1. A method for vascular intervention, comprising triggering an injection of a contrast agent provided to the vicinity of a device landmark; imaging the vicinity of the device landmark for a predetermined time after the trigger; displaying an image of the vicinity of the device landmark; generating during the predetermined time after the trigger a tip-over-surrounding and a vessel-over-surrounding time-contrast curves based on the monitored vicinity of the device landmark; computing a time-dependent visibility index curve from the tip-over-surrounding and vessel-over-surrounding time-contrast curves, wherein the time-dependent visibility index curve has a maximum, thereby determining a best instant for visibility; and holding the displayed image of the vicinity of the device landmark at the best instant until the next trigger injection of the contrast agent; wherein the best instant is the time at the maximum of the time-dependent visibility index curve which is the product of the tip-over-surrounding and vessel-over-surrounding time-contrast curves; wherein the tip-over-surrounding time-contrast curve combines an average grey level on the tip and an average grey level on both sides of the tip; and wherein the vessel-over-surrounding time-contrast curve combines an average grey level on both sides of the tip with grey levels on a side of the vessel away from the tip.