Preparation of fixed mouse brains for MRI

► A high prevalence of fixation artifacts are observed in fixed mouse brain MR images. ► Two artifacts from perfusion fixation are described and their causes identified. ► Hyperintense rim around brain occurs when using powder perfusates and high flow rate. ► Inverse contrast and cerebellar deformation occurs upon inadequate fixation. ► These artifacts are unacceptable for quantitative data analysis and must be avoided.