A Review of Diagnostic Techniques for Parkinson’s Disease

Parkinson's disease is the second most common progressive neurodegenerative disorder in older people. Idiopathic Parkinson's Disease is associated with risk factors such as aging, family history, pesticide exposure, and environmental chemicals (e.g., synthetic heroin use). It is caused by a pathophysiologic loss or degeneration of dopaminergic neurons in the substantia nigra of the midbrain and the development of neuronal Lewy Bodies. Its underlying causes are unknown. Despite significant advances in neurodegenerative disease research since James Parkinson's first medical description of Parkinson's disease in 1817, these disorders continue to pose significant diagnostic and treatment challenges. A valid diagnosis at early disease stages is critical because it can help accommodate differential prognostic and disease management approaches, elucidate reliable clinicopathological relationships ideally at prodromal stages, and would make it easier to evaluate innovative treatments in clinical trials. The pursuit of early diagnosis in Parkinson's disease and atypical Parkinsonian syndromes, however, is hampered by significant clinical and pathological heterogeneity, which can affect disease presentation and progression. Therefore, more accurate more specific diagnostic techniques are required to differentiate Parkinson’s disease from other neurological conditions.