This is a 53 year old female with complains
of left hand tremors and slowness of movements as her only presenting symptoms. The patient had a family history of Parkinson’s disease. But the patient was also already on treatment with a neuroleptic drug (Clozapine), which is also known to cause Parkinsonian symptoms.
Tc-TRODAT scan was asked for, to differentiate an idiopathic Parkinson’s disease from a drug induced Parkinsonism.
Image 1, the scan findings of this patient
showed a dopaminergic deficit in the right sided Putamen; the rest of the striatum showing a normal tracer uptake.
These findings are diagnostic of an idiopathic Parkinson’s disease.
Image 2, for reference, is how a normal TRODAT scan appears.
The case highlights the utility of Nuclear
medicine in evaluation of Parkinsonism.
While an abnormal scan would mean
Parkinsonism (either idiopathic PD or an
atypical/ Parkinson’s plus syndrome), a
normal study essentially rules out a
TRODAT scan is the only available imaging modality currently for reliably diagnosing Parkinson’s disease. In fact, it is reported that while the clinical symptoms appear after degeneration of about 50% of the neurons, the scan can be positive at an even earlier preclinical stage.