Continuous Theta-Burst Stimulation of the Contralesional Primary Motor Cortex for Promotion of Upper Limb Recovery After Stroke: A Randomized Controlled Trial

BACKGROUND

Despite improvements in acute stroke therapies and rehabilitation strategies, many stroke patients are left with long-term upper limb motor impairment. We assessed whether an inhibitory repetitive transcranial magnetic stimulation treatment paradigm started within 3 weeks after stroke onset promotes upper limb motor recovery.

METHODS

We performed a single-center randomized, sham-controlled clinical trial. Patients with ischemic stroke or intracerebral hemorrhage and unilateral upper limb motor impairment were randomized to 10 daily sessions of active or sham continuous theta-burst stimulation (cTBS) of the contralesional primary motor cortex combined with standard upper limb therapy, started within 3 weeks after stroke onset. The primary outcome was the change in the Action Research Arm Test score from baseline (pretreatment) at 3 months after stroke. Secondary outcomes included the score on the modified Rankin Scale at 3 months and the length of stay at the rehabilitation center. Statistical analyses were performed using mixed models for repeated measures.

RESULTS

We enrolled 60 patients between April 2017 and February 2021, of whom 29 were randomized to active cTBS and 31 to sham cTBS. One patient randomized to active cTBS withdrew consent before the intervention and was excluded from the analyses. The mean difference in the change in Action Research Arm Test score from baseline at 3 months poststroke was 9.6 points ([95% CI, 1.2-17.9]; P=0.0244) in favor of active cTBS. Active cTBS was associated with better scores on the modified Rankin Scale at 3 months (OR, 0.2 [95% CI, 0.1-0.8]; P=0.0225) and with an 18 days shorter length of stay at the rehabilitation center than sham cTBS ([95% CI, 0.0-36.4]; P=0.0494). There were no serious adverse events.

CONCLUSIONS

Ten daily sessions of cTBS of the contralesional primary motor cortex combined with upper limb training, started within 3 weeks after stroke onset, promote recovery of the upper limb, reduce disability and dependence and leads to earlier discharge from the rehabilitation center.

REGISTRATION

URL: https://trialsearch.who.int/; Unique identifier: NTR6133.

P05.04.A Disconcordance between different molecular methods to assess homozygous deletion of theCDKN2A/B locus in IDH-mutant astrocytomas

Background

The fifth edition of the WHO Classification of Tumors of the Central Nervous System (WHO CNS 5), includes molecular parameters for both diagnosis and grading in addition to histological features. For IDH-mutant astrocytoma, homozygous deletion (HD) of CDKN2A/B now results in WHO grade 4, even in the absence of microvascular proliferation or necrosis. CDKN2A/B deletions can be determined by various techniques including shallow and targeted sequencing, and using genome wide DNA-methylation arrays. Various algorithms to call deletions also exist for each platform. Concordance between the various techniques and algorithms is however unknown. Because of the importance to properly call CDKN2A/B deletions, we compared two techniques to call HD in IDH-mutant astrocytoma patients.

Methods

Samples from 110 IDH-mutant astrocytoma patients enrolled in the GLASS-NL study, and therefore samples from at least two surgical resections per patient, were available. Overall survival (OS) was measured from date of first surgery.

Both DNA-methylation data and shallow whole-genome sequencing (sWGS) was collected from 219 samples from 101 patients. For DNA-methylation analysis, HD of CDKN2A/B was defined by <-0.6 log2 intensity combined with visual assessment on samples with log2 intensity between -0.6 and -0.2 (method 1), or by using a hard cutoff of <-0.415 log2 intensity, as determined by Shirahata et al. (method 2). Absolute copy number profiles were estimated by ACE from sWGS data, HD of CDKN2A/B was defined by a loss of at least 1.2 CDKN2A alleles (method 3). Agreement score and Cohen’s kappa (κ) as an index for interrater agreement was calculated.

Results

Method 1 and method 2 called an HD of CDKN2A/B in 39 and 33 cases, respectively; method 1 called an HD of CDKN2A/B in 9 cases in which method 2 did not detect an alteration. The agreement was strong with 95% agreement and κ = 0.842.

Method 3 called an HD of CDKN2A/B in 45 cases of which 12 and 19 were not detected by method 1 and method 2 respectively. Method 3 showed an almost perfect level of agreement with method 1, with 97% agreement and κ = 0.911, and a moderate agreement with method 2, with 89% agreement and κ = 0.671.

Survival analysis showed that there was no significant difference in survival when patients were stratified by CDKN2A/B status of the initial sample of all methods. However, when stratified by CDKN2A/B status of the first recurrence, all methods showed a stronger association with OS (method 1: p = 0.001, HR = 2.61[1.44-4.72]; method 2: p = 0.0024, HR = 2.34[1.33-4.11]; method 3: p = 0.0099, HR = 2.34[1.2-4.55]).

Conclusion

Different methods and different cutoffs to determine the presence of a HD in CDKN2A/B may result in different test outcomes. Quality of the DNA, tumor cell percentage of the sample and ploidy are likely to influence the call of homozygous CDKN2A/B deletion. Ring tests are recommended to improve reliability.

OS08.1.A Integrative molecular analysis of matched primary and recurrent IDH-mutant astrocytoma; an update from the GLASS-NL consortium

Background

The evolutionary processes that drive tumor progression in patients with IDH-mutant astrocytoma remain largely unclear. The GLASS-NL consortium was initiated to gain insight into the molecular mechanisms underlying glioma evolution and to identify markers of progression in IDH-mutant astrocytomas. Ultimately, such markers can assist clinical decision making. Here, we present the DNA methylation profiling, RNA-sequencing and shallow whole-genome sequencing (sWGS) of samples included in the GLASS-NL study.

Methods

Eligible were patients with an IDH-mutant, 1p19q non-codeleted, astrocytoma at first diagnosis who underwent surgical resection of the tumor at least twice separated by >6 months, and of whom paired tumor samples were available for analyses. Overall survival (OS) was measured from date of initial surgery.

DNA methylation profiling was performed with the 850kEPIC array, and transcriptome and sWGS by NGS. After quality control, DNA methylation data of 103, expression data of 91, and sWGS data of 92 patients was available for further analysis. Methylation classes were determined according to Capper et al. and copy number alterations (CNAs) were extracted from both sWGS and DNA-methylation data.

Results

110 patients were identified from various medical centers in the Netherlands. The median time between surgical resections was 41.9 months (IQR:26.5-65.9) and after initial surgery, 63% and 22% of the patients were treated with radiotherapy or chemotherapy respectively. The proportion of samples assigned to the high grade methylation class increased ~three-fold at recurrence. 83% of patients that progressed from low to high grade, received treatment prior to recurrent surgery, as compared to 53% of the patients that remained low grade.

Genome wide DNA methylation levels of recurrent samples were lower than that of initial samples. This difference is explained by the increased number of high grades at recurrence, since near identical DNA methylation levels were observed in samples that remained low grade.

Analysis of CNAs revealed chromosomal arms that were more frequently altered in high grade samples. Univariate analysis showed that losses in 3p, 9p, 10q, 13q and 14q were associated with poor OS.

More than 800 differentially expressed genes between initial and recurrent tumor samples were found. Chromosomal enrichment analysis revealed a locus on chromosome 6 enriched with histone genes, to be significantly up-regulated over time.

Conclusion

Longitudinal methylation profiling of IDH-mutant astrocytoma reveals a shift towards a higher grade at tumor recurrence coinciding with reduced DNA methylation levels, and increased frequency of CNAs. Longitudinal expression analysis showed changes in expression of >800 genes, including an up-regulated locus enriched with histone genes. Further integrative analyses are ongoing and will be reported at the meeting.

OS09.7.A Experiences and unmet needs of grade 2-4 glioma patients and (health care) professionals regarding (return to) work: the BrainWork study

Background

In the Netherlands, 1,200 persons are annually diagnosed with a glioma, of whom many are of working age. Studies regarding cancer and work often exclude primary brain tumour patients, due to specific problems these patients may experience. Hence, the aim was to explore the experiences and unmet needs regarding return to work, work retention, or work discontinuation of both grade 2-4 glioma patients, and involved (health care) professionals.

Material and Methods

Individual semi-structured interviews were held with grade 2-4 glioma patients as well as health care and occupational professionals involved in (the care for) glioma patients. Grade 2-4 glioma patients were eligible to participate if they were of working age and had an employment contract at time of diagnosis. Recruitment of patients was performed via three hospitals and via social media. The professionals were recruited via the network of researchers linked to BrainWork. Interviews were transcribed verbatim, and thematically analysed using ATLAS.ti9.

Results

Nineteen glioma patients participated in this study (68% male, mean age 45 (SD 11), 58% grade 2, 16% grade 3, 26% grade 4). The main themes identified were: 1) impact of glioma-specific consequences on work ability, 2) communicating about an invisible, progressive illness at work: discrepancies in perceptions, 3) working with a brain tumour: looking at possibilities, and 4) navigating offers of (work-related) support. Sixteen professionals were interviewed (e.g., clinical neuro-oncologist, insurance physician) with an average experience of fifteen years. Four key themes were identified: (1) distilling the right approach: generic or specific vocational rehabilitation?; (2) work adjustments are common, but information deficiency causes delay; (3) opinions about work ability are diverse and influenced by glioma-specific characteristics; and (4) need for attention and tailored recommendations regarding glioma and work.

Conclusions

Working is possible for glioma patients although they encounter glioma-specific problems, and commonly need work adjustments. These adjustments should be communicated early, to prevent employer-employee conflicts. A specific reintegration plan, including a neuropsychological assessment and a glioma-tailored rehabilitation program, is considered the most adequate approach. Open communication between the patient and the (work) environment in general is necessary to abate discrepancies in perception. Communication between health care professionals and occupational professionals should be improved to diminish differences in opinions about the work ability of glioma patients. Finally, more attention and more tailored recommendations regarding glioma and work are necessary.

Gate-controlled quantum dots and superconductivity in planar germanium

Superconductors and semiconductors are crucial platforms in the field of quantum computing. They can be combined to hybrids, bringing together physical properties that enable the discovery of new emergent phenomena and provide novel strategies for quantum control. The involved semiconductor materials, however, suffer from disorder, hyperfine interactions or lack of planar technology. Here we realise an approach that overcomes these issues altogether and integrate gate-defined quantum dots and superconductivity into germanium heterostructures. In our system, heavy holes with mobilities exceeding 500,000 cm2 (Vs)-1 are confined in shallow quantum wells that are directly contacted by annealed aluminium leads. We observe proximity-induced superconductivity in the quantum well and demonstrate electric gate-control of the supercurrent. Germanium therefore has great promise for fast and coherent quantum hardware and, being compatible with standard manufacturing, could become a leading material for quantum information processing.

Prism Adaptation in Rehabilitation? No Additional Effects of Prism Adaptation on Neglect Recovery in the Subacute Phase Poststroke: A Randomized Controlled Trial

Background. Patients with neglect ignore or respond slower to contralesional stimuli. Neglect negatively influences independence in activities of daily living (ADL). Prism adaptation (PA) is one of the most frequently studied treatments, yet there is little evidence regarding positive effects on neglect behavior in ADL. Objective. To assess whether PA in the subacute phase ameliorates neglect in situations of varying complexity. Methods. A total of 70 neglect patients admitted for inpatient stroke rehabilitation received either PA or sham adaptation (SA) for 2 weeks, with full access to standard treatment. There were 7 time-dependent measurements (baseline and 1-4, 6, and 14 weeks after start of treatment). The primary outcome was change of neglect as observed during basic ADL with the Catherine Bergego Scale (CBS). Secondary outcomes were changes in performance on a dynamic multitask (ie, the Mobility Assessment Course [MAC]) and a static paper-and-pencil task (ie, a shape cancellation task [SC]). Results. In all, 34 patients received PA and 35 SA. There were significant time-dependent improvements in performance as measured with the CBS, MAC, and SC (all F > 15.57; P < .001). There was no significant difference in magnitude of improvement between groups on the CBS, MAC, and SC (all F < 2.54; P > .113]. Conclusions. No beneficial effects of PA over SA in the subacute phase poststroke were observed, which was comparable for situations of varying complexity. Heterogeneity of the syndrome, time post–stroke onset, and the content of treatment as usual are discussed. Basic knowledge on subtypes and recovery patterns would aid the development of tailored treatment.

Predictors of physical independence at discharge after stroke rehabilitation in a Dutch population

The aim of this study was to identify predictors, available at admission, of physical independence at discharge from inpatient rehabilitation. Secondary aims were to identify predictors of functional gain and length of stay (LOS). We included 1310 adult stroke patients who were admitted for inpatient rehabilitation in five Dutch rehabilitation centres. Data on the Utrecht Scale for Evaluation of Clinical Rehabilitation at admission and discharge (physical and cognitive independence, mood, pain and fatigue), age, sex and in a subsample stroke characteristics as well were collected. A prediction model was created using random coefficient analysis. None of the stroke characteristics were independently associated with physical independence or functional gain at discharge, or LOS. Higher physical and cognitive independence scores and severe pain at admission were predictors of higher physical independence scores at discharge. Furthermore, lower physical independence scores, higher cognitive independence scores, less pain at admission and younger age predicted more functional gain. Finally, lower physical and cognitive independence scores at admission and younger age predicted longer LOS. Physical independence at admission was the most robust predictor for rehabilitation outcome in a Dutch rehabilitation setting. To a lesser extent, age, cognitive independence and pain predicted rehabilitation outcome after stroke. Treatment of cognition and pain should be taken into account during rehabilitation. Further work needs to be carried out to establish whether focusing on these factors improves outcome after rehabilitation.

Exploring near and far regions of space: distance-specific visuospatial neglect after stroke

Visuospatial neglect has been observed in the horizontal (left/right) and vertical (up/down) dimension and depends on the distance at which a task is presented (near/far). Previously, studies have mainly focused on investigating the overall severity of neglect in near and far space in a group of neglect patients instead of examining subgroups of neglect patients with different types of distance-specific neglect. We investigated the spatial specificity (near vs. far space), frequency, and severity of neglect in the horizontal and vertical dimensions in a large group of stroke patients. We used three tasks to assess neglect in near (30 cm) and far (120 cm) space: a shape cancellation, letter cancellation, and a line bisection task. Patients were divided into four groups based on their performance: a group without neglect (N-F-), a near only neglect (N+F-), a far only neglect (N-F+), and a near and far neglect group (N+F+). About 40% of our sample showed neglect. Depending on the task, N+F- was observed in 8 to 22% of the sample, whereas N-F+ varied between 8% and 11%, and N+F+ varied between 11% to 14% of the sample. The current findings indicate that horizontal and vertical biases in performance can be confined to one region of space and are task dependent. We recommend testing for far space neglect during neuropsychological assessments in clinical practice, because this cannot be diagnosed using standard paper-and-pencil tasks.

The feasibility of computer-based prism adaptation to ameliorate neglect in sub-acute stroke patients admitted to a rehabilitation center

Introduction: There is wide interest in transferring paper-and-pencil tests to a computer-based setting, resulting in more precise recording of performance. Here, we investigated the feasibility of computer-based testing and computer-based prism adaptation (PA) to ameliorate neglect in sub-acute stroke patients admitted to a rehabilitation center.

Methods: Thirty-three neglect patients were included. PA was performed with a pair of goggles with wide-field point-to-point prismatic lenses inducing an ipsilesional optical shift of 10°. A variety of digitalized neuropsychological tests were performed using an interactive tablet immediately before and after PA.

Results: All 33 patients [mean age 60.36 (SD 13.30)], [mean days post-stroke 63.73 (SD 37.74)] were able to work with the tablet and to understand, perform, and complete the digitalized tests within the proposed time-frame, indicating that there is feasibility of computer-based assessment in this stage post-stroke. Analyses of the efficacy of PA indicated no significant change on any of the outcome measures, except time.

Discussion: In conclusion, there is feasibility of computer-based testing in such an early stage, which makes the computer-based setting a promising technique for evaluating more ecologically valid tasks. Secondly, the computer-based PA can be considered as a reliable procedure. We can conclude from our analysis, addressing the efficacy of PA, that the effectiveness of single session PA may not be sufficient to produce short-term effects on our static tasks. Further studies, however, need to be done to evaluate the computer-based efficacy with more ecologically valid assessments in an intensive double-blind, sham-controlled multiple PA treatment design.

Feasibility of high-dose dobutamine stress SSFP Cine MRI at 3 Tesla with patient adaptive local RF Shimming using dual-source RF transmission: initial results

PURPOSE

To investigate the feasibility of high-dose dobutamine stress (HDDS) imaging using SSFP sequences at 3 T employing patient-adaptive local RF-shimming using a dual-source RF transmission system.

MATERIALS AND METHODS

13 Patients underwent a HDDS protocol on a 3 T MRI scanner (Achieva 3.0T-TX, Philips Healthcare), equipped with a dual-source RF transmission system. SSFP cine sequences using patient-adaptive local RF-shimming (RF-S) were compared to cine images acquired without additional shimming. Image quality was evaluated on a 4-point grading scale and number of non-diagnostic segments assessed. Contrast (CN) between myocardium (SIM) and blood pool (SIB) was calculated [(SIB-SIM)/(SIB+SIM)].

RESULTS

Image quality both at rest and maximum stress was significantly improved with RF-S (ED:3.56±0.5 vs. 3.23±0.63; ES:3.4±0.5 vs. 3.1±0.7) compared to no RF-S (ED:2.9±0.72 vs. 2.15±0.78; ES:2.64±0.74 vs. 1.95±0.76; p<0.01). The amount of non-diagnostic segments was significantly reduced when using RF-S at rest and stress (3 vs. 39; 19 vs. 78, p<0.05). All HDDS studies were diagnostic if performed with RF-S (n=13/13) in comparison to conventional shimming (n=5/13). Image contrast was improved for SSFP sequences with RF-S (0.53±0.08) compared to conventional images (0.46±0.09, p=0.06).

CONCLUSION

Patient-adaptive local RF-shimming using a dual-source RF transmission system allows for reliable SSFP imaging in a clinical high-dose dobutamine stress protocol at 3 T. RF-S significantly improves image quality and reduces the number of non-diagnostic myocardial segments.

Influence of gravity compensation on kinematics and muscle activation patterns during reach and retrieval in subjects with cervical spinal cord injury: an explorative study

Many interventions in upper-limb rehabilitation after cervical spinal cord injury (CSCI) use arm support (gravity compensation); however, its specific effects on kinematics and muscle activation characteristics in subjects with a CSCI are largely unknown. We conducted a cross-sectional explorative study to study these effects. Nine subjects with a CSCI performed two goal-directed arm movements (maximal reach, reach and retrieval) with and without gravity compensation. Angles at elbow and shoulder joints and muscle activation were measured and compared. Seven subjects reduced elbow extension (range 1.8°-4.5°) during the maximal reaching task with gravity compensation. In the reach and retrieval task with gravity compensation, all subjects decreased elbow extension (range 0.1°-11.0°). Eight subjects executed movement closer to the body. Regarding muscle activation, gravity compensation did not influence timing; however, the amplitude of activation decreased, especially in antigravity muscles, namely mean change +/- standard deviation of descending part of trapezius (18.2% +/- 37.5%), anterior part of deltoid (37.7% +/- 16.7%), posterior part of deltoid (32.0% +/- 13.9%), and long head biceps (49.6% +/- 20.0%). Clinical implications for the use of gravity compensation in rehabilitation (during activities of daily living or exercise therapy) should be further investigated with a larger population.

Randomized phase II trial of erlotinib (E) versus temozolomide (TMZ) or BCNU in recurrent glioblastoma multiforme (GBM): EORTC 26034

2005

Background: In 40–50% of GBM epidermal growth factor receptor (EGFR) is amplified, and often constitutively activated (EGFRvIII mutant). EGFR is therefore a potential therapeutic target. Previous studies suggested activity of EGFR tyrosine-kinase inhibitors in recurrent GBM, particularly in specific molecular subsets. This study explored erlotinib (E) activity in recurrent GBM. Methods: Randomized phase II trial. Eligibility criteria: histologically proven GBM, recurrent >3 months after radiotherapy, Karnofsky performance status (KPS) =70, no prior chemotherapy for recurrent disease, tissue sample for EGFR studies. Patients (pts) received E 150mg/day (300mg/day if on enzyme inducing anti-epileptic drugs [EIAEDs]), or control (TMZ 150–200mg/m2, day 1–5 q4wk or BCNU 60–80mg/m2 i.v., day 1–3 q8wk). If no significant toxicity, E was escalated to 200mg (500mg in patients on EIAEDs). The primary endpoint was 6 months’ PFS in =10/50 pts on E (20%); P0 was set at 15%, and P1 at 30%. Response was assessed with Macdonald’s criteria. EGFR amplification (FISH) and expression of EGFR, EGFRvIII and PTEN (immunohistochemistry [IHC]) were assessed. Results: 110 patients were randomized (54 E, 56 control: 27 TMZ; 29 BCNU). Median age 55 years; median KPS 90. All but 1 patient started treatment; median number of cycles was 2 for E, 4 for TMZ and 1 for BCNU. Grade 3/4 toxicities likely related to E: dermatological (5); hemorrhage (1). Grade 3/4 toxicities for control were mainly hematological (3 TMZ, 13 BCNU). Three pts discontinued E due to toxicity. Six-month PFS was 12% for E, 24% for control. Six and 12-month survival were 61% and 24% for E, and 63% and 26% for control. Two responses were seen on control; the best response on E was SD (n=6). Patients with EGFRvIII mutations (13 in E arm, 8 in control arm) had shorter PFS (p=0.007) and OS (p=0.004) regardless of treatment. Response to E was not correlated with EGFR expression, EGFR amplification or EGFRvIII mutation. Conclusions: This randomized, controlled phase II study did not find sufficient activity for erlotinib in the general population of recurrent GBM. The presence of EGFRvIII mutations was not predictive for response.

No significant financial relationships to disclose.

Dendritic cells in the cerebrospinal fluid and peripheral nerves in Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy

The role of antigen-presenting cells (APC) involved in induction of T and B cell mediated autoaggressive immunity in Guillain-Barre syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is poorly understood. We studied the numbers and phenotype of dendritic cells (DC) in blood and cerebrospinal fluid (CSF) over the course of GBS and CIDP before and after immunomodulatory treatment. Four out of seven GBS patients examined prior to treatment with high-dose intravenous immunoglobulins (IvIg) had elevated numbers of CD123(+) plasmacytoid DC in the CSF, while both GBS and CIDP patients examined prior to treatment had elevated numbers of CD11c(+) myeloid DC in the CSF, as compared to patients with noninflammatory neurological diseases (OND). The percentages of blood DC expressing the cell surface marker CD1a, co-stimulatory molecules CD80 and CD86, adhesion molecule CD54, and chemokine receptors CCR1, CCR2, CCR5, and CXCR4 were not affected in GBS or CIDP. The immunohistochemistry of sural nerve biopsies revealed CD11c(+)CD83(-)CD14(-)CD16(-) immature myeloid DC at low numbers, mostly in the perineurium, without difference between CIDP patients and controls. In contrast, the numbers of CD11c(+)CD14(+)/CD16(+) macrophages were higher within the endoneurium in CIDP patients compared with the controls. The recruitment of DC to CSF in GBS and CIDP may be important in capturing antigens released from inflamed spinal nerve roots into CSF and in transferring these antigens from CSF to local lymph nodes, where naive T and B cells may be activated.

Multiple sclerosis: a study of chemokine receptors and regulatory T cells in relation to MRI variables

Magnetic resonance imaging (MRI) remains the most valuable tool for monitoring disease activity and progression in patients with multiple sclerosis (MS), a chronic demyelinating disease of the central nervous system (CNS) with presumably autoimmune etiology. Chemokine receptors have been implicated in MS as key molecules directing inflammatory cells into the CNS. Regulatory (CD4+CD25+) T cells (Tr cells) are important in suppressing autoimmunity, and their absolute or functional deficit could be expected in MS. In the present study, venous blood was obtained from MS patients concurrent with MRI examination of the brain, and expression of chemokine receptors CCR1, CCR2, CCR5, CXCR3 and CXCR4 by CD4 T cells and monocytes, proportions of Tr cells, as well as expression of CD45RO, CD95, CTLA-4, HLA-DR and interleukin (IL)-10 by Tr cells and non-Tr (CD25-) CD4 T cells was analyzed by flow cytometry. Surface expression of CXCR3 by CD4 T cells was downregulated in the group of patients with high lesion load (LL) on T2-weighted images and gadolinium (Gd)-enhancing lesions on T1-weighted images, compared to the group with high LL and no Gd-enhancing lesions, and to the group with low LL, suggesting internalization of CXCR3 due to the release of its chemokine ligand (IP-10/CXCL10) from active MS lesions. Proportions of Tr cells amongst all CD4 T cells, and expression of IL-10 by Tr cells were increased in the patients with high LL and Gd-enhancing lesions. These results suggest that there is correlation between MRI parameters, chemokine receptor expression and the status of circulating Tr cells in MS, but further studies need to discriminate between pathogenetically relevant and bystander phenomena.

Cytokines in multiple sclerosis: methodological aspects and pathogenic implications

Multiple sclerosis (MS) is one of the leading causes of disability among young adults of Caucasian origin. One hundred and fifty years after the first description of the disease, the cause of MS remains unknown. Ironically, the few hypotheses concerning MS pathogenesis that are valid today were first proposed over a hundred years ago. However, equipped with the advanced technology of molecular biology and imaging systems, we are at present progressively uncovering dues to understanding the pathogenesis of the disease. It is dearly evident that aberrant immune responses occur in MS, and it is likely that the spectrum of cytokines produced decisively influences disease outcome. The detrimental consequences of IFN-gamma and the beneficial effects of IFN-beta treatment in MS support this hypothesis. However, there are still major gaps in our knowledge of the involvement of cytokines in MS. Numerous studies have addressed the question of cytokine levels in MS, often with conflicting results; elevated, normal and decreased levels of almost all cytokines have been reported. This scenario most probably reflects methodological dilemmas as well as the complex biology of cytokines. Here we focus on possible reasons for the discrepancies of results reported on cytokines in MS and summarize findings obtained in particular by the application of enzyme-linked immunospot (ELISPOT) assays to cytokine studies in MS.

Elevated expression of CCR5 by myeloid (CD11c+) blood dendritic cells in multiple sclerosis and acute optic neuritis

Myeloid and plasmacytoid dendritic cells (DC) are present in cerebrospinal fluid (CSF) in non-inflammatory neurological diseases (NIND) and elevated in clinically definite multiple sclerosis (MS) and in early MS - acute monosymptomatic optic neuritis (ON). Here, we show that expression of CCR5, a chemokine receptor for regulated on activation, normal T cell expressed and secreted (RANTES) and macrophage inflammatory protein (MIP)-1alpha/beta, is elevated on blood myeloid (CD11c+) DC in MS and ON compared to non-inflammatory controls. In contrast, expression of CXCR4, a receptor for stromal cell-derived factor (SDF)-1alpha, is similar in all groups. Blood myeloid DC from MS patients respond chemotactically to RANTES and MIP-1beta, which are expessed in MS lesions. In active MS and ON, expression of CCR5 by myeloid DC in blood correlates with numbers of these cells in CSF. Thus, elevation of CCR5 may contribute to recruitment of myeloid DC to CSF in MS and ON. Recruitment of plasmacytoid DC to CSF appears to be CCR5-independent.

Non-T(H)1 cytokines are augmented systematically early in Guillain-Barré syndrome

The T(H)1 vs non-T(H)1 cytokine balance in Guillain-Barré syndrome (GBS) is unknown. Using enzyme-linked immunospot (ELISPOT) assays, we observed elevated numbers of interleukin (IL)-6 and IL-10-secreting blood mononuclear cells (BMNC) during the acute phase in untreated patients, and low levels of tumor necrosis factor alpha-secreting BMNC in the recovery phase of GBS. Numbers of IL-12p70-secreting BMNC were not affected over the course of GBS. The non-T(H)1 cytokine profile observed early in GBS may explain the self-limited clinical course associated with GBS.

Enzyme-linked immunospot assays provide a sensitive tool for detection of cytokine secretion by monocytes

Blood monocytes as well as tissue-differentiated macrophages play a pivotal role in controlling immune reactions. Monocytes regulate the extent, nature, and duration of immune responses by secretion of cytokines. Interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), IL-10, and IL-12 are of particular interest, since IL-12 shifts the immune response towards a Th1 type, facilitating the production of, e.g., TNF-alpha and IL-6, while IL-10 counteracts Th1 responses and promotes the production of Th2-related cytokines such as IL-4. A tight regulation of these four cytokines keeps the balance and decides whether Th1 or Th2 will predominate in immune reactions. Enzyme-linked immunospot (ELISPOT) assays are among the most-sensitive and -specific methods available for cytokine research. They permit ex vivo identification of individual cells actively secreting cytokines. In the present study we prepared monocytes from healthy subjects' blood and adapted ELISPOT assays to define optimal conditions to detect and enumerate monocytes secreting IL-6, TNF-alpha, IL-10, and IL-12. The optimal time for monocyte incubation was 24 h, and optimal monocyte numbers (in cells per well) were 2,000 for IL-6, 1,000 for TNF-alpha, 50,000 for IL-10, and 100,000 for enumeration of IL-12 secreting monocytes. Among healthy subjects, 10% +/- 5% of the monocytes secreted IL-6, 12% +/- 12% secreted TNF-alpha, 0.1% +/- 0.1% secreted IL-10, and 0.2% +/- 0.3% secreted IL-12 (values are means +/- standard deviations). In conclusion, ELISPOT assays constitute a valuable tool to enumerate monocytes secreting IL-6, TNF-alpha, IL-10, and IL-12 and probably to enumerate monocytes secreting other cytokines and proteins.

Functional cardiac MR imaging with steady-state free precession (SSFP) significantly improves endocardial border delineation without contrast agents

Contrast between blood and myocardium in standard turbo gradient echo MR techniques (TFE) used routinely in clinical practice is mainly caused by unsaturated inflowing blood. Steady-state free precession (SSFP) has excellent contrast even in the absence of inflow effects. In 45 subjects cardiac cine loops in two long axis projections were acquired using TFE and compared with SSFP. A visual score (range 0 worst - 3 best) was assigned for endocardial border delineation for six myocardial segments in two long axis views. Endocardial border delineation score for TFE was 1.3 +/- 0.3 per segment and 2.4 +/- 0.3 for SSFP (P < 0.0001). Signal intensity blood/signal intensity myocardium was 1.5 +/- 0.4 at enddiastole and 1.4 +/- 0.3 at systole for TFE and 3.5 +/- 1.1 and 3.2 +/- 1.3 for SSFP, respectively (P < 0.0001). SSFP increases contrast between blood and myocardium more than twofold, resulting in an improved endocardial border definition. This may reduce variability for the determination of cardiac volumes and ejection fraction.

Systemic immune response in whiplash injury and ankle sprain: elevated IL-6 and IL-10

Whiplash injury and whiplash-associated disorders (WAD) are significant problems of modern society. Numerous attempts have been made to characterize the nature of whiplash injury. Whether the immune system is involved during the disease process is not known. In a prospective study, using enzyme-linked immunospot (ELISPOT) assays, we examined numbers of blood mononuclear cells (MNC) secreting pro- (IFN-gamma, TNF-alpha, IL-6) and anti-inflammatory (IL-10) cytokines in patients with WAD and, for reference, patients with ankle sprain and multiple sclerosis and healthy subjects. An immune response reflected by elevated numbers of TNF-alpha- and IL-10-secreting blood MNC was observed in patients with WAD examined within 3 days compared to 14 days after the whiplash injury. The patients with WAD examined within 3 days after the injury had also higher numbers of IL-6 and IL-10 secreting blood MNC compared to healthy subjects. The alterations of cytokine profiles observed in WAD were also observed in patients with ankle sprain when examined within 3 days after trauma. In contrast, there were no differences for cytokine profiles between patients with WAD examined 14 days after the whiplash injury and healthy subjects. Relatively minor trauma like WAD and ankle sprain are associated with a systemic dysregulation in numbers of cells secreting pro- as well as anti-inflammatory cytokines.

Matrix metalloproteinase and cytokine profiles in monocytes over the course of stroke

Stroke is a common cause of death and disability in our society. Stroke is associated with changes in immune responses within the central nervous system as well as systemically. The cells contributing to such changes as well as the factors contributing to formation of the inflammatory infiltrate observed in stroke remain to be clarified. In this study, blood monocytes and corresponding mononuclear cells (MNC) were separated and examined in parallel within 4 days and 1-3 months after onset of ischemic stroke. Numbers of TNF-alpha-, IL-12-, IL-6-, and IL-10-secreting cells and of cells expressing mRNA for matrix metalloproteinase (MMP)-1, -2, -7, -9 and tissue inhibitor of MMP (TIMP)-1 were studied. The TNF-alpha-, IL-12-, and IL-6-secreting monocytes and MNC were elevated during the acute phase compared to healthy controls. Such differences were not observed when stroke patients were examined during convalescence. The IL-10-secreting monocytes did not change over the course of stroke. Levels of monocytes expressing MMP-1, MMP-7 and TIMP-1 mRNA were elevated in the acute phase of stroke patients compared to convalescence and healthy controls, as were levels of MMP-1, -2, -7, -9 and TIMP-1 mRNA expressing blood MNC. The MMP-2 and -9 activity as measured by zymography also was higher in MNC supernatants in the acute phase of stroke compared to convalescence. The high levels of proinflammatory cytokines and MMPs in blood monocytes and MNC further demonstrate the presence of systemic aberrations in the acute phase of stroke. Such changes may contribute to the influx of blood-borne cells into the ischemic lesions during the acute phase of stroke.

Chemokines and their receptors in whiplash injury: elevated RANTES and CCR-5

The human sufferings and socioeconomic burden due to whip-lash-associated disorders (WAD) are obvious but the pathogenesis of WAD is obscure. The possible involvement of the immune system during the disease process in WAD is not known. Effector molecules including chemokines and their receptors could play a role in WAD. In a prospective study using flow cytometry, we examined percentages of blood mononuclear cells (MNC) expressing the chemokines RANTES, MCP-1, MIP-1alpha, MIP-1beta, and IL-8, the chemokine receptor CCR-5, the T cell activation marker CD25, and the T cell chemoattractant IL-16 in patients with WAD and, for reference, in healthy controls. Higher percentages of RANTES-expressing blood MNC and T cells were observed in patients with WAD examined within 3 days compared to 14 days after the whiplash injury and, likewise, compared with healthy controls. The patients with WAD examined within 3 days after the accident also had higher percentages of CCR-5-expressing blood MNC, T cells, and CD45RO+ T cells compared to healthy controls. In contrast, there were no differences for any of these variables between patients with WAD examined 14 days after injury and healthy controls. In conclusion, WAD is associated with a systemic but transient dysregulation in percentages of RANTES and CCR-5 expressing MNC and T cells.

Multiple sclerosis: elevated expression of matrix metalloproteinases in blood monocytes

Multiple sclerosis (MS) is an inflammatory, demyelinating disease of the central nervous system (CNS) characterized by blood-brain barrier (BBB) breakdown. Disruptions of BBB continuity result in an influx of activated T cells and monocytes, and could contribute to lesion formation in the CNS. Matrix metalloproteinases (MMP) are enzymes implicated in BBB disruption, and in degradation of extracellular matrix proteins and myelin components. An imbalance in levels of MMP and tissue inhibitors of MMP (TIMP) has been implicated in the pathogenesis of MS. Since monocytes form a major cell population in acute MS lesions and may facilitate their entrance into the CNS by secretion of MMP, knowledge on MMP expression by blood monocytes could be useful to improve our understanding of the pathogenesis of MS. In the present study, we examined the expression of MMP-1, -3, -7, -9, -14 and TIMP-1 mRNA by blood monocytes in patients with MS using in situ hybridization. Levels of MMP-1, -3, -7, -9 and of TIMP-1 mRNA expressing monocytes were elevated in MS compared to controls, while those of MMP-14 did not differ. We therefore conclude that MS is associated with elevated levels of MMP and TIMP expressing blood monocytes that may contribute to MS pathogenesis.

Dendritic cells derived from patients with multiple sclerosis show high CD1a and low CD86 expression

Dendritic cells (DC) are important antigen presenting cells (APC) and play a major role in initiating and orchestrating immune responses by priming T cells. Little is known about involvement of DC in multiple sclerosis (MS), where auto-aggressive T cells against myelin autoantigens are considered to contribute to inflammation and demyelination in the central nervous system. In this study, we compared phenotype and cytokine secretion of DC from patients with MS, other neurological diseases (OND) and healthy subjects. DC were generated from blood adherent mononuclear cells (MNC) by culture for 7 days with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). The yield and morphology of DC were similar in MS patients and controls. In both, the DC phenotype was that of immature myeloid lineage, comprising CD1a+ and CD11c+. The proportion of CD1a+ DC, being important for presentation of lipid antigens to T cells, was higher in MS patients compared to controls. The proportion of CD86+ DC, a co-stimulatory molecule that is assumed to promote Th2 differentiation, was low in MS. Low proportions of CD86+ DC were only observed in untreated MS patients but not in patients treated with IFN-beta. Production of IL-10 and IL-12 p40 by DC did not differ in MS patients and controls. These findings indicate that alterations of functionally important surface molecules on DC are associated with MS.

IL-12/IL-12R system in multiple sclerosis

IL-12/IL-12 receptor (IL-12R) system orchestrates the Th1 pathway of the immune system by maintaining one of the major bridges between innate and adaptive immune responses. Here, we studied both sides of this system in patients with multiple sclerosis (MS) and in controls. MS patients displayed elevated IL-12Rbeta1 and IL-12Rbeta2 expression on PHA-activated T cells compared to healthy subjects. Higher percentages of IL-12Rbeta1 and IL-12Rbeta2 positive T cells in cerebrospinal fluid (CSF) compared to blood were observed both in MS and other neurological diseases (OND). In contrast, numbers of IL-12 secreting blood mononuclear cells (MNC) were similar in MS and controls. The functional importance of high IL-12Rbeta2 in MS was underlined by the finding that IL-12 stimulated IFN-gamma production and proliferation of PHA-activated T cells correlated with levels of IL-12Rbeta2 expression. Our data indicates a dysregulation of the IL-12/IL-12R system in MS. It is suggested that even in the absence of increased IL-12 levels, the net effect of IL-12 might be augmented in MS by elevated expression of its receptor.

Renal artery blood flow: quantification with breath-hold or respiratory triggered phase-contrast MR imaging

The aim of this study was to evaluate the validity and reproducibility of breath-hold and respiratory triggered phase-contrast (PC) MR imaging techniques in the measurement of renal artery blood flow. In 12 healthy subjects cardiac-gated PC flow measurements were obtained in the renal arteries using a breath-hold and a respiratory-triggered technique. The flow measurements were repeated in each renal artery separately. Comparison between the sum of flow measurements in the renal arteries and the difference in aortic flow measurements above and below the renal arteries served as an internal control. The flow measurements showed a good reproducibility both with the breath-hold (r=0.92, p < 0.0001) and with the respiratory-triggered (r = 0.91, p < 0.0001) technique. The validity of both methods was good and there was no statistically significant difference. Reproducible quantitative measurements of renal artery blood flow are possible with respiratory controlled, cardiac-gated, PC MR imaging.

Monocytes in multiple sclerosis: phenotype and cytokine profile

Multiple sclerosis (MS) is an inflammatory demyelinating disease characterised by immune abnormalities in the central nervous system (CNS) as well as systemically. Activated, blood-borne monocytes are abundant in MS lesions, the properties of circulating monocytes are incompletely known. To delineate phenotype and levels of cytokine secreting monocytes in MS patients' blood, ELISPOT assays were used for detection and enumeration of monocytes secreting the cytokines IL-6, IL-12, TNF-alpha and IL-10. In parallel, the expression by monocytes of co-stimulatory molecules (CD40, CD80, CD86), major histocompatibility complex molecules (HLA-ABC, HLA-DR) and Fcgamma receptors (CD16, CD64) was examined by flow cytometry. Levels of blood monocytes secreting IL-6 and IL-12 were higher in patients with untreated MS and other neurological diseases (OND) compared to healthy controls, while levels of monocytes secreting TNF-alpha and IL-10 did not differ between groups. MS patients' blood monocytes also displayed elevated mean fluorescence intensity for the co-stimulatory molecule CD86, and MS patients with longer disease duration (>10 years) and higher disease severity (EDSS >3) had higher percentages of CD80 expressing monocytes compared to patients with short duration or lower severity. In conclusion, monocyte aberrations occur in MS and may change over the disease course.

IL-12 elispot assays to detect and enumerate IL-12 secreting cells

The cytokine IL-12 promotes Th(1)type immune responses and plays a key role in immune regulation. The complex nature of IL-12 hampered its detection without use of stimulants that might give less relevant information. To detect circulating IL-12 p40, we developed enzyme-linked immunospot (ELISPOT) assays that allow enumeration of IL-12 p40 secreting cells without prior in vitro stimulation of the cells. In parallel, intracellular staining of IL-12 p40 by flow cytometry was performed to compare the two methods. IL-12 p40 secreting cells were detected in healthy subjects at a mean number of 103+/-155 per 10(5)blood mononuclear cells (MNC). Numbers of IL-12 p40 secreting blood MNC correlated with IL-12 p40 positive blood MNC detected by flow cytometry. Bacterial endotoxins and the inflammatory cytokines TNF-alpha and IFN-gamma control IL-12 production by antigen presenting cells. Utilizing IL-12 p40 ELISPOT assays, we could confirm occurrence of elevated numbers of IL-12 p40 secreting blood MNC after stimulation with TNF-alpha, IFN-gamma, LPS, LPS+TNF-alpha or LPS+IFN-gamma, compared to cultures without stimulant. Due to its central role in inflammation and autoimmunity, IL-12 is an attractive target for immunotherapy. IL-12 p40 ELISPOT assays represent a sensitive, specific and reliable tool for investigating the role of IL-12 in both health and disease.

Multiple sclerosis: pro- and anti-inflammatory cytokines and metalloproteinases are affected differentially by treatment with IFN-beta

Interferon-beta (IFN-beta) has a beneficial influence on the course of multiple sclerosis (MS) and has become standard treatment of this disease, though its mechanisms of action are incompletely understood. This study examines the effect of IFN-beta treatment on the cytokines IL-6, TNF-alpha, IFN-gamma and IL-10; the metalloproteinases MMP-3, -7 and -9 and the tissue inhibitor of metalloproteinase-1 (TIMP-1). IFN-beta treatment resulted in decreased numbers of mononuclear cells (MNC) secreting IL-6 and TNF-alpha and expressing mRNA of MMP-3 and MMP-9 compared to pretreatment levels. On the contrary, numbers of IL-10 secreting MNC and TIMP-1 mRNA expressing were augmented during IFN-beta therapy. Whether the down-regulatory effects on pro-inflammatory and upregulatory effects on anti-inflammatory molecules are a direct result of IFN-beta on the immune system or secondary to clinical stabilization of MS pathology induced by IFN-beta remains to be evaluated.

Multiple sclerosis is associated with an imbalance between tumour necrosis factor-alpha (TNF-alpha)- and IL-10-secreting blood cells that is corrected by interferon-beta (IFN-beta) treatment

The up-regulated B cell responses detectable in cerebrospinal fluid (CSF) and the augmented myelin antigen-specific T cell responses observed in the CSF as well as systematically in patients with multiple sclerosis (MS) suggest the involvement of cytokines in disease development and perpetuation. Here we report on the parallel involvement of TNF-alpha, IL-6, IFN-gamma and IL-10 in MS and controls, using enzyme-linked immunospot (ELISPOT) assays to detect and enumerate cytokine-secreting mononuclear cells (MNC) prepared from blood and, for IL-6 and IL-10, from CSF without in vitro stimulation. MS is associated with elevated levels of TNF-alpha-secreting blood MNC when compared with levels in groups of control patients with myasthenia gravis (MG) and other neurological diseases (OND) or healthy subjects. This elevation was confined to patients with untreated MS and not present in those examined during ongoing treatment with IFN-beta. Untreated patients with MS had lower numbers of IL-10-secreting blood MNC compared with the three control groups. In patients undergoing treatment with IFN-beta, numbers of IL-10-secreting cells were in the same range as in controls. Normalization of TNF-alpha from elevated, and of IL-10 from decreased levels could be one reason for the beneficial effects of IFN-beta in MS, although it remains to be shown whether these changes reflect phenomena primarily involved in MS pathogenesis or secondary changes. In CSF, levels of IL-10-secreting cells were higher than in blood in both MS and OND, with no difference between these groups. Systemic aberrations of IL-6 and IFN-gamma and of IL-6 in CSF in MS versus controls were only minor, irrespective of treatment with IFN-beta.

Dealing with the subvoxel vessel position relative to the reconstruction voxel grid in 2D MR quantitative flow measurements

A method is introduced that quantifies the error in 2D MR Quantitative Flow measurements induced by the position of the vessel relative to the reconstruction voxel grid, called the subvoxel vessel position. In this method, the vessel area and the volume flow rate are determined for all possible subvoxel vessel positions resulting in a mean value with standard deviation. Since the subvoxel vessel position in standard MR image reconstruction is completely arbitrary, the standard deviation can be considered as a measure of its random error contribution. Simulation studies and in vivo measurements show that our method can be used to quantify and subsequently eliminate this random error. It is further quantitatively shown that, for low noise levels, Fourier interpolation to a higher reconstruction matrix also decreases the random error. We conclude that the precision of a 2D MR Quantitative Flow measurement is improved either by using our method or by reconstruction to a higher matrix.

Multiple sclerosis is associated with high levels of circulating dendritic cells secreting pro-inflammatory cytokines

Recent evidence emphasises a pivotal role for dendritic cells (DC) in the control of immunity by priming and tolerising T cells. DC capture and process antigens, express co-stimulatory molecules, migrate to lymphoid organs and secrete cytokines to initiate immune responses. In multiple sclerosis (MS), autoreactive T cells are proposed to play a pathogenic role by secreting pro-inflammatory cytokines, but studies on DC are lacking. To evaluate the involvement of DC in patients with MS, a modified procedure was used to prepare DC from blood of patients with MS and healthy subjects. DC were found to be potent stimulators of T cells in allogeneic and, to a lesser extent, in autologous mixed leukocyte reaction (MLR). Enzyme-linked immunospot (ELISPOT) assays were adopted to determine levels of IFN-gamma, TNF-alpha, IL-6 and IL-10 secreting DC vs. mononuclear cells (MNC). Proportionally more DC than MNC secreted IFN-gamma and IL-10 in both MS and healthy subjects. Patients with MS had higher levels of IFN-gamma, TNF-alpha and IL-6 secreting DC than healthy subjects. The differences for IFN-gamma and TNF-alpha secreting cells were confined to the subgroup of untreated MS patients and not observed in the subgroup examined during ongoing treatment with IFN-beta. Circulating DC secreting pro-inflammatory cytokines may represent another focus for the study of both immuno-pathogenesis and therapeutic interventions in MS.

Metalloproteinases and their tissue inhibitors in multiple sclerosis

Matrix metalloproteinases (MMPs) comprise a family of proteolytic enzymes. MMPs are capable of disrupting the blood-brain barrier (BBB), mediating the destruction of extracellular matrix and myelin components. MMPs are also involved in the processing of a variety of cell surface molecules, including the proinflammatory cytokine TNF-alpha. Each of these mechanisms are thought to be important in the pathogenesis of multiple sclerosis (MS). We investigated mRNA expression of MMP-3, MMP-9 and two tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) in parallel in blood mononuclear cells (MNC) from patients with MS and controls, using in situ hybridization. Numbers of MMP-9 mRNA-expressing cells in blood were higher in patients with MS compared to other neurological diseases (OND), other inflammatory neurological diseases (OIND) and healthy subjects (P<0.0001 for all comparisons). Patients with MS had also higher levels of MMP-3 and TIMP-1 mRNA expressing blood MNC compared to patients with OND and healthy subjects. A positive correlation was observed for MMP-9 and TIMP-1 mRNA expression in MS. These results demonstrate that MMPs and TIMPs are upregulated in MS and may contribute to the pathogenesis of the disease.

Multiple sclerosis: levels of interleukin-10-secreting blood mononuclear cells are low in untreated patients but augmented during interferon-beta-1b treatment

The cytokine interleukin (IL)-10 has immune response down-regulatory properties, which include suppression of the synthesis of pro-inflammatory cytokines such as interferon (IFN)-gamma and of major histocompatibility complex (MHC) class II expression on monocytes. To further elucidate the involvement of IL-10 in multiple sclerosis (MS), an enzyme-linked immunospot assay was adopted to enumerate IL-10-secreting mononuclear cells (MNC) in peripheral blood. IFN-gamma secreting MNC were detected in parallel. Levels of IL-10-secreting cells were lower in patients with MS compared with other neurological diseases (OND) and healthy subjects. This difference was seen only in patients with untreated MS, and not in those undergoing treatment with IFN-beta-1b. No differences were observed when subgrouping the patients with MS regarding clinical phase (exacerbation, remission, secondary progression), duration of MS or disability status. Levels of IFN-gamma-secreting blood MNC did not differ in patients with MS, irrespective of treatment with IFN-beta-1b, compared with OND and healthy subjects. Patients with MS, but not the two groups of controls, had elevated numbers of IL-10- and IFN-gamma-secreting cells upon stimulation with MBP compared with culture in the absence of antigen. The data suggest that IL-10 is decreased in MS and that treatment resulting in its up-regulation beneficially influence the disease.

Stepping-table gadolinium-enhanced digital subtraction MR angiography of the aorta and lower extremity arteries: preliminary experience

PURPOSE

To compare stepping-table digital subtraction gadolinium-enhanced magnetic resonance (MR) angiography of the distal aorta and lower extremity arteries with conventional catheter digital subtraction x-ray angiography in patients with arterio-occlusive disease.

MATERIALS AND METHODS

Twenty patients underwent both conventional catheter angiography and fast three-dimensional gadolinium-enhanced MR angiography of the aorta and outflow vessels at 1.5 T; the images were acquired in three consecutive imaging locations during a single infusion of a gadolinium chelate.

RESULTS

Compared with catheter angiography, according to the findings of two blinded independent reviewers, MR angiography had sensitivities of 81% and 89% and specificities of 91% and 95%, respectively, for demonstration of insignificant (< or = 50%) stenosis versus significant (51%-100%) stenosis. For demonstration of occlusion, the sensitivity and specificity were 94% and 97%, respectively, by consensus. There was good interobserver correlation between the two readers overall (kappa = 0.65 for reporting the degree of narrowing in all lesions; 0.86, for reporting of insignificant versus significant stenoses; and 0.928, for reporting of occluded versus patient segments).

CONCLUSION

Stepping-table digital subtraction contrast material-enhanced MR angiography has high accuracy compared with catheter angiography in patients with arterio-occlusive disease of the aorta and outflow vessels. These preliminary study results suggest that this technique may ultimately provide a safe, noninvasive, and cost-effective alternative to catheter angiography.

Contrast-enhanced MR angiography. Methods, limitations and possibilities

Whereas conventional MRA relies on enhanced blood signal from flow-induced magnitude and/or phase effects, gadolinium-enhanced MRA relies mainly on the enhanced blood signal caused by the reduced relaxation time T1. This has a large impact on the imaging technique used, as well as on the imaging volume orientation and the total scanning time. In general, gadolinium-enhanced MRA is faster, with fewer artifacts than MRA without contrast agents.

Systolically gated 3D phase contrast MRA of mesenteric arteries in suspected mesenteric ischemia

OBJECTIVE

Our goal was to assess the value of MRA for detecting stenoses in the celiac (CA) and superior mesenteric (SMA) arteries in patients suspected of having chronic mesenteric ischemia, using an optimized systolically gated 3D phase contrast technique.

MATERIALS AND METHODS

In an initial study in 24 patients who underwent conventional angiography of the abdominal vessels for different clinical indications, a 3D phase contrast MRA technique (3D-PCA) was evaluated and optimized to image the CAs and SMAs. Subsequently, a prospective study was performed to assess the value of systolically gated 3D-PCA in evaluation of the mesenteric arteries in 10 patients with signs and symptoms of chronic mesenteric ischemia. Intraarterial digital subtraction angiography and surgical findings were used as the reference standard.

RESULTS

In the initial study, systolic gating appeared to be essential in imaging the SMA on 3D-PCA. In 10 patients suspected of mesenteric ischemia, systolically gated 3D-PCA identified significant proximal disease in the two mesenteric vessels in 4 patients. These patients underwent sucessful reconstruction of their stenotic vessels.

CONCLUSION

Cardiac-gated MRA may become a useful tool in selection of patients suspected of having mesenteric ischemia who may benefit from surgery.

Renovascular disease in patients with hypertension: detection with systolic and diastolic gating in three-dimensional, phase-contrast MR angiography

PURPOSE

To evaluate the usefulness of three-dimensional, phase-contrast magnetic resonance (MR) angiography performed with cardiac synchronization in the assessment of renal arteries.

MATERIALS AND METHODS

Thirty-eight patients (24 men, 14 women) underwent three-dimensional, phase-contrast MR angiography without gating and with systolic and diastolic gating. Conventional angiography was used as the standard of reference.

RESULTS

The sensitivity for the detection of all stenoses (> 0%) was 93% with systolic, 92% with diastolic, and 77% without gating. However, there was no difference between the three techniques in the diagnosis of hemodynamically significant stenoses (> 50%). The mean arterial length depicted was significantly better with diastolic gating than with either of the other techniques (P < .0001). Vascular disease was significantly overestimated with systolic gating relative to estimation without (P = .030) or with diastolic (P = .008) gating.

CONCLUSION

Three-dimensional, phase-contrast MR angiography provides good image quality and enables assessment of renovascular disease. Cardiac gating has limited improvement of these results.