98%
921
2 minutes
20
Rationale And Objectives: Dual-source photon-counting CT (DS-PCCT) facilitates an unprecedented combination of spectral information and ultra-high resolution in whole-body imaging of multiple myeloma. This study explored the distinct characteristics of soft tissue, fat, and calcium in virtual monoenergetic images (VMI) with low photon energy, aiming to identify criteria of lesion vitality.
Materials And Methods: This retrospective study included 51 patients with multiple myeloma (67.1±10.1 y, 36 men) who underwent unenhanced whole-body DS-PCCT between October 2024 and February 2025. Three board-certified radiologists measured CT numbers within 169 osteolytic lesions (85 active) and their surrounding tissues. Differences between 40 and 70 keV were compared among active and inactive lesions. In addition, the presence of intralesional fat, calcifications, hypodense rims, homogeneity, and highlighting in color-coded virtual non-calcium maps was assessed subjectively.
Results: The attenuation difference between 40 and 70 keV VMI was markedly larger in active than inactive lesions [median 19.3 (interquartile range: 12.7-27.0) vs. -3.8 (-26.1 to 17.0) HU; P <0.001]. Homogenous density (86.3% vs. 2.4%) and conspicuous color-coding (94.9 vs. 68.7%) were more common in active myeloma, whereas intralesional fat (10.6 vs. 72.2%), calcifications (1.6% vs. 40.1%), and hypodense rims (0 vs. 37.3%) were more frequent in inactive lesions (all P <0.001). Interrater measurement reliability was excellent (intraclass correlation coefficient ≥0.95), and agreement for all qualitative criteria was high (Krippendorff α ≥0.85).
Conclusions: This investigation on whole-body DS-PCCT demonstrated a significant difference in attenuation changes from 70 to 40 keV VMI across multiple myeloma patients with a therapy response versus initial diagnosis and disease progression. Qualitative characteristics of medullary lesions, such as heterogeneity, partial recalcification, or a hypodense rim ("halo sign"), can serve as additional indicators of therapy response.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1097/RLI.0000000000001228 | DOI Listing |
Br J Radiol
September 2025
Department of Radiology, Mayo Clinic, Rochester, MN, 55905, USA.
Objectives: Determine differences in quantitative stenosis severity measurements for ultra-high-resolution (UHR) photon-counting-detector (PCD) coronary CT angiography (cCTA) relative to energy-integrating-detector (EID) cCTA in a large patient cohort.
Methods: Adult participants seen between November 2022 and March 2023 underwent a clinical dual-source EID-CT cCTA and a research dual-source PCD-CT cCTA on the same day. Percent diameter stenosis (PDS) was measured, and stenosis severity was assigned based on the PDS of the most severe lesion per patient to determine a coronary-artery-disease reporting and data system (CAD-RADS) score.
Pediatr Radiol
September 2025
Department of Radiology, University of Colorado School of Medicine/Department of Pediatric Radiology, Children's Hospital Colorado, 13123 East 16th Avenue, Box 125, Aurora, 80045, Colorado, USA.
Background: Previous studies have shown improved image quality in pediatric cardiac imaging using photon-counting detector CT (PCDCT). However, these studies did not evaluate image quality and radiation dose when utilizing the full spectral capabilities of PCDCT scanners. The full spectral capability of PCDCT scanners allows the generation of the entire array of mono-energetic reconstructions, virtual non-contrast (VNC) images, and iodine maps, which have potential advantages in evaluating complex congenital heart disease.
View Article and Find Full Text PDFEur Radiol
September 2025
Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Objectives: This study compared three-dimensional myocardial extracellular volume (ECV) quantification among single-phase and dual-phase photon-counting detector computed tomography (PCD-CT) and dual-phase energy-integrating detector computed tomography (EID-CT), using cardiac magnetic resonance (CMR) imaging as the reference.
Materials And Methods: This retrospective study included 80 patients who underwent both CMR and cardiac CT (40 patients underwent PCD-CT and 40 underwent EID-CT). Pearson correlation coefficients and intraclass correlation coefficients (ICCs) were used to evaluate the correlation and reliability of CT-ECV with CMR-ECV.
medRxiv
August 2025
Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
Purpose: To evaluate the feasibility and performance of K-edge imaging of iodine (I) and gadolinium (Gd) on a clinically available photon-counting computed tomography (PCCT) system.
Methods: A dual-source clinical PCCT scanner with four energy thresholds (20, 55, 72, 90 keV) was used to scan phantoms containing pure and mixed solutions of I and Gd across multiple concentrations (1-10 mg/mL) and radiation doses (1-8 mGy). Multi-material decomposition was performed using a calibration-based, image-domain algorithm to generate material-specific maps.
Objectives: The aim of this study was to evaluate the feasibility and reproducibility of a novel deep learning (DL)-based coronary plaque quantification tool with automatic case preparation in patients undergoing ultra-high resolution (UHR) photon-counting detector CT coronary angiography (CCTA), and to assess the influence of temporal resolution on plaque quantification.
Materials And Methods: In this retrospective single-center study, 45 patients undergoing clinically indicated UHR CCTA were included. In each scan, 2 image data sets were reconstructed: one in the dual-source mode with 66 ms temporal resolution and one simulating a single-source mode with 125 ms temporal resolution.