@misc{Jakuszyk_Paweł_Differentiating_2025,
 author={Jakuszyk, Paweł},
 editor={Juryńczyk, Maciej : Supervisor},
 editor={Kossowski, Bartosz : Auxiliary Supervisor},
 copyright={Rights Reserved - Free Access},
 address={Warsaw},
 howpublished={online},
 school={Nencki Institute of Experimental Biology PAS},
 school={degree obtained: 2025},
 year={2025},
 publisher={Nencki Institute of Experimental Biology PAS},
 language={eng},
 abstract={Multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) are distinct autoimmune inflammatory diseases of the central nervous system (CNS), with largely distinct treatment strategies. Both conditions cause recurrent inflammation primarily affecting the optic nerve, spinal cord, and brain. NMOSD is typically associated with aquaporin-4 antibodies (AQP4-IgG) and targets astrocytes, whereas MS is driven by cell-mediated autoreactivity against myelin, leading to demyelination. Diagnosing MS and NMOSD relies heavily on conventional MRI, but overlapping imaging features often complicate differentiation. Although AQP4-IgG detection is the diagnostic gold standard for NMOSD, its availability is limited, and assay sensitivity varies, leading to potential false-negative results. Misdiagnosis remains a challenge, highlighting the need for new, accessible, non-invasive diagnostic tools. Advanced, non-conventional MRI techniques, such as diffusion-weighted imaging, T1 relaxation rates, quantitative susceptibility mapping, and volumetry, offer deeper insights into CNS pathology by assessing both macro- and microstructural pathological processes, even in regions that appear normal on conventional imaging. This thesis investigates whether such techniques can distinguish relapsing-remitting MS from AQP4-IgG-positive NMOSD (AQP4- NMOSD) by assessing damage in the brain and cervical spinal cord compared to healthy controls. In the brain, neurite density index (NDI) in white matter tracts was examined, differentiating between lesion-traversing and lesion-free fibres. The cerebral cortex was evaluated based on T1 relaxation rates, identification of cortical lesions, and volumetric analysis. Volumetric analyses were also performed for white matter and deep grey matter. Additionally, in MS, the study explored the relationship between lesion-free white matter fibres and both cortical lesions and paramagnetic rim lesions. In MS, NDI reductions were widespread across both lesion-traversing and lesion-free white matter fibres, along with white matter volume loss. In contrast, AQP4-NMOSD showed NDI reduction only in lesion- traversing fibers and no white matter atrophy. Lower T1 relaxation rates were observed in most cortical regions in MS, but only in a few regions in AQP4-NMOSD. Neither disease showed cortical atrophy, though deep grey matter volume was reduced in MS. Notably, MS exhibited a negative correlation between cortical lesion burden and NDI in lesion-free white matter fibres, whereas no association was observed with paramagnetic rim lesions.},
 title={Differentiating multiple sclerosis and aquaporin-4 antibody-positive neuromyelitis optica spectrum disorders : newinsights from non-conventional magnetic resonance imaging : PhD thesis},
 type={Text},
 URL={http://rcin.org.pl/ibd/Content/246790/WA488_283593_20843_Jakuszyk-Pawel-2025.pdf},
 keywords={Magnetic resonance imaging, Multiple sclerosis, Neuromyelitis optica spectrum disorders, Non-coventional imaging, White matter damage},
}