You are leaving Medscape Education
Cancel Continue
Log in to save activities Your saved activities will show here so that you can easily access them whenever you're ready. Log in here CME & Education Log in to keep track of your credits.

Table 1.  

Differential Imaging Findings in Parkinsonian Syndromes

Table 2.  

Differential Imaging Findings in Dementias

Technology Insight: Imaging Neurodegeneration in Parkinson's Disease

Authors: David J Brooks, MD, DSc, FRCP, FMedSciFaculty and Disclosures


Summary and Introduction


Currently, the clinical diagnosis of Parkinson’s disease (PD) can be problematic, particularly at the early stages of the disease when the full spectrum of symptoms and signs might not yet be manifest. In addition, the mechanisms that underlie the nonmotor complications of PD, such as dementia and depression, are poorly understood, despite the fact that these symptoms largely determine the patient’s quality of life at the end stage of the disease. This article reviews the latest advances in structural and functional imaging that have provided important insights into the structural, pathophysiological and pharmacological changes associated with PD. The contribution of inflammatory processes to the pathology of PD is discussed, as are the various possible mechanisms that lead to coexistent dementia and depression.


The definitive diagnosis of idiopathic Parkinson’s disease (PD) requires the demonstration of intracellular Lewy body inclusions via histological examination of brain tissue, which is not a viable approach in living individuals. Retrospective clinico pathological studies have shown that a clinical diagnosis of PD during life correlates with a postmortem finding of brainstem Lewy body disease in, at best, 85% of patients.[1] Atypical parkinsonian disorders, such as multiple system atrophy (MSA) and progressive supra nuclear palsy (PSP), can mimic PD, as can severe essential and dystonic tremors. Patients with early-stage disease, in which the full constellation of parkinsonian symptoms and signs are not yet manifest, can be the most difficult to diagnose. Consequently, the ability to detect or exclude loss of nigral dopaminergic neurons or striatal dopamine terminal function by use of non invasive imaging approaches would be a valuable tool that could not only help physicians to increase diagnostic specificity, but could also enable the appropriate management decisions to be made at the initial stages of the disease.

  • Print