The CATI (Centre pour l’Acquisition et le Traitement automatisé des images) is a French national platform that supports large multicenter neuroimaging studies. In this specific context, the CATI is developing a quantitative MRI solution, more suitable for lesion characterisation or follow up studies than conventional T1-, T2- or T2*-weighted MR images. The purpose of this work was to define an acquisition protocol dedicated to T2* which is the first step towards standardization. T2* is an endogenous biomarker of paramagnetic materials like iron or melanin, of particular interest to investigate Parkinson’s Disease (PD) [1]. The dedicated MRI protocol will have to meet several specific requirements: 1. being compatible with product sequences provided by the three main manufacturers of 3T MRI scanners without any optional license ; 2. providing whole brain coverage at a standard millimeter isotropic resolution with identical sequence parameters; 3. ensuring a good measurement accuracy and reproducibility (error rate lower than 5% in the range of 35 to 50ms [1]) using a 32 channel receive array coil; 4. lasting less than ten minutes to be suitable for clinical routine.Acquisitions have been done on 3T MRI systems from the three major manufacturers (Siemens Healthcare, Erlangen; GE Healthcare, Milwaukee, WI, USA; Philips Healthcare, Best, Netherlands). The parameters of a 3D multi Gradient Echo Recalled (mGRE) sequence were iteratively optimized until a set fulfilling the requirements listed above was found. T2* maps were then estimated by a complex reconstruction in order to take into account fat signal and macroscopic ΔB₀ contribution [2]. A unique Python code was used, independent of manufacturers, to ensure that no difference was introduiced by image post-processing. Finally, in order to evaluate the sequence sensitivity, a Monte Carlo simulation study was performed. Calculations were based on the use of 32 channel head coils and considering experimental Signal to Noise Ratio (SNR) retrieved from in vivo acquisitions and realistic T2* values, thus providing the expected performance of the optimized parameter set.Figure 1 summarizes the 3D mGRE sequence parameters compatible with MRI scanners of the three main manufacturers. The major limitations were related to the number of echoes that could be tuned and to the available data storage space. Monte Carlo simulations performed to evaluate the T2* sensitivity, robustness and reproducibility are displayed in figure 2. The results indicate a high accuracy level for T2* values in the range 35-50 ms, keeping the error rate below 5% for this range. R2* (1/T2*) maps obtained for the three manufacturers are displayed in figure 3.We successfully managed to implement a sequence that meets with our specific requirements. This “universal” sequence, tuned for 32 channel head coils, can be acquired with all 3T MRI systems from the three main manufacturers and allows to build T2* maps that are reliable and repeatable for a large range of values, particularly for the values (35-50ms) expected for PD in deep brain regions [1]. This standardized protocol will soon be installed on the MRI systems of French and European partners belonging to the CATI network and investigating PD.