Iron quantification in basal ganglia using quantitative susceptibility mapping in a patient with ALS: a case report and literature review

Abstract

BackgroundQuantitative susceptibility mapping (QSM) is a magnetic resonance imaging (MRI) technique that can measure the magnetic susceptibility of tissues, which can reflect their iron content. QSM has been used to detect iron accumulation in cortical and subcortical brain regions. However, its application in subcortical regions such as the basal ganglia, particularly the putamen, is rare in patients with amyotrophic lateral sclerosis (ALS).Case presentation and literature reviewWe present the case of a 40-year-old male patient with ALS who underwent an MRI for QSM. We compared his QSM images with those of a control subject and performed a quantitative analysis of the magnetic susceptibility values in the putamen regions. We also reviewed the literature on previous QSM studies in ALS and summarized their methods and findings. Our QSM analysis revealed increased magnetic susceptibility values in the bilateral putamen of the ALS patient compared to controls, indicating iron overload. This finding is consistent with previous studies reporting iron dysregulation in subcortical nuclei in ALS. We also discussed the QSM processing techniques used in our study and in the literature, highlighting their advantages and limitations.ConclusionThis case report demonstrates the potential of QSM as a sensitive MRI biomarker for evaluating iron levels in subcortical regions of ALS patients. QSM can provide quantitative information on iron deposition patterns in both motor and extra-motor areas of ALS patients, which may help understand the pathophysiology of ALS and monitor disease progression. Further studies with larger samples are needed to validate these results and explore the clinical implications of QSM in ALS.

Quantitative susceptibility mapping for iron monitoring of multiple subcortical nuclei in type 2 diabetes mellitus: a systematic review and meta-analysis

“…To sum up, this meta-analysis helps confirm QSM as a promising biomarker for detecting subcortical iron abnormalities in T2DM ( 8 , 17 , 28 , 31 , 40 , 41 ). QSM offers several advantages over other MRI techniques, such as susceptibility weighted imaging (SWI), for quantifying iron because of its specificity for iron and insensitivity to confounding factors ( 17 , 61 ). The consistency of QSM findings across studies supports its utility in multi-center studies ( 80 ).…”

MRI biomarkers and neuropsychological assessments of hippocampal and parahippocampal regions affected by ALS: A systematic review

“…Magnetic resonance imaging (MRI) biomarker alterations provide a helpful window into understanding the progression of ALS 25,26 . MRI is a non‐invasive and multiparametric device that can measure structural and functional changes in the hippocampus and adjacent regions in ALS 27,28 .…”

Iron quantification in basal ganglia: quantitative susceptibility mapping as a potential biomarker for Alzheimer’s disease – a systematic review and meta-analysis

“…Another critical but less highlighted aspect of AD pathology is deregulation of iron homeostasis. Iron, an essential element for brain function ( Ravanfar et al, 2021 ; Ghaderi et al, 2023 ), can be neurotoxic in excess ( Salvador et al, 2010 ). Notably, patients with AD exhibit pronounced iron accumulation in brain regions, such as the cortex and basal ganglia ( Ward et al, 2014 ; Liu et al, 2018 ), which is thought to exacerbate neurodegeneration ( Ndayisaba et al, 2019 ; Wang et al, 2020 ).…”

“…Recent advances in post-processing neuroimaging methods have provided a novel tool for assessing brain iron concentration ( Ghaderi et al, 2023 ). The relevance of iron accumulation in AD pathology warrants a sophisticated approach to its quantification, which is now feasible with advancements in magnetic resonance imaging (MRI) technologies ( Ghaderi and Mohammadi, 2023 ; Mohammadi and Ghaderi, 2023 ), particularly quantitative susceptibility mapping (QSM) ( Ghaderi et al, 2023 ). QSM provides quantitative measurements of tissue iron content, overcoming limitations of other MRI techniques such as R2* and phase imaging for quantifying iron ( Liu et al, 2015 ; Ravanfar et al, 2021 ; Ghaderi et al, 2023 ).…”

“…The relevance of iron accumulation in AD pathology warrants a sophisticated approach to its quantification, which is now feasible with advancements in magnetic resonance imaging (MRI) technologies ( Ghaderi and Mohammadi, 2023 ; Mohammadi and Ghaderi, 2023 ), particularly quantitative susceptibility mapping (QSM) ( Ghaderi et al, 2023 ). QSM provides quantitative measurements of tissue iron content, overcoming limitations of other MRI techniques such as R2* and phase imaging for quantifying iron ( Liu et al, 2015 ; Ravanfar et al, 2021 ; Ghaderi et al, 2023 ). QSM allows for the precise measurement of magnetic susceptibility (χ), a property that reflects the relative ability of a tissue to alter its magnetic field ( Wang et al, 2017 ).…”