Point Shear Wave Elastography for Grading Liver Fibrosis: Can the Number of Measurements Be Reduced?
Isabelle Durot1, Alireza Akhbardeh1, Jarrett Rosenberg1
1Department of Radiology, School of Medicine, Stanford University, Stanford, California, USA.
Abstract:
The aim of this study was to assess whether the number of liver point shear wave elastography (pSWE) measurements could be reduced compared with the currently recommended 10 valid measurements. Three thousand four hundred one pSWE examinations in patients with liver disease were performed with 10 consecutive valid measurements in liver segment 8. Liver fibrosis grading using published cutoff values were compared retrospectively using the median of 10 versus the first 1-9 measurements with Kendall's τ coefficient. Overall and binary (clinically significant [≥F2] versus non-significant [F0/F1]) fibrosis grading highly correlated when using 5-9 versus 10 valid measurements (τ = 0.96/0.95, p < 0.001). With the use of 5 valid measurements, a change in binary grading was observed in 87 of 3401 (2.6%) exams and only when velocities measured between 1.1 and 1.5 m/s. Therefore, using 5-9 valid measurements in pSWE of the liver results in a small portion of liver fibrosis grading misclassifications compared with use of 10 measurements and could help decrease scanning time, cost and discomfort in sonographers and patients.
Related Concept Videos
The Wave Nature of Light
Graded Potential
Graded potentials fall into two categories: depolarizing and hyperpolarizing. Depolarizing graded potentials typically occur when sodium (Na+) or...
Shear Diagram
First, a free-body diagram of the beam is drawn, representing all the external forces and internal reactions acting on the beam. One can calculate the reaction forces at each support by employing the equilibrium equations of force and moment. The vertical component...
Shearing Stress
The average shearing stress can be calculated by dividing the shear by the area of the cross-section.
Shearing Strain
Types of Aggregate Grading
Well-graded aggregates include a complete range of necessary size fractions that fit together to create a dense matrix with minimal voids, represented by a smooth, continuous gradation curve. This type of grading ensures good...


