Abstract: The surgical probe according to the invention includes a collimator, made of lead or a high Z, atomic number metal; a scintillating crystal sensitive to gamma ray having an energy in the range from 30 KeV and 1 MeV; a light guide system; a photomultiplier; and electronics capable of integrating and converting analog signals to digital signals. The probe can be used in either intracavitary mode, or in laparoscopic mode, by putting the probe in a specific trocar. The apparatus may automatically subtract the background; and may provide visualization on a monitor. The probe can also include a flexible tip, in order to enlarge the field of view which the probe can be used to examine.