Proton magnetic resonance spectroscopy may predict future brain lesions in SLE patients: a functional multi-imaging approach and follow up

Different patterns of cerebral perfusion in SLE patients with and without neuropsychiatric manifestations

To investigate brain perfusion patterns in systemic lupus erythematosus (SLE) patients with and without neuropsychiatric systemic lupus erythematosus (NPSLE and non-NPSLE, respectively) and to identify biomarkers for the diagnosis of NPSLE using noninvasive three-dimensional (3D) arterial spin labeling (ASL). Thirty-one NPSLE and 24 non-NPSLE patients and 32 age- and sex-matched normal controls (NCs) were recruited. Three-dimensional ASL-MRI was applied to quantify cerebral perfusion. Whole brain, gray (GM) and white matter (WM), and voxel-based analysis (VBA) were performed to explore perfusion characteristics. Correlation analysis was performed to find the relationship between the perfusion measures, lesion volumes, and clinical variables. Receiver operating characteristic (ROC) analysis and support vector machine (SVM) classification were applied to differentiate NPSLE patients from non-NPSLE patients and healthy controls. Compared to NCs, NPSLE patients showed increased cerebral blood flow (CBF) within WM but decreased CBF within GM, while non-NPSLE patients showed increased CBF within both GM and WM. Compared to non-NPSLE patients, NPSLE patients showed significantly reduced CBF in the frontal gyrus, cerebellum, and corpus callosum. CBF within several brain regions such as cingulate and corpus callosum showed significant correlations with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and the Systemic Lupus International Collaborating Clinics (SLICC) damage index scores. ROC analysis showed moderate performance in distinguishing NPSLE from non-NPSLE patients with AUCs > 0.7, while SVM analysis demonstrated that CBF within the corpus callosum achieved an accuracy of 83.6% in distinguishing NPSLE from non-NPSLE patients. Different brain perfusion patterns were observed between NPSLE and non-NPSLE patients. CBF measured by noninvasive 3D ASL could be a useful biomarker for the diagnosis and disease monitoring of NPSLE and non-NPSLE patients.

Cerebral functional deficits in patients with ankylosing spondylitis- an fMRI study

Neurological impairment plays an important role in the development of Ankylosing spondylitis (AS). Early diagnosis and detection of it may stop the progress of neurological complications and improve the quality of patients' lives greatly. Somatosensory evoked potential (SSEP) and magnetic motor evoked potentials (MEP) have been proved useful to detect neurological impairments of AS. This study aimed to investigate the cerebral function deficits of AS using functional MRI technology. Twenty seven patients with AS and 28 control subjects were included in this study. All of them underwent structural MRI and resting state-functional MRI (rs-fMRI) scanning. Comparisons of amplitude of low frequency fluctuations (ALFF) of rs-fMRI signals between AS patients and normal controls were performed using two sample t-tests. To examine functional connectivity within the groups, one-sample t tests were performed on the individual z-value maps. The z values were compared between the two groups using two-sample t test. Partial correlations between rs-fMRI measures (ALFF and functional connectivity) of the brain regions which showed group difference and clinical results including the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score, the serum high-sensitivity C-reactive protein (hsCRP), and the erythrocyte sedimentation rate (ESR) were analyzed for AS patients. Compared with normal controls, the AS patients exhibited significant lower ALFF in the left medial frontal gyrus, the right precentral gyrus and the right posterior cingulate, while higher ALFF in the left cerebellum anterior lobe, the left middle temporal gyrus, the left superior occipital gyrus, the left postcentral gyrus and the right precuneus. AS patients showed widespread brain connectivity alterations. Functional connectivity strength of the left precuneus and the left middle temporal gyrus were closely correlated with the the BASDAI scores, ESR and hsCRP in AS patients. Our results enhance the understanding of the pathomechanism of AS and suggest that Rs-fMRI may be a helpful tool in the clinical detection and evaluation of neurological impairment in AS.

Longitudinal evaluation of diffusion tensor imaging and cognition in systemic lupus erythematosus

Objective

This pilot study aimed to examine longitudinal changes in brain structure and function in patients with systemic lupus erythematosus (SLE) using diffusion tensor imaging (DTI) and neuropsychological testing.

Methods

Fifteen female SLE patients with no history of major neuropsychiatric (NP) manifestations had brain magnetic resonance imaging (MRI) with DTI at baseline and approximately 1.5 years later. At the same time points, a standardized battery of cognitive tests yielding a global cognitive impairment index (CII) was administered. At baseline, the SLE patients had mean age of 34.0 years (SD = 11.4), mean education of 14.9 years (SD = 2.1), and mean disease duration of 121.5 months (SD = 106.5). The MRI images were acquired with a 3T GE MRI scanner. A DTI sequence with 33 diffusion directions and b-value of 800 s/mm2 was used. Image acquisition time was about 10 minutes.

Results

No significant change in cognitive dysfunction (from the CII) was detected. Clinically evaluated MRI scans remained essentially unchanged, with 62% considered normal at both times, and the remainder showing white matter (WM) hyperintensities that remained stable or resolved. DTI showed decreased fractional anisotropy (FA) and increased mean diffusivity (MD) in bilateral cerebral WM and gray matter (GM) with no major change in NP status, medical symptoms, or medications over time. Lower FA was found in the following regions: left and right cerebral WM, and in GM areas including the parahippocampal gyrus, thalamus, precentral gyrus, postcentral gyrus, angular gyrus, parietal lobe, and cerebellum. Greater MD was found in the following regions: left and right cerebral WM, frontal cortex, left cerebral cortex, and the putamen.

Conclusions

This is the first longitudinal study of DTI and cognition in SLE, and results disclosed changes in both WM and GM without cognitive decline over an 18-month period. DTI abnormalities in our participants were not associated with emergent NP activity, medical decline, or medication changes, and the microstructural changes developed in the absence of macrostructural abnormalities on standard MRI. Microstructural changes may relate to ongoing inflammation, and the stability of cognitive function may be explained by medical treatment, the variability of NP progression in SLE, or the impact of cognitive reserve.

A Conscious Resting State fMRI Study in SLE Patients Without Major Neuropsychiatric Manifestations

Neuropsychiatric systemic lupus erythematosus (NPSLE) is one of the main causes of death in patients with systemic lupus erythematosus (SLE). Signs and symptoms of NPSLE are heterogeneous, and it is hard to diagnose, and treat NPSLE patients in the early stage. We conducted this study to explore the possible brain activity changes using resting state functional magnetic resonance imaging (rs-fMRI) in SLE patients without major neuropsychiatric manifestations (non-NPSLE patients). We also tried to investigate the possible associations among brain activity, disease activity, depression, and anxiety. In our study, 118 non-NPSLE patients and 81 healthy controls (HC) were recruited. Rs-fMRI data were used to calculate the regional homogeneity (ReHo) in all participants. We found decreased ReHo values in the fusiform gyrus and thalamus and increased ReHo values in the parahippocampal gyrus and uncus. The disease activity was positively correlated with ReHo values of the cerebellum and negatively correlated with values in the frontal gyrus. Several brain areas showed correlations with depressive and anxiety statuses. These results suggested that abnormal brain activities might occur before NPSLE and might be the foundation of anxiety and depression symptoms. Early detection and proper treatment of brain dysfunction might prevent the progression to NPSLE. More studies are needed to understand the complicated underlying mechanisms.

Advanced MRI techniques: biomarkers in neuropsychiatric lupus

Objectives

The objective of this study was to determine whether advanced MRI could provide biomarkers for diagnosis and prognosis in neuropsychiatric systemic lupus erythematosus (NPSLE).

Methods

Our prospective study included 28 systemic lupus erythematosus (SLE) patients with primary central NPSLE, 22 patients without NPSLE and 20 healthy controls. We used visual scales to evaluate atrophy and white matter hyperintensities, voxel-based morphometry and Freesurfer to measure brain volume, plus diffusion-tensor imaging (DTI) to assess white matter (WM) and gray matter (GM) damage. We compared the groups and correlated MRI abnormalities with clinical data.

Results

NPSLE patients had less GM and WM than controls ( p = 0.042) in the fronto-temporal regions and corpus callosum. They also had increased diffusivities in the temporal lobe WM ( p < 0.010) and reduced fractional anisotropy in the right frontal lobe WM ( p = 0.018). High clinical scores, longstanding disease, and low serum C3 were associated with atrophy, lower fractional anisotropy and higher diffusivity in the fronto-temporal lobes. Antimalarial treatment correlated negatively with atrophy in the frontal cortex and thalamus; it was also associated with lower diffusivity in the fronto-temporal WM clusters.

Conclusions

Atrophy and microstructural damage in fronto-temporal WM and GM in NPSLE correlate with severity, activity and the time from disease onset. Antimalarial treatment seems to give some brain-protective effects.

A neurometabolite study of chronic daily headache in patients with systemic lupus erythematosus using magnetic resonance spectroscopy: comparison with fibromyalgia patients and healthy controls

BACKGROUND/AIMS

Neuropsychiatric systemic lupus erythematosus (SLE) includes a broad spectrum of neurologic and psychiatric manifestations. One of the most commonly observed neuropsychiatric symptoms is headache. However, the lack of specific clinical distinctions for headache in SLE has made it difficult to elucidate its pathophysiology. The aim of this study is to evaluate the neurometabolic changes using Proton Magnetic Resonance Spectroscopy (¹H-MRS) in patients with SLE who suffer from chronic daily headache (CDH).

METHODS

SLE and fibromyalgia patients with CDH and healthy controls were recruited (n = 9, n = 5, and n = 6, respectively). ¹H-MRS metabolite ratios were evaluated in bilateral basal ganglia (BG) and bilateral peritrigonal white matter (PWM).

RESULTS

¹H-MRS showed a significantly decreased N-acetylaspartate (NAA)/creatine (Cr) ratio in right BG in SLE patients with CDH compared to fibromyalgia patients with CDH and normal controls (p = 0.029 and p = 0.020, respectively). Left PWM NAA/Cr and choline/Cr ratios in SLE patients with CDH were lower than those in fibromyalgia patients with CDH (p = 0.019 and p = 0.029, respectively).

CONCLUSIONS

This study suggests the possibility that CDH in patients with SLE might be associated with neuronal dysfunction and neurometabolic changes.

The diagnosis and clinical management of the neuropsychiatric manifestations of lupus

Neuropsychiatric (NP) involvement in Systemic Lupus Erythematosus (SLE), can be a severe and troubling manifestation of the disease that heavily impacts patient's health, quality of life and disease outcome. It is one of the most complex expressions of SLE which can affect central, peripheral and autonomous nervous system. Complex interrelated pathogenetic mechanisms, including genetic factors, vasculopathy, vascular occlusion, neuroendocrine-immune imbalance, tissue and neuronal damage mediated by autoantibodies, inflammatory mediators, blood brain barrier dysfunction and direct neuronal cell death can be all involved. About NPSLE a number of issues are still matter of debate: from classification and burden of NPSLE to attribution and diagnosis. The role of neuroimaging and new methods of investigation still remain pivotal and rapidly evolving as well as is the increasing knowledge in the pathogenesis. Overall, two main pathogenetic pathways have been recognized yielding different clinical phenotypes: a predominant ischemic-vascular one involving large and small blood vessels, mediated by aPL, immune complexes and leuko-agglutination which it is manifested with more frequent focal NP clinical pictures and a predominantly inflammatory-neurotoxic one mediated by complement activation, increased permeability of the BBB, intrathecal migration of autoantibodies, local production of immune complexes and pro-inflammatory cytokines and other inflammatory mediators usually appearing as diffuse NP manifestations. In the attempt to depict a journey throughout NPSLE from diagnosis to a reasoned therapeutic approach, classification, epidemiology, attribution, risk factors, diagnostic challenges, neuroimaging techniques and pathogenesis will be considered in this narrative review based on the most relevant and recent published data.

Central pathways causing fatigue in neuro-inflammatory and autoimmune illnesses

BACKGROUND

The genesis of severe fatigue and disability in people following acute pathogen invasion involves the activation of Toll-like receptors followed by the upregulation of proinflammatory cytokines and the activation of microglia and astrocytes. Many patients suffering from neuroinflammatory and autoimmune diseases, such as multiple sclerosis, Parkinson's disease and systemic lupus erythematosus, also commonly suffer from severe disabling fatigue. Such patients also present with chronic peripheral immune activation and systemic inflammation in the guise of elevated proinflammtory cytokines, oxidative stress and activated Toll-like receptors. This is also true of many patients presenting with severe, apparently idiopathic, fatigue accompanied by profound levels of physical and cognitive disability often afforded the non-specific diagnosis of chronic fatigue syndrome.

DISCUSSION

Multiple lines of evidence demonstrate a positive association between the degree of peripheral immune activation, inflammation and oxidative stress, gray matter atrophy, glucose hypometabolism and cerebral hypoperfusion in illness, such as multiple sclerosis, Parkinson's disease and chronic fatigue syndrome. Most, if not all, of these abnormalities can be explained by a reduction in the numbers and function of astrocytes secondary to peripheral immune activation and inflammation. This is also true of the widespread mitochondrial dysfunction seen in otherwise normal tissue in neuroinflammatory, neurodegenerative and autoimmune diseases and in many patients with disabling, apparently idiopathic, fatigue. Given the strong association between peripheral immune activation and neuroinflammation with the genesis of fatigue the latter group of patients should be examined using FLAIR magnetic resonance imaging (MRI) and tested for the presence of peripheral immune activation.

SUMMARY

It is concluded that peripheral inflammation and immune activation, together with the subsequent activation of glial cells and mitochondrial damage, likely account for the severe levels of intractable fatigue and disability seen in many patients with neuroimmune and autoimmune diseases.This would also appear to be the case for many patients afforded a diagnosis of Chronic Fatigue Syndrome.

Twenty-year brain magnetic resonance imaging follow-up study in Systemic Lupus Erythematosus: Factors associated with accrual of damage and central nervous system involvement

To evaluate the long-term progression of cerebral MRI abnormalities in patients with longstanding SLE, 30 patients (age 53.5 ± 11.3) underwent brain MRI at baseline (b-MRI) and after 19.4 ± 3.7 years of follow-up (fu-MRI). Two neuroradiologists visually analyzed the MRIs comparing: 1) white matter hyperintensities (WMHIs), 2) cerebral volume, and 3) parenchymal defects; these outcomes were also built in a modified MRI scoring system (mMSS) to estimate the cumulative parenchymal damage. The independent risk factors for accrual of MRI brain damage, as well as the association between MRI abnormalities and the development of new neuropsychiatric (NP) manifestations classified according to the 1999 ACR case definition were also analyzed. Twenty-three patients (76.7%) showed worsening of mMSS; 19 (63.3%) had increased number and volume of WMHIs, 8 (26.7%) had significant cerebral volume loss, and 6 (20%) showed new ischemic parenchymal lesions. Only 6 patients had normal MRI. Antimalarial agents (p=0.006; OR 0.08) were protective against worsening of WMHIs. High cumulative dose of corticosteroids (p=0.026; OR 8.8) and dyslipidemia (p=0.044; OR 10.1) were associated with increased mMSS and cerebral volume loss, respectively. Higher mMSS score at baseline was independently associated with worsening of WMHIs (p=0.001; OR 5.7) and development of new NP events (p=0.019; OR 2.0); higher load of deep WMHIs at b-MRI (p=0.018; OR 2.0) was independently associated with stroke risk. This study shows that MRI brain damage in SLE patients progresses independently from NP involvement as effect of potentially modifiable risk factors and it is associated with increased risk of new NP events.

Increased myo-inositol in parietal white and gray matter as a biomarker of poor prognosis in neuropsychiatric lupus: a case report

Neuropsychiatric manifestations can be a serious complication of systemic lupus erythematosus, affecting nearly 56% of these patients. Frequently, acceptable clinical outcome is observed in neurolupus with immunosuppressive therapy. Different metabolites identified with MR spectroscopy may be associated with modifications in the natural history of this disease, specifically in the central nervous system. We report a case of neurolupus with progressive neurologic impairment despite aggressive immunosuppressive treatment. We describe clinical features, laboratory and MRI results, as well as characteristic findings on MR spectroscopy. Serial MRI identified atrophy of the left temporal lobe. MR spectroscopy showed an increase of myo-inositol/creatine ratio intensity, accompanied by a decrease of N-acetylaspartate/creatine ratio in both parietal white and gray matter. During follow-up, the patient developed progressive cognitive deficiency despite the intensification of therapy. Neurolupus manifestations are common and immunosuppressive treatment often avoids severe complications. Characteristic findings on MR spectroscopy may be useful for clinicians to determine poor prognosis and resistance to therapy.

In vivo evaluation of brain damage in the course of systemic lupus erythematosus using magnetic resonance spectroscopy, perfusion-weighted and diffusion-tensor imaging

Twenty-two neuropsychiatric (NPSLE) and 13 systemic lupus erythematosus (SLE) patients with a normal appearing brain on plain magnetic resonance (MR) as well as 20 age-matched healthy controls underwent MR spectroscopy (MRS), perfusion-weighted (PWI) and diffusion-tensor imaging (DTI). In MRS NAA/Cr, Cho/Cr and mI/Cr ratios were calculated from the posterior cingulate cortex and left parietal white matter. In PWI, values of cerebral blood volume (CBV) were assessed from 14 regions, including gray and white matter. In DTI fractional anisotropy (FA) values were obtained from 14 white matter tracts including projection, commissural and association fibers. All MR measurements were correlated with clinical data. SLE and NPSLE patients showed significantly (p < 0.05) lower NAA/Cr ratios within both evaluated regions and FA values within the cingulum, as well as a tendency to cortical hypoperfusion. Compared to SLE, NPSLE subjects revealed lower FA values within a wide range of association fibers and corpus callosum. Advanced MR techniques are capable of in vivo detection of complex microstructural brain damage in SLE and NPSLE subjects regarding neuronal loss, mild hypoperfusion and white matter disintegrity. MRS and DTI seem to show the highest usefulness in depicting early changes in normal appearing gray and white matter in SLE patients.

Effect of autoimmune diseases on cognitive function

The location of both autoimmune processes and other causes of brain inflammation is important in determining the impact of inflammation on brain function. This chapter focuses on autoimmune and infectious diseases leading to inflammatory brain disease resulting in cognitive defects with a special focus on systemic lupus erythematosus (SLE). Collectively called neuropsychiatric SLE (NPSLE), NPSLE occurs in 20-95% of pediatric patients with SLE (pSLE). The incidence of cognitive dysfunction is difficult to ascertain in pediatric patients as few studies have been performed. Using formal neurocognitive testing of unselected pediatric SLE patients, the rate of cognitive abnormalities was approximately 50% and impairment was associated with longer disease duration in one study. A second small study showed global depression on performance and academic scores while a larger study using a neuropsychiatric inventory showed a 55% rate of dysfunction. These diverging findings may result from the lack of a standardized cognitive assessment battery. The Childhood Arthritis and Rheumatology Research Alliance (CARRA) group of pediatric rheumatologists proposed a 2 hour 40 minutes battery for assessment of cognitive testing of SLE patients from age 9 to 18 years. Further assessments using this battery should provide a better neurocognitive profile of pSLE.

Neuropsychiatric systemic lupus erythematosus

Neuropsychiatric systemic lupus erythematosus (NPSLE) is the least understood, yet perhaps the most prevalent manifestation of lupus. The pathogenesis of NPSLE is multifactorial and involves various inflammatory cytokines, autoantibodies, and immune complexes resulting in vasculopathic, cytotoxic and autoantibody-mediated neuronal injury. The management of NPSLE is multimodal and has not been subjected to rigorous study. Different treatment regimens include nonsteroidal anti-inflammatory drugs, anticoagulation, and immunosuppressives such as cyclophosphamide, azathioprine, mycophenolate mofetil, and methotrexate. For refractory NPSLE, intravenous immunoglobulin (IVIG), plasmapheresis, and rituximab have been used. Adjunctive symptomatic treatment complements these therapies by targeting mood disorders, psychosis, cognitive impairment, seizures or headaches. Several new biological agents are being tested including Belimumab, a human monoclonal antibody that targets B lymphocyte stimulator. This review focuses on the pathophysiology, treatment, and new potential therapies for neuropsychiatric manifestations of systemic lupus erythematosus.

Maintaining brain health by monitoring inflammatory processes: a mechanism to promote successful aging

Maintaining brain health promotes successful aging. The main determinants of brain health are the preservation of cognitive function and remaining free from structural and metabolic abnormalities, including loss of neuronal synapses, atrophy, small vessel disease and focal amyloid deposits visible by neuroimaging. Promising studies indicate that these determinants are to some extent modifiable, even among adults seventy years and older. Converging animal and human evidence further suggests that inflammation is a shared mechanism, contributing to both cognitive decline and abnormalities in brain structure and metabolism. Thus, inflammation may provide a target for intervention. Specifically, circulating inflammatory markers have been associated with declines in cognitive function and worsening of brain structural and metabolic characteristics. Additionally, it has been proposed that older brains are characterized by a sensitization to neuroinflammatory responses, even in the absence of overt disease. This increased propensity to central inflammation may contribute to poor brain health and premature brain aging. Still unknown is whether and how peripheral inflammatory factors directly contribute to decline of brain health. Human research is limited by the challenges of directly measuring neuroinflammation in vivo. This review assesses the role that inflammation may play in the brain changes that often accompany aging, focusing on relationships between peripheral inflammatory markers and brain health among well-functioning, community-dwelling adults seventy years and older. We propose that monitoring and maintaining lower levels of systemic and central inflammation among older adults could help preserve brain health and support successful aging. Hence, we also identify plausible ways and novel experimental study designs of maintaining brain health late in age through interventions that target the immune system.

Repeated brain conventional MRI and SPECT evaluation in systemic lupus erythematosus patients with and without neuropsychiatric involvement: a follow up study

Objectives: To assess the utility of a combined neuroimaging approach in the follow up of patients affected by systemic lupus erythematosus (SLE) with and without neuropsychiatric (NP) involvement. Methods: Patients who underwent a first combined brain conventional magnetic resonance imaging (cMRI) and single photon emission computed tomography (SPECT) and later repeated the same examinations between 2001 and 2008 were retrieved from a large database. Clinical and neuroimaging data were analysed and their relationships evaluated at baseline and at follow up. Results: Fifty SLE patients (38 with and 12 without NP involvement, mean age 36.8 yrs and mean disease duration at first instrumental evaluation 5.5 yrs) were enrolled. At baseline, the majority of them had a diffuse pattern of NP involvement. After a mean follow up period of 4 years all patients repeated neuroimaging and clinical evaluation. In 23 patients (22 with and 1 without NP manifestations at baseline) a new NP event occurred. Overall, neuroimaging remained unchanged or improved, but in some cases it worsened. No correlations were found between instrumental findings and clinical picture. Conclusions: In this study, the clinical features at baseline appeared to be a better predictor of future NP events than morphological and functional neuroimaging. Therefore the utility of repeating a combined instrumental evaluation (cMRI and SPECT) may be debatable especially for patients with diffuse NP involvement where the decision to perform serial combined neuroimaging examinations should be carefully assessed and based mainly on clinical judgement. Lupus (2011) 20, 1387–1395.

Cognitive dysfunction and white matter abnormalities in systemic lupus erythematosus

Brain abnormalities have been documented by neuropsychological assessment as well as a variety of neuroimaging techniques in patients with systemic lupus erythematosus (SLE). Conventional neuroimaging in patients with neuropsychiatric disease (NPSLE) typically discloses periventricular white matter (WM) hyperintensities, infarcts, hemorrhages, and cerebral atrophy. In SLE patients with none of these findings, sophisticated neuroimaging techniques have recently supported associations between microstructural WM abnormalities and abnormal attention, executive function, and processing speed. This mild cognitive dysfunction in SLE (MCD-SLE), which may result from early myelinopathy, precedes the more severe cognitive dysfunction of NPSLE, related to more obvious WM and neuronal damage.

Localization of cerebral functional deficits in patients with non-neuropsychiatric systemic lupus erythematosus

Neuropsychiatric systemic lupus erythematosus (NP-SLE) is a common complication of systemic lupus erythematosus (SLE), and clinical interventions are of only limited efficacy despite relatively high prevalence. Such complications have been studied extensively, but the pathoetiology of NP-SLE has not yet been elucidated. Diagnosis of NP-SLE focuses primarily on psychological manifestations, and the underlying mechanisms leading to neuropsychiatric complications remain unknown. To address potential changes in brain function before NP-SLE development, we used resting-state functional magnetic resonance imaging (MRI) to compare regional brain activity in SLE patients versus matched controls. We report that regional activity in cerebellum and in areas of the default mode network are attenuated in patients with SLE, and moreover individual alterations in cerebellar activity correlated positively with the disease activity index. These findings provide direct evidence that significant alteration of brain function, resembling that observed in patients with NP-SLE, is already present in SLE patients without neuropsychiatric complications, highlighting the need for early evaluation and intervention in SLE patients. Furthermore, the disease activity rating correlated with regional functional alterations in the cerebellum, suggesting that the cerebellum could play a role in the pathogenesis of NP-SLE.

Elevated cerebral blood flow and volume in systemic lupus measured by dynamic susceptibility contrast magnetic resonance imaging

OBJECTIVE

Studies that have examined abnormalities in cerebral blood flow (CBF) in patients with systemic lupus erythematosus (SLE) reported CBF relative to a region assumed to be normal in the brain. We examined the absolute differences in both regional CBF and cerebral blood volume (CBV) between patients with SLE and healthy controls.

METHODS

CBF and CBV were measured with dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI), a technique that provides an alternative to radionuclide perfusion studies and permits quantitative anatomic, CBF, and CBV imaging in a single scanning session. CBF and CBV were measured in lesions and in normal-appearing tissue in the major cerebral and subcortical brain regions. Unlike most perfusion studies in SLE, CBF and CBV values were not normalized to a region of the brain assumed to be healthy.

RESULTS

CBF and CBV within MRI-visible lesions were markedly reduced relative to surrounding normal-appearing white matter. CBF and CBV in normal-appearing tissue were both higher in SLE patient groups, with or without lesions, relative to the control group.

CONCLUSION

DSC MRI, without normalization to a region presumed to be healthy, revealed that CBF and CBV in normal-appearing tissue in patients with SLE was higher than CBF and CBV in controls. Since this finding was made in subgroups of patients with and without lesions, the higher CBF and CBV appear to precede lesion pathology.

Brain involvement in rheumatoid arthritis: a magnetic resonance spectroscopy study

OBJECTIVE

Tumor necrosis factor alpha was recently implicated as an important mediator of communication between the peripheral and cerebral immune systems in an animal model of chronic inflammation. The purpose of this study was to examine by proton magnetic resonance spectroscopy ((1)H-MRS) the influence of inflammation on cerebral metabolism in patients with rheumatoid arthritis (RA).

METHODS

Single-voxel (1)H-MRS of the centrum semiovale was performed on 35 RA patients (6 men and 29 women; mean +/- SD age 51.8 +/- 14.6 years) and 28 healthy age- and sex-matched control subjects (9 men and 19 women; mean +/- SD age 50.2 +/- 10.4 years). None of the study subjects had any neurologic signs or symptoms. Clinical markers of disease activity were correlated with the (1)H-MRS findings.

RESULTS

Patients with active RA, as reflected by an elevated erythrocyte sedimentation rate (ESR), had a significantly higher ratio of choline to creatine and a significantly lower ratio of N-acetylaspartate to choline than did patients with inactive RA, as reflected by a normal ESR. Moreover, the ratios of choline to creatine and NAA to choline were significantly correlated with the ESR after correction for age, sex, smoking status, handedness, alcohol consumption, medication use, and disease duration. Medication use had no additional effect on these associations.

CONCLUSION

Our data show that systemic inflammation in RA is associated with metabolic changes in the brain.

Magnetic resonance spectroscopic imaging detects abnormalities in normal-appearing frontal lobe of patients with Sturge-Weber syndrome

BACKGROUND

In Sturge-Weber syndrome (SWS), structural MRI abnormalities are most common in the posterior brain regions. Frontal lobe involvement increases the risk of motor impairment. The goal of this study was to determine whether Magnetic Resonance Spectroscopic Imaging (MRSI) can improve detection of frontal lobe involvement in children with SWS.

METHODS

Sixteen children (age: .9-10.4 years) with unilateral SWS underwent MRI with MRSI prospectively. N-acetyl-aspartate (NAA) and choline asymmetries in the posterior and frontal regions were measured.

RESULTS

Eight children presented normal-appearing frontal lobes on conventional MRI, but 7 of them showed abnormal NAA and/or choline content in the frontal lobe of the affected hemisphere. Lower frontal lobe gray matter NAA was associated with earlier onset of seizures (r= .76; P= .04) and impaired motor function (r=-.89, P < .001). Frontal NAA asymmetry was an independent predictor of motor function in a regression analysis (P= .01)

CONCLUSION

MRSI is more sensitive than conventional structural MRI for detection of frontal lobe involvement in SWS. Decreased frontal lobe NAA is an excellent predictor of motor functions. Thus, MRSI can provide complementary information for the assessment of normal-appearing brain regions, and may assist prognosis evaluation in children with SWS.

Quantitative magnetic resonance imaging analyses and clinical significance of hyperintense white matter lesions in systemic lupus erythematosus patients

OBJECTIVE

To analyze the clinical significance of hyperintense white matter (WM) lesions in both symptomatic and asymptomatic systemic lupus erythematosus (SLE) patients.

METHODS

We studied 120 consecutive SLE patients and 44 healthy volunteers. Fluid attenuated inversion recovery and T2-weighted magnetic resonance images (MRI) were used for visual and semiautomatic volumetric measurements.

RESULTS

At baseline, 61 MRI were normal and 59 had hyperintense WM lesions. Mean volumes of WM lesions were 96.14 (SD = 85.14) mm(3) in T2 weighted and 197.2 (161.13) mm(3) in FLAIR images. The volume of WM lesions was associated with age (r = 0.45; p = 0.01), total corticosteroid dose (r = 0.53; p = 0.001), and Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index scores (r = 0.55; p = 0.002). After a median follow-up time of 24 months (SD = 2.3; range = 12-28 months), 20 patients had still normal MRIs, 30 patients had stable MRI findings, and 30 had new WM lesions. Predictors for new or increased WM lesions were past central nervous system manifestations (p = 0.001; OR = 12.2; 95% CI = 3.5-21.2), antiphospholipid antibodies (p = 0.003; OR = 6.9; 95% CI = 2.1-15.3); Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index scores (p = 0.002; OR = 7.2; 95% CI = 1.4-17.8) and higher dose of total corticosteroid dose (p = 0.01; OR = 2.4; 95% CI = 1.4-6.7).

CONCLUSION

Small hyperintense WM lesions in SLE are associated with central nervous system symptoms and antiphospholipid antibodies, and progress over time in patients with more severe SLE. Therefore, in the context of SLE, these lesions are likely consequences of central nervous system damage and not mere incidental finding.

Neurometabolic changes in normal white matter may predict appearance of hyperintense lesions in systemic lupus erythematosus

To determine if neurometabolic changes in the white matter (WM) of systemic lupus erythematosus (SLE) patients may predict the appearance of small hyperintense lesions on T2-weighted magnetic resonance imaging (MRI) inside the magnetic resonance spectroscopy (MRS) region of interest (ROI). We included 30 SLE patients and 23 controls. We performed single voxel proton MRS over the superior-posterior region of the corpus callosum. We measured signals from N-acetyl-compounds (NAA), choline (Cho) and creatine-phosphocreatin (Cr) and determined NAA/Cr and Cho/Cr ratios. After a minimum of 12 months, MRI and MRS were repeated in all patients and nine volunteers. Twenty patients had normal MRI and 10 patients had MRI hyperintense lesions in the MRS ROI at baseline. All patients had hyperintense lesions in the MRS ROI in follow-up MRIs. All SLE patients had increased Cho/Cr values at both MRS when compared with normal controls (P = 0.001). In addition, there was an increase in Cho/Cr values when patients' baseline and follow-up MRS were compared (P = 0.001). We observed a correlation between Cho/Cr ratios and number of WM lesions (r = 0.69; P = 0.001). Increased Cho/Cr in normal appearing WM may be indicative of future appearance of hyperintense T2-weighted MRI lesions in SLE patients.

Evidence of reversible axonal dysfunction in systemic lupus erythematosus: a proton MRS study

Our objective was to investigate axonal dysfunction in patients with systemic lupus erythematosus (SLE) using proton magnetic resonance spectroscopy (1H-MRS). We studied prospectively 90 SLE patients (mean age of 32.5 years) and 23 normal volunteers (mean age of 33.8 years). We performed single voxel proton MRS using point resolved spectroscopy sequence over the superior-posterior region of the corpus callosum. We measured signals from N-acetyl compounds [N-acetylaspartate (NAA)] at 2.01 p.p.m., choline-based compounds (Cho) at 3.2 p.p.m. and creatine and phosphocreatine containing compounds (Cr) at 3.0 p.p.m. and determined NAA/Cr ratios. After 12 months, MRI and MRS were repeated in 50 patients and 9 volunteers. Patients were divided according to disease activity (measured by SLE disease activity index) during initial and follow-up MRS. We performed paired t-test and ANOVA with Tukey's post hoc comparisons to evaluate group differences. At study entry, 29 patients had active SLE with involvement of central nervous system (CNS) and 28 patients had active SLE without CNS manifestations. A total of 14 patients had inactive SLE with past CNS presentation, and 19 had inactive SLE without history of CNS involvement. NAA/Cr ratios were significant lower in patients with active SLE, independently of CNS involvement, when compared with patients with inactive SLE (P = 0.005) and controls (P = 0.01). We observed a significant increase in NAA/Cr ratio in 15 patients who had active SLE at initial MRS and inactive SLE at follow-up (P = 0.04). In 10 patients with active SLE both at initial and at follow-up MRS we observed a reduction in NAA/Cr ratio (P = 0.02). By contrast, there was a significant reduction of NAA/Cr ratio in 15 patients who had inactive SLE at initial MRS and active SLE at follow-up (P = 0.001). In 10 patients with inactive SLE both at initial and at follow-up MRS NAA/Cr ratio did not change (P = 0.2). This study shows evidence of axonal dysfunction in patients with active SLE, independently of CNS manifestations that may be reversible, at least in part, during periods of inactivity of disease.