A synthetic normative template for Parkinson’s disease studies using structural and neuromelanin-sensitive magnetic resonance imaging

Parkinson's disease is a prevalent neurodegenerative disorder affecting millions of people worldwide. It is caused by degeneration of dopaminergic neurons of the substantia nigra. This has given rise to imaging-based biomarker discovery studies using neuromelanin-sensitive MRI. In this paper, we propose a normative template constructed using a combination of structural and neuromelanin-sensitive MRI that can be used in biomarker studies of Parkinson's disease. In contrast to previous template construction approaches, the proposed combination of images allows to impose further constraints on the registrations used to create the template. Our experiments demonstrate that the proposed template construction pipeline yields a consistent localisation of the substantia nigra and other brainstem structures and that the registrations used for this purpose yield smooth and invertible transformations.