Normal DaT (I-123 Ioflupane) scan

Case contributed by Justin G Peacock
Diagnosis almost certain

Presentation

Patient presenting with a tremor. The patient has a history of amyloid angiopathy.

Patient Data

Age: 70 years
Gender: Male
Nuclear medicine

Normal symmetric radiotracer uptake in classic comma shape through the bilateral caudate nucleus and putamen. Visually distinct from the surrounding brain parenchyma.

  • Mild T2/FLAIR subcortical and periventricular white matter hyperintense foci, likely sequela of chronic small vessel ischemic changes
  • Moderate senescent parenchymal volume loss
  • Susceptibility artifact from the right orbit partially obscures evaluation of the right frontal lobe

Case Discussion

DaT (I-123 Ioflupane) scan is the most definitive diagnostic imaging tool for Parkinsonism, identifying dopaminergic neuron loss in Parkinsonism syndrome, including parkinson disease, multisystem atrophy (MSA), progressive supranuclear palsy (PSP), corticobasilar degeneration (CBD), and diffuse Lewy body disease (DLBD). It is commonly used in distinguishing Parkinsonism tremor from other causes of tremor, such as essential tremor.

Lugol solution or sodium iodide solution is used prior to DaT scan to prevent radioiodine absorption by the thyroid gland. Many medications that interfere with ioflupane absorption, including stimulants (ephedrine, cocaine, methamphetamine, amphetamine), benztropine, fentanyl, bupropion, and phentermine need to be discontinued prior to DaT scan imaging.

The normal DaT scan findings in this case suggest a non-Parkinsonism etiology for the patient's tremor, such as essential tremor.

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.