Measurement of brain volumes
We obtained three-dimensional T1-weighted structural MRI scans of the head and transferred these data, blinded to trial-group status, to an independent image-analysis provider that performed quality control, processing and volumetric analyses according to established methods. Whole-brain and regional volume changes were calculated using a validated pipeline implemented in VivoQuantTM, composed of a preprocessing module and a multi-atlas segmentation module, followed by visual inspection and manual editing if needed