Among approximately 800 anatomical illustrations made by da Vinci, a great number of drawings are devoted to the cardiovascular system. Leonardo made many important discoveries. For instance, he produced the first accurate depiction of the human spine, while his notes documenting his dissection of the Florentine centenarian contain the earliest known description of cirrhosis of the liver.
Leonardo had continually studied the structure of the body in order to be able to depict the human figure properly. In 1510 in Pavia, Leonardo and Marcantonio della Torre, a professional anatomist at the University of Pavia, started dissecting corpses. This collaboration raised Leonardo's research to a higher scientific level that showed itself in the quality of his drawings. In these studies it is no longer merely a question of discovering what physically exists; instead, the interplay of bones, muscles and tendons comes to fore.