How is an 123 I ioflupane (DaTscan) performed, and what is it used for?
123 I ioflupane binds to the dopamine transporters, primarily in the basal ganglia. The scan is primarily used for the evaluation of movement disorders and in particular to differentiate true PD from other underlying disorders such as essential tremor. There is no specific patient preparation, and patients can continue to take whatever medications they are currently using other than specific medications that might block the dopamine transporters such as methylphenidate. The patient is initially given ≈15 drops of Lugol’s solution to protect the thyroid gland from 123 I uptake and associated radiation exposure. Approximately 30 to 60 minutes later, the patient is injected intravenously with 123 I ioflupane, and then SPECT imaging is initiated 3 to 4 hours after that. Scans are evaluated for radiotracer binding in the basal ganglia regions, where decreased amounts of radiotracer binding reflect presence of PD or other movement disorders