168 research outputs found
Electromyogram-Biofeedback in Patients with Fibromyalgia A Randomized Controlled Trial
Electromyogram-Biofeedback in Patients with Fibromyalgia: A Randomized Controlled Trial
Objective: To evaluate the effectiveness of EMG-biofeedback in patients with Fibromyalgia. Design: The study design was a randomized controlled pilot trial with blinded assessors and three points of assessment: before intervention (baseline, T0), at the end of treatment (T1) and a 3-months follow-up (T2).
Setting: Outpatient clinic.
Patients: Patients from the waiting list of the Fibromyalgia day hospital program fulfilling the inclusion criteria.
Intervention: During eight weeks, 14 sessions of EMG-biofeedback training versus usual care only.
Outcome Measures and Analysis: For primary outcome, the disease specific health status was followed using the Fibromyalgia Impact Questionnaire (FIQ). Secondary outcome measures comprise assessment of pain (Tender Point Score), tenderness (Tender Point Count = number of Tender Points, Pain Pressure Threshold), generic health status (SF-36), Patients’ Global Clinical Impression of Change and psychic impact (Beck depression Inventory, Symptom Checklist 90-Revised). Effects were analyzed with sensitivity statistics (effect size, ES), parametric and nonparametric tests.
Results: The data of 36 patients with complete follow-up data could be analyzed. EMG-EMG-biofeedback did not improve health status of patients with Fibromyalgia (FIQ, T1: ES = 0.02, p = 0.95, T2: ES = 0.26, p = 0.43). Also, the secondary outcome measures, with the exception of the pressure pain threshold (T1: ES = 0.26, p = 0.014), showed no superiority of EMG-biofeedback in addition to usual care compared to usual care alone.
Conclusion: In the treatment of patients with Fibromyalgia, EMG-biofeedback training in addition to usual medical care is not superior to usual medical care alone
Diagnostic accuracy and added value of dual-energy subtraction radiography compared to standard conventional radiography using computed tomography as standard of reference
PURPOSE: To retrospectively evaluate diagnostic performance of dual-energy subtraction radiography (DESR) for interpretation of chest radiographs compared to conventional radiography (CR) using computed tomography (CT) as standard of reference.
MATERIAL AND METHODS: A total of 199 patients (75 female, median age 67) were included in this institutional review board (IRB)-approved clinical trial. All patients were scanned in posteroanterior and lateral direction with dual-shot DE-technique. Chest CT was performed within ±72 hours. The system provides three types of images: bone weighted-image, soft tissue weighted-image, herein termed as DESR-images, and a standard image, termed CR-image (marked as CR-image). Images were evaluated by two radiologists for presence of inserted life support lines, pneumothorax, pleural effusion, infectious consolidation, interstitial lung changes, tumor, skeletal alterations, soft tissue alterations, aortic or tracheal calcification and pleural thickening. Inter-observer agreement between readers and diagnostic performance were calculated. McNemar's test was used to test for significant differences.
RESULTS: Mean inter-observer agreement throughout the investigated parameters was higher in DESR images compared to CR-images (kDESR = 0.935 vs. kCR = 0.858). DESR images provided significantly increased sensitivity compared to CR-images for the detection of infectious consolidations (42% vs. 62%), tumor (46% vs. 57%), interstitial lung changes (69% vs. 87%) and aortic or tracheal calcification (25 vs. 73%) (p<0.05). There were no significant differences in sensitivity for the detection of inserted life support lines, pneumothorax, pleural effusion, skeletal alterations, soft tissue alterations or pleural thickening (p>0.05).
CONCLUSION: DESR increases significantly the sensibility without affecting the specificity evaluating chest radiographs, with emphasis on the detection of interstitial lung diseases
A new abundance scale for the globular cluster 47 Tuc
We present chemical abundances for O, Na, Mg, Al, Si, Ca, Ti and Fe in eight
red giants and one turnoff star in the metal rich globular cluster 47 Tuc,
based on spectroscopy with the MIKE high resolution spectrograph on the
Magellan 6.5-m Clay telescope. A robust line by line differential abundance
analysis technique, relative to the K-giant Arcturus, was used to reduce
systematic errors from atmospheric and atomic parameters. Our derived mean LTE
[Fe/H] of -0.76 +- 0.01 +- 0.04 dex (random and systematic error, respectively)
is more metal poor by about 0.1 dex than recent literature results. The
chemical element ratios in this nearby globular cluster most closely resemble
those of the Galactic bulge, although there is a non-negligible overlap with
the composition of thick-disk stars. We find that the [Al/Fe] and [Na/Fe]
ratios coincide with the upper boundary of the trends seen in the bulge and
thick disk. There is only a small intrinsic scatter in the majority of the
abundance ratios, indicating that 47 Tuc is mostly a rather chemically
homogeneous system.Comment: Now with correct Figure 6; no other changes; 22 pages, 8 figures,
accepted for publication in the A
Maximum Diameter Measurements of Aortic Aneurysms on Axial CT Images After Endovascular Aneurysm Repair: Sufficient for Follow-up?
Purpose: To assess the accuracy of maximum diameter measurements of aortic aneurysms after endovascular aneurysm repair (EVAR) on axial computed tomographic (CT) images in comparison to maximum diameter measurements perpendicular to the intravascular centerline for follow-up by using three-dimensional (3D) volume measurements as the reference standard. Materials and Methods: Forty-nine consecutive patients (73±7.5years, range 51-88years), who underwent EVAR of an infrarenal aortic aneurysm were retrospectively included. Two blinded readers twice independently measured the maximum aneurysm diameter on axial CT images performed at discharge, and at 1 and 2years after intervention. The maximum diameter perpendicular to the centerline was automatically measured. Volumes of the aortic aneurysms were calculated by dedicated semiautomated 3D segmentation software (3surgery, 3mensio, the Netherlands). Changes in diameter of 0.5cm and in volume of 10% were considered clinically significant. Intra- and interobserver agreements were calculated by intraclass correlations (ICC) in a random effects analysis of variance. The two unidimensional measurement methods were correlated to the reference standard. Results: Intra- and interobserver agreements for maximum aneurysm diameter measurements were excellent (ICC=0.98 and ICC=0.96, respectively). There was an excellent correlation between maximum aneurysm diameters measured on axial CT images and 3D volume measurements (r=0.93, P<0.001) as well as between maximum diameter measurements perpendicular to the centerline and 3D volume measurements (r=0.93, P<0.001). Conclusion: Measurements of maximum aneurysm diameters on axial CT images are an accurate, reliable, and robust method for follow-up after EVAR and can be used in daily routin
The Chemical Compositions of Non-Variable Red and Blue Field Horizontal Branch Stars
We present a new detailed abundance study of field red horizontal branch
(RHB) and blue horizontal branch (BHB) non-variable stars. High resolution and
high S/N echelle spectra of 11 RHB and 12 BHB were obtained with the McDonald
2.7 m telescope, and the RHB sample was augmented by reanalysis of spectra of
25 stars from a recent survey. We derived stellar atmospheric parameters based
on spectroscopic constraints, and computed relative abundance ratios for 24
species of 19 elements. The species include Si II and Ca II, which have not
been previously studied in RHB and BHB (Teff < 9000 K) stars. The abundance
ratios are generally consistent with those of similar-metallicity field stars
in different evolutionary stages. We estimated the masses of the RHB and BHB
stars by comparing their Teff--log g positions with HB model evolutionary
tracks. The mass distribution suggests that our program stars possess masses of
~0.5 Msun. Finally, we compared the temperature distributions of field RHB and
BHB stars with field RR Lyraes in the metallicity range -0.8 >~ [Fe/H] >~ -2.5.
This yielded effective temperatures estimates of 5900K and 7400 K for the red
and blue edges of the RR Lyrae instability strip.Comment: Accepted to A
Chromium: NLTE abundances in metal-poor stars and nucleosynthesis in the Galaxy
Aims. We investigate statistical equilibrium of Cr in the atmospheres of
late-type stars to show whether the systematic abundance discrepancy between Cr
I and Cr II lines, as often encountered in the literature, is due to deviations
from LTE. Furthermore, we attempt to interpret the NLTE trend of [Cr/Fe] with
[Fe/H] using chemical evolution models for the solar neighborhood. Methods.
NLTE calculations are performed for the model of Cr atom, comprising 340 levels
and 6806 transitions in total. We make use of the quantum-mechanical
photoionization cross-sections of Nahar (2009) and investigate sensitivity of
the model to uncertain cross-sections for H I collisions. NLTE line formation
is performed for the MAFAGS-ODF model atmospheres of the Sun and 10 metal-poor
stars with -3.2 < [Fe/H] < -0.5, and abundances of Cr are derived by comparison
of the synthetic and observed flux spectra. Results. We achieve good ionization
equilibrium of Cr for the models with different stellar parameters, if
inelastic collisions with H I atoms are neglected. The solar NLTE abundance
based on Cr I lines is 5.74 dex with {\sigma} = 0.05 dex; it is \sim 0.1 higher
than the LTE abundance. For the metal-poor stars, the NLTE abundance
corrections to Cr I lines range from +0.3 to +0.5 dex. The resulting [Cr/Fe]
ratio is roughly solar for the range of metallicities analyzed here, which is
consistent with current views on production of these iron peak elements in
supernovae. Conclusions. The tendency of Cr to become deficient with respect to
Fe in metal-poor stars is an artifact due to neglect of NLTE effects in the
line formation of Cr I, and it has no relation to peculiar physical conditions
in the Galactic ISM or deficiencies of nucleosynthesis theory.Comment: 14 pages, 13 figures, to be published in A&
Low-dose CT of the lung: potential value of iterative reconstructions
Objectives: To prospectively assess the impact of sinogram-affirmed iterative reconstruction (SAFIRE) on image quality of nonenhanced low-dose lung CT as compared to filtered back projection (FBP). Methods: Nonenhanced low-dose chest CT (tube current-time product: 30mAs) was performed on 30 patients at 100kVp and on 30 patients at 80kVp. Images were reconstructed with FBP and SAFIRE. Two blinded, independent readers measured image noise; two readers assessed image quality of normal anatomic lung structures on a five-point scale. Radiation dose parameters were recorded. Results: Image noise in datasets reconstructed with FBP (57.4 ± 15.9) was significantly higher than with SAFIRE (31.7 ± 9.8, P < 0.001). Image quality was significantly superior with SAFIRE than with FBP (P < 0.01), without significant difference between FBP at 100kVp and SAFIRE at 80kVp (P = 0.68). Diagnostic image quality was present with FBP in 96% of images at 100kVp and 88% at 80kVp, and with SAFIRE in 100% at 100kVp and 98% at 80kVp. There were significantly more datasets with diagnostic image quality with SAFIRE than with FBP (P < 0.01). Mean CTDIvol and effective doses were 1.5 ± 0.7mGy·cm and 0.7 ± 0.2mSv at 100kVp, and 1.4 ± 2.8mGy·cm and 0.5 ± 0.2mSv at 80kVp (P < 0.001, both). Conclusions: Use of SAFIRE in low-dose lung CT reduces noise, improves image quality, and renders more studies diagnostic as compared to FBP. Key Points : • Low-dose computed tomography is an important thoracic investigation tool. • Radiation dose can be less than 1mSv with iterative reconstructions. • Iterative reconstructions render more low-dose lung CTs diagnostic compared to conventional reconstruction
Maximum diameter measurements of aortic aneurysms on axial CT images after endovascular aneurysm repair: sufficient for follow-up?
PURPOSE: To assess the accuracy of maximum diameter measurements of aortic aneurysms after endovascular aneurysm repair (EVAR) on axial computed tomographic (CT) images in comparison to maximum diameter measurements perpendicular to the intravascular centerline for follow-up by using three-dimensional (3D) volume measurements as the reference standard. MATERIALS AND METHODS: Forty-nine consecutive patients (73 ± 7.5 years, range 51-88 years), who underwent EVAR of an infrarenal aortic aneurysm were retrospectively included. Two blinded readers twice independently measured the maximum aneurysm diameter on axial CT images performed at discharge, and at 1 and 2 years after intervention. The maximum diameter perpendicular to the centerline was automatically measured. Volumes of the aortic aneurysms were calculated by dedicated semiautomated 3D segmentation software (3surgery, 3mensio, the Netherlands). Changes in diameter of 0.5 cm and in volume of 10% were considered clinically significant. Intra- and interobserver agreements were calculated by intraclass correlations (ICC) in a random effects analysis of variance. The two unidimensional measurement methods were correlated to the reference standard. RESULTS: Intra- and interobserver agreements for maximum aneurysm diameter measurements were excellent (ICC = 0.98 and ICC = 0.96, respectively). There was an excellent correlation between maximum aneurysm diameters measured on axial CT images and 3D volume measurements (r = 0.93, P < 0.001) as well as between maximum diameter measurements perpendicular to the centerline and 3D volume measurements (r = 0.93, P < 0.001). CONCLUSION: Measurements of maximum aneurysm diameters on axial CT images are an accurate, reliable, and robust method for follow-up after EVAR and can be used in daily routine
Image fusion of coronary CT angiography and cardiac perfusion MRI: a pilot study
Objective: To develop a tool for the image fusion of computed tomography coronary angiography (CTCA) and cardiac magnetic resonance imaging (CMR). Methods: Surface representations and volume-rendered images from fused CTCA/CMR data of five patients with significant coronary artery disease (CAD) on CTCA and perfusion deficits on CMR were generated using a newly developed software prototype. The spatial relationship of significant coronary artery stenosis at CTCA and myocardial defects at CMR was evaluated. Results: Registration of CTCA and CMR images was possible in all patients. The comprehensive three-dimensional visualisation of fused CTCA and CMR data accurately demonstrated the relationship between coronary artery stenoses and myocardial defects in all patients. Conclusion: The introduced tool enables image fusion of CTCA and CMR data sets and allows for correct superposition of the coronary arteries derived from CTCA onto the corresponding myocardial segments derived from CMR. The method facilitates the comprehensive assessment of the functionally relevant CAD by the exact allocation of culprit coronary stenoses to corresponding myocardial defects at a low radiation dos
High-pitch dual-source CT coronary angiography: systolic data acquisition at high heart rates
Objective: To assess the effect of systolic data acquisition for electrocardiography (ECG)-triggered high-pitch computed tomography (CT) on motion artefacts of coronary arteries in patients with high heart rates (HRs). Methods: Eighty consecutive patients (15 women, age 67 ± 14years) with HR ≥70bpm underwent CT angiography of the thoracic aorta (CTA) on 128-slice dual-source CT in ECG-triggered high-pitch acquisition mode (pitch = 3.2) set at 60% (group A, n = 40) or 30% (group B, n = 40) of the RR interval. Two blinded readers graded coronary artery image quality on a three-point scale. Radiation doses were calculated. Results: Inter-observer agreement in grading image quality of the 1,154 coronary segments was good (κ = 0.62). HRs were similar in groups A and B (85 ± 13bpm vs 85 ± 14bpm, p not significant). Significantly fewer coronary segments with non-diagnostic image quality occurred (i.e. score 3) in group B than in group A [2.8% (16/579) vs 8.3% (48/575), p < 0.001]. Seventeen patients (42.5%) of group A and 12 patients (30.0%) of group B had at least one non-diagnostic segment. Effective radiation doses were 2.3 ± 0.3mSv for chest CTA. Conclusion: A systolic acquisition window for high-pitch dual-source CTA in patients with high HRs (≥70bpm) significantly improves coronary artery image quality at a low radiation dos
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