Abstract versus realistic

I do a fair amount of presentation design work in the medical field and in every deck there is the challenge of explaining the technology to a layman. The medical profession uses elaborate, highly realistic, illustrations to visualize a condition or a procedure. I actually find the other approach much more effective: highly abstract, minimalist sketches that show only what needs to be shown, and eliminate everything else. The visual needs to explain what is going on, not what something looks like.