Psychic surgery is a procedure performed by self-styled psychic doctors or psychic surgeons, chiefly in the Philippines and in Brazil. Practitioners claim that it involves the extraction of " tumors" or other presumed pathological obects ( pus, bones, etc.) from the patient's body through a bloody but painless and invisible " incision ", often made with bare hands and without the use of antiseptics or anesthetics. Scientists, traditional medical doctors and stage magicians generally dismiss such practices as mere sleight-of-hand tricks, where the psychic doctor simply produces concealed blood and parts that he had suitably hidden in advance.