Ioflupane (I-123)
Ioflupane (I-123) is a radiopharmaceutical for the diagnosis of Parkinson disease and its differential diagnoses: essential tremor versus tremor due to parkinsonian syndromes (idiopathic Parkinson disease, multiple system atrophy and progressive supranuclear palsy).
Characteristics
- iodine-123 is a cyclotron product
- decay by electron capture to tellurium-123
- physical half-life is 13.22 hours
- predominant energy of its gamma spectrum is 159 keV
Ioflupane is the international non-proprietary name of a phenyltropane compound, usually abbreviated to FCPIT (fluoropropyl beta-carbomethoxy-3 beta-(4-iodophenyltropane), a cocaine analog. Ioflupane has a high affinity for presynaptic dopamine transporters (DAT) which are abundant in the striatal region.
I-123 ioflupane is available worldwide and marketed under the trade name DaTSCAN.
Uses, doses and timing
- as a cyclotron product, the solution is supplied ready to inject
- the dose reference activity of I-123 ioflupane is 185 MBq (5 mCi)
- administration is intravenous
- thyroid blocking with 120 mg potassium iodide 2 hours before and 24 hours after the injection is recommended
- SPECT is typically performed 3-6 hours after injection
See also
Reduced putaminal uptake as evidenced visually by the loss of the normal comma- or crescent-shaped uptake in the striatum and the appearance of abnormal period- or oval-shaped uptake in the caudate only is supportive of a diagnosis of a parkinsonian syndrome:
