http://www.fda.gov/bbs/topics/ANSWERS/2004/ANS01326.html
U.S. Food and Drug Administration
The Food and Drug Administration (FDA) has cleared for marketing an external surgical marker tag intended to minimize the likelihood of wrong-site, wrong-procedure and wrong-patient surgeries. The device is the first such surgical marker to utilize radio frequency identification (RFID) technology to mark an anatomical site for surgery. It is intended to offer additional protection for patients who are undergoing surgery.