Volume rendering of CT data: applications to the genitourinary tract.

A, Volume-rendered image from CT data set shows surface features of phantom. B, Volume-rendered image of CT data set of the phantom obtained by decreasing the opacity of water-density voxels, providing visualization of simulated kidneys, pennephnic fat, and intrarenal calculi. Stands (arrows) supporting kidneys obscure calculi somewhat. C, Volume-rendered CT data set after spatial editing, which provides isolation ofthe kidneys and elimination of obscuration from supporting stands.