The Parkinson's disease (PD) is the second most common neurodegenerative disease. It is characterized by the progressive loss of dopamine neurons in the substantia nigral which helps in managing all the body movements. There are four important symptoms of PD includes slow movement (bradykinesia), muscle stiffness (rigidity), postural instability and shaking (tremor) [1]. An increases amount of research is being done to detect the Parkinson disease at the early stages for early diagnoses and for proper treatment plan. There are many medical imaging modalities used to diagnosis PD like magnetic resonance imaging (MRI), functional imaging – which includes positron emission tomography (PET), single photon emission computed tomography (SPECT), and transcranial sonography. Each of these modalities provide a specific and unique aspect in detecting or identifying the disease. This review paper mainly focuses on the Brain functional imaging in the evaluation of Disease, current development of medical imaging modalities and its application in the diagnosis of PD.

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Parkinson Disease (pd) Magnetic Resonance Imaging (mri) Positron Emission Tomography (pet) Single Photon Emission Computed Tomography (spect) And Transcranial Sonography