Quantitative Susceptibility Mapping and Iron Deposition in Autopsy-Confirmed Progressive Supranuclear Palsy

Quantitative susceptibility mapping (QSM) is a promising neuroimaging biomarker for detecting abnormal iron deposition in progressive supranuclear palsy (PSP); however, the QSM profile and its accuracy in autopsy-confirmed PSP remain unexplored.

The aim of the study was to elucidate and validate the QSM profiles in autopsy-confirmed PSP.

Eight patients with a clinically diagnosed PSP syndrome (PSPS) underwent antemortem 3 T magnetic resonance imaging (MRI) scanning and subsequent pathological diagnosis, confirming 6 PSP pathology and 2 multiple system atrophy (MSA) pathology cases. QSM analysis and Prussian blue staining were performed across subcortical regions.

PSP cases showed higher susceptibility than age-matched controls in the pallidum, subthalamic nucleus, substantia nigra, and cerebellar dentate (false discovery rate [FDR]-corrected P < 0.05). PSP had higher susceptibility in the subthalamic nucleus and lower susceptibility in the putamen than the clinically atypical MSA (P = 0.08). Subcortical susceptibilities correlated with Prussian blue-stained areas (r = 0.63, P < 0.001).

QSM could be a reliable measure to evaluate abnormal iron accumulation patterns in PSP.