Опубликована: Сен. 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.

Язык: Английский

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Material decomposition with a prototype photon-counting detector CT system: expanding a stoichiometric dual-energy CT method via energy bin optimization and K-edge imaging

Physics in Medicine and Biology, Год журнала: 2024, Номер 69(5), С. 055001 - 055001

Опубликована: Фев. 2, 2024

Abstract Objective. Computed tomography (CT) has advanced since its inception, with breakthroughs such as dual-energy CT (DECT), which extracts additional information by acquiring two sets of data at different energies. As high-flux photon-counting detectors (PCDs) become available, PCD-CT is also becoming a reality. can acquire multi-energy in single scan spectrally binning the incident x-ray beam. With this, K-edge imaging becomes possible, allowing high atomic number (high-Z) contrast materials to be distinguished and quantified. In this study, we demonstrated that DECT methods converted systems extending method Bourque et al (2014). We optimized energy bins PCD for purpose expanded capabilities employing subtraction separate high-atomic material. Approach. The decomposes into their effective ( Z eff ) electron density relative water ρ e ). model was calibrated evaluated using tissue-equivalent from RMI Gammex phantom known values elemental compositions. Theoretical were found appropriate ranges composition materials. varied slightly but considered systematic error. An ex vivo bovine tissue sample decomposed evaluate further injected gold chloride demonstrate separation agent. Main results. mean root squared percent errors on extracted 0.76% 0.72%, respectively 1.77% 1.98% DECT. types correctly identified after decomposition. Additionally, separated imaging. Significance. offers ability employ material decomposition methods, along providing

Язык: Английский

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

Diagnostics, Год журнала: 2024, Номер 14(12), С. 1223 - 1223

Опубликована: Июнь 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.

Язык: Английский

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Photon-Counting Computed Tomomgraphy: Experience in Musculoskeletal Imaging

Korean Journal of Radiology, Год журнала: 2024, Номер 25(7), С. 662 - 662

Опубликована: Янв. 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.

Язык: Английский

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Performance evaluation of single‐ and dual‐contrast spectral imaging on a photon‐counting‐detector CT

Medical Physics, Год журнала: 2024, Номер 51(11), С. 8034 - 8046

Опубликована: Сен. 5, 2024

The first commercially available photon-counting-detector CT (PCD-CT) has been introduced for clinical use. However, its spectral performance on single- and dual-contrast imaging tasks not comprehensively assessed.

Язык: 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, Год журнала: 2025, Номер 9(1)

Опубликована: Янв. 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

Язык: Английский

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