What are kidney stones?
Kidney stones (also known as Nephrolithiasis or Renal calculus) are small hard masses made up of crystals which are seen in urinary tract (Kidney, urethra and ureter). These crystals are formed by minerals and acid salts. Usually stones forms when the urine becomes concentrated as minerals get crystallized and stick together.
Kidney stone is one of the most painful condition. Kidney stones typically leave the body by passage in the urine stream, and many stones are formed and passed without causing symptoms. If stones grow to sufficient size (usually at least 3 millimeters (0.12 in)) they can cause obstruction of the ureter.
National Institute of Diabetes and Kidney Disease reports that about 1 million people in the United States are treated for kidney stones each year.