Visualize vertebra density

I want to visualize the vertebra density in a 3D manner through CT images.
I need to assign pseudo color to each voxel refering to the voxel value and then visulize them by volume rendering.
I have read the basic Slicer programming tutorial but do not know how to realize my idea. Particularly I am confused in how to visualize the pseduo color of each voxel in a 3D manner properly.

Do you need something other than is already supported by the Volume Rendering module?