Exploration of Differences in Metabolite Concentrations by 7Teslas NMR Spectroscopy in Striatum and Subthalamic Nuclei in de Novo Parkinsonian Patients and Control Subjects

"The MRI protocol will be performed at 7T on a Siemens NMR imaging system (Magnetom Terra, Siemens Healthcare, Erlangen, Germany), the radio frequency emission and signal reception will be done through a head quadrature resonator (64-channel phase-array coil). To avoid motion-related artifacts, the patient will be seated in a supine position, with the arms along the body and the head immobilized using a suitable head restraint. The MR protocol will take place in two phases:~* Acquisition of 3D multi-slice T1 and T2-weighted morphological images to identify areas of interest;~* Acquisition of 1D RMN spectra in the right and left putamen and STN. Spectra will be acquired in volumes of interest of 15mmx15mmx15mm using a localized spectroscopy sequence with and without suppression of the water signal. Main parameters are: TR (repetition time)=3000ms; TE (echo time)=20 ms; number of repetitions=128; scan time 6min)."