Once made public, the wounds were studied by a number of physicians, some hired by the Vatican as part of an independent investigation. Some claimed that the wounds were unexplainable and never seem to have become infected. Despite seeming to heal they would then reappear periodically. Alberto Caserta took X-rays of Pio's hands in 1954 and found no abnormality in the bone structure. Some critics accused Pio of faking the stigmata, for example by using carbolic acid to make the wounds. Maria De Vito (the cousin of a local pharmacist at Foggia) testified that the young Pio bought a little bottle of carbolic acid and four grams of veratrine in 1919.