Volume Rendering of a contrast enhanced CT angiography of the supraaortal vessels. Moderate stenosis at the origin of the right sided internal carotid artery.
This is a sterogram, to be viewed in crossview technique: cross your eyes, relax your vision until there are three images, then focus on the center image.
Stereoscopic cross view photos can be viewed in three dimension (3D) without special glasses. Most people can learn how to view a cross view photo in just a few minutes:
HOW TO VIEW A CROSS-EYE PAIR