Magnetic Resonance Materials in Physics Biology and Medicine, Journal Year: 2024, Volume and Issue: 37(4), P. 529 - 533
Published: Sept. 11, 2024
Language: Английский
Journal of Magnetic Resonance Imaging, Journal Year: 2025, Volume and Issue: unknown
Published: April 18, 2025
ABSTRACT Background Fat and iron deposition confound measurements of R2* proton density fat fraction (PDFF), respectively, yet their combined impact on reproducibility is poorly understood. Purpose To evaluate the multi‐center, multi‐vendor PDFF quantification using a PDFF‐R2* phantom. Study Type Prospective phantom study. Phantom Commercial with simultaneously controlled combination (0%–30%) (50–600 s −1 ) values. Field Strength/Sequence 1.5‐T 3‐T, three‐dimensional ( 3D multi‐echo, spoiled‐gradient‐echo sequences, in four different centers, each vendor. Assessment Two acquisition protocols were used, optimized for moderate (Protocol 1) high R2 * 2), respectively. The was imaged multiple times at one centers to assess its stability. Statistical Tests Intraclass correlation coefficient (ICC), linear regression analysis, (RDC) repeatability (RC). Results Excellent agreement observed between vendors, field strengths, (ICC = 0.97). Stratified by protocol, excellent observed, ICC 0.96 (RDC 6.2%) Protocol 1 0.99 3.8%) 2. Increased variability increasing especially higher R2*. 0.99). strong 0.988 66.7 57.7 Higher vials or Stability tests demonstrated an 1.0 R2*, RC 0.4% 12 Data Conclusion across protocols. Reproducibility decreased slightly Evidence Level N/A. Technical Efficacy Stage 1.
Language: Английский
Citations
1
The Imaging Science Journal, Journal Year: 2025, Volume and Issue: unknown, P. 1 - 16
Published: Feb. 28, 2025
Language: Английский
Citations
0
Medical Physics, Journal Year: 2025, Volume and Issue: unknown
Published: March 13, 2025
Abstract Background Diffusion‐weighted imaging (DWI), a quantitative magnetic resonance (qMRI) technique, has the potential to aid in disease characterization and treatment response monitoring. MR‐Linacs (MRLs) enable simultaneous DWI acquisitions during radiotherapy, uniquely aiding collection of large‐scale datasets for biomarkers, such as DWI‐derived apparent diffusion coefficient (ADC), without additional patient burden. However, limited data reporting on variability MRL scanner performance characteristics, lack established clinical trial quality assurance (QA) procedures, are barriers this route biomarker validation. Purpose This study aims quantify accuracy, intra‐scanner repeatability, inter‐scanner reproducibility ADC measurements across three MRLs Australia both phantom vivo. These will inform feasibility carrying out prospective multi‐center studies investigating form core set QA procedures baselines assess sequence suitability. Methods An isotropic (at 0°C) one healthy volunteer were scanned Unity (Elekta AB, Stockholm, Sweden). Standardized (QIBA Diffusion Profile) anatomy‐specific sequences, including sequences recommended by MR‐Linac Consortium Imaging Biomarker Working Group, used image volunteer. maps generated using software (inline ADC) diffusion‐weighted ( b ‐value) images exported from console. The latter was generate commercial (offline separate comparative analysis. Performance metrics computed each sequence, variation between‐session repeatability (CV BS ) (CV), vial contoured organ. Additionally, phantoms’ known values, percentage bias (bias) calculated determine accuracy. Results Phantom‐based standardized QIBA had intra‐ CV well within guideline tolerance limits 2.2% ±3.6%, respectively. All also these tolerances, except cervix at site which showed an average +4.5%. Both accuracy all worse lower diffusivity vials measured phantom. inline offline high similarity with percent differences +0.2%. Volunteer‐based results reproducibility, brain pancreas 9.0%, however, reaching up 27.1% pelvis abdomen sequences. Conclusions demonstrated comparable reported literature, datasets. largest further investigation. suggests that qMRI techniques utilizing could be viable option future multi‐centered patient‐based Australian MRLs, phantom‐based alongside imaging.
Language: Английский
Citations
0
Magnetic Resonance in Medicine, Journal Year: 2025, Volume and Issue: unknown
Published: March 30, 2025
Abstract Purpose Quantitative MRI (qMRI) parameters such as relaxation rates and diffusion are typically temperature dependent. Therefore, using phantoms to evaluate the accuracy of qMRI pulse sequences requires accurate knowledge absolute throughout phantom. This work aims use ethylene glycol (EG) together with a multi‐echo gradient recalled echo (ME‐GRE) sequence for MR spectroscopic‐based measurement in phantoms. Methods We develop test simple spectroscopic imaging approach rapidly, automatically, accurately, precisely measure at multiple locations A series EG cubes located phantom imaged ME‐GRE over wide range temperatures (˜7°C–37°C) on scanners. The resulting images were automatically processed isolate EG. measured spectral peak spacing was calibrated fiber optic probes. precision measurements evaluated between scanners temperatures. Results can be used predict an error 0.6°C ± 0.3°C increase 0.1°C when different An automatic reconstruction without manual input is described, highlighting feasibility online implementation clinical scanner. Conclusion described easy implement provides robust, automatic,
Language: Английский
Citations
0
Journal of Magnetic Resonance Imaging, Journal Year: 2025, Volume and Issue: unknown
Published: April 18, 2025
Language: Английский
Citations
0
Cognition Technology & Work, Journal Year: 2025, Volume and Issue: unknown
Published: April 15, 2025
Language: Английский
Citations
0
Magnetic Resonance Materials in Physics Biology and Medicine, Journal Year: 2024, Volume and Issue: 37(4), P. 529 - 533
Published: Sept. 11, 2024
Language: Английский
Citations
0