Some reports have described early features of PD such as (SPECT) imaging of the dopamine transporter that demonstrated the reduction of dopamine transporter in the striatum body at the early stage of PD and degeneration of the cardiac sympathetic nerve at the beginning of the disease process of PD; this occurs before neuronal cell loss is present in the dorsal vagal nucleus; This fact accounts for reduced cardiac uptake of meta-iodobenzylguanidine (MIBG), a physiological analog of norepinephrine. However, these diagnostic methods are not often performed. Therefore, more sensitive methods are needed to help improve the accuracy of diagnosis of PD.