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Imaging Brain Functional and Metabolic Changes in Restless Legs Syndrome

  • Neuroimaging (DJ Brooks)
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Abstract

Even though the pathophysiology of restless legs syndrome is not completely understood, several imaging studies have contributed to our understanding of the disease. Functional and metabolic impairment seems to be the pathophysiological core, tied to a single brain network or multiple connected brain networks, via neurotransmitter modifications. Positron emission tomography and single photon emission computed tomography studies support a dysfunction of dopaminergic pathways, involving not only the nigrostriatal pathway but also the mesolimbic pathway. Furthermore, a possible role of serotonergic neurotransmission has been suggested. Functional magnetic resonance imaging studies have demonstrated in restless legs syndrome patients a pathologic activation of cerebral areas belonging to both the sensorimotor and the limbic networks. Proton magnetic resonance spectroscopy has confirmed abnormality of the limbic system and suggested the presence of a glutamatergic disorder. Finally magnetic resonance studies using iron-sensitive sequences have demonstrated reduced iron content in several regions of the brain of restless legs syndrome patients. In this review we attempt to integrate all current imaging study results into a convergent pathophysiological interpretation.

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Conflict of Interest

Giovanni Rizzo has received grant support from Neureca Onlus.

Caterina Tonon, David Manners, Claudia Testa, and Raffaele Lodi declare that they have no conflict of interest.

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This article does not contain any studies with human or animal subjects performed by any of the authors.

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Authors and Affiliations

  1. Functional MR Unit, Department of Biomedical and NeuroMotor Sciences (DiBiNeM), University of Bologna, Via Massarenti 9, 40138, Bologna, Italy

    Giovanni Rizzo, Caterina Tonon, David Manners, Claudia Testa & Raffaele Lodi

  2. IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy

    Giovanni Rizzo

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  1. Giovanni Rizzo
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  2. Caterina Tonon
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  3. David Manners
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Correspondence to Raffaele Lodi.

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This article is part of the Topical Collection on Neuroimaging

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Rizzo, G., Tonon, C., Manners, D. et al. Imaging Brain Functional and Metabolic Changes in Restless Legs Syndrome. Curr Neurol Neurosci Rep 13, 372 (2013). https://doi.org/10.1007/s11910-013-0372-1

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