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Ron Shnier

Publications and source records attributed to Ron Shnier.

17 recordsLinked to original sources
PubMed2006

Reduced activation to implicit affect induction in euthymic bipolar patients: an fMRI study.

OBJECTIVE: To examine whether euthymic bipolar patients engage similar or contrasting brain regions as healthy subjects when responding to implicit affect induction. METHODS: The study examined 10 euthymic patients with bipolar I disorder, and 10 age- and gender-matched healthy subjects using event-related functional magnetic resonance imaging (fMRI) while subjects engaged in a modified word-based memory task designed to implicitly evoke negative, positive or no affective change. The activation paradigm involved nominating whether a target word was contained within a previously presented word list using specified response keys. RESULTS: The fMRI task produced significantly greater activation in healthy subjects as compared to patients in response to both negative and positive affect in the anterior and posterior cingulate, medial prefrontal cortex, middle frontal and right parahippocampal gyri. Only negative affect produced significantly greater activation in the postcentral gyrus, inferior parietal lobule, thalamus and putamen and only positive affect achieved the same in the precentral, superior temporal and lingual gyri, precuneus, cuneus, caudate, pons, midbrain and cerebellum. There were no brain regions in which responses were greater in patients as compared to healthy subjects. There were no statistically significant differences between the groups with respect to speed or accuracy. CONCLUSIONS: Diminished prefrontal, cingulate, limbic and subcortical neural activity in euthymic bipolar patients as compared to healthy subjects is suggestive of emotional compromise that is independent of cognitive and executive functioning. This finding is of clinical importance and has implications both for the diagnosis and treatment of bipolar disorder. Future studies should aim to replicate these findings and examine the development of bipolar disorder, investigating in particular the effects of medication.

Adult↗
PubMed2006

Synovial membrane cytokine expression is predictive of joint damage progression in rheumatoid arthritis: a two-year prospective study (the DAMAGE study cohort).

OBJECTIVE: The primary aim of this prospective 2-year study was to explain the wide variability in joint damage progression in patients with rheumatoid arthritis (RA) from measures of pathologic changes in the synovial membrane. METHODS: Patients underwent clinical measurements and joint damage assessments by magnetic resonance imaging (MRI) and radiography at enrollment and at year 2. Synovial membrane was obtained by knee biopsy and assessed histologically by hematoxylin and eosin staining. Interleukin-1beta (IL-1beta), IL-10, IL-16, IL-17, RANKL, tumor necrosis factor alpha (TNFalpha), and interferon-gamma (IFNgamma) messenger RNA (mRNA) expression was determined by quantitative reverse transcription-polymerase chain reaction. The relationship of synovial measurements to joint damage progression was determined by multivariate analysis. RESULTS: Sixty patients were enrolled. Histologic features had no relationship to damage progression. Multivariate analysis by several different methods consistently demonstrated that synovial membrane mRNA levels of IL-1beta, TNFalpha, IL-17, and IL-10 were predictive of damage progression. IL-17 was synergistic with TNFalpha. TNFalpha and IL-17 effects were most pronounced with shorter disease duration, and IL-1beta effects were most pronounced with longer disease duration. IFNgamma was protective. These factors explained 57% of the MRI joint damage progression over 2 years. CONCLUSION: We have demonstrated for the first time in a prospective study that synovial membrane cytokine mRNA expression is predictive of joint damage progression in RA. The findings for IL-1beta and TNFalpha are consistent with results of previous clinical research, but the protective role of IFNgamma, the differing effects of disease duration, and IL-17-cytokine interactions had only been demonstrated previously by animal and in vitro research. These findings explain some of the variability of joint damage in RA and identify new targets for therapy.

Adult↗
PubMed2005

An emotional Stroop functional MRI study of euthymic bipolar disorder.

OBJECTIVE: To identify the brain regions associated with emotional processing in euthymic bipolar patients. METHODS: The study examined 12 euthymic bipolar patients using functional magnetic resonance imaging (fMRI) while performing an emotional Stroop (eStroop) task. The task comprised emotionally valent and neutral words presented in alternating blocks that was designed to implicitly induce affect. In conjunction with fMRI, galvanic skin responses (GSR) were measured to monitor arousal. RESULTS: Euthymic bipolar patients had diminished activation in response to the affective stimuli in both cortical and subcortical brain regions when compared with healthy subjects. In particular, patients had less activation in the left ventral prefrontal cortex suggesting a potential trait deficit. Patients were slower to react than healthy controls, but did not differ with respect to accuracy. CONCLUSIONS: Euthymic bipolar patients are perhaps constrained in their ability to engage affective processing. Diminished ventral prefrontal cortex activation corroborates previous reports of a potential trait deficit, suggesting that 'all is not well in euthymia', although the effects of medication cannot be overlooked.

Adult↗
PubMed2005

Training and calibration improve inter-reader reliability of joint damage assessment using magnetic resonance image scoring and computerized erosion volume measurement.

OBJECTIVE: To assess the inter-reader reliability of 3 rheumatologist readers before and after training using 2 methods of assessment: magnetic resonance imaging (MRI) computerized erosion volume assessment and MRI scoring using the OMERACT-5 Rheumatoid Arthritis MRI Score (OM-5 RAMRIS) criteria. METHODS: Erosion volumes were measured in 10 patients [5 wrist and 5 metacarpophalangeal (MCP) joint studies] with rheumatoid arthritis. Erosion scores were derived from this group and 8 additional subjects to provide a total of 18 subjects (10 wrist and 8 MCP joint studies) with MRI scores for comparison. Subjects were selected from existing MRI databases to provide a spectrum of joint damage for assessment. Initial reading was undertaken after the 2 inexperienced readers were provided with instructions regarding OSIRIS computer software and definitions of the OMERACT score; no other formal training was undertaken. One month after the initial reading, the 2 inexperienced readers undertook a 3 hour training session and all 3 readers then took part in 2 subsequent 2 hour calibration sessions. Each reader then reread the original MRI studies using the computerized erosion volume method and the OMERACT MRI RA score. The interval between the baseline and post-training reading was 2 months. All reading was undertaken on a computer workstation and readers were blinded to other readers' results. RESULTS: For the wrist MRI studies, inter-reader agreement improved considerably after training for both the computerized MRI volume method and the OMERACT MRI score [intraclass correlation coefficients (ICC) 0.21 and 0.46, respectively, pre-training; 0.92 and 0.85 post-training]. The correlation between all readers' scores and volumes was excellent at baseline and post-training. For the MCP joint studies, inter-reader agreement was moderate at baseline for the erosion volume and score (ICC 0.51 and 0.61). While there was some improvement in agreement post-training for the scoring method (ICC 0.75), there was no significant improvement for the erosion volumes (ICC 0.58). CONCLUSION: Overall, inter-reader agreement for erosion scoring and volume measurement was higher for the wrist joint. The lack of improvement in the MCP joint region for the erosion volume measurements appears to relate primarily to difficulties in estimating the erosion border in the proximal MCP joints using the manual outlining tool. This limits the usefulness of erosion volume measurements in this joint region.

Arthritis, Rheumatoid↗
PubMed2004

Documenting damage progression in a two-year longitudinal study of rheumatoid arthritis patients with established disease (the DAMAGE study cohort): is there an advantage in the use of magnetic resonance imaging as compared with plain radiography?

OBJECTIVE: In early rheumatoid arthritis (RA), longitudinal studies have demonstrated that magnetic resonance imaging (MRI) is more sensitive than radiography in demonstrating progressive erosive joint damage. The present study evaluated the progression of erosive damage in patients with established RA by using limited field of view MRI and comparing the results with those obtained by radiography. METHODS: MRI and radiographic studies were available from 47 of 60 patients enrolled in a 2-year RA observational study. MRI of the metacarpophalangeal (MCP) joints was performed at baseline and 2 years later, and a single observer scored all of the MR images with the use of an MRI scoring method developed by the Outcome Measures in Rheumatology Clinical Trials MRI RA study group. MR images from 14 patients were reread by the same observer after 1 week to assess intraobserver reliability. Radiographs were obtained at baseline and at 2 years, and were scored by an observer using the Scott modification of the Larsen score. Radiographs from 14 patients were reread after 1 week to assess the intraobserver reliability. The smallest detectable difference (SDD) was calculated for the MRI scores, the total Larsen scores, and the Larsen scores of the dominant-hand MCP joints (MCPs 2-5) for direct comparison with the MRI results. RESULTS: The median disease duration was 5.1 years (range 0.5-29 years). Evidence of erosion progression was identified by MRI in 30 patients (64%). The SDD based on the intraobserver scores was calculated as +/-3.25 units. Using this result, 11 patients (23%) showed evidence of erosion progression on MRI that was greater than the SDD. The SDD for progression based on the intraobserver total Larsen radiographic scores was 0.77 units, and the SDD for the Larsen scores of the dominant-hand MCP joints was 1.55 units. On the basis of these results, radiographic progression was noted in 19 patients (40%) by the total Larsen score and 7 patients (15%) by the dominant-hand MCP Larsen score. The most striking finding was that although MRI and radiograph scores identified a similar group of patients as having progression of joint damage, the radiographs of both hands appeared to be more responsive to change, albeit with the caveat that radiographic progression was most marked outside the dominant-hand MCP joints. CONCLUSION: There was no clear advantage of MRI with a limited field of view as compared with radiographic imaging of both hands in detecting progression of joint damage over 2 years in this group of patients with established RA. The conclusion drawn from this study is not that radiographs are better than MRI or vice versa, but that careful analysis is required to determine the optimal imaging method, or combination of imaging methods, for each study population, depending on the objective and duration of the study.

Arthritis, Rheumatoid↗
PubMed2004

Effect of white matter hyperintensities on cortical cerebral blood volume using perfusion MRI.

White matter hyperintensities (WMHs) are commonly seen on brain magnetic resonance imaging (MRI) scans of elderly individuals, but their functional significance remains controversial. We used perfusion-weighted MRI to determine the impact of WMHs on cortical regional cerebral blood volume (rCBV). We studied 24 elderly stroke patients and 27 control subjects with conventional MRI which included T2-weighted FLAIR coronal slices through whole brain and gadolinium-DTPA (0.2 mmol/kg)-based perfusion MRI (pMRI) with echo planar imaging. Volumes of WMHs, including deep WMHs and periventricular hyperintensities (PVHs), were computed by an automated method after excluding regions of infarction. Partial correlations between WMH and corresponding cortical rCBV were determined after correction for age and atrophy. The relative rCBV of gray matter was higher in control subjects and there was no significant hemispheric asymmetry. When both stroke and control groups were included, there were significant correlations among frontal cortical rCBV and frontal WMHs, temporal cortical rCBV with temporal WMHs, and cortical rCBV with both total deep WMHs and PVHs. Although the trends of correlation still existed when the two groups were analyzed separately, they were not significant. The correlations between cortical rCBV and WMHs in the same lobe were significant for subjects with more severe hyperintensities irrespective of the group. In conclusion, T2-weighted WMHs are associated with reduced rCBV in the cerebral cortex, particularly in individuals with extensive hyperintensities.

Age Factors↗
PubMed2004

Cerebral blood volume in T2-weighted white matter hyperintensities using exogenous contrast based perfusion MRI.

We used perfusion weighted magnetic resonance imaging (MRI) to determine relative regional cerebral blood volume (rCBV) in regions of white matter hyperintensity (WMH) in 28 elderly stroke patients and 27 healthy comparison subjects, using T2-weighted fluid-attenuated inversion recovery (FLAIR) sequence MRI for anatomical localization and bolus gadolinium-DTPA tracking for perfusion weighted imaging. We found that WMHs had significantly lower rCBV than contralateral normal WMH, irrespective of size or group membership, and rCBV was significantly related to the size of the WMH. For the larger WMHs, there was a significant increase in rCBV from inner core to outer ring. The findings suggest hemodynamic perturbation in the microvasculature of hyperintense regions, which becomes greater as the size of the WMH increases. This is equally applicable to stroke patients and healthy older individuals.

Aged↗
PubMed2004

Diagnostic values of tests for acromioclavicular joint pain.

BACKGROUND: This prospective study was performed to determine which clinical and imaging tests were most helpful for diagnosing acromioclavicular joint pain. METHODS: Of 1037 patients with shoulder pain, 113 who mapped pain within an area bounded by the midpart of the clavicle and the deltoid insertion were eligible for inclusion in the study. Forty-two subjects agreed to participate, and four of them were lost to follow-up. Twenty clinical tests, radiography, bone-scanning, magnetic resonance imaging, and an acromioclavicular joint injection test were performed on all patients. The patients were divided into two groups according to whether they had a > or =50% decrease in pain following the acromioclavicular joint injection. Statistical analysis, including multivariate regression analysis, was performed in order to evaluate the diagnostic effectiveness of the various tests. RESULTS: Acromioclavicular joint pain was confirmed in twenty-eight of the thirty-eight patients. The most sensitive tests were examination for acromioclavicular tenderness (96% sensitivity), the Paxinos test (79%), magnetic resonance imaging (85%), and bone-scanning (82%), but these studies had low specificity. In the stepwise regression model, with the response to the injection used as the dependent variable, bone-scanning and the Paxinos test were the only independent variables retained. Patients with a positive Paxinos test as well as a positive bone scan had high post-test odds (55:1) and a 99% post-test probability of having pain due to pathological changes in the acromioclavicular joint. The likelihood ratio for patients with one negative test and one positive test was indeterminate (0.4:1). Patients with both a negative Paxinos test and a negative bone scan had a likelihood ratio of 0.03:1 for having acromioclavicular joint pain, which basically rules out the disorder. CONCLUSIONS: The highly sensitive tests had low specificity, and the highly specific tests had low sensitivity. However, the combination of a positive Paxinos test and a positive bone scan predicted damage to the acromioclavicular joint as the cause of shoulder pain with a high degree of confidence.

Acromioclavicular Joint↗
PubMed2003

Computerized measurement of magnetic resonance imaging erosion volumes in patients with rheumatoid arthritis: a comparison with existing magnetic resonance imaging scoring systems and standard clinical outcome measures.

OBJECTIVE: One of the major aims of therapy in rheumatoid arthritis (RA) is to prevent erosive disease and subsequent disability. One of the important goals of therapy assessment must therefore be the accurate measurement of damage progression. We undertook this study to assess the feasibility, reliability, and validity of measuring magnetic resonance imaging (MRI) erosion volumes and synovial volumes in the wrists of RA patients with the use of a semiautomated computerized method. METHODS: Twelve subjects with seropositive RA were chosen to reflect a spectrum of RA severity as determined by the clinical Joint Alignment and Motion (JAM) Scale. MRI of the dominant wrist was performed at the same time of day at baseline and at 48 hours. Images were transferred to a workstation. Erosion volumes and synovial volumes were measured on the coronal images using OSIRIS imaging software. All images were reread in random order at 72 hours by 1 observer. The results were compared with erosion scores and global synovitis scores obtained by the same observer using the Outcome Measures in Rheumatology Clinical Trials MRI RA scoring system. Radiographs were performed at baseline and were read on 2 occasions by 1 observer using the Scott modification of the Larsen method. RESULTS: Total erosion volume per subject ranged from 0 cm(3) to 4.7 cm(3). The total synovial membrane volume per subject ranged from 0.1 mm(3) to 12.1 cm(3). Intraclass correlation coefficients for erosion volumes and synovial volumes demonstrated excellent intraobserver reliability and interoccasion reliability. There was a strong positive correlation between the total erosion volume and the total erosion score. The correlation between the synovial volumes and synovitis score was less favorable (r = 0.53-0.86). Positive correlations were demonstrated between the erosion volumes, the JAM score, and the modified Larsen scores. No significant correlation was demonstrated between the erythrocyte sedimentation rate, C-reactive protein level, swollen joint count, tender joint count, or the Disease Activity Score in 28 swollen and 28 tender joints and the synovial volumes or synovitis scores. CONCLUSION: This study is the first to demonstrate the feasibility, reliability, and validity of computerized MRI erosion volume measurements in the wrists of RA patients. The method will require further evaluation in terms of interobserver reliability, with examination of responsiveness in longitudinal studies, but the method demonstrates excellent interoccasion and intraobserver reliability and compares favorably with existing RA clinical outcome measures. Synovial volume measurements demonstrated good intraobserver reliability and appeared to be more responsive to synovial change over a 48-hour period in this group of patients.

Adult↗
PubMed2003

OMERACT Rheumatoid Arthritis MRI Studies Module.

The rationale for an OMERACT Module on the use of magnetic resonance imaging (MRI) in the assessment of rheumatoid arthritis (RA) is outlined. This article also details the way in which the RA MRI Working Group developed and undertook a series of structured exercises to evaluate the reliability and sensitivity to change of the RA-MRI score (RAMRIS).

Arthritis, Rheumatoid↗
PubMed2003

OMERACT Rheumatoid Arthritis Magnetic Resonance Imaging Studies. Exercise 3: an international multicenter reliability study using the RA-MRI Score.

We examined inter-reader agreement of the revised OMERACT 5 Rheumatoid Arthritis MRI Score (RAMRIS v3). Magnetic resonance (MR) images of 10 sets of metacarpophalangeal (MCP) joints 2-5 and 8 sets of rheumatoid arthritis (RA) wrists [1.5 T, coronal and axial T1 and T2 spin-echo, +/- fat saturation (FS), +/- intravenous gadolinium (Gd)] were scored for (1) synovitis using a global score (0-3) and a direct measurement of synovial thickness (mm) and (2) three bone lesions: erosions, defects and edema, (score 0-10 by the volume of the lesion as a proportion of the "assessed bone volume" by 10% increments). Six readers from 5 multinational centers performed all scoring. Three statistical methods were used to analyze the data: (1) single-measure fixed effects intraclass correlations (sICC) and average-measure fixed effects ICC (avICC), (2) percentage exact and close agreement, and (3) the smallest detectable difference (SDD). The sICC were moderate to good (between 0.60 and 0.91) for half of the joint sites for the 2 synovitis scoring methods, and for bone erosions and bone edema. After adjusting for 6 readers, the avICC was very good to excellent (0.80-0.98) for two-thirds of the joint sites by lesion, excluding bone defects that performed relatively poorly, primarily because few readers scored these lesions. The aggregated scores with the best reliability were those with a wide range of scores, high ICC, low SDD, and low percentage SDD (< 33%). The metacarpophalangeal (MCP) bone erosion (sICC 0.58, avICC 0.89, %SDD +/- 27), wrist bone erosion scores (0.72, 0.94, +/- 31%), the wrist synovitis global (0.74, 0.94, +/- 32%), and synovial maximal thickness (0.6, 0.94, +/- 32%) met these conditions. MCP joint synovitis global (0.76, 0.95, +/-35%), MCP joint bone edema (0.63, 0.91, +/- 34%), and wrist bone edema (0.78, 0.95, +/- 38%) performed marginally less well. Bone defects performed poorly (MCP joint 0.18, 0.46, +/- 56%; wrist 0.06, 0.24, +/- 55%). The revised OMERACT 5 RAMRIS has acceptable inter-reader reliability for measures of disease activity (synovitis global and bone edema scores) and damage (bone erosion score). Whether the score is sensitive to change will be determined by its performance in longitudinal and intervention studies.

Arthritis, Rheumatoid↗
PubMed2003

OMERACT Rheumatoid Arthritis Magnetic Resonance Imaging Studies. Exercise 4: an international multicenter longitudinal study using the RA-MRI Score.

The aim of this multireader, multicenter study was to assess the inter-reader reliability of the score in the assessment of disease status and progression. The exercise involved 10 sets of metacarpophalangeal (MCP, 2nd to 5th) joints and 10 sets of wrist magnetic resonance images that were scored by experienced readers from 5 international centers. Synovitis was scored for each site using a global score (0-3). Bone abnormalities were assessed at 8 MCP joint sites and 15 wrist sites according to proportion of bone volume (0-10 for erosions and defects and 0-3 for edema). Intraclass correlation coefficients (ICC) and smallest detectable differences for synovitis, erosions, and edema were acceptable, although better for status scores than progression scores. The agreement for MCP joints was better than wrists. Limited variation in the images for some findings resulted in low ICC. Bone defects had the poorest agreement and have been omitted from new scoring recommendations. Despite limited training, multicenter readers demonstrated acceptable levels of agreement.

Arthritis, Rheumatoid↗
PubMed2003

OMERACT Rheumatoid Arthritis Magnetic Resonance Imaging Studies. Core set of MRI acquisitions, joint pathology definitions, and the OMERACT RA-MRI scoring system.

This article describes the 2002 OMERACT rheumatoid arthritis magnetic resonance image scoring system (RAMRIS) for evaluation of inflammatory and destructive changes in RA hands and wrists, which was developed by an international MRI-OMERACT group. MRI definitions of important RA joint pathologies, and a "core set" of basic MRI sequences for use in RA are also suggested.

Arthritis, Rheumatoid↗
PubMed2003

OMERACT Rheumatoid Arthritis Magnetic Resonance Imaging Studies. Summary of OMERACT 6 MR Imaging Module.

Magnetic resonance image (MRI) scanning is a new method for imaging and quantifying joint inflammation and damage in rheumatoid arthritis (RA). Over the past 4 years, the OMERACT MR Imaging Group has been developing and testing the RA-MRI scoring system (RAMRIS) for use in RA. The OMERACT filter demands that an ideal outcome measure satisfy the elements of truth, discrimination, and feasibility. The RAMRIS as it currently stands incorporates measures of joint inflammation and damage including bone erosion, edema, and synovitis. Tendonitis has not been scored because of feasibility issues; joint space narrowing, reflecting cartilage damage, has also been excluded as reliability was low at the small joints of the hands. Anatomical coverage of the score is currently restricted to the wrists and hands but can provide a basis for a more comprehensive score. The MR measurement of synovitis correlates closely with histological evidence and work continues on validating MR erosions with reference to radiographic techniques. The RAMRIS has demonstrated good reliability for bone erosion and synovitis at the wrists and metacarpophalangeal joints subject to reader training, with slightly lower levels of reader agreement for bone edema. Reliability was less satisfactory in discriminating between 2 time points, and further work is required if the score is to be used to monitor change. Feasibility also needs to be considered for the practical application of the score, including the time taken for scanning and scoring, as well as cost and safety issues. The OMERACT RAMRIS provides a framework for scoring inflammation and damage in RA upon which further modifications can be built. It has been endorsed by the MRI working group and OMERACT 6 participants as useful for inclusion as an outcome measure in clinical trials.

Arthritis, Rheumatoid↗
PubMedDate not supplied

A comparison of clinical estimation, ultrasonography, magnetic resonance imaging, and arthroscopy in determining the size of rotator cuff tears.

This prospective study was undertaken to compare the ability of clinical estimation, diagnostic ultrasonography, magnetic resonance imaging, and arthroscopy to estimate the size of rotator cuff tears. Estimates of rotator cuff tear size were compared with the findings at open operation in 33 consecutive patients with a presumptive diagnosis of rotator cuff tear. Arthroscopy estimates of rotator cuff tear size correlated best with actual tear size (Pearson correlation coefficient r = 0.92; P <.001). Magnetic resonance imaging (r = 0.74; P <.001) was similar to ultrasonography (r = 0.73; P <.001). Estimates of rotator cuff tear size after clinical assessment alone had weaker correlation coefficients (r = 0.41; P =.02) than the other methods. Each method underestimated rotator cuff tear size by 12%, 30%, 33%, and 38%, respectively. No method was able to determine the size of partial-thickness rotator cuff tears (r < 0.02).

Aged↗