A 3D nigrosome atlas based on multi-modal histology and multi-parametric quantitative MRI

MRI holds great promise to unravel the selective vulnerability and functional differentiation of the nigrosomes in the human substantia nigra pars compacta. Based on block-face imaging and calbindin-D28K immunohistochemistry, we constructed a 3D nigrosome atlas. Using this atlas, we demonstrate several nigrosomes to show increased R2* values in post mortem tissue. Our results further challenge the common identification of the nigrosomes with hyperintense structures in in vivo MRI, particularly nigrosome 1 and the swallow tail sign.