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Objective. To investigate the relationship between magnetization transfer imaging (MTI), diffusionweighted imaging (DWI), proton magnetic resonance spectroscopy (H-MRS), and T2 relaxometry findings in patients with primary neuropsychiatric systemic lupus erythematosus (NPSLE).Methods. Conclusion. The selected study parameters represent different biologic features in the human brain and can be informative with regard to different pathologic processes in NPSLE. The demonstrated associations between MTI, DWI, H-MRS, and T2 data in patients with a history of NPSLE suggest that there is one pathogenesis and/or common neuropathologic outcome in NPSLE despite differences in clinical presentation.The pathophysiologic processes in primary neuropsychiatric systemic lupus erythematosus (NPSLE) are unknown. Whereas secondary NPSLE can be traced to SLE-related causes such as infection, drug side effects, hypertension, or metabolic derangements, primary NPSLE is a diagnosis of exclusion (1). The heterogeneity of the clinical signs and symptoms in primary NPSLE suggests heterogeneity in the underlying pathophysiologic processes. In patients with primary NPSLE, imaging with conventional techniques often fails to demonstrate abnormalities that provide an explanation for the clinical signs and symptoms (2).Recently, brain abnormalities in patients with primary NPSLE were demonstrated by magnetization transfer imaging (MTI) (3,4). In other studies, abnormalities in otherwise normal-appearing brain tissue of patients with primary NPSLE have been found using diffusion-weighted imaging (DWI) (5), proton magnetic resonance spectroscopy (H-MRS) (6-8), and T2 relaxometry (9,10). To date it is not known whether findings with these different advanced quantitative magnetic Dr.

Objective. To investigate the relationship between quantitative estimates of global brain damage based on magnetization transfer imaging (MTI) and cerebral functioning, as measured by neurologic, psychiatric, and cognitive assessments, as well as disease duration in patients with a history of neuropsychiatric systemic lupus erythematosus (NPSLE).Methods. In patients with systemic lupus erythematosus (SLE), neurologic, psychiatric, and psychological symptoms often occur. The frequency of nervous system involvement has been reported to range from 11% to 60% (1). Infection, drug side effects, hypertension, or metabolic derangements, as well as an intrinsic brain manifestation of SLE (i.e., neuropsychiatric SLE [NPSLE]), can cause such symptoms. The uncertain pathogenesis and the wide variety of manifestations of NPSLE complicate the development of a uniform diagnostic decision-making protocol and a uniform method of monitoring a patient with this type of SLE. Findings of routine brain imaging studies are often unremarkable in patients with NPSLE, or the studies reveal abnormalities, such as cerebral atrophy and white matter hyperintensities (on magnetic resonance imaging [MRI]), that can also be found in SLE patients without neuropsychiatric symptoms. Furthermore, no correlation has thus far been demonstrated between quantitative measures of such nonspecific abnormalities and measures of brain function (2-5).Recently, magnetization transfer ratio (MTR) histogram analysis, a quantitative MRI technique based on magnetization transfer imaging (MTI), was applied in patients with primary NPSLE but without abnormalities on MRI that could account for the clinical picture. With this technique, cerebral abnormalities were identified in these patients (6,7). Such abnormalities were found in SLE patients who had had episodes of neuropsychiatric symptoms in the past (chronic NPSLE) as well as in patients who were experiencing an active phase of neuropsychiatric symptoms (active NPSLE) (6,7). The

Objective. Damage of brain parenchyma in patients with primary diffuse neuropsychiatric systemic lupus erythematosus (NPSLE) has been indicated by magnetization transfer imaging (MTI). However, the location of MTI abnormalities is unknown. This study was undertaken to assess the distribution of MTI abnormalities over gray matter (GM) and white matter (WM) in SLE patients with a history of NP symptoms without explanatory magnetic resonance imaging (MRI) evidence of focal disease.Methods. MTI was performed in 24 female SLE patients with a history of diffuse NP symptoms and 24 healthy female controls. Magnetization transfer ratio (MTR) maps were calculated for GM and WM separately, and GM and WM MTR histograms were generated. Univariate and multivariate analyses with age as an additional covariate were performed on the histogram parameters peak location (PL), peak height (PH), and mean MTR.Results. Compared with controls, significantly reduced PH (mean ؎ SD 136 ؎ 22 arbitrary units versus 151 ؎ 13 arbitrary units) and mean MTR (33.3 ؎ 1.0 percent units versus 33.6 ؎ 0.5 percent units) were found in the GM of NPSLE patients (P ‫؍‬ 0.002 and P ‫؍‬ 0.033, respectively, in multivariate analyses). No significant differences were observed for WM MTR parameters.Conclusion. This is the first study to demonstrate, using MTI, that in SLE patients with a history of NP symptoms and without explanatory focal abnormalities on MRI, the GM is particularly affected. These findings support the hypothesis that neuronal injury may underlie central nervous system manifestations in NPSLE.Up to 75% of patients with systemic lupus erythematosus (SLE) experience neuropsychiatric symptoms indicative of central nervous system (CNS) involvement. In primary neuropsychiatric SLE (NPSLE), these NP manifestations are attributed to the SLE disease process itself, rather than to secondary factors such as infections or metabolic disorders (1). Focal neurologic NP syndromes are often associated with antiphospholipid antibodies; however, the cause of diffuse neurologic and psychiatric symptoms is largely unknown (2). Findings of conventional magnetic resonance imaging (MRI) of the brain are frequently unremarkable, and abnormalities are nonspecific (3,4). However, quantitative MRI techniques, such as magnetization transfer imaging (MTI), diffusion-weighted imaging, and MR spectroscopy (MRS), are now being assessed for their diagnostic value (4).Using MTI, a quantitative MRI technique that is sensitive to both macroscopic and microscopic CNS damage (4), abnormalities that had been invisible by conventional MRI were demonstrated in the brain parenchyma of NPSLE patients (5). Significant associations with parameters of neurologic, psychiatric, and neuropsychological function demonstrated the clinical relevance of these findings (6). Although the underlying pathogenesis of diffuse brain damage in NPSLE is largely unknown, recent findings of neuronal and astrocytic degradation products in the cerebrospinal fluid (CSF) of SLE patients have focused attention...

Objective. The clinical symptoms of neuropsychiatric systemic lupus erythematosus (NPSLE) are usually reversible, but whether the associated brain damage is also reversible is still a matter of debate. Since magnetization transfer imaging (MTI) is more sensitive than conventional magnetic resonance imaging (MRI) in demonstrating brain damage, it has become a useful tool in the detection and quantification of diffuse brain disorders such as multiple sclerosis. In this study, MTI was applied to investigate whether central nervous system (CNS) damage is present in patients with a history of NPSLE.Methods. Eleven female patients with a history of NPSLE and no previous or concurrent primary neurologic or psychiatric disease (ages 17-49 years), 11 female patients with SLE without a history of NPSLE (non-NPSLE; ages 15-51 years), and 10 healthy female controls (ages 17-47 years) underwent MTI. From these MTI scans, quantitative data on the uniformity of the brain parenchyma and atrophy were derived.Results. One NPSLE and 1 non-NPSLE patient were excluded from this study due to infarctions detected with conventional MRI. MTI measures normalized for intracranial volume, reflecting abnormalities of the brain parenchyma as well as atrophy, were lower (P < 0.001) in the NPSLE group than in both control groups. A higher (P < 0.005) mean ratio of cerebrospinal fluid to intracranial volume, indicative of atrophy, was present in the NPSLE group compared with either the non-NPSLE patients or healthy controls. Still, the MTI measures solely reflecting uniformity of the brain parenchyma (normalized for brain volume) were also significantly (P < 0.001) lower in the NPSLE patients than in both control groups.Conclusion. This study demonstrates that using MTI, CNS damage can be demonstrated in patients with a history of NPSLE. MTI might, therefore, be an alternative and sensitive tool to detect brain injury in NPSLE, and might also be useful in studying the natural history of the disease.The clinical symptoms of diffuse neuropsychiatric systemic lupus erythematosus (NPSLE) are usually reversible, but it is unknown whether the underlying brain disorder is also reversible. Although punctate areas of increased signal (PAIS) or atrophy can be found in NPSLE patients with the use of diagnostic imaging techniques, these characteristics are also demonstrated in SLE patients who do not have NPSLE (1). Still, functional imaging techniques have demonstrated a variety of abnormalities that are found strictly in NPSLE patients (2-10). Some of the results have suggested transient abnormalities, whereas others have indicated lasting damage.Magnetization transfer imaging (MTI) is a magnetic resonance imaging (MRI) technique that has 2 advantages over conventional MRI: it seems to be more sensitive to structural brain damage, and it permits easy and robust quantification of such structural damage (11). MTI has been applied as a method to detect and quantify diffuse diseases of the brain, such as multiple sclerosis (MS). In MS patients, MTI estimates...

Objective. Tumor necrosis factor ␣ 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.

Our results indicate that volumetric MTI analysis detects cerebral changes in the active phase of NPSLE. The abnormalities in the brain parenchyma of patients with chronic NPSLE produced MTI values that were the same as those in patients with inactive MS. MTI values in the active phase of NPSLE differed from those in the chronic phase, which might reflect the presence of inflammation. These preliminary results suggest that MTI might provide evidence for the presence of active NPSLE. MTI might also prove to be a valuable technique for monitoring treatment trials.

The short-term results from the multicenter RAPID randomized controlled trial indicate that the Legflow PEB is safe and feasible for the treatment of intermediate to long SFA lesions. In this trial, at least 70% of the patients suffered an occlusion. The PEB group had higher rates of primary patency and freedom from CD-TLR, although there were no statistically significant differences vs controls.