Visipaque is an iso-osmolar contrast agent. The osmolality equal to that of blood and the sodium and calcium concentration in a ratio equivalent to blood provides high patient safety and comfort.

(V) The SI unit of electric potential.
Definition: The amount of potential energy present per unit of charge. 1 volt represents a potential of 1 joule per coulomb of charge.
The unit is named for the Italian scientist Count Alessandro Volta.

VoLumen® is a low density barium sulfate contrast agent especially designed for MDCT (multi-detector row CT) and PET/CT exams to mark the bowel. Volumen is useful for CT studies of the small bowel and mesenteric vessels.
Positive oral contrast media may limit the delineation between soft bowel tissues and the lumen and may cause artifacts. Water or methyl-cellulose transits very rapidly and may limit bowel distention and soft tissue differentiation. Volumen, similar to water appears hypodense (low Hounsfield values) on CT scan and can be used in conjunction with IV contrast. VoLumen's low density formulation is well-suited for computed tomography enterography.

A voxel is a volume element (volumetric pixel) representing a value in the three dimensional space (expressed in units of mm³), corresponding to a pixel for a given slice thickness. Voxels are frequently used in the visualization and analysis of medical data. The CT pixel intensity is proportional to the signal intensity of the appropriate voxel. Voxels are associated with CT numbers.