Cordotomy (or chordotomy) is a surgical procedure that disables selected pain-conducting tracts in the spinal cord, in order to achieve loss of pain and temperature perception. This procedure is commonly performed on patients experiencing severe pain due to cancer or other diseases for which there is currently no cure. Anterolateral cordotomy is effective for relieving unilateral, somatic pain while bilateral cordotomies may be required for visceral or bilateral pain.