A system orientates and displays intra-vascular ultrasound imaging data using an acquisition processor and an image data processor. The acquisition processor acquires, during navigation of an ultrasound catheter through a vessel, for multiple individual intra-vascular ultrasound images comprising an image sequence, data representing an individual image and orientation data associated with the individual image indicating orientation of the catheter and individual image with respect to a reference position external to patient anatomy. The image data processor aligns the multiple individual intra-vascular ultrasound images with respect to the external reference position by rotating individual images of the image sequence as necessary to have substantially the same orientation with respect to the external reference position in response to the orientation data.