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Szentkirályi A, Hermesdorf M, Sundermann B, Czira M, Teismann H, Wulms N, Minnerup H, Young P, Berger K. Periodic limb movements in sleep are linked to decreased hippocampus and amygdala volumes in the population-based BiDirect Study. Sleep 2023; 46:6795532. [PMID: 36330698 DOI: 10.1093/sleep/zsac263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/30/2022] [Indexed: 11/06/2022] Open
Abstract
STUDY OBJECTIVES Even though numerous studies indicate that sleep disorders are associated with altered brain morphology, MRI studies focusing on periodic limb movements in sleep (PLMS) are scarce. Our aim was to investigate the association of PLMS with global and regional gray matter volumes as well as white matter hyperintensity (WMH) volume. METHODS One hundred and eighty-nine subjects (57.0 ± 7.8 years, women: 50.5%) of the population-based BiDirect Study underwent a single-night polysomnography (PSG). Standard criteria of the American Academy of Sleep Medicine were applied to evaluate sleep characteristics and calculate the PLMS index (PLMSI). T1w and FLAIR images were acquired with cerebral MRI at 3 Tesla. Voxel-based morphometry was performed to determine the total gray matter volume as well as the volume of cortical segments and subcortical gray matter areas using SPM12 and CAT12. The WMH volume was quantified with the Brain Intensity AbNormality Classification Algorithm. The independent relationship between MRI markers and PLMSI was analyzed using multivariable linear regression with adjustment for age, sex, body mass index, intracranial volume, PSG scorer, PSG device, sleep apnea, and the use of antidepressants. RESULTS PLMSI was not significantly related to global gray matter volume and WMH volume. However, significant inverse associations of the PLMSI with the volume of the hippocampus (left and right hemisphere) and left amygdala were observed. CONCLUSIONS A significant relationship between a higher PLMSI and lower volumes of the hippocampus and amygdala was found among the participants of the BiDirect Study. Since these associations are based on exploratory analyses, further replications are required before drawing firm conclusions.
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Affiliation(s)
- András Szentkirályi
- Institute of Epidemiology and Social Medicine, University of Münster, Münster, Germany
| | - Marco Hermesdorf
- Institute of Epidemiology and Social Medicine, University of Münster, Münster, Germany
| | - Benedikt Sundermann
- Clinic of Radiology, University Hospital Münster, Münster, Germany.,Institute of Radiology and Neuroradiology, Evangelisches Krankenhaus, Medical Campus University of Oldenburg, Oldenburg, Germany.,Research Center Neurosensory Science, University of Oldenburg, Oldenburg, Germany
| | - Maria Czira
- Johannes Keller General Practice, Greven, Germany
| | - Henning Teismann
- Institute of Epidemiology and Social Medicine, University of Münster, Münster, Germany
| | - Niklas Wulms
- Institute of Epidemiology and Social Medicine, University of Münster, Münster, Germany
| | - Heike Minnerup
- Institute of Epidemiology and Social Medicine, University of Münster, Münster, Germany
| | - Peter Young
- Medical Park/Neurological Clinic Reithofpark, Bad Feilnbach, Germany
| | - Klaus Berger
- Institute of Epidemiology and Social Medicine, University of Münster, Münster, Germany
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Zang QL, Zheng JH, Ma JJ, Zhang Q, Huang PP, Shen NN, Miao W. Neuroanatomy and Functional Connectivity in Patients with Parkinson's Disease with or without Restless Legs Syndrome. Neurol Ther 2022; 11:1625-1636. [PMID: 35999489 DOI: 10.1007/s40120-022-00397-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 08/08/2022] [Indexed: 11/30/2022] Open
Abstract
INTRODUCTION Restless legs syndrome (RLS) is a common non-motor symptom in Parkinson's disease (PD), but its pathogenesis remains unclear. This study aimed to explore the potential neural substrates of RLS in a large sample of patients with PD. METHODS A total of 42 patients with PD with RLS and 124 patients with PD without RLS were prospectively recruited at our hospital between February 2019 and October 2020 and underwent structural and resting-state functional magnetic resonance imaging. Differences between the two patient groups were assessed using voxel-based morphometry and functional connectivity analysis. PD duration, Part III of the Movement Disorder Society's Unified Parkinson's Disease Rating Scale (MDS-UPDRS-III) score, and levodopa equivalent daily dose were treated as covariates. RESULTS Patients with PD with RLS had significantly larger gray matter volume in the bilateral posterior cingulate cortex than patients with PD without RLS (FDR-adjusted P < 0.05). Compared to patients without RLS, those with RLS had significantly lower functional connectivity between the left central opercular cortex and the bilateral precentral gyri and postcentral gyri (FDR-adjusted P < 0.001). CONCLUSION Our study provides the first evidence that in patients with PD, RLS is associated with significantly larger gray matter volume in the posterior cingulate cortex and lower resting-state functional connectivity within the sensorimotor network. Our results may help clarify the pathophysiology of RLS in PD and identify possible therapeutic targets.
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Affiliation(s)
- Qiu Ling Zang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, 1 Jian She East Road, Zhengzhou, 450007, Henan Province, People's Republic of China
| | - Jin Hua Zheng
- Department of Neurology, Henan Provincial People's Hospital, No. 7, Weiwu Road, Zhengzhou, 450003, Henan Province, People's Republic of China
| | - Jian Jun Ma
- Department of Neurology, Henan Provincial People's Hospital, No. 7, Weiwu Road, Zhengzhou, 450003, Henan Province, People's Republic of China.
| | - Qi Zhang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, 1 Jian She East Road, Zhengzhou, 450007, Henan Province, People's Republic of China
| | - Pei Pei Huang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, 1 Jian She East Road, Zhengzhou, 450007, Henan Province, People's Republic of China
| | - Nan Nan Shen
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, 1 Jian She East Road, Zhengzhou, 450007, Henan Province, People's Republic of China
| | - Wang Miao
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, 1 Jian She East Road, Zhengzhou, 450007, Henan Province, People's Republic of China.
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3
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Liu K, Su H, Song J, Cui S, Huang X, Zhou Y, Liu X, Shan X, Yan Z, Ye X. Altered gray matter volume in children with newly diagnosed type 1 diabetes mellitus. Pediatr Res 2022. [PMID: 35918400 DOI: 10.1038/s41390-022-02227-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 06/29/2022] [Accepted: 07/08/2022] [Indexed: 11/08/2022]
Abstract
BACKGROUND Type 1 diabetes mellitus (T1DM) affects the development of cognitive function in children, which may be due to deficits in brain structures or functions. It is unclear whether children with T1DM experience alterations in the gray matter (GM) structure at the initial stages of the disease. This study investigated GM structure alterations in children with newly diagnosed T1DM. METHODS Based on 3D T1-weighted MR images, we investigated the gray matter volume (GMV) of 35 newly diagnosed T1DM children and 35 age- and sex-matched healthy controls using voxel-based morphometry. The brain regions with significant differences in GMV between the newly diagnosed T1DM children and the controls were extracted and the correlation with clinical data was assessed. RESULTS Compared with the control group, children with newly diagnosed T1DM had a lower GMV in the right inferior and middle temporal gyri, right lingual gyrus, and left superior frontal gyrus. In T1DM subjects, the GMV of the right middle temporal gyrus was positively correlated with IQ but was negatively correlated with HbA1c. CONCLUSIONS Our findings provide compelling evidence that GM abnormalities occur during early disease stages in T1DM children, which may be a potential neurobiological mechanism underlying cognitive deficits. IMPACT Using an efficient method to analyze gray matter changes in T1DM is very important. The anterior, posterior, and temporal brain regions are susceptible to T1DM in children. Recent glucose variability may affect regional gray matter volume in children with newly diagnosed T1DM. Structural changes were documented in the gray matter of the brain even at the early stages of the disease in children with T1DM.
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Mail Gurkan Z, Tantik Pak A, Nacar Dogan S, Sengul Y. Microstructural changes of basal ganglia in migraine with restless legs syndrome: findings from a neuroimaging study. Sleep Biol Rhythms 2022; 20:361-369. [PMID: 38469422 PMCID: PMC10899932 DOI: 10.1007/s41105-022-00376-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Accepted: 02/01/2022] [Indexed: 01/18/2023]
Abstract
In this study, it is planned to investigate the integrity of the basal ganglia structures in migraineurs with restless legs syndrome (RLS) to explore this relationship. In this study, 58 patients who were diagnosed migraine and 51 healthy controls (HCs) were included. Patients diagnosed with migraine were divided into two groups: Group I (migraine without RLS) and Group II (migraine with RLS). The integrity of basal ganglia was evaluated with region of interest diffusion tensor imaging method which allows us to assess microstructural changes of the tissue. The mean age of the patients was 35.98 ± 7.92 years, and the mean age of the HCs was 33.84 ± 11.06. 84.5% (n = 49) of the patients were female and 15.5% (n = 9) were male. 82.4% (n = 42) of the HCs were female, 17.6% (n = 9) were male. The number of the patients without RLS was 41 (Group I), and the number of the patients with RLS was 17 (Group II). When basal ganglia structures were compared between groups of the patients with and without RLS, the fractional anisotropy (FA) value of the left putamen differed (Group I: 0.30 ± 0.06 vs. Group II: 0.25 ± 0.7, p = 0.01). The significant relationship was found attack frequency and presence of RLS with left putamen FA values according to multiple regression analysis. It was determined in this study that the changes in the microstructure of putamen, one of the basal ganglia structures, may be associated with the presence of RLS in migraineurs.
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Affiliation(s)
- Zahide Mail Gurkan
- Neurology Department of Gaziosmanpasa Training and Research Hospital, Gaziosmanpasa, Istanbul, Turkey
| | - Aygul Tantik Pak
- Neurology Department of Gaziosmanpasa Training and Research Hospital, Gaziosmanpasa, Istanbul, Turkey
| | - Sebahat Nacar Dogan
- Radiology Department of Gaziosmanpasa Training and Research Hospital, Gaziosmanpasa, Istanbul, Turkey
| | - Yıldızhan Sengul
- Neurology Department of Gaziosmanpasa Training and Research Hospital, Gaziosmanpasa, Istanbul, Turkey
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Sheng L, Zhao P, Ma H, Qi L, Yi Z, Shi Y, Zhong J, Shi H, Dai Z, Pan P. Grey matter alterations in restless legs syndrome: A coordinate-based meta-analysis. J Sleep Res 2021; 30:e13298. [PMID: 33554365 DOI: 10.1111/jsr.13298] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 01/14/2021] [Accepted: 01/15/2021] [Indexed: 01/18/2023]
Abstract
Brain structural abnormalities in idiopathic restless legs syndrome have long been debated. Voxel-based morphometry is an objective structural magnetic resonance imaging technique to investigate regional grey matter volume or density differences between groups. In the last decade, voxel-based morphometry studies have exhibited inconsistent and conflicting findings regarding the presence and localization of brain grey matter alterations in restless legs syndrome. We therefore conducted a coordinate-based meta-analysis to quantitatively examine whether there were consistent grey matter findings in restless legs syndrome using the latest algorithms, seed-based d mapping with permutation of subject images. We included 12 voxel-based morphometry studies (13 datasets, 375 patients and 385 healthy controls). Our coordinate-based meta-analysis did not identify evidence of consistent grey matter alterations in restless legs syndrome. Grey matter alterations via voxel-based morphometry analysis are not therefore recommended to be used as a reliable surrogate neuroimaging marker for restless legs syndrome. This lack of consistency may be attributed to differences in sample size, genetics, gender distribution and age at onset, clinical heterogeneity (clinical course, anatomical distribution of symptoms, disease severity, disease duration, abnormal sensory profiles and comorbidity), and variations in imaging acquisition, data processing and statistical strategies. Longitudinal studies with multimodal neuroimaging techniques are needed to determine whether structural changes are dynamic and secondary to functional abnormalities.
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Affiliation(s)
- LiQin Sheng
- Department of Neurology, Kunshan Hospital of Traditional Chinese Medicine, Kunshan, China
| | - PanWen Zhao
- Department of Central Laboratory, Affiliated Yancheng Hospital, School of Medicine, Southeast University, Yancheng, China
| | - HaiRong Ma
- Department of Neurology, Kunshan Hospital of Traditional Chinese Medicine, Kunshan, China
| | - Liang Qi
- Second People's Hospital of Huai'an City, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, China
| | - ZhongQuan Yi
- Department of Central Laboratory, Affiliated Yancheng Hospital, School of Medicine, Southeast University, Yancheng, China
| | - YuanYuan Shi
- Department of Central Laboratory, Affiliated Yancheng Hospital, School of Medicine, Southeast University, Yancheng, China
| | - JianGuo Zhong
- Department of Neurology, Affiliated Yancheng Hospital, School of Medicine, Southeast University, Yancheng, China
| | - HaiCun Shi
- Department of Neurology, Affiliated Yancheng Hospital, School of Medicine, Southeast University, Yancheng, China
| | - ZhenYu Dai
- Department of Radiology, Affiliated Yancheng Hospital, School of Medicine, Southeast University, Yancheng, China
| | - PingLei Pan
- Department of Central Laboratory, Affiliated Yancheng Hospital, School of Medicine, Southeast University, Yancheng, China.,Department of Neurology, Affiliated Yancheng Hospital, School of Medicine, Southeast University, Yancheng, China
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6
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Wang L, Liu C, Hou Y, Zhan S, Zhang Z, Wang J, Wang Y. Altered cortical gray matter volume and functional connectivity after transcutaneous spinal cord direct current stimulation in idiopathic restless legs syndrome. Sleep Med 2020; 74:254-61. [DOI: 10.1016/j.sleep.2020.07.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 07/18/2020] [Accepted: 07/20/2020] [Indexed: 01/18/2023]
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Gitaí LLG, Éckeli AL, Sobreira-Neto MA, Diniz PRB, Santos AC, Júnior WM, Fernandes RMF. Which Factors in Spinocerebellar Ataxia Type 3 Patients Are Associated with Restless Legs Syndrome/Willis-Ekbom Disease? Cerebellum 2021; 20:21-30. [PMID: 32946033 DOI: 10.1007/s12311-020-01170-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
There is evidence of a higher prevalence of restless legs syndrome/Willis-Ekbom disease (RLS/WED) in individuals with spinocerebellar ataxia type 3 (SCA3), although the factors underlying this association remain unknown. The present study aimed to determine the prevalence of RLS/WED in SCA3 patients and to investigate which factors of SCA3 patients are associated with presence of RLS/WED. From February to August of 2006, we carried out clinical interviews in 40 controls and 40 SCA3 patients, diagnosed and followed up at Faculty of Medicine of Ribeirão Preto, University of São Paulo. Twenty-seven SCA3 patients were submitted to a detailed clinical protocol, electroneuromyography, blood work up, polysomnography (PSG), suggested immobilization test (SIT), and magnetic resonance image (MRI). RLS/WED was found in 27.5% of SCA3 patients and 2.5% of normal controls (p = 0.003). The factors related to RLS/WED in SCA3 patients were female gender, age at start of the symptoms of ataxia after 30 years, presence of peripheral neuropathy, and documented iron deficiency. Among SCA3 patients, those with RLS showed higher values of maximal discomfort level and discomfort level sum compared to non-RLS individuals on SIT. There is a relation between RLS/WED and SCA3, which seems to be resultant of different factors whose identification could improve the quality of assistance to those patients as well as to promote a better comprehension of the pathophysiology of both RLS/WED and SCA3.
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Wang H, Han X, Jin M, Zhang P, Wang Z, Lv H, Ding HY, Zhang ZY, Zhao PF, Li J, Yang ZH, Liu WH, Wang ZC. Patterns of Gray Matter Volume Alterations in Hemodialysis Patients With and Without Restless Legs Syndrome: Evidence From a Voxel-Based Morphometry Study. J Comput Assist Tomogr 2020; 44:533-9. [PMID: 32697523 DOI: 10.1097/RCT.0000000000001034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
PURPOSE The purpose of this study was to investigate the differences of gray matter volume (GMV) alteration patterns between hemodialysis with restless legs syndrome (HD-RLS) and hemodialysis without restless legs syndrome (HD-nRLS) patients using voxel-based morphometry. METHODS Twenty-three HD-RLS patients, 27 HD-nRLS patients, and 27 age-, sex-, and education-matched healthy controls were included in this study. One-way analysis of covariance and post hoc analyses were used to assess differences in GMV, demographics, and clinical data among the 3 groups. Pearson correlation analysis was conducted between altered GMV in the HD-RLS group and clinical data. RESULTS Compared with HD-nRLS patients, HD-RLS patients showed decreased GMV in the left primary motor cortex (false discovery rate corrected, P < 0.05). Compared with the healthy controls, both HD subgroups (ie, those with and without RLS) exhibited consistent GMV changes, including decreased GMV in the bilateral anterior cingulate and paracingulate gyrus and left middle temporal gyrus (false discovery rate corrected, P < 0.05). The GMV values in the left precentral gyrus were negatively correlated with the RLS rating scores (r = 0.2138, P = 0.0263). CONCLUSIONS This abnormal decreased GMV in the sensorimotor cortex provides evidence for a sensory processing disorder in RLS that may be involved in the pathogenesis of RLS in HD patients.
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Abstract
OBJECTIVES In this study we aimed to investigate corpus callosum shape differences between restless leg syndrome patients and healthy controls, and to determine whether disease severity and duration are indicators for corpus callosum deformation in RLS patients. METHODS This study was conducted using the magnetic resonance imaging scans of 33 restless leg syndrome patients and 33 control subjects. Landmarks were marked on the digital images and callosal landmark coordinate data were used to assess shape difference by performing Generalized Procrustes analysis. The shape deformation from controls to the patients was evaluated performing the Thin Plate Spline approach. RESULTS There was a statistically significant shape difference between the groups. Highest deformation was determined at the posterior midbody of the corpus callosum. Growth curve analyses showed that with the increase in disease duration and severity, the CC size decreased. DISCUSSION The present study demonstrated callosal shape differences in restless leg syndrome using a landmark-based geometric morphometric approach, considering the topographic distribution of corpus callosum for the first time.
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Affiliation(s)
- Deniz Sigirli
- Department of Biostatistics, Medicine, Bursa Uludag University , Bursa, Turkey
| | - Aygul Gunes
- Department of Neurology, Bursa Yuksek Ihtisas Education and Training Hospital, University of Health Sciences , Bursa, Turkey
| | | | - Ilker Ercan
- Department of Biostatistics, Medicine, Bursa Uludag University , Bursa, Turkey
| | - Yavuz Durmus
- Department of Radiology, Bursa Yuksek Ihtisas Education and Training Hospital, University of Health Sciences , Bursa, Turkey
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Aldemir A, Yucel K, Güven H, Kamaşak B, Dilli A, Acer N, Çomoğlu S. Structural neuroimaging findings in migraine patients with restless legs syndrome. Neuroradiology 2020; 62:1301-1313. [PMID: 32488307 DOI: 10.1007/s00234-020-02451-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/28/2020] [Indexed: 12/27/2022]
Abstract
PURPOSE One out of three migraine patients might have accompanying restless legs syndrome (RLS). In our study, we aimed to compare the volumes of the brain structures of migraineurs with and without RLS. METHODS We had 37 female patients with migraine and 17 females as the control group. Nineteen migraineurs had no RLS (RLS0) and 18 migraineurs had comorbidity of RLS (RLS1). The volumes of the brain structures were obtained by manual measurements, volBrain, and voxel-based morphometry (VBM). Manually, we measured caudate and putamen volumes. We used age, years of education, depression, anxiety scores, and total intracranial volume as covariates. RESULTS According to VBM analyses, the volumes of the left superior occipital gyrus and precuneus were increased, and the substantia nigra and cuneus were decreased in the RLS1 group compared with the RLS0 group. RLS1 patients had larger superior temporal gyrus, Brodmann area 38, and left insula, and RLS0 patients had larger Brodmann area 22, right superior temporal gyrus, and Heschl gyrus compared with controls. Migraine and RLS0 patients had a smaller corpus callosum anteriorly, whereas RLS1 patients had a smaller splenium. Caudate volumes were larger in migraine patients via the three techniques. There was a positive relation between the caudate and putamen volumes and attack frequency. CONCLUSIONS Comorbidity of RLS might be a confounding factor in structural neuroimaging studies in migraine. Deficits in the visual network seem to be related to accompanying RLS; deficits in the auditory network are particularly related to migraine.
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Affiliation(s)
- Arzu Aldemir
- Department of Neurology, Acıbadem Hospital, Eskişehir, Turkey
| | - Kaan Yucel
- Department of Anatomy, Aksaray University Medical School, Aksaray, Turkey.
| | - Hayat Güven
- Department of Neurology, Dışkapı Yıldırım Beyazıt Training and Research Hospital, University of Health Sciences, Ankara, Turkey
| | - Burcu Kamaşak
- Department of Anatomy, Ahi Evran University Medical School, Kırşehir, Turkey
| | - Alper Dilli
- Department of Radiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital, University of Health Sciences, Ankara, Turkey
| | - Niyazi Acer
- Department of Anatomy, Erciyes University Medical School, Kayseri, Turkey
| | - Selçuk Çomoğlu
- Department of Neurology, Dışkapı Yıldırım Beyazıt Training and Research Hospital, University of Health Sciences, Ankara, Turkey
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Xu Z, Han T, Li T, Zhang X, Huang Z, Zhan S, Liu C, Xu J, Wang Y. Increased Gray Matter Density and Functional Connectivity of the Pons in Restless Legs Syndrome. Nat Sci Sleep 2020; 12:221-230. [PMID: 32273784 PMCID: PMC7102916 DOI: 10.2147/nss.s239852] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 03/07/2020] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Neurophysiological and radiological studies provide accumulating evidence for the involvement of the brainstem in the pathogenesis of restless legs syndrome (RLS). The analysis of the various subregions of the brainstem may help us better understand the pathophysiological mechanisms underlying the disorder. In this study, we investigated the structural and functional changes in the various subregions of the brainstem in RLS patients. METHODS The subregional changes in gray matter density and functional connectivity in the brainstem were analyzed in 20 drug-naive idiopathic RLS patients, as well as 18 normal control (NC) subjects for comparison. Correlation analyses and multivariate pattern analyses using linear support vector machine (SVM) were conducted. RESULTS We found significantly increased gray matter density in two clusters in the pons (designated pons_1 and pons_2) and in one cluster in the midbrain in RLS patients compared with NC subjects. Further functional connectivity analyses revealed significantly decreased functional connectivity between the midbrain and the right middle occipital gyrus, between pons_1 and the right orbital part of the superior frontal gyrus, and between pons_2 and the right parahippocampus in RLS compared with NC. Moreover, the functional connectivity between pons_2 and the right supplementary motor area (SMA) was significantly increased in RLS compared with NC. This change in RLS was marginally correlated with RS_RLS scores in the RLS patients. SVM-based classification showed an AUC of 0.955 using gray matter density of pons_2, and functional connectivity between pons_2 and SMA as features. CONCLUSION Collectively, our findings suggest that changes in gray matter density and functional connectivity in the pons may play a pathologic role in RLS. Furthermore, these abnormal changes in the pons might help to discriminate RLS from healthy subjects.
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Affiliation(s)
- Zhexue Xu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, People's Republic of China.,Beijing Key Laboratory of Neuromodulation, Beijing 100053, People's Republic of China
| | - Tao Han
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, People's Republic of China.,Beijing Key Laboratory of Neuromodulation, Beijing 100053, People's Republic of China
| | - Tian Li
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China
| | - Xiaodong Zhang
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China
| | - Zhaoyang Huang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, People's Republic of China.,Beijing Key Laboratory of Neuromodulation, Beijing 100053, People's Republic of China
| | - Shuqin Zhan
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, People's Republic of China.,Beijing Key Laboratory of Neuromodulation, Beijing 100053, People's Republic of China
| | - Chunyan Liu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, People's Republic of China.,Beijing Key Laboratory of Neuromodulation, Beijing 100053, People's Republic of China
| | - Jinping Xu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China
| | - Yuping Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053, People's Republic of China.,Beijing Key Laboratory of Neuromodulation, Beijing 100053, People's Republic of China
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Lyu S, Xing H, DeAndrade MP, Perez PD, Zhang K, Liu Y, Yokoi F, Febo M, Li Y. The role of BTBD9 in the cerebral cortex and the pathogenesis of restless legs syndrome. Exp Neurol 2019; 323:113111. [PMID: 31715135 DOI: 10.1016/j.expneurol.2019.113111] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 10/09/2019] [Accepted: 11/07/2019] [Indexed: 01/18/2023]
Abstract
Restless legs syndrome (RLS) is a nocturnal neurological disorder affecting up to 10% of the population. It is characterized by an urge to move and uncomfortable sensations in the legs which can be relieved by movements. Mutations in BTBD9 may confer a higher risk of RLS. We developed Btbd9 knockout mice as an animal model. Functional alterations in the cerebral cortex, especially the sensorimotor cortex, have been found in RLS patients in several imaging studies. However, the role of cerebral cortex in the pathogenesis of RLS remains unclear. To explore this, we used in vivo manganese-enhanced MRI and found that the Btbd9 knockout mice had significantly increased neural activities in the primary somatosensory cortex (S1) and the rostral piriform cortex. Morphometry study revealed a decreased thickness in a part of S1 representing the hindlimb (S1HL) and M1. The electrophysiological recording showed Btbd9 knockout mice had enhanced short-term plasticity at the corticostriatal terminals to D1 medium spiny neurons (MSNs). Furthermore, we specifically knocked out Btbd9 in the cerebral cortex of mice (Btbd9 cKO). The Btbd9 cKO mice showed a rest-phase specific motor restlessness, decreased thermal sensation, and a thinner S1HL and M1. Both Btbd9 knockout and Btbd9 cKO exhibited motor deficits. Our results indicate that systematic BTBD9 deficiency leads to both functional and morphometrical changes of the cerebral cortex, and an alteration in the corticostriatal pathway to D1 MSNs. Loss of BTBD9 only in the cerebral cortex is sufficient to cause similar phenotypes as observed in the Btbd9 complete knockout mice.
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Affiliation(s)
- Shangru Lyu
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Hong Xing
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Mark P DeAndrade
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Pablo D Perez
- Department of Psychiatry, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Keer Zhang
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Yuning Liu
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Fumiaki Yokoi
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Marcelo Febo
- Department of Psychiatry, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Yuqing Li
- Norman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida, USA.
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Magalhães SC, Queiroz de Paiva JP, Kaelin-Lang A, Sterr A, Eckeli AL, Winkler AM, Fernandes do Prado G, Amaro E, Conforto AB. Short-interval intracortical inhibition is decreased in restless legs syndrome across a range of severity. Sleep Med 2019; 62:34-42. [PMID: 31539846 DOI: 10.1016/j.sleep.2019.03.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 03/10/2019] [Accepted: 03/12/2019] [Indexed: 01/18/2023]
Abstract
BACKGROUND Decreased short-interval intracortical inhibition (SICI) to transcranial magnetic stimulation (TMS) of the primary motor cortex was described in subjects with restless legs syndrome/Willis-Ekbom disease (RLS/WED). It remained to be determined whether the magnitude of SICI decrease would be similar across levels of RLS/WED severity. Moreover, it was unknown whether, in addition to decreases in SICI, changes in cortical thickness or area could be detected in subjects with RLS/WED compared to controls. The objective of this study was to compare SICI, cortical thickness, and cortical area in subjects with idiopathic mild to moderate RLS/WED, severe to very severe RLS/WED, and controls. METHODS The severity of RLS/WED was assessed by the International Restless Legs Syndrome Severity Scale (IRLSS). SICI and 3T magnetic resonance imaging (MRI) data of subjects with RLS/WED and controls were compared. A receiver operating characteristic curve for SICI was designed for discrimination of participants with RLS/WED from controls. Cortical thickness and area were assessed by automated surface-based analysis. RESULTS SICI was significantly reduced in patients with mild to moderate and severe to very severe RLS/WED, compared to controls (one-way analysis of variance: F = 9.62, p < 0.001). Receiver operating characteristic curve analysis predicted RLS/WED when SICI was above 35% (area under the curve = 0.79, 95% CI 0.67-0.91, p < 0.001). Analyses of the whole brain and of regions of interest did not reveal differences in gray matter thickness or area between controls and subjects with RLS/WED. CONCLUSION SICI is an accurate cortical biomarker that can support the diagnosis of RLS/WED even in subjects with mild symptoms, but cortical thickness and area were not useful for discriminating subjects with this condition from controls.
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Affiliation(s)
- Samir Câmara Magalhães
- Hospital Israelita Albert Einstein, São Paulo, SP, Brazil; Universidade de Fortaleza, Unifor, Fortaleza, CE, Brazil.
| | | | | | - Annette Sterr
- Department of Psychology, University of Surrey, Guildford, Surrey, UK
| | - Alan Luiz Eckeli
- Departamento de Neurociências e Ciências do Comportamento, Divisão de Neurologia, Hospital das Clínicas da Faculdade de Medicina da USP-Ribeirão Preto, Ribeirão Preto, SP, Brazil
| | | | | | - Edson Amaro
- Hospital Israelita Albert Einstein, São Paulo, SP, Brazil; Departamento de Radiologia, Hospital das Clínicas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Adriana Bastos Conforto
- Hospital Israelita Albert Einstein, São Paulo, SP, Brazil; Departamento de Neurologia, Hospital das Clínicas, Universidade de São Paulo, São Paulo, SP, Brazil
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Li T, Liu C, Lyu H, Xu Z, Hu Q, Xu B, Wang Y, Xu J. Alterations of Sub-cortical Gray Matter Volume and Their Associations With Disease Duration in Patients With Restless Legs Syndrome. Front Neurol 2018; 9:1098. [PMID: 30619055 PMCID: PMC6304426 DOI: 10.3389/fneur.2018.01098] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 12/03/2018] [Indexed: 01/18/2023] Open
Abstract
Object: The purpose of this study was to uncover the pathology of restless legs syndrome (RLS) by exploring brain structural alterations and their corresponding functional abnormality. Method: Surface-based morphometry (SBM) and voxel-based morphometry (VBM) were performed to explore the alterations in cortical and sub-cortical gray matter volume (GMV) in a cohort of 20 RLS and 18 normal controls (NC). Furthermore, resting-state functional connectivity (RSFC) was also performed to identify the functional alterations in patients with RLS. Results: We found significant alterations of sub-cortical GMV, especially the bilateral putamen (PUT), rather than alterations of cortical GMV in patients with RLS compared to NC using both SBM and VBM. Further sub-regional analysis revealed that GMV alterations of PUT was mostly located in the left dorsal caudal PUT in patients with RLS. In addition, altered RSFC patterns of PUT were identified in patients with RLS compared to NC. Moreover, correlation analyses showed that the GMV of the left caudate and the left ventral rostral PUT were positively correlated with disease duration in patients with RLS. Conclusions: The alterations of subcortical GMV might imply that the primarily affected areas are located in sub-cortical areas especially in the sub-region of PUT by the pathologic process of RLS, which might be used as potential biomarkers for the early diagnosis of RLS.
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Affiliation(s)
- Tian Li
- Department of Psychology, Faculty of Education, Hubei University, Wuhan, China.,Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Chunyan Liu
- Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neuromodulation, Beijing, China
| | - Hanqing Lyu
- Radiology Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Zhexue Xu
- Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neuromodulation, Beijing, China
| | - Qingmao Hu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Bibo Xu
- Department of Psychology, Faculty of Education, Hubei University, Wuhan, China
| | - Yuping Wang
- Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neuromodulation, Beijing, China
| | - Jinping Xu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
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15
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Yang FC, Chou KH, Lee PL, Yin JH, Chen SY, Kao HW, Sung YF, Chou CH, Tsai CK, Tsai CL, Lin CP, Lee JT. Patterns of gray matter alterations in migraine and restless legs syndrome. Ann Clin Transl Neurol 2018; 6:57-67. [PMID: 30656184 PMCID: PMC6331309 DOI: 10.1002/acn3.680] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 09/29/2018] [Accepted: 10/01/2018] [Indexed: 01/18/2023] Open
Abstract
Objectives Migraine and restless legs syndrome (RLS) are often comorbid and share elements of pathology; however, their neuroanatomical underpinnings are poorly understood. This study aimed to identify patterns of gray matter volume (GMV) alteration specific to and common among patients with RLS, migraine, and comorbid migraine and RLS. Methods High‐resolution T1‐weighted images were acquired from 116 subjects: 27 RLS patients, 22 migraine patients, 22 patients with comorbid migraine and RLS, and 45 healthy controls. Direct group comparisons and conjunction analysis were first used to localize the distinct and shared neural signatures of migraine and RLS. We also investigated whether the shared neural signature could be replicated in an additional comorbid migraine/RLS group. Results Compared with healthy controls, migraine patients showed GMV changes in the lateral occipital cortex, cerebellum, frontal pole, and middle frontal gyrus (MFG), and RLS patients showed GMV changes in the thalamus, middle temporal gyrus, anterior cingulate cortex, insular cortex, and MFG. In migraine, compared with RLS, GMV differences were found in the precuneus, lateral occipital and occipital fusiform cortex, superior frontal and precentral gyri, and cerebellum. Conjunction analyses for these disorders showed altered GMV in the MFG, also found in patients with comorbid migraine and RLS. The GMV of the MFG also correlated with sleep quality in patients with comorbid migraine and RLS. Interpretation Migraine and RLS are characterized by shared and distinctive neuroanatomical characteristics, with a specific role of the MFG. These findings may be related to shared pathophysiology of these two distinct disorders.
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Affiliation(s)
- Fu-Chi Yang
- Department of Neurology Tri-Service General Hospital National Defense Medical Center Taipei Taiwan
| | - Kun-Hsien Chou
- Brain Research Center National Yang-Ming University Taipei Taiwan.,Institute of Neuroscience National Yang-Ming University Taipei Taiwan
| | - Pei-Lin Lee
- Department of Biomedical Imaging and Radiological Sciences National Yang-Ming University Taipei Taiwan
| | - Jiu-Haw Yin
- Department of Neurology Tri-Service General Hospital National Defense Medical Center Taipei Taiwan.,Division of Neurology Department of Medicine Cheng Hsin General Hospital Taipei Taiwan
| | - Shao-Yuan Chen
- Department of Neurology Cardinal Tien Hospital New Taipei City Taiwan.,Department of Hyperbaric Medicine Cardinal Tien Hospital New Taipei City Taiwan.,School of Medicine Fu-Jen Catholic University New Taipei City Taiwan
| | - Hung-Wen Kao
- Department of Radiology Tri-Service General Hospital National Defense Medical Center Taipei Taiwan
| | - Yueh-Feng Sung
- Department of Neurology Tri-Service General Hospital National Defense Medical Center Taipei Taiwan
| | - Chung-Hsing Chou
- Department of Neurology Tri-Service General Hospital National Defense Medical Center Taipei Taiwan.,Graduate Institute of Medical Sciences National Defense Medical Center Taipei Taiwan
| | - Chia-Kuang Tsai
- Department of Neurology Tri-Service General Hospital National Defense Medical Center Taipei Taiwan
| | - Chia-Lin Tsai
- Department of Neurology Tri-Service General Hospital National Defense Medical Center Taipei Taiwan
| | - Ching-Po Lin
- Brain Research Center National Yang-Ming University Taipei Taiwan.,Institute of Neuroscience National Yang-Ming University Taipei Taiwan.,Department of Biomedical Imaging and Radiological Sciences National Yang-Ming University Taipei Taiwan.,Institute of Brain Science National Yang-Ming University Taipei Taiwan
| | - Jiunn-Tay Lee
- Department of Neurology Tri-Service General Hospital National Defense Medical Center Taipei Taiwan.,Graduate Institute of Medical Sciences National Defense Medical Center Taipei Taiwan
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Lee BY, Kim J, Connor JR, Podskalny GD, Ryu Y, Yang QX. Involvement of the central somatosensory system in restless legs syndrome. Neurology 2018; 90:e1834-e1841. [DOI: 10.1212/wnl.0000000000005562] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 02/23/2018] [Indexed: 01/18/2023] Open
Abstract
ObjectiveTo investigate morphologic changes in the somatosensory cortex and the thickness of the corpus callosum subdivisions that provide interhemispheric connections between the 2 somatosensory cortical areas.MethodsTwenty-eight patients with severe restless legs syndrome (RLS) symptoms and 51 age-matched healthy controls were examined with high-resolution MRI at 3.0 tesla. The vertex-wise analysis in conjunction with a novel cortical surface classification method was performed to assess the cortical thickness across the whole-brain structures. In addition, the thickness of the midbody of the corpus callosum that links postcentral gyri in the 2 hemispheres was measured.ResultsWe demonstrated that a morphologic change occurred in the brain somatosensory system in patients with RLS compared to controls. Patients with RLS exhibited a 7.5% decrease in average cortical thickness in the bilateral postcentral gyrus (p < 0.0001). Accordingly, there was a substantial decrease in the corpus callosum posterior midbody (p < 0.008) wherein the callosal fibers are connected to the postcentral gyrus, suggesting altered white matter properties in the somatosensory pathway.ConclusionOur results provide in vivo evidence of morphologic changes in the primary somatosensory system, which could be responsible for the sensory functional symptoms of RLS. These results provide a better understanding of the pathophysiology underlying the RLS sensory symptoms and could lead to a potential imaging marker for RLS.
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Affiliation(s)
- Tadaaki Mano
- From the Gifu University of Medical Science (T.M.), Seki, Gifu, Japan; and Division of Pulmonary, Critical Care & Sleep (R.J.T.), Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA.
| | - Robert J Thomas
- From the Gifu University of Medical Science (T.M.), Seki, Gifu, Japan; and Division of Pulmonary, Critical Care & Sleep (R.J.T.), Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA
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19
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Abstract
Several studies provide information useful to our understanding of restless legs syndrome (RLS), using various imaging techniques to investigate different aspects putatively involved in the pathophysiology of RLS, although there are discrepancies between these findings. The majority of magnetic resonance imaging (MRI) studies using iron-sensitive sequences supports the presence of a diffuse, but regionally variable low brain-iron content, mainly at the level of the substantia nigra, but there is increasing evidence of reduced iron levels in the thalamus. Positron emission tomography (PET) and single positron emission computed tomography (SPECT) findings mainly support dysfunction of dopaminergic pathways involving not only the nigrostriatal but also mesolimbic pathways. None or variable brain structural or microstructural abnormalities have been reported in RLS patients; reports are slightly more consistent concerning levels of white matter. Most of the reported changes were in regions belonging to sensorimotor and limbic/nociceptive networks. Functional MRI studies have demonstrated activation or connectivity changes in the same networks. The thalamus, which includes different sensorimotor and limbic/nociceptive networks, appears to have lower iron content, metabolic abnormalities, dopaminergic dysfunction, and changes in activation and functional connectivity. Summarizing these findings, the primary change could be the reduction of brain iron content, which leads to dysfunction of mesolimbic and nigrostriatal dopaminergic pathways, and in turn to a dysregulation of limbic and sensorimotor networks. Future studies in RLS should evaluate the actual causal relationship among these findings, better investigate the role of neurotransmitters other than dopamine, focus on brain networks by connectivity analysis, and test the reversibility of the different imaging findings following therapy.
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Affiliation(s)
- Giovanni Rizzo
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy; Unit of Neurology, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
| | - Xu Li
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA; Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sebastiano Galantucci
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Massimo Filippi
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy; Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Yong Won Cho
- Department of Neurology, School of Medicine, Dongsan Medical Center, Keimyung University, Daegu, South Korea.
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Koo BB, Bagai K, Walters AS. Restless Legs Syndrome: Current Concepts about Disease Pathophysiology. Tremor Other Hyperkinet Mov (N Y) 2016; 6:401. [PMID: 27536462 PMCID: PMC4961894 DOI: 10.7916/d83j3d2g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 06/07/2016] [Indexed: 01/31/2023]
Abstract
Background In the past few decades, much has been learned about the pathophysiology of restless legs syndrome (RLS). Investigators have studied neuropathology, imaging, electrophysiology, and genetics of RLS, identifying brain regions and biological systems affected in RLS. This manuscript will review RLS pathophysiology literature, examining the RLS state through consideration of the neuroanatomy, then the biological, organ, and genetic systems. Methods Pubmed (1966 to April 2016) was searched for the term “restless legs syndrome” cross-referenced with “pathophysiology,” “pathogenesis,” “pathology,” or “imaging.” English language papers were reviewed. Studies that focused on RLS in relation to another disease were not reviewed. Results Although there are no gross structural brain abnormalities in RLS, widespread brain areas are activated, including the pre- and post-central gyri, cingulate cortex, thalamus, and cerebellum. Pathologically, the most consistent finding is striatal iron deficiency in RLS patients. A host of other biological systems are also altered in RLS, including the dopaminergic, oxygen-sensing, opioid, glutamatergic, and serotonergic systems. Polymorphisms in genes including BTBD9 and MEIS1 are associated with RLS. Discussion RLS is a neurologic sensorimotor disorder that involves pathology, most notably iron deficiency, in motor and sensory brain areas. Brain areas not subserving movement or sensation such as the cingulate cortex and cerebellum are also involved. Other biological systems including the dopaminergic, oxygen-sensing, opioid, glutamatergic, and serotonergic systems are involved. Further research is needed to determine which of these anatomic locations or biological systems are affected primarily, and which are affected in a secondary response.
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Affiliation(s)
- Brian B Koo
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA; Department of Neurology, Connecticut Veterans Affairs Health System, West Haven, CT, USA; Yale Center for Neuroepidemiology & Clinical Neurological Research, New Haven, CT, USA
| | - Kanika Bagai
- Department of Neurology, Vanderbilt University, Nashville, TN, USA
| | - Arthur S Walters
- Department of Neurology, Vanderbilt University, Nashville, TN, USA
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Gorges M, Rosskopf J, Müller HP, Lindemann K, Hornyak M, Kassubek J. Patterns of increased intrinsic functional connectivity in patients with restless legs syndrome are associated with attentional control of sensory inputs. Neurosci Lett 2016; 617:264-9. [PMID: 26921454 DOI: 10.1016/j.neulet.2016.02.043] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 02/22/2016] [Accepted: 02/23/2016] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Potential alterations of intrinsic functional connectivity in idiopathic restless legs syndrome (RLS) are to be assumed since RLS is considered a network disorder. Whole-brain-based investigation of intrinsic functional connectivity networks including the sensorimotor systems in patients with RLS was compared with matched healthy controls. METHODS 'Resting-state' functional MRI (1.5 T) from 26 patients with RLS and 26 matched controls were analyzed using standardized seed-based analysis procedures. The motor/sensorimotor, sensory thalamic, ventral and dorsal attention, basal ganglia-thalamic, cingulate, and brainstem networks were used for voxel-based group comparisons between RLS patients and controls. RESULTS Significantly increased connectivities were observed in the sensory thalamic, ventral and dorsal attention, basal ganglia-thalamic, and cingulate networks in RLS patients, whereas no differences could be demonstrated for the motor/sensorimotor and the brainstem system. The pattern of functional connectivity alterations was positively correlated with increasing symptom severity. CONCLUSIONS Abnormally increased regional BOLD synchronization appears to be a key feature of intrinsic brain architecture in RLS. Alterations in cortical and sub-cortical functional networks support the notion that the underlying pathophysiology of RLS is beyond the sensorimotor and the brainstem system and may be also associated with altered attentional control of sensory inputs.
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Affiliation(s)
- Martin Gorges
- Department of Neurology, University of Ulm, Ulm, Germany
| | | | | | | | - Magdolna Hornyak
- Department of Neurology, University of Ulm, Ulm, Germany; Neuropsychiatry Centre Erding/München, Erding, Germany
| | - Jan Kassubek
- Department of Neurology, University of Ulm, Ulm, Germany.
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22
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Belke M, Heverhagen JT, Keil B, Rosenow F, Oertel WH, Stiasny-Kolster K, Knake S, Menzler K. DTI and VBM reveal white matter changes without associated gray matter changes in patients with idiopathic restless legs syndrome. Brain Behav 2015; 5:e00327. [PMID: 26442748 PMCID: PMC4589804 DOI: 10.1002/brb3.327] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 01/26/2015] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND AND PURPOSE We evaluated cerebral white and gray matter changes in patients with iRLS in order to shed light on the pathophysiology of this disease. METHODS Twelve patients with iRLS were compared to 12 age- and sex-matched controls using whole-head diffusion tensor imaging (DTI) and voxel-based morphometry (VBM) techniques. Evaluation of the DTI scans included the voxelwise analysis of the fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD). RESULTS Diffusion tensor imaging revealed areas of altered FA in subcortical white matter bilaterally, mainly in temporal regions as well as in the right internal capsule, the pons, and the right cerebellum. These changes overlapped with changes in RD. Voxel-based morphometry did not reveal any gray matter alterations. CONCLUSIONS We showed altered diffusion properties in several white matter regions in patients with iRLS. White matter changes could mainly be attributed to changes in RD, a parameter thought to reflect altered myelination. Areas with altered white matter microstructure included areas in the internal capsule which include the corticospinal tract to the lower limbs, thereby supporting studies that suggest changes in sensorimotor pathways associated with RLS.
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Affiliation(s)
- Marcus Belke
- Department of Neurology, Philipps-University MarburgBaldingerstrasse, Marburg, 35043, Germany
| | - Johannes T Heverhagen
- Department of Diagnostic Radiology, Philipps-University MarburgBaldingerstrasse, Marburg, 35043, Germany
| | - Boris Keil
- Department of Diagnostic Radiology, Philipps-University MarburgBaldingerstrasse, Marburg, 35043, Germany
| | - Felix Rosenow
- Department of Neurology, Philipps-University MarburgBaldingerstrasse, Marburg, 35043, Germany
- Epilepsy Center Franfurt Rhein-Main, Department of Neurology, Johann Wolfgang Goethe UniversityFrankfurt am Main, Germany
| | - Wolfgang H Oertel
- Department of Neurology, Philipps-University MarburgBaldingerstrasse, Marburg, 35043, Germany
| | - Karin Stiasny-Kolster
- Department of Neurology, Philipps-University MarburgBaldingerstrasse, Marburg, 35043, Germany
- Somnomar, Institute for Medical Research and Sleep Medicine MarburgMarburger Strasse 9a, Marburg, 35043, Germany
| | - Susanne Knake
- Department of Neurology, Philipps-University MarburgBaldingerstrasse, Marburg, 35043, Germany
| | - Katja Menzler
- Department of Neurology, Philipps-University MarburgBaldingerstrasse, Marburg, 35043, Germany
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Abstract
Restless leg syndrome/Willis-Ekbom disease has brain iron deficiency that produces excessive dopamine and known genetic risks, some of which contribute to the brain iron deficiency. Dopamine treatments work temporarily but may eventually produce further postsynaptic down-regulation and worse restless leg syndrome. This article includes sections focused on pathophysiologic findings from each of these areas: genetics, cortical-spinal excitability, and iron and dopamine.
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Affiliation(s)
- Richard P Allen
- Department of Neurology, Johns Hopkins University, Asthma & Allergy Building, 1B76b, 5501 Hopkins Bayview Boulevard, Baltimore, MD 21224, USA.
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Abstract
Neuroimaging studies are of crucial relevance in defining the pathophysiology of restless legs syndrome (RLS). MRI studies showed no structural brain lesions and confirmed a central iron deficiency. Structural and functional studies showed an involvement of the thalamus, sensorimotor cortical areas, and cerebellum in RLS and assessed neurotransmission abnormalities in the dopaminergic and opiate systems. Finally, glutamatergic hyperactivity has been proposed as a cause of disrupted and shortened sleep in RLS. Differences among the results of the studies make it difficult to draw any definitive conclusions, thus, suggesting the need for future research.
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Affiliation(s)
- Federica Provini
- Department of Biomedical and Neuromotor Sciences, Bellaria Hospital, University of Bologna, Via Altura 3, Bologna 40139, Italy; IRCCS Institute of Neurological Sciences of Bologna, Bologna, Italy.
| | - Giacomo Chiaro
- Department of Biomedical and Neuromotor Sciences, Bellaria Hospital, University of Bologna, Via Altura 3, Bologna 40139, Italy
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Pan P, Dai Z, Shang H, Xiao P, Dong C, Song W, Zhou G, Zhong J, Shi H. Gray matter anomalies in anterior cingulate cortex as a correlate of depressive symptoms in drug-naïve idiopathic restless legs syndrome. Neuroscience 2014; 277:1-5. [DOI: 10.1016/j.neuroscience.2014.06.045] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 06/19/2014] [Accepted: 06/19/2014] [Indexed: 01/18/2023]
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Chang Y, Chang HW, Song H, Ku J, Earley CJ, Allen RP, Cho YW. Gray matter alteration in patients with restless legs syndrome: a voxel-based morphometry study. Clin Imaging 2015; 39:20-5. [PMID: 25176196 DOI: 10.1016/j.clinimag.2014.07.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 06/27/2014] [Accepted: 07/22/2014] [Indexed: 01/18/2023]
Abstract
The purpose of this study was to demonstrate whether or not restless legs syndrome (RLS) is associated with any morphological change in gray matter. Forty-six RLS subjects and 46 controls were enrolled. We performed voxel-based morphometry analysis and compared the results of the two groups. The RLS subjects showed significant regional decreases of gray matter volume in the left hippocampal gyrus, both parietal lobes, medial frontal areas and cerebellum (uncorrected, P<.001). We found that RLS patients showed structural alteration in the brain and alterations in certain parts of the brain in RLS patients are relevant to RLS.
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Chang Y, Paik JS, Lee HJ, Chang HW, Moon HJ, Allen RP, Earley CJ, Cho YW. Altered white matter integrity in primary restless legs syndrome patients: diffusion tensor imaging study. Neurol Res 2014; 36:769-74. [PMID: 24620984 DOI: 10.1179/1743132814y.0000000336] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
OBJECTIVES A prior diffusion tensor imaging (DTI) of restless legs syndrome (RLS) subjects found alterations in brain white matter (WM). The aim of this study was to explore the possible mechanism of altered integrity of brain WM in RLS patients. METHODS The DTI measurement was performed in 22 subjects with RLS and 22 age-matched control subjects. Using a voxel-based analysis, fractional anisotropy (FA) and axial and radial diffusivities (AD and RD) were compared between RLS and control subjects with a two-sample t-test, and correlation analysis was performed in RLS subjects. RESULTS RLS subjects demonstrated decreased FA in the genu of the corpus callosum and frontal WM adjacent to the inferior frontal gyrus compared with the control subjects. For areas of decreased FA, both the AD and RD were higher than that in the control subjects. DISCUSSION Our findings suggest that loss of axonal density and myelin may account for WM changes seen in a prior study of RLS subjects.
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Rizzo G, Tonon C, Manners D, Testa C, Lodi R. Imaging Brain Functional and Metabolic Changes in Restless Legs Syndrome. Curr Neurol Neurosci Rep 2013; 13. [DOI: 10.1007/s11910-013-0372-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Rizzo G, Tonon C, Testa C, Manners D, Vetrugno R, Pizza F, Marconi S, Malucelli E, Provini F, Plazzi G, Montagna P, Lodi R. Abnormal medial thalamic metabolism in patients with idiopathic restless legs syndrome. Brain 2012. [PMID: 23183234 DOI: 10.1093/brain/aws266] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Pathophysiology of restless legs syndrome is poorly understood. A role of the thalamus, specifically of its medial portion which is a part of the limbic system, was suggested by functional magnetic resonance imaging and positron emission tomography studies. The aim of this study was to evaluate medial thalamus metabolism and structural integrity in patients with idiopathic restless legs syndrome using a multimodal magnetic resonance approach, including proton magnetic resonance spectroscopy, diffusion tensor imaging, voxel-based morphometry and volumetric and shape analysis. Twenty-three patients and 19 healthy controls were studied in a 1.5 T system. Single voxel proton magnetic resonance spectra were acquired in the medial region of the thalamus. In diffusion tensor examination, mean diffusivity and fractional anisotropy were determined at the level of medial thalamus using regions of interest delineated to outline the same parenchyma studied by spectroscopy. Voxel-based morphometry was performed focusing the analysis on the thalamus. Thalamic volumes were obtained using FMRIB's Integrated Registration and Segmentation Tool software, and shape analysis was performed using the FMRIB Software Library tools. Proton magnetic resonance spectroscopy study disclosed a significantly reduced N-acetylaspartate:creatine ratio and N-acetylaspartate concentrations in the medial thalamus of patients with restless legs syndrome compared with healthy controls (P < 0.01 for both variable). Lower N-acetylaspartate concentrations were significantly associated with a family history of restless legs syndrome (β = -0.49; P = 0.018). On the contrary, diffusion tensor imaging, voxel-based morphometry and volumetric and shape analysis of the thalami did not show differences between the two groups. Proton magnetic resonance spectroscopic findings in patients with restless legs syndrome indicate an involvement of medial thalamic nuclei of a functional nature; however, the other structural techniques of the same region did not show any changes. These findings support the hypothesis that dysfunction of the limbic system plays a role in the pathophysiology of idiopathic restless legs syndrome.
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Affiliation(s)
- Giovanni Rizzo
- Department of Internal Medicine, Aging and Nephrology, University of Bologna, Via Massarenti 9, 40138 Bologna, Italy
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Margariti PN, Astrakas LG, Tsouli SG, Hadjigeorgiou GM, Konitsiotis S, Argyropoulou MI. Investigation of unmedicated early onset restless legs syndrome by voxel-based morphometry, T2 relaxometry, and functional MR imaging during the night-time hours. AJNR Am J Neuroradiol 2011; 33:667-72. [PMID: 22173758 DOI: 10.3174/ajnr.a2829] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND AND PURPOSE The pathophysiology of eRLS has not yet been elucidated. The purpose of the study was to assess, in patients with eRLS, the volume, iron content, and activation of the brain during night-time episodes of SLD and PLMs. MATERIALS AND METHODS Eleven right-handed unmedicated patients with eRLS (mean age, 55.3 ± 8.4 years; disease duration, 17.5 ± 14.05 years) and 11 matched control subjects were studied with a T1-weighted high-resolution 3D spoiled gradient-echo sequence used for VBM and a multisection spin-echo T2-weighted sequence used for T2 relaxometry. Additionally, a single-shot multisection gradient echo-planar sequence was used for fMRI. Brain activation was recorded during spontaneous SLD and PLMs. SPM software was used for analysis of the functional data. RESULTS The patients showed no regional brain volume change, but T2 relaxometry revealed decreased T2 relaxation time in the right globus pallidus internal and the STN, indicating increased iron content. The patients were observed to activate the following areas: in the left hemisphere, the primary motor and somatosensory cortex, the thalamus, the pars opercularis, and the ventral anterior cingulum; and in the right hemisphere, the striatum, the inferior and superior parietal lobules, and the dorsolateral prefrontal cortex. Bilateral activation was observed in the cerebellum, the midbrain, and the pons. CONCLUSIONS eRLS is associated with increased iron content of the globus pallidus internal and STN, suggesting dysfunction of the basal ganglia. Activation of the striatofrontolimbic area may represent the neurofunctional substrate mediating the repetitive compulsive movements seen in RLS.
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Affiliation(s)
- P N Margariti
- Department of Radiology, Medical School, University of Ioannina, Ioannina, Greece
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