title: Letter to the editor.
mesh_terms: D006257:Head / Q000000981:diagnostic imaging*; D006801:Humans; D007275:Injections, Intravenous; D008629:Mercury Isotopes; D008722:Methods; D011859:Radiography; D011877:Radionuclide Imaging / Q000592:standards*
chemical_list: D008629:Mercury Isotopes