Post-mortem in situ MRI has been used as an intermediate between brain histo(patho)logy and in vivo imaging. However, it is not known how comparable post-mortem in situ is to ante-mortem imaging. We report the unique situation of a patient with familial early-onset Alzheimer's disease due to a PSEN1 mutation, who underwent ante-mortem brain MRI and post-mortem in situ imaging only 4 days apart. T1-weighted and diffusion MRI was performed at 3-Tesla at both time points. Visual atrophy rating scales, brain volume, cortical thickness and diffusion measures were derived from both scans and compared. Post-mortem visual atrophy scores decreased 0.5-1 point compared with ante-mortem, indicating an increase in brain volume. This was confirmed by quantitative analysis; showing a 27% decrease of ventricular and 7% increase of whole-brain volume. This increase was more pronounced in the cerebellum and supratentorial white matter than in grey matter. Furthermore, axial and radial diffusivity decreased up to 60% post-mortem whereas average fractional anisotropy of white matter increased approximately 10%. This unique case study shows that the process of dying affects several imaging markers. These changes need to be taken into account when interpreting post-mortem MRI to make inferences on the in vivo situation.
Can post-mortem MRI be used as a proxy for in vivo? A case study / Boon, Baayla D C; Pouwels, Petra J W; Jonkman, Laura E; Keijzer, Matthijs J; Preziosa, Paolo; van de Berg, Wilma D J; Geurts, Jeroen J G; Scheltens, Philip; Barkhof, Frederik; Rozemuller, Annemieke J M; Bouwman, Femke H; Steenwijk, Martijn D. - In: BRAIN COMMUNICATIONS. - ISSN 2632-1297. - 1:1(2019), pp. 1-10. [10.1093/braincomms/fcz030]