| 1. |
- Cagnoli, Patricia C, et al.
(författare)
-
Changes in Regional Brain Morphology in Neuropsychiatric Systemic Lupus Erythematosus.
- 2012
-
Ingår i: Journal of Rheumatology. - : The Journal of Rheumatology. - 0315-162X .- 1499-2752. ; 39:5, s. 959-967
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Neuropsychiatric lupus (NPSLE) is a severe and potentially life-threatening condition, reported to occur in 25%-70% of patients with systemic lupus erythematosus (SLE). Brain imaging, especially magnetic resonance imaging, is frequently used to diagnose or exclude overt cerebral pathologies such as edema, hemorrhage, and central thrombosis. More advanced imaging techniques have been applied to demonstrate subtle changes in regional cerebral blood flow and brain structure. We investigated changes in regional gray-matter (GM) volume in SLE patients without neurological manifestations and NPSLE patients at an acute stage of the disease. METHODS: Using high-resolution structural images and voxel-based morphometry (VBM), we investigated regional GM volume in 20 NPSLE patients (within 2 weeks of the acute manifestation), 18 SLE patients without neurologic and/or psychiatric manifestations, and 18 healthy controls. RESULTS: VBM analyses revealed several regions of GM atrophy in various parts of the brain in NPSLE and SLE patients. GM atrophy was seen in both groups in the temporal and parietal lobes and was most pronounced in the posterior thalamus bilaterally. Both groups showed an increase in regional GM volume in the posterior parahippocampal gyrus. CONCLUSION: Our data suggest that changes in regional brain morphology are present in acute NPSLE, but also in SLE (as compared to controls), which might be indicative of a subclinical neurodegenerative process. Further research is needed to investigate whether specific neuropsychiatric symptoms are related to these changes.
|
|
| 2. |
- Foerster, Bradley R., et al.
(författare)
-
Reduced insular gamma-aminobutyric acid in fibromyalgia
- 2012
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 64:2, s. 579-583
-
Tidskriftsartikel (refereegranskat)abstract
- Objective Recent scientific findings have reinvigorated interest in examining the role of gamma-aminobutyric acid (GABA), the major inhibitory central nervous system neurotransmitter, in chronic pain conditions. Decreased inhibitory neurotransmission is a proposed mechanism in the pathophysiology of chronic pain syndromes such as fibromyalgia (FM). The purpose of this study was to test the hypothesis that decreased levels of insular and anterior cingulate GABA would be present in FM patients, and that the concentration of this neurotransmitter would be correlated with pressurepain thresholds. Methods. Sixteen FM patients and 17 age-and sex-matched healthy controls underwent pressure-pain testing and a 3T proton magnetic resonance spectroscopy session in which the right anterior insula, right posterior insula, anterior cingulate, and occipital cortex were examined in subjects at rest. Results. GABA levels in the right anterior insula were significantly lower in FM patients compared with healthy controls (mean +/- SD 1.17 +/- 0.24 arbitrary institutional units versus 1.42 +/- 0.32 arbitrary institutional units; P = 0.016). There was a trend toward increased GABA levels in the anterior cingulate of FM patients compared with healthy controls (P = 0.06). No significant differences between groups were detected in the posterior insula or occipital cortex (P > 0.05 for all comparisons). Within the right posterior insula, higher levels of GABA were positively correlated with pressurepain thresholds in the FM patients (Spearman's rho = 0.63; P = 0.02). Conclusion. Diminished inhibitory neurotransmission resulting from lower concentrations of GABA within the right anterior insula may play a role in the pathophysiology of FM and other central pain syndromes.
|
|
| 3. |
- Harris, Richard E, et al.
(författare)
-
Pregabalin rectifies aberrant brain chemistry, connectivity, and functional response in chronic pain patients.
- 2013
-
Ingår i: Anesthesiology. - 1528-1175. ; 119:6, s. 1453-1464
-
Tidskriftsartikel (refereegranskat)abstract
- Chronic pain remains a significant challenge for modern health care as its pathologic mechanisms are largely unknown and preclinical animal models suffer from limitations in assessing this complex subjective experience. However, human brain neuroimaging techniques enable the assessment of functional and neurochemical alterations in patients experiencing chronic pain and how these factors may dynamically change with pharmacologic treatment.
|
|
| 4. |
- Ichesco, Eric, et al.
(författare)
-
Altered Functional Connectivity Between the Insula and the Cingulate Cortex in Patients With Temporomandibular Disorder: A Pilot Study.
- 2012
-
Ingår i: Headache. - : Wiley. - 1526-4610. ; 52, s. 441-454
-
Tidskriftsartikel (refereegranskat)abstract
- Background.- Among the most common chronic pain conditions, yet poorly understood, are temporomandibular disorders (TMDs), with a prevalence estimate of 3-15% for Western populations. Although it is increasingly acknowledged that central nervous system mechanisms contribute to pain amplification and chronicity in TMDs, further research is needed to unravel neural correlates that might abet the development of chronic pain. Objective.- The insular cortex (IC) and cingulate cortex (CC) are both critically involved in the experience of pain. The current study sought specifically to investigate IC-CC functional connectivity in TMD patients and healthy controls (HCs), both during resting state and during the application of a painful stimulus. Methods.- Eight patients with TMD, and 8 age- and sex-matched HCs were enrolled in the present study. Functional magnetic resonance imaging data during resting state and during the performance of a pressure pain stimulus to the temple were acquired. Predefined seed regions were placed in the IC (anterior and posterior insular cortices) and the extracted signal was correlated with brain activity throughout the whole brain. Specifically, we were interested whether TMD patients and HCs would show differences in IC-CC connectivity, both during resting state and during the application of a painful stimulus to the face. Results.- As a main finding, functional connectivity analyses revealed an increased functional connectivity between the left anterior IC and pregenual anterior cingulate cortex (ACC) in TMD patients, during both resting state and applied pressure pain. Within the patient group, there was a negative correlation between the anterior IC-ACC connectivity and clinical pain intensity as measured by a visual analog scale. Conclusions.- Since the pregenual region of the ACC is critically involved in antinociception, we hypothesize that an increase in anterior IC-ACC connectivity is indicative of an adaptation of the pain modulatory system early in the chronification process.
|
|
| 5. |
- Khatami, Mohammad, et al.
(författare)
-
BundleMAP : Anatomically localized classification, regression, and hypothesis testing in diffusion MRI
- 2017
-
Ingår i: Pattern Recognition. - : Elsevier BV. - 0031-3203. ; 63, s. 593-600
-
Tidskriftsartikel (refereegranskat)abstract
- Diffusion MRI (dMRI) provides rich information on the white matter of the human brain, enabling insight into neurological disease, normal aging, and neuroplasticity. We present BundleMAP, an approach to extracting features from dMRI data that can be used for supervised classification, regression, and hypothesis testing. Our features are based on aggregating measurements along nerve fiber bundles, enabling visualization and anatomical interpretation. The main idea behind BundleMAP is to use the ISOMAP manifold learning technique to jointly parametrize nerve fiber bundles. We combine this idea with mechanisms for outlier removal and feature selection to obtain a practical machine learning pipeline. We demonstrate that it increases accuracy of disease detection and estimation of disease activity, and that it improves the power of statistical tests.
|
|
| 6. |
- Schmidt-Wilcke, Tobias, et al.
(författare)
-
Diminished white matter integrity in patients with systemic lupus erythematosus.
- 2014
-
Ingår i: NeuroImage: Clinical. - : Elsevier BV. - 2213-1582. ; 5, s. 291-297
-
Tidskriftsartikel (refereegranskat)abstract
- Systemic lupus erythematosus (SLE) is an autoimmune connective tissue disease that can affect the central nervous system. Neuropsychiatric symptoms are found in 25-70% of patients. Using diffusion tensor imaging (DTI) various studies have reported changes in white matter integrity in SLE patients with neuropsychiatric symptoms (NPSLE patients). The purpose of this study was to investigate, if regional changes in white matter integrity can also be detected in SLE patients without neuropsychiatric symptoms (non-NPSLE patients).
|
|
| 7. |
- Shastri, Ravi K., et al.
(författare)
-
MR Diffusion Tractography to Identify and Characterize Microstructural White Matter Tract Changes in Systemic Lupus Erythematosus Patients
- 2016
-
Ingår i: Academic Radiology. - : Elsevier BV. - 1076-6332. ; 23:11, s. 1431-1440
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose Systemic lupus erythematosus (SLE) is a predominantly female autoimmune disease that can affect the central nervous system. Neuropsychiatric symptoms are found in 25–70% of SLE patients. Using diffusion tensor imaging, various studies have reported changes in white matter integrity in SLE patients with neuropsychiatric symptoms (NPSLE patients). The purpose of this study was to investigate if changes can be detected in the individual white matter tracts in SLE patients regardless if neuropsychiatric symptoms are present or not. Materials and Methods Magnetic resonance diffusion tractography in several individual white matter tracts that are involved in language and memory tasks, including tracts to cortical association areas, was applied in 21 patients with NPSLE (mean age: 40.7 ± 12.8 years; range: 22–67 years), 18 patients with non-neurologic systemic lupus erythematosus (non-NPSLE) (mean age: 40.6 ± 12 years; range: 22–67 years), and 20 healthy control (HC) individuals (mean age: 40.64 ± 12.7 years; range: 19–60 years). Additional patients were evaluated; however, because of the inability to complete the scans required, they were excluded from the study. The fractional anisotropy of individual fiber tracts was measured and correlated with cognitive function and lupus disease severity index (Systemic Lupus Erythematosus Disease Activity Index [SLEDAI]) to assess predictability and diagnostic value of these measures for NPSLE. Results Analyses of variance of the tractography data from the analysis of 21 tracts revealed decreased fractional anisotropy in uncinate fasciculus in the NPSLE patients when compared to non-NPSLE lupus patients and HC individuals (P = 0.002). Non-NPSLE patients also demonstrated decreased fractional anisotropy when compared to healthy patients (P = 0.03). Decreased fractional anisotropy was also identified in the corpus callosum and corona radiata in NPSLE patients when compared to HC individuals; however, these tracts did not show a significant difference between NPSLE and non-NPSLE patients. Decreased fractional anisotropy in the uncinate fasciculus correlated with low SLEDAI score (R2 = 0.32). Conclusions Diffusion tensor tractography corroborates findings of decreased white matter integrity within the anterior corona radiate as well as the corpus callosum as previously described. Specifically, our study identified changes in the uncinate fasciculus in NPSLE and non-NPSLE patients that correlate with clinical changes (SLEDAI scores) and are independent of conventional T2 lesion burden.
|
|
| 8. |
- Wang, Page I., et al.
(författare)
-
Perfusion-weighted MR Imaging in Cerebral Lupus Erythematosus
- 2012
-
Ingår i: Academic Radiology. - : Elsevier BV. - 1878-4046 .- 1076-6332. ; 19:8, s. 965-970
-
Tidskriftsartikel (refereegranskat)abstract
- Rationale and Objective: Neuropsychiatric systemic lupus erythematosus (NPSLE) is a diagnostically challenging, severe, and life-threatening condition, which is currently lacking a "gold standard." Our aim with this study is to look for magnetic resonance (MR) perfusion differences in NPSLE, SLE, and healthy control (HC) patients and correlate our findings with clinical parameters. Materials and Methods: Twenty-four NPSLE patients, 21 SLE patients, and 21 HC underwent dynamic susceptibility contrast enhanced MR perfusion using a 3-T scanner. Nine prospectively selected intracranial regions of interest were placed in white and gray matter and the cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MU) values were calculated. Subjects underwent clinical evaluation with SLEDAI and serum antibodies. Results: The SLE patients had higher CBF and CBV compared to the HC overall (P =.01) and in specific areas (P =.03-.048). SLE patients with signs of active disease (elevated SLEDAI and anti-double-stranded DNA) had significantly elevated CBV, CBF, and MU in the posterior cingulate gyrus (P =.01-.02). No significant difference was seen in the magnetic resonance perfusion measurements of NPSLE patients compared to SLE and HC, although the NPSLE patients also showed higher CBV variability compared to the SLE (P =.0004) and HC cohort (P <.0001). Conclusion: SLE patients have increased CBV and CBF compared to healthy controls. The SLE patients with clinical markers for active disease have elevated CBV, CBF, and MU in the posterior cingulate gyrus. NPSLE patients show increased variability in perfusion measurements, which may explain why susceptibility contrast enhanced MRI has not yet provided a specific target for NPSLE.
|
|
