J Clin Neurol.  2014 Jul;10(3):197-202. 10.3988/jcn.2014.10.3.197.

T2 Relaxometry Using 3.0-Tesla Magnetic Resonance Imaging of the Brain in Early- and Late-Onset Restless Legs Syndrome

• Moon HJ
• Chang Y
• Lee YS
• Song HJ
• Chang HW
• Ku J
• Cho YW

• KMID: 2179445
• DOI: http://doi.org/10.3988/jcn.2014.10.3.197

Abstract

BACKGROUND AND PURPOSE
Previous T2 relaxometry studies have provided evidence for regional brain iron deficiency in patients with restless legs syndrome (RLS). Measurement of the iron content in several brain regions, and in particular the substantia nigra (SN), in early- and late-onset RLS patients using T2 relaxometry have yielded inconsistent results. In this study the regional iron content was assessed in patients with early- and late-onset RLS using magnetic resonance imaging (MRI), and compared the results with those in controls.
METHODS
Thirty-seven patients with idiopathic RLS (20 with early onset and 17 with late onset) and 40 control subjects were studied using a 3.0-tesla MRI with a gradient-echo sampling of free induction decay and echo pulse sequence. The regions of interest in the brain were measured independently by two trained analysts using software known as medical image processing, analysis, and visualization. The results were compared and a correlation analysis was conducted to investigate which brain areas were related to RLS clinical variables.
RESULTS
The iron index in the SN was significantly lower in patients with late-onset RLS than in controls (p=0.034), while in patients with early-onset RLS there was no significant difference. There was no significant correlation between the SN iron index of the late-onset RLS group and clinical variables such as disease severity.
CONCLUSIONS
Late-onset RLS is associated with decreased iron content in the SN. This finding supports the hypothesis that regional brain iron deficiency plays a role in the pathophysiology of late-onset RLS.

Keyword

restless legs syndrome; T2 relaxometry; red nucleus; substantia nigra; iron

MeSH Terms

Brain*
Humans
Iron
Magnetic Resonance Imaging*
Red Nucleus
Restless Legs Syndrome*
Substantia Nigra
Iron

Figure

• 

  Fig. 1 Range of areas for the semiautomated ROI method in R2 relaxometry matrices. ROI: region of interest.

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