DatScan

DATSCAN: Brain Scintigraphy with Receptor Tracer

Parkinson’s disease is a degenerative condition of the central nervous system characterized by a slow and progressive course, resulting from the decreased production of the neurotransmitter dopamine. It typically presents with three primary symptoms: bradykinesia, rigidity, and resting tremor. The diagnosis is mainly clinical, relying on the presence of typical motor symptoms, as well as the patient’s medical and family history. However, instrumental diagnostics, such as magnetic resonance imaging (MRI) and brain scintigraphy with DATSCAN, play a crucial supportive role in the diagnostic process and in monitoring disease progression.

 What is DATSCAN and how does it work?

Brain scintigraphy with DATSCAN is an essential test for distinguishing between Parkinson’s disease and parkinsonism—syndromes that exhibit symptoms similar to Parkinson’s but do not have the same neurodegenerative basis. This non-invasive procedure is simple to perform, repeatable, and provides reliable, reproducible imaging results.

The focus of the exam is the study of specific brain regions known as the “basal ganglia.” In Parkinson’s disease, these areas are dopamine-deficient, a deficiency visible on a DATSCAN as a reduction in signal intensity, varying in degree across these regions. The amount of dopamine reduction in these areas directly correlates with the severity of typical Parkinsonian symptoms: the lower the dopamine levels, the more pronounced the symptoms. If symptoms are due to other causes unrelated to dopamine deficiency, the DATSCAN will appear normal, showing optimal signal representation within the basal ganglia.

The DATSCAN procedure involves the intravenous administration of a mildly radioactive substance, known as a tracer. The most commonly used tracer is Ioflupane, which is marked (and thus made radioactive) with an iodine-123 (123I) molecule. The injection is safe, brief (lasting only seconds), and does not cause any adverse reactions.

The tracer binds to dopamine re-uptake transporters (DAT) located on the surface of nerve endings projecting from the substantia nigra to the striatum. In cases of damage to the substantia nigra, as seen in Parkinson’s disease, fewer nerve terminals reach the striatum, resulting in a reduced number of DAT transporters. Consequently, the binding sites for Ioflupane are diminished, leading to lower radioactivity emission in these areas.

What does the DATSCAN study reveal?

This exam allows for the analysis of dopaminergic innervation within the basal ganglia and the quantification of any reduction. DATSCAN is particularly indicated for patients with a doubtful Parkinson’s disease diagnosis: a positive DATSCAN result can confirm the clinical suspicion of Parkinson’s, aiding in the differential diagnosis from other neurological conditions with similar clinical presentations. Functional imaging with DATSCAN can also detect the loss of presynaptic nigrostriatal terminals in the early stages of the disease. Repeating the exam over time enables the evaluation of disease progression.

Our facility is equipped with a state-of-the-art gamma camera and a digital PET-CT scanner, which significantly reduces the dose of radioactive substance administered to the patient and shortens examination times, while maintaining high sensitivity and spatial resolution for more precise diagnoses.

Our team of expert nuclear medicine specialists, along with skilled technical, nursing, and administrative staff, ensures a high-quality environment for achieving excellence in diagnostics in Rome. The health of our patients is our top priority!

The close collaboration between nuclear medicine doctors, various specialists, and primary care physicians ensures prompt communication regarding disease progression for accurate and timely management.

Execution Procedure of the Exam

How to Prepare for the Exam

On the day of the examination, the patient should arrive at the Nuclear Medicine department for a preliminary consultation with the Nuclear Medicine physician. During this consultation, the physician will collect the patient’s main clinical information, including the reasons for the exam, symptoms that led to its scheduling, ongoing treatments, and any previous imaging tests performed. The procedure will be explained in detail, and the patient will be asked to sign the informed consent form.

Fasting is not required for the exam.

At the discretion of the specialist, it is recommended to suspend any medications that could affect the visual and semi-quantitative assessment of receptor uptake. The suggested suspension period for interfering drugs is at least five times the drug’s biological half-life.

If the suspension of the medications listed above is not possible, this should be communicated to the Nuclear Medicine physician performing the exam.

Anti-Parkinson drugs do not need to be suspended, as they do not significantly interfere with the binding of the tracer to the DAT transporters.

At the end of the consultation, the Nuclear Medicine physician will administer the radiopharmaceutical intravenously. The patient will then wait in a “warm” waiting room for approximately 3 hours. This period is necessary for the radiopharmaceutical to distribute throughout the body and optimally deposit in the basal ganglia. After the waiting period, the patient will lie on the Gamma Camera table, and the scanning phase will begin, lasting about 30 minutes. During this time, the machine will rotate around the patient’s head to perform what is known as a brain SPECT scan.

At the end of the scanning phase, the patient will have completed the exam and can leave the Nuclear Medicine department to continue their normal activities and routines. The administration of the radiopharmaceutical does not negatively impact nervous system function.

When is the exam contraindicated?:

Confirmed or suspected pregnancy.

Inability of the patient to cooperate with the procedure (remaining still on the machine for the entire duration of the exam).

If breastfeeding, it is necessary to suspend breastfeeding for 48 hours after the administration of the tracer. On the day of the exam, avoid close contact with pregnant women and children.