0000000000954502
AUTHOR
Adriane Gröger
Power estimation for non-standardized multisite studies
A concern for researchers planning multisite studies is that scanner and T1-weighted sequence-related biases on regional volumes could overshadow true effects, especially for studies with a heterogeneous set of scanners and sequences. Current approaches attempt to harmonize data by standardizing hardware, pulse sequences, and protocols, or by calibrating across sites using phantom-based corrections to ensure the same raw image intensities. We propose to avoid harmonization and phantom-based correction entirely. We hypothesized that the bias of estimated regional volumes is scaled between sites due to the contrast and gradient distortion differences between scanners and sequences. Given this…
Increased structural white and grey matter network connectivity compensates for functional decline in early multiple sclerosis
Background: The pathology of multiple sclerosis (MS) consists of demyelination and neuronal injury, which occur early in the disease; yet, remission phases indicate repair. Whether and how the central nervous system (CNS) maintains homeostasis to counteract clinical impairment is not known. Objective: We analyse the structural connectivity of white matter (WM) and grey matter (GM) networks to understand the absence of clinical decline as the disease progresses. Methods: A total of 138 relapsing–remitting MS patients (classified into six groups by disease duration) and 32 healthy controls were investigated using 3-Tesla magnetic resonance imaging (MRI). Networks were analysed using graph the…
Association of smoking but not HLA-DRB1*15:01, APOE or body mass index with brain atrophy in early multiple sclerosis
Background: The course of multiple sclerosis (MS) shows substantial inter-individual variability. The underlying determinants of disease severity likely involve genetic and environmental factors. Objective: The aim of this study was to assess the impact of APOE and HLA polymorphisms as well as smoking and body mass index (BMI) in the very early MS course. Methods: Untreated patients ( n = 263) with a recent diagnosis of relapsing-remitting (RR) MS or clinically isolated syndrome underwent standardized magnetic resonance imaging (MRI). Genotyping was performed for single-nucleotide polymorphisms (SNPs) rs3135388 tagging the HLA-DRB1*15:01 haplotype and rs7412 (Ɛ2) and rs429358 (Ɛ4) in APOE. …
MSJ763541_supplementary_material – Supplemental material for Association of smoking but not HLA-DRB1*15:01, APOE or body mass index with brain atrophy in early multiple sclerosis
Supplemental material, MSJ763541_supplementary_material for Association of smoking but not HLA-DRB1*15:01, APOE or body mass index with brain atrophy in early multiple sclerosis by Christiane Graetz, Adriane Gröge, Felix Luessi, Anke Salmen, Daniela Zöller, Janine Schultz, Nelly Siller, Vinzenz Fleischer, Barbara Bellenberg, Achim Berthele, Viola Biberacher, Joachim Havla, Michael Hecker, Reinhard Hohlfeld, Carmen Infante-Duarte, Jan S Kirschke, Tania Kümpfel, Ralf Linker, Friedemann Paul, Steffen Pfeuffer, Philipp Sämann, Gerrit Toenges, Frank Weber, Uwe K Zettl, Antje Jahn-Eimermacher, Gisela Antony, Sergiu Groppa, Heinz Wiendl, Bernhard Hemmer, Mark Mühlau, Carsten Lukas, Ralf Gold, Chri…