Purpose: To assess inter- and intraobserver reproducibility of DCE-MRI measurements and possible differences between two directly adjacent slices.
Materials And Methods: DCE-MRI measurements of 30 patients with histologically proven rectal carcinoma were performed on a 1.5 Tesla (T) MR system during intravenous contrast agent application before and after neoadjuvant radiochemotherapy with two directly adjacent slices used for calculation per patient. Images were analyzed semiquantitatively (parameters TTP and MITR) and quantitatively using the Brix compartment model (parameters kep and A) by two different observers and at two different time points. The concordance correlation coefficient was calculated for every parameter in intra-/interobserver comparison and slice comparison.
Results: Median relative differences below 10% for all parameters and high values of the concordance correlation coefficient (CCC) were found for most pharmacokinetic parameters in inter-/intraobserver comparison and slice comparison, with the exception of the parameter A before therapy in intra-/ interobserver comparison (CCC: 0.315/0.452) and kep before therapy in intraobserver comparison (CCC: 0.362).
Conclusion: Our results indicate good inter- and intraobserver reproducibility for most pharmacokinetic parameters and for the two adjacent slices measured. However, as there were some parameters that demonstrated poor correlation, testing for reproducibility and a multiobserver approach might be considered whenever using pharmacokinetic parameters as biomarkers.
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http://dx.doi.org/10.1002/jmri.24385 | DOI Listing |
Previously we reported color matches measured in young adults using a newly developed multi-wavelength LED-based visual trichromator with which we estimated their individual L-, M- and S-cone spectral sensitivities. Here, we extend those measurements to include 70 additional observers aged between 8 to 80 years. As in our previous work, a series of color matching measurements were made to a reference white.
View Article and Find Full Text PDFInt J Gen Med
January 2025
School of Biomedical Engineering & State Key Laboratory of Advanced Medical Materials and Devices, ShanghaiTech University, Shanghai, People's Republic of China.
Purpose: Conventional brain MRI protocols are time-consuming, which can lead to patient discomfort and inefficiency in clinical settings. This study aims to assess the feasibility of using artificial intelligence-assisted compressed sensing (ACS) to reduce brain MRI scan time while maintaining image quality and diagnostic accuracy compared to a conventional imaging protocol.
Patients And Methods: Seventy patients from the department of neurology underwent brain MRI scans using both conventional and ACS protocols, including axial and sagittal T2-weighted fast spin-echo sequences and T2-fluid attenuated inversion recovery (FLAIR) sequence.
Q J Nucl Med Mol Imaging
January 2025
Section of Nuclear Medicine and Diagnostic Imaging, International Atomic Energy Agency, Vienna, Austria.
Background: One can assess cortical defects on the early images of [99mTc]Tc-MAG3 renography. We aimed to assess interobserver and intraobserver reproducibility for detecting renal cortical defects using [99mTc]Tc-MAG3 for adults and children; identify causes for poor inter- and intraobserver reproducibility and to assess the effect of the kidney to background ratio (KTBR) on reproducibility.
Methods: One hundred adult and 200 pediatric renograms were included.
Diagn Interv Imaging
January 2025
UFR Santé INSERM U1096, Rouen 76183, France; Department of Radiology and Medical Imaging (Cardiac Imaging Unit), CHU de Rouen Normandie, Hôpital Charles Nicolle, University of Rouen Normandie, Rouen 76000, France. Electronic address:
Purpose: The purpose of this study was to determine the normal variations of myocardial T1, T2, and T2* relaxation times on cardiac MRI obtained at 1.5 T in healthy, sex-balanced volunteers aged between 18 and 69 years.
Material And Methods: A total of 172 healthy volunteers were recruited prospectively.
Sensors (Basel)
January 2025
Department of Biomedical Engineering, Price Faculty of Engineering, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
Goal: Current methodologies for assessing cerebral compliance using pressure sensor technologies are prone to errors and issues with inter- and intra-observer consistency. RAP, a metric for measuring intracranial compensatory reserve (and therefore compliance), holds promise. It is derived using the moving correlation between intracranial pressure (ICP) and the pulse amplitude of ICP (AMP).
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