Radiolabelled forms of CFT have been used in humans and animals to map the distribution of dopamine transporters in the brain. CFT was found to be particularly useful for this application as a normal fluorine atom can be substituted with the radioactive isotope 18F which is widely used in Positron emission tomography. Another radioisotope-substituted analog WIN 35,428 (where the carbon atom of either the N-methyl group, or the methyl from the 2-carbomethoxy group of CFT, has been replaced with 11C) is now more commonly used for this application, as it is quicker and easier in practice to make radiolabelled CFT by methylating nor-CFT or 2-desmethyl-CFT than by reacting methylecgonidine with parafluorophenylmagnesium bromide, and also avoids the requirement for a licence to work with the restricted precursor ecgonine.