Microautoradiography of gamma-emitters: interest of latensification process

Two techniques of microautoradiography were compared in order to assess their respective values to detect gamma-emitters usually used in nuclear medicine. Grain density microautoradiography (GD MARG) and track microautoradiography (T MARG) were performed on lymphocytes labeled with 99mTc, whose conversion electrons are able to provide a signal in nuclear emulsion. Microautoradiographs are presented, that clearly demonstrate the higher sensitivity, specificity and resolution obtained by T MARG. This technique seems particularly adapted to assess the distribution of gamma-emitters in cells and tissues.