FIG 1.

cDSA with low variance among raters in MTT results. Right internal carotid arteriogram in a lateral projection shows a right frontal operculum AVM supplied by 2 anterior cortical branches of the MCA, with dominant venous drainage into the vein of Labbe. All 4 raters (A–D) chose the same image to interpret and placed ROIs on the primary feeding artery and primary draining vein, in almost the same location. E, Time-density curves for the 4 raters are largely consistent, with the exception of a slightly larger arterial ROI by rater 3 (C) encompassing an adjacent overlapping vessel, which results in a larger AUC for the arterial ROI (F). The peaks of the time-density curves are consistent, however, yielding reproducible results (median MTT of 1.73 seconds with IQR = 1.06–2.4).