In vivo neuroreceptor imaging by SPECT in migraine.

In vivo imaging of neuroreceptor ligand binding in the human brain is a young discipline. In migraine patients only few studies on dopamine D2 receptor binding have been reported. Many potentially useful radiolabeled receptor ligands for SPECT investigations in humans are currently being treated in animal models. There are no reports on development of radiolabeled, specific 5HT1D receptor ligands, which would be of considerable interest in studies of migraine patients. The radiochemistry of receptor ligand development for SPECT is complex and expensive. However, once a suitable radiolabeled ligand has been developed, e.g. labeled with I-123 with a fairly long decay ratio, it can be made widely accessible to nuclear medical units. SPECT might even prove to be as powerful a tool as PET for quantification of neuroreceptor binding profiles. Quantification, though, is not a trivial problem and there is still a need for development of kinetic models that can be applied in the clinical setting, particularly for studies of acute conditions like a migraine attack.