Computer-based magnetic resonance imaging as a tool in clinical diagnosis in neurodegenerative diseases

ABSTRACT

Magnetic resonance imaging (MRI) is one of the core elements within the differential diagnostic work-up of patients with neurodegenerative diseases such as dementia syndromes, Parkinsonian syndromes, and motor neuron diseases. Currently, computerized MRI analyses are not routinely used for individual diagnosis; however, they have improved the anatomical understanding of pathomorphological alterations in various neurodegenerative diseases by quantitative comparisons between patients and controls at the group level. For multiparametric MRI protocols, including T1-weighted MRI, diffusion-weighted imaging, and intrinsic functional connectivity MRI, the potential as a surrogate marker is a subject of investigation. The additional value of MRI with respect to diagnosis at the individual level and for future disease-modifying multicentre trials remains to be defined. Here, we give an overview of recent applications of multiparametric MRI to patients with various neurodegenerative diseases. Starting from applications at the group level, continuous progress of a transfer to individual diagnostic classification is ongoing.

KEYWORDS:

• Neuroimaging
• neurodegenerative diseases
• diffusion tensor imaging
• intrinsic functional connectivity
• neurodegeneration
• clinical diagnosis

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Key issues

• Advances in neuroimaging research in Alzheimer’s disease have enabled mapping of diverse molecular, functional, and structural aspects of Alzheimer’s disease pathology in increasing temporal and regional detail.

• Neuroimaging in Parkinson’s disease addresses the disease’s complexity by demonstration of the affectation of many brain regions, structural and functional connections (neurotransmitter systems), and neurocognitive systems.

• In motor neuron diseases, neuroimaging studies have shown that anatomical and functional lesions are widespread beyond precentral cortices and corticospinal tracts.

• MRI-based neuroimaging is increasingly used in the ongoing search for sensitive and reliable biomarkers of progressive neurodegeneration that could be used to assess the effect of therapeutic intervention on brain structure and function in future clinical trials.

• Computerized MRI analyses in neurodegenerative diseases are increasingly developed for the use in individual diagnosis, since they have improved the anatomical understanding of pathomorphological alterations in gray and white matter in various neurodegenerative diseases.

• Neuroimaging has brought unparalleled in vivo pathological insights into neurodegenerative diseases, now also starting to include the presymptomatic landscape; core mechanisms may be revealed that have implications for future therapeutics in neurodegenerative diseases and neuroimaging has shown its great potential for generating biomarkers.

• Beyond the key role of cross-sectional studies to identify regional affectation patterns of neurodegenerative diseases, it is a future task to expand the cross-sectional findings to group-based longitudinal markers.

• Currently, the concept of disease propagation in specific neurodegenerative diseases cannot be appropriately monitored by MRI-based neuroimaging tools, but promising approaches exist, that way increasing the potential of multiparametric neuroimaging as a ‘dry’ surrogate marker applicable at the individual level.