Figure 3

Receiver-Operating Characteristic (ROC) Analysis. ROC curves for Ischemic Extent (IE) and Segment-Intensity Response (SIR) metrics derived on the basis of end-systole (A) and end-diastole (B) BOLD images, for detecting critical stenosis (Microsphere Flow Ratio ≤2) are shown. For reference, the line of no discrimintation is also shown (dotted line). The similarity colored arrows point to the optimal operating cutodd points for each method. ROC analysis showed: for IE (ES or ED), sensitity (88% or 83%), specificity (100% or 86%)m and Area-Under-the-Curve (0.97 or 0.88); for SIR (ES or ED), sensitivity (77% or 83%), specificity (88% or 43%) and Area-Under-the-Curve (0.83 or 0.47). IE, derived using ARREAS, shows superior sensitivity and specificity compared to currently used approaches relying on the mean intensity of myocardial segments (SIR).