Magnetic resonance imaging of idiopathic carpal tunnel syndrome: Correlation with clinical findings and electrophysiological investigation

Objective: To compare clinical evaluation, electrophysiological investigation and magnetic resonance findings in assessing the severity of idiopathic carpal tunnel syndrome. Patients and methods: Seventy-four patients with idiopathic carpal tunnel syndrome were prospectively recruited. Clinical evaluation included symptoms severity score and two-point discrimination, sensory and motor nerve conduction velocities were determined by electroneuromyography and imaging parameters were obtained after wrist magnetic resonance. The Wilcoxon test was used to define the differences between measurements of median nerve area. The Pearson and Spearman correlation tests were used to determine the relationships between all the measured parameters. Results: Cross-sectional area of median nerve was smaller at hamate level than at radio-ulnar joint and pisiform levels (p < 0.001). With exception of median nerve area at hamate level, there was a lower degree of correlation between MRI parameters and findings obtained by clinical assessments and electrophysiological measurements. The median nerve area at hamate level correlated negatively with duration of symptoms, two-point discrimination, symptoms severity score and positively with sensory nerve conduction velocity (P < 0.01). Conclusion: In patients with idiopathic carpal tunnel syndrome, median nerve area measured by wrist magnetic resonance at hamate level may be considered as a valuable indicator to grading the severity of disease. (c) 2007 Elsevier B.V. All rights reserved.

Correlation between macular and retinal nerve fibre layer Fourier-domain OCT measurements and visual field loss in chiasmal compression

Purpose The aim of this study was to test the correlation between Fourier-domain (FD) optical coherence tomography (OCT) macular and retinal nerve fibre layer (RNFL) thickness and visual field (VF) loss on standard automated perimetry (SAP) in chiasmal compression. Methods A total of 35 eyes with permanent temporal VF defects and 35 controls underwent SAP and FD-OCT (3D OCT-1000; Topcon Corp.) examinations. Macular thickness measurements were averaged for the central area and for each quadrant and half of that area, whereas RNFL thickness was determined for six sectors around the optic disc. VF loss was estimated in six sectors of the VF and in the central 16 test points in the VF. The correlation between VF loss and OCT measurements was tested with Spearman`s correlation coefficients and with linear regression analysis. Results Macular and RNFL thickness parameters correlated strongly with SAP VF loss. Correlations were generally stronger between VF loss and quadrantic or hemianopic macular thickness than with sectoral RNFL thickness. For the macular parameters, we observed the strongest correlation between macular thickness in the inferonasal quadrant and VF loss in the superior temporal central quadrant (rho=0.78; P<0.001) whereas for the RNFL parameters the strongest correlation was observed between the superonasal optic disc sector and the central temporal VF defect (rho=0.60; P<0.001).

Statistical questions - Comment

No Abstract

Quality of life and neuropsychological changes in mild head trauma - Late analysis and correlation with S100B protein and cranial CT scan performed at hospital admission

Introduction: mild head trauma (MHT) is defined as a transient neurological deficit after trauma with a history of impairment or loss of consciousness lasting less than 15 min and/or posttraumatic amnesia, and a Glasgow Coma Scale between 13 and 15 on hospital admission. We evaluated 50 MHT patients 18 months after the trauma, addressing signs and symptoms of post-concussion syndrome, quality of life and the presence of anxiety and depression. We correlate those findings with the S100B protein levels and cranial CT scan performed at hospital admission after the trauma. Method: patients were asked to fill out questionnaires to assess quality of life (SF36), anxiety and depression (HADS), and signs and symptoms of post-concussion syndrome. For the control group, we asked the patient`s household members, who had no history of head trauma of any type, to answer the same questionnaires for comparison. Results: total quality of life index for patients with MHT was 58.16 (+/-5), lower than the 73.47 (+/-4) presented by the control group. Twenty patients (55.2%) and four (11.1%) controls were depressed. Seventeen patients (47.2%) presented anxiety, whereas only eight (22.2%) controls were considered anxious. Victims of MHT complained more frequently of loss of balance, dry mouth, pain in the arms, loss of memory and dizziness than their respective controls (p < 0.05). We found no correlation between the presence of these signs and symptoms, quality of life, presence of anxiety and depression with S100B protein levels or with presence of injury in the cranial CT performed at hospital admission. Conclusion: MHT is associated with a higher incidence of post-concussion syndrome symptoms, lower quality of life and anxiety than their respective controls even 18 months after the trauma. (C) 2007 Elsevier Ltd. All rights reserved.

A prospective study evaluating the efficacy of the artificial sphincter AMS 800 for the treatment of postradical prostatectomy urinary incontinence and the correlation between preoperative urodynamic and surgical outcomes

OBJECTIVES We have evaluated prospectively the long-term efficacy of the artificial urinary sphincter (AUS) AMS 800 for the treatment postradical prostatectomy urinary incontinence (PRPUI) patients. We also evaluated the correlation between preoperative urodynamic findings and surgical outcomes. METHODS From May 1997 to April 2003, 40 consecutive patients with PRPUI caused by intrinsic sphincter deficiency (ISD) were treated with the AMS 800. Mean age was 68.3 +/- 6.3 years. Continence status was evaluated on the basis of pad count, impact of urinary incontinence on the quality of life, complications, and surgical revisions. Preoperative urodynamic findings were correlated with surgical outcomes. RESULTS Follow-up ranged from 27 to 132 months (mean = 53.4 +/- 21.4 months). There was a significant reduction in pad count from 4.0 +/- 0.9 to 0.62 +/- 1.07 diapers per day (P <0.001) leading to continence in 90%. There was a significant reduction on the impact of incontinence decreasing from 5.0 +/- 0.7 to 1.4 +/- 0.93 (P <0.001) in a visual analogue scale (VAS). Surgical revision rate was 20%. Preoperative urodynamics was useful to identify sphincter deficiency. Except by a tendency of worse results in patients with reduced bladder compliance (RBC), other urodynamic parameters did not correlate with a worse surgical outcome. CONCLUSIONS The AMS 800 offers good long-term continence to most PRPUI patients. Preoperative findings like detrusor hyperactivity (DH), impaired detrusor contraction (IDC), low Valsalva leak point pressure, bladder outlet obstruction (BOO), and mild RBC were not associated with worse surgical outcomes.

Correlation between the Body Mass Index (BMI) of Pregnant Women and the Development of Hypotension after Spinal Anesthesia for Cesarean Section

Nani FS, Torres MLA - Correlation between the Body Mass Index (BMI) of Pregnant Women and the Development of Hypotension after Spinal Anesthesia for Cesarean Section. Background and objectives: Very few publications correlate hypotension in obese pregnant women, and especially morbidly obese, after spinal anesthesia for cesarean section. The objective of the present study was to evaluate the incidence of hypotension according to the BMI. Methods: Forty-nine patients with pregestational BMI below 25 kg.m(-2) were included in the Eutrophia group, and 51 patients with BMI >= 25 kg.m(-2) were included in the Overweight group. After spinal anesthesia, blood pressure, volume of crystalloid infused, and dose of vasopressors used until delivery were recorded. A fall in systolic blood pressure below 100 mmHg or 10% reduction of the initial systolic blood pressure (SBP) was considered as hypotension and it was corrected by the administration of vasopressors. Results: Episodes of hypotension were fewer in the Eutrophia group (5.89 +/- 0.53 vs. 7.80 +/- 0.66, p = 0.027), as well as the amount of crystalloid administered (1,298 +/- 413.6 mL vs. 1,539 +/- 460.0 mL; p = 0.007), and use of vasopressors (5.87 +/- 3.45 bolus vs. 7.70 +/- 4.46 bolus; p = 0.023). As for associated diseases, we observed higher incidence of diabetes among obese pregnant women (29.41% vs. 9.76%, RR 1.60, 95%CI: 1.15-2.22, p = 0.036), however, differences in the incidence of pregnancy-induced hypertension (PIN) were not observe between both groups (overweight: 21.57%, normal weight: 12.20%, RR 1.30, 95%CI: 0.88-1.94, p = 0.28). Conclusions: In the study sample, pregestational BMI >= 25 kg.m(-2) was a risk factor for hypotension after spinal anesthesia in patients undergoing cesarean section. The same group of patients required higher doses of vasopressors. Those results indicate that the anesthetic techniques in those patients should be improved to reduce the consequences of post-spinal anesthesia hypotension, both in pregnant women and fetuses.

Prevalence of Metabolic Syndrome in Patients With Intermittent Claudication and its Correlation With the Segment of Arterial Obstruction

The metabolic syndrome (MetS) is associated with increased cardiovascular morbidity and mortality. Intermittent claudication reflects the presence of peripheral arterial disease (PAD). The aim of this study is to determine the prevalence of the MetS in claudicants and its correlation with age, gender, localization of arterial obstruction, and symptomatic coronary disease. Patients (n = 170) with intermittent claudication were studied. The mean age was 65 years (33-89). Metabolic syndrome was diagnosed in 98 patients (57.6%). The mean age of patients with MetS was 63.5 years compared with 67.0 years for patients without MetS (P = .027). Considering patients aged >= 65 years, MetS was present in 46 (48.9%) individuals and in 52 (68.4%) patients younger than 65 years (P = .011). Metabolic syndrome must be actively searched for in claudicant patients.

Early Changes in Postprandial Gallbladder Emptying in Morbidly Obese Patients Undergoing Roux-en-Y Gastric Bypass: Correlation with the Occurrence of Biliary Sludge and Gallstones

Gallstones have been frequently diagnosed after Roux-en-Y gastric bypass (RYGBP). Gallbladder stasis associated with duodenal exclusion may play a role in their pathogenesis. Gallbladder emptying was studied before and on the 30th and 31st postoperative days (POD) after RYGBP in 20 morbidly obese patients. Gallbladder volume after fasting and every 15 min during a 2-h period following administration of a standard liquid meal was determined by sonography. On the 31st POD, the meal was administered through the gastrostomy in order to promote its transit through the duodenum. Fasting volume (FV), maximum ejection fraction (Max EF), and residual volume (RV) were determined. Biliary sludge and calculi were investigated after 1 and 6 months, respectively. FV was 39.4 +/- 20.2 ml, 50.1 +/- 22.7 ml, and 47.9 +/- 23.4 ml, respectively, for the preoperative and two postoperative assessments (P = 0.09). RV was 7.6 +/- 8.7 ml, 25.1 +/- 20.0 ml, and 24.6 +/- 20.9 ml; and Max EF was 80.5 +/- 20.9%, 54.3 +/- 21.4%, and 50.5 +/- 29.0%, respectively, for the pre-, postoral, and postgastrostomy infusion measurements. There was only a significant difference between the preoperative value and the two postoperative values (P < 0.001). Biliary sludge was detected in 65% of the patients and 46% of them subsequently developed gallstones. Gallbladder emptying became significantly compromised after RYGBP. This impairment was unrelated to duodenal exclusion but it was associated with biliary sludge and stone formation.

SINGLE MEASUREMENTS OF C-REACTIVE PROTEIN AND DISEASE ACTIVITY SCORES ARE NOT PREDICTORS OF CAROTID ATHEROSCLEROSIS IN RHEUMATOID ARTHRITIS PATIENTS

Background: Although inflammation has a defined role in the pathogenesis of atherosclerosis, the link between rheumatoid arthritis (RA) parameters of disease activity and atherosclerotic findings are not defined. Objective: To investigate the association between subclinical carotid atherosclerosis and clinical/laboratorial parameters of RA systemic inflammatory activity. Methods: Seventy-one RA patients were consecutively selected and compared to 53 healthy controls. Smoking, diabetes and hypertension were excluded, as well as the use of statins or fibrates. B-mode carotid ultrasound was performed in all subjects. CRP, ESR and fibrinogen were determined in both groups. Clinical assessment of RA activity included DAS 28 and SDAI. Correlation between plaques and intima-media thickness (IMT) of common carotid arteries and inflammatory parameters was evaluated. Results: Carotid plaques were more prevalent in RA patients than in controls (14.1% vs. 1.9 %, p=0.02) and marginally increased IMT was observed (0.72 +/- 0.17 vs. 0.67 +/- 0.15mm, p=0.07). RA patients with plaques had older age (p=0.001) and increased IMT (p<0.001), but low SDAI (p=0.025) compared to those without plaques. RA patients with plaques had also longer disease duration, although this difference did not reach statistical significance (p=0.06). No significant correlations were found between IMT and ESR (p=0.80), CRP (p=0.75), fibrinogen (p=0.94), HAQ (p=0.89) and DAS 28 (p=0.13). Conclusions: Carotid atherosclerosis is more frequently detected in RA but its prevalence was not correlated with isolated inflammatory markers measurement or noncumulative activity scores. These findings reinforce the need to evaluate subclinical atherosclerosis in RA patients, and to find predictors of atherosclerotic lesions.

Robust algorithms for solving stochastic partial differential equations

A robust semi-implicit central partial difference algorithm for the numerical solution of coupled stochastic parabolic partial differential equations (PDEs) is described. This can be used for calculating correlation functions of systems of interacting stochastic fields. Such field equations can arise in the description of Hamiltonian and open systems in the physics of nonlinear processes, and may include multiplicative noise sources. The algorithm can be used for studying the properties of nonlinear quantum or classical field theories. The general approach is outlined and applied to a specific example, namely the quantum statistical fluctuations of ultra-short optical pulses in chi((2)) parametric waveguides. This example uses a non-diagonal coherent state representation, and correctly predicts the sub-shot noise level spectral fluctuations observed in homodyne detection measurements. It is expected that the methods used wilt be applicable for higher-order correlation functions and other physical problems as well. A stochastic differencing technique for reducing sampling errors is also introduced. This involves solving nonlinear stochastic parabolic PDEs in combination with a reference process, which uses the Wigner representation in the example presented here. A computer implementation on MIMD parallel architectures is discussed. (C) 1997 Academic Press.

Correlation between CD34(+) and exercise capacity, functional class, quality of life and norepinephrine in heart failure patients

Background: A previous study associated CD34(+) levels with NYHA functional class in heart failure patients. The aim of this study was to correlate CD34(+) levels to exercise capacity, functional class, quality of life and norepinephrine in heart failure patients. Methods: Twenty three sedentary patients (52 +/- 7 years, 78% male) answered the Minnesota Living with Heart Failure Questionnaire and rested for 20 minutes before an investigator collect a blood sample. After this, patients performed a cardiopulmonary exercise test to determine the heart rate at anaerobic and ventilatory threshold and oxygen consumption at peak effort, at anaerobic and ventilatory threshold. One other blood sample was collected during the peak effort to investigate the norepinephrine and CD34(+) levels. Results: Rest percentage of CD34(+) did not show correlation with: left ventricle ejection fraction (r = 0.03, p = 0.888), peakVO(2) (r = 0.32, p = 0.13), VO(2) at anaerobic threshold (VO(2)AT) (r = 0.03, p = 0.86), VO(2) at ventilatory threshold (VO(2)VT) (r = 0.36, p = 0.08), NYHA functional class (r = -0.2, p = 0.35), quality of life (Minnesota) (r = -0.17, p = 0.42). CD34(+) did not show correlation, either, with: peak VO(2) (r = 0.38, p = 0.06), VO(2)AT (r = 0.09, p = 0.65), VO(2)VT (r = 0.43, p = 0.4), NYHA functional class (r = -0.13, p = 0.54), quality of life (r = 0.00, p = 0.99). Conclusions: CD34(+) levels did not correlate with exercise capacity, functional class, quality of life and norepinephrine. Percentage of CD34(+) levels did not increase during the cardiopulmonary exercise test in heart failure patients. (Cardiol J 2009; 16, 5: 426-431)

Analyzing the connectivity between regions of interest: An approach based on cluster Granger causality for NRI data analysis

The identification, modeling, and analysis of interactions between nodes of neural systems in the human brain have become the aim of interest of many studies in neuroscience. The complex neural network structure and its correlations with brain functions have played a role in all areas of neuroscience, including the comprehension of cognitive and emotional processing. Indeed, understanding how information is stored, retrieved, processed, and transmitted is one of the ultimate challenges in brain research. In this context, in functional neuroimaging, connectivity analysis is a major tool for the exploration and characterization of the information flow between specialized brain regions. In most functional magnetic resonance imaging (fMRI) studies, connectivity analysis is carried out by first selecting regions of interest (ROI) and then calculating an average BOLD time series (across the voxels in each cluster). Some studies have shown that the average may not be a good choice and have suggested, as an alternative, the use of principal component analysis (PCA) to extract the principal eigen-time series from the ROI(s). In this paper, we introduce a novel approach called cluster Granger analysis (CGA) to study connectivity between ROIs. The main aim of this method was to employ multiple eigen-time series in each ROI to avoid temporal information loss during identification of Granger causality. Such information loss is inherent in averaging (e.g., to yield a single ""representative"" time series per ROI). This, in turn, may lead to a lack of power in detecting connections. The proposed approach is based on multivariate statistical analysis and integrates PCA and partial canonical correlation in a framework of Granger causality for clusters (sets) of time series. We also describe an algorithm for statistical significance testing based on bootstrapping. By using Monte Carlo simulations, we show that the proposed approach outperforms conventional Granger causality analysis (i.e., using representative time series extracted by signal averaging or first principal components estimation from ROIs). The usefulness of the CGA approach in real fMRI data is illustrated in an experiment using human faces expressing emotions. With this data set, the proposed approach suggested the presence of significantly more connections between the ROIs than were detected using a single representative time series in each ROI. (c) 2010 Elsevier Inc. All rights reserved.

Renal Cell Carcinoma: T1 and T2 Signal Intensity Characteristics of Papillary and Clear Cell Types Correlated with Pathology

OBJECTIVE. The objective of our study was to describe the T1 and T2 signal intensity characteristics of papillary renal cell carcinoma (RCC) and clear cell RCC with pathologic correlation. MATERIALS AND METHODS. Of 539 RCCs, 49 tumors (21 papillary RCCs and 28 clear cell RCCs) in 45 patients were examined with MRI. Two radiologists retrospectively and independently assessed each tumor`s T1 and T2 signal intensity qualitatively and quantitatively (i.e., the signal intensity [SI] ratio [tumor SI/renal cortex SI]). Of the 49 tumors, 37 (76%) were assessed for pathology features including tumor architecture and the presence of hemosiderin, ferritin, necrosis, and fibrosis. MRI findings and pathology features were correlated. Statistical methods included summary statistics and Wilcoxon`s rank sum test for signal intensity, contingency tables for assessing reader agreement, concordance rate between the two readers with 95% CIs, and Fisher`s exact test for independence, all stratified by RCC type. RESULTS. Papillary RCCs and clear cell RCCs had a similar appearance and signal intensity ratio on T1-weighted images. On T2-weighted images, most papillary RCCs were hypointense (reader 1, 13/21; reader 2, 14/21), with an average mean signal intensity ratio for both readers of 0.67 +/- 0.2, and none was hyperintense, whereas most clear cell RCCs were hyperintense (reader 1, 21/28; reader 2, 17/28), with an average mean signal intensity ratio for both readers of 1.41 +/- 0.4 (p < 0.05). A tumor T2 signal intensity ratio of <= 0.66 had a specificity of 100% and sensitivity of 54% for papillary RCC. Most T2 hypointense tumors exhibited predominant papillary architecture; most T2 hyperintense tumors had a predominant nested architecture (p < 0.05). CONCLUSION. On T2-weighted images, most papillary RCCs are hypointense and clear cell RCCs, hyperintense. The T2 hypointense appearance of papillary RCCs correlated with a predominant papillary architecture at pathology.

Ligaments of the Posterior and Lateral Talar Processes: MRI and MR Arthrography of the Ankle and Posterior Subtalar Joint with Anatomic and Histologic Correlation

OBJECTIVE. MRI and combined ankle and posterior subtalar MR arthrography in cadavers were used to evaluate the ligaments of the posterior and lateral talar processes. Subsequent anatomic and histologic correlation was performed. MATERIALS AND METHODS. Ten cadaveric ankles were used. Routine radiography and MRI were initially performed. Ankle and posterior subtalar MR arthrography, followed by anatomic and histologic analysis, was then performed to allow better assessment of the ligaments of the lateral and posterior talar process. RESULTS. In all subjects, MR arthrography provided superior delineation of the articular and periarticular structures, as well as the ligaments. The lateral talocalcaneal and medial talocalcaneal ligaments were best seen in the axial and coronal planes, respectively. The axial plane was best for visualizing the fibulotalocalcaneal ligament, and the sagittal plane was best for evaluating the posterior talocalcaneal ligament. The anterior and posterior talofibular ligaments and the posterior tibiotalar ligament (superficial and deep portions) were best seen in the axial plane. Histologic analysis was correlated to anatomic sectioning and showed the attachment sites of these ligaments. CONCLUSION. Combined ankle and posterior subtalar MR arthrography enhances visualization of the ligaments attaching to the posterior and lateral talar processes, including the posterior, lateral, and medial talocalcaneal and fibulotalocalcaneal ligaments.

Validation of plasma clearance of (51)Cr-EDTA in adult renal transplant recipients: comparison with inulin renal clearance

Plasma clearance of (51)Cr-EDTA ((51)Cr-EDTA-Cl) is an alternative method to evaluate glomerular filtration rate (GFR). This study aimed to investigate the concordance between (51)Cr-EDTA-Cl and renal inulin clearance (In-Cl) in renal transplant recipients as well to determine the repeatability of (51)Cr-EDTA-Cl in kidney donors. Forty four kidney recipients and 22 kidney donors were enrolled. Simultaneous measurements of (51)Cr-EDTA-Cl and In-Cl were performed. A single dose of 3.7MBq of (51)Cr-EDTA was injected and the plasma disappearance curve was created by taking blood samples at 2, 4, 6 and 8 h after injection. Bland and Altman statistical approach was used to quantify the agreement between In-Cl and (51)Cr-EDTA-Cl and to determine the better concordance between all possibilities of measure for the (51)Cr-EDTA-Cl. The mean of In-Cl was 44.5 +/- 17.9 ml/min/1.73 m(2). There was a positive correlation between In-Cl and all possible measurements of (51)Cr-EDTA-Cl. (51)Cr-EDTA-Cl with two samples taken at 4 and 8 h or at 4 and 6 h presenting the narrow limits of agreement and a difference (bias) of 2.8 and 2.7 ml/min, respectively. Two plasma sampling for (51)Cr-EDTA-Cl was a reliable method to measure GFR compared with In-Cl and comprises a suitable method to be used in kidney transplanted patients.