Movement Disorders

Question 1

What is Parkinson’s Disease?

Answer 1

-Degeneration of the substantia nigra
-Patients experience: Resting tremors, bradyskinesia, rigidity
- PET F-18 Dopa and SPECT DaT scanning is helpful in diagosis

Question 2

What are the three types of parkinsonian syndromes?

Answer 2

-Idiopathic PD
-Secondary PD (Wilson’s disease or carbon monoxide)
-Neurodegenerative syndromes

Question 3

What is a DaT scan?

Answer 3

-Dopamine transporter visualization
-Determines: Cause of tremors, lewy body from alzheimer’s, and early Dx of presynaptic parkinsonian syndromes
-Schedule II controlled substance used- Cocaine derivative

Question 4

How do you prep a patient for a DaT scan?

Answer 4

-Discontinue interfering medications
-Thyroid blocker: Lugol’s or potassium perchlorate 1 hr pre injection

Question 5

What is the protocol for a DaT scan? (Dose, inj-scan time, positioning, parameters?

Answer 5

-111-185 MBq, slow injection
- Wait three hours
- Patient supine in a head holder
-Collimator: LEHR
- Acquisition:
>3 degree steps
> 30-40 seconds per stop
>360 rotation
>1.5 million counts for optimal image
-Ensure patients know to be well hydrated and void frequently in the first 24 hours

Question 6

What are common DaT scan results?

Answer 6

-78% of patients have a positive scan
-97% of patients with a negative scan were true negatives
-Clinicians change diagnosis in 30% of patients post-DaT scan imaging and significantly change clinical management in 50-60% of patients

Question 7

Why do we image epilepsy?

Answer 7

-In medically refractory seizures that require surgery for therapy
-Localization requires EEG, MRI, and NM for evaluation
-Goal is to use non-invasive imaging to guide a surgeon before and invasive procedure
- NM role: Based on the ability to assess physiology and aid in localization of seizure focus

Question 8

What is an interictal injection?

Answer 8

-injected during normal brain function
-Site is normal, hypo-perfused, and hypo-metabolized
-Decreased rCBF and glucose metabolism
-40% positive, less sensitive, 70% temporal lobes

Question 9

What is an ictal injection?

Answer 9

• Injected during active seizure
• Site is hyper-perfused and hyper-metabolized
  -Very difficult to achieve
  -Logistics: EEG, decay, ensuring seizure of interest has occurred
  -97% positive localization

Question 10

What is a post-ictal injection?

Answer 10

-Injected immediately after seizure
-Shows areas of increased and decreased perfusion because activity is changing
-71% positive if injection is done within 5 mins of seizure