MONICA SCHROEDER / SCIENCE PHOTO LIBRARY MONICA SCHROEDER / SCIENCE PHOTO LIBRARY
Illustration showing three types of kidney stones: Calyceal stone (top), renal pelvic stone (middle), upper ureteral stone (bottom). Kidney stones are formed when mineral salts, most often involving calcium, accumulate on the inner surfaces of the kidney. As they grow they may block the flow of urine out of the kidney, causing extreme pain.
Model release not required. Property release not required.