The area under a curve can be estimated by dividing it into triangles, rectangles and trapeziums. If we have a speed-time or velocity-time graph, the distance travelled can be estimated by finding ...

ROC Curves: Sensitivity and Specificity of Various Velocity Criteria Peak Systolic Velocity. As noted in Table 6, a PSV of = 155 cm/s was optimal in detecting = 30% in-stent restenosis ...