In this March 22, 2013 photo, Dr. Pier Giulianotti, chief of minimally invasive and robotic surgery at the University of Illinois Hospital & Health Sciences System in Chicago, shows off a robotic arm of the da Vinci robot system. Surgeons say the advantages of the system include allowing them to operate sitting down, using small robotic hands with no tremor. But critics say a big increase in robot operations nationwide is due to heavy marketing and hype, and the U.S. Food and Drug Administration is looking into problems and deaths that may be linked with robotic surgery. (AP Photo/M. Spencer Green)CHICAGO (AP) — Robotic surgical operation is being performed increasingly regularly for a lot of operations. But experts say there's a lack of sturdy proof that it's any better than standard surgical operation generally — and it's usually costlier.