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Background: 4D Flow MRI is a quantitative imaging technique to evaluate blood flow patterns; however, it is unclear how compressed sensing (CS) acceleration would impact aortic hemodynamic quantification in type B aortic dissection (TBAD). Purpose: To investigate CS‐accelerated 4D Flow MRI performance compared to GRAPP‐accelerated 4D Flow MRI (GRAPPA) to evaluate aortic hemodynamics in TBAD. Study Type: Prospective. Population: Twelve TBAD patients, two volunteers. Field Strength/Sequence: 1.5T, 3D time‐resolved cine phase‐contrast gradient echo sequence. Assessment: GRAPPA (acceleration factor [R] = 2) and two CS‐accelerated (R = 7.7 [CS7.7] and 10.2 [CS10.2]) 4D Flow MRI scans were acquired twice for interscan reproducibility assessment. Voxelwise kinetic energy (KE), peak velocity (PV), forward flow (FF), reverse flow (RF), and stasis were calculated. Plane‐based mid‐lumen flows were quantified. Imaging times were recorded. Tests: Repeated measures analysis of variance, Pearson correlation coefficients (r), intraclass correlation coefficients (ICC). P < 0.05 indicated statistical significance. Results: The KE and FF in true lumen (TL) and PV in false lumen (FL) did not show difference among three acquisition types (P = 0.818, 0.065, 0.284 respectively). The PV and stasis in TL were higher, KE, FF, and RF in FL were lower, and stasis was higher in GRAPPA compared to CS7.7 and CS10.2. The RF was lower in GRAPPA compared to CS10.2. The correlation coefficients were strong in TL (r = [0.781–0.986]), and low to strong in FL (r = [0.347–0.948]). The ICC levels demonstrated moderate to excellent interscan reproducibility (0.732–0.989). The FF and net flow in mid‐descending aorta TL were significantly different between CS7.7 and CS10.2. Conclusion: CS‐accelerated 4D Flow MRI has potential for clinical utilization with shorter scan times in TBAD. Our results suggest similar hemodynamic trends between acceleration types, but CS‐acceleration impacts KE, FF, RF, and stasis more in FL. Evidence Level: 1 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Changes in methods of reporting blood lipid levels from 1984 to 1987 were studied in 16 medical laboratories in Nebraska. The precision and accuracy of the laboratories was assessed. Fourteen of the 16 laboratories had altered the range of cholesterol values considered normal; 86 percent had lowered what they considered the upper limit of normal values. Eleven out of the 16 laboratories took patient age into account when calculating normal values in 1987, compared with only seven out of 20 in 1984. None of the laboratories took gender into account when calculating normal values in 1984, but five did so in 1987. Similar trends were seen in the reporting of related substances. Reporting procedures varied greatly, and only one laboratory used the risk level standards of the National Cholesterol Educations Program in reporting total blood cholesterol levels. Fifteen of the laboratories met NCEP standards for precision (number of decimal places) and 78 percent met NCEP standards for accuracy (within five percent of true value)., ABSTRACT: The National Cholesterol Education Program has recommended that all laboratories be consistent, precise, and accurate in the reporting and measurement of blood cholesterol levels. In a follow-up to a 1984 survey study, we assessed the changes in reporting procedures for measurements of blood lipid levels in 16 clinical laboratories in Nebraska. Using human serum reference materials of known cholesterol concentrations provided by the Centers for Disease Control, we also assessed the precision and accuracy of measurement of blood cholesterol levels in clinical laboratories in Nebraska. Fourteen of the 16 laboratories restudied in 1987 had altered the reference range for total serum cholesterol since 1984, 86% of whom lowered the upper limit of the reference range. Eleven of 16 laboratories expressed reference ranges for total serum cholesterol in terms of patient age in 1987, while only 7 of 20 did in 1984. Gender-based reference ranges increased from 0 to 5 from 1984 to 1987. Similar trends were seen in the reporting of high-density lipoprotein cholesterol and triglyceride concentrations. Reporting procedures varied greatly; only 1 laboratory used National Cholesterol Education Program risk levels for measuring total serum cholesterol levels. Fifteen laboratories met the National Cholesterol Education Program recommendation for precision (coefficient of variation,

We compared the diets of Northern Saw-whet and Long-eared Owls that roosted in the same stand of pine trees in Chain O'Lakes State Park, Illinois, in the winter of 1987-88. Through analysis of the contents of pellets that we collected at the end of the winter, we found that meadow vole (Microtus pennsylvanicus) was the most common prey item for both species of owls, followed by deer mouse (genus Peromyscus). The Saw-whet Owl also commonly preyed upon cinereus shew (Sorex cinereus). Results from this study provide insight on predator-prey relationships that may be useful for future studies on owl diet, small mammal populations, or habitat modification. [ABSTRACT FROM AUTHOR]