Inter- and intra-rater-reliability of a clinical framework for spine-related neck-arm pain.

OBJECTIVE: A mechanism-based clinical framework for spine-related pain differentiates (i) somatic referred pain, ii) heightened nerve mechanosensitivity, iii) radicular pain, iv) radiculopathy and mixed-pain. This study aimed to determine the reliability of proposed framework. METHOD: Fifty-one people with unilateral spine-related neck-arm pain were assessed and categorized by examiner-1. The classifications were compared to those made by two other examiners, based on written documentation of examiner-1. Cohens kappa was calculated between examiner-pairs; Fleiss Kappa among all examiners to assess agreement in classifying subgroups and entire framework. RESULT: Inter-rater-reliability showed moderate to almost perfect reliability (somatic: no variation, mechanosensitivity: 0.96 (95% CI 0.87-1.0) to 1.0 (95% CI: 1.0-1.0), radicular pain: 0.46 (95% CI: 0.19-0.69) to 0.62 (95% CI: 0.42-0.81), radiculopathy: 0.65 (95% CI: 0.43-0.84) to 0.80 (95% CI: 0.63-0.96) mixed-pain: 0.54 (95% CI: 0.21-0.81) to 0.75 (95% CI: 0.48-0.94). There was almost perfect to moderate reliability among all examiners (somatic: no variation, mechanosensitivity: 0.97 (95% CI: 0.82-1.0), radicular pain: 0.56 (95% CI: 0.40-0.71), radiculopathy: 0.74 (95% CI: 0.58-0.90), mixed-pain: 0.63 (95% CI: 0.47-0.79), entire framework: 0.64 (95% CI: 0.57-0.71)). Intra-rater-reliability showed substantial to almost perfect reliability (somatic: no variation, mechanosensitivity: 0.96 (95% CI: 0.87-1.0), radicular pain: 0.76 (95% CI: 0.57-0.92), radiculopathy: 0.84 (95% CI: 0.67-0.96), mixed-pain: 0.83 (95% CI: 0.60-1.0), entire framework: 0.80 (95% CI: 0.61-0.92). CONCLUSION: Moderate to almost perfect reliability in subgrouping people with spine-related neck-arm pain and substantial reliability for entire framework support this classification's reliability.

Non-surgical external jugular vein catheterization using an ear vein access in piglets.

The objective of this study was to investigate the feasibility of external jugular vein catheterization through an ear vein in piglets. Forty-six sevoflurane-midazolam anaesthetized piglets were included. External jugular vein catheterization was conducted through the ear vein using the Seldinger technique. Part 1 (n = 27): optimal puncture site was based on the deltoid tuberosity as a landmark to reach the external jugular vein. The final position of the catheter was verified in 25 piglets using computer tomography. Catheterization time was recorded and patency of the catheter assessed by repeated blood sampling for up to 4 h. Part 2 (n = 19): ear vein catheterization was without taking into account any landmarks. Functionality for blood sampling was evaluated as described in part 1. Catheter advancement was possible in 25/27 and 18/19 piglets in parts 1 and 2, respectively. Median (range) time required for successful catheterization was 1.95 (1-10) min (n = 38). The deltoid tuberosity was a good landmark to reach the external jugular vein. But blood sampling was also possible through catheters ending slightly cranial to the external jugular vein. Despite successful catheter advancement, blood sampling was not possible from one catheter in each part of the study (total: two piglets). One of these catheters presented luminal damage, while the other one presented as normal after being removed from the animal. Summarizing, central vein catheterization through the ear vein was feasible in 93.5% and repeated blood sampling was possible in 89.1% of the piglets (n = 46).

Noise-optimized virtual monoenergetic reconstructions of dual-energy CT angiographies improve assessability of the lower leg arterial segments in peripheral arterial occlusive disease.

INTRODUCTION: The aim of this study was to evaluate the influence of a noise optimized virtual monoenergetic reconstruction algorithm (VMI+) on the image quality and assessability of dual energy (DE) computed tomography angiography (CTA) of the lower extremity runoff. METHODS: A total of 118 lower extremity runoff CTA performed on a 3rd generation DE-CT scanner in 109 patients (54 females; 75.6 ± 9.5 years) were included in this retrospective study. Axial image stacks were reconstructed with a standard 120 kV setting and VMI+ of different keV levels. Objective image quality criteria (contrast attenuation, signal-to-noise [SNR] and contrast-to-noise ratio [CNR]) were measured. Two radiologists evaluated subjective image quality regarding intraluminal attenuation and image noise using a 5-point Likert scale. Diagnostic accuracy for significant stenosis (>75%) and vessel occlusion was assessed for 120 kV and 50 keV VMI+ images rated by two radiologists. In all patients, a digital subtraction angiography (DSA) rated by on board-certified radiologist served as the standard of reference. RESULTS: Intraluminal attenuation was highest in 40/50 keV VMI+ while SNR were similar to 120 kV images. In subjective assessment, intraluminal contrast of 50 keV images was deemed superior compared to 120 kV despite higher image noise. Sensitivity, specificity, and accuracy for detection of a vessel occlusion were similar in 50 keV VMI+ compared to 120 kV (70%/92%/84%; 70%/91%/83%; p < 0.001) but 13 of 118 (11%) lower leg runoffs were only assessable with 50 keV VMI+. CONCLUSION: VMI+ reconstructions improve assessability of DE-CTA by increased luminal attenuation with consistent image noise, also allowing the evaluation of lower leg arterial segments inassessable with standard reconstructions. IMPLICATIONS FOR PRACTICE: Providing higher intraluminal attenuation and similar image noise compared with conventional reconstructions, 50 keV VMI+ may be appropriate for routine evaluation of DE-CTA.

Near-Monochromatic Tuneable Cryogenic Niobium Electron Field Emitter.

Creating, manipulating, and detecting coherent electrons is at the heart of future quantum microscopy and spectroscopy technologies. Leveraging and specifically altering the quantum features of an electron beam source at low temperatures can enhance its emission properties. Here, we describe electron field emission from a monocrystalline, superconducting niobium nanotip at a temperature of 5.9 K. The emitted electron energy spectrum reveals an ultranarrow distribution down to 16 meV due to tunable resonant tunneling field emission via localized band states at a nanoprotrusion's apex and a cutoff at the sharp low-temperature Fermi edge. This is an order of magnitude lower than for conventional field emission electron sources. The self-focusing geometry of the tip leads to emission in an angle of 3.7°, a reduced brightness of 3.8×10^{8} A/(m^{2} sr V), and a stability of hours at 4.1 nA beam current and 69 meV energy width. This source will decrease the impact of lens aberration and enable new modes in low-energy electron microscopy, electron energy loss spectroscopy, and high-resolution vibrational spectroscopy.

T2-weighted MRI defines critical compression in the distal carpal tunnel that is relieved after decompressive surgery.

INTRODUCTION: Despite carpal tunnel syndrome (CTS) being the most common entrapment neuropathy, its pathophysiology remains debated. Sub-synovial connective tissues (SSCT) within the carpal tunnel are thought to play a role but are poorly characterised. MRI analysis offers potentially novel insights into SSCT characteristics. METHODS: A pilot study of T2-weighted MRI was performed in healthy controls (n = 7), and in CTS patients (n = 16) pre- and 6 months post-surgical decompression. Image analysis was performed to quantify SSCT cross-sectional area, SSCT signal intensity ratio, and wrist index (depth/width) at distal, middle, and proximal wrist landmarks. RESULTS: Median SSCT signal intensity was lower in the distal carpal tunnel of CTS patients pre-operatively (0.96) compared to controls (1.13; P = 0.008) and normalised post-operatively (1.13, P = 0.001). Median wrist index was also lower in CTS patients pre-operatively (0.60) than in controls (0.67, P = 0.022), and again normalised post-operatively (0.74, P = 0.001). This was attributed to changes in carpal depth in the anteroposterior axis with decompression surgery. CONCLUSION: This pilot study successfully demonstrated MRI assessment of SSCT in patients with CTS. The decreased SSCT signal intensities suggest predominant changes at the distal tunnel, potentially indicating reduced SSCT perfusion pre-surgery which normalised post-surgery. Our preliminary findings merit further investigation in a larger cohort.

Replication of epidemiological associations of carpal tunnel syndrome in a UK population-based cohort of over 400,000 people.

INTRODUCTION: Several phenotypic factors are associated in the literature with an increased risk of carpal tunnel syndrome (CTS). Along with female sex and older age, certain systemic diseases show an association with CTS, with varying degrees of evidence. METHODS: This study was performed using the UK Biobank resource - a cohort study of over 500,000 participants who have allowed linkage of phenotypic data with their medical records. We calculated the prevalence of CTS and a sex-specific prevalence ratio and compared the body mass index (BMI) between cases and controls. We performed a series of nested case-control studies to compute odds ratios for the association between CTS and three systemic diseases. RESULTS: There were 12,312 CTS cases within the curated UK Biobank dataset of 401,656 (3.1% prevalence), and the female:male ratio was 1.95:1. CTS cases had, on average, a BMI > 2.0 kg/m2 greater than controls. Odds ratios for the association with CTS for three systemic diseases were 2.31 (95% CI 2.17-2.46) for diabetes, 2.70 (95% CI 2.44-2.99) for rheumatoid arthritis, and 1.47 (95% CI 1.38-1.57) for hypothyroidism. Adjusted for BMI, these odds ratios fell to 1.75 (95% CI 1.65-1.86), 2.43 (95% CI 2.20-2.69), and 1.35 (95% CI 1.26-1.43), respectively. DISCUSSION: We harnessed the size and power of UK Biobank to provide robust replication of evidence for the associations between CTS and female sex, raised BMI, and three systemic diseases, which are only mediated in part by raised BMI.

Heat flows in rock cracks naturally optimize salt compositions for ribozymes.

Catalytic nucleic acids, such as ribozymes, are central to a variety of origin-of-life scenarios. Typically, they require elevated magnesium concentrations for folding and activity, but their function can be inhibited by high concentrations of monovalent salts. Here we show that geologically plausible high-sodium, low-magnesium solutions derived from leaching basalt (rock and remelted glass) inhibit ribozyme catalysis, but that this activity can be rescued by selective magnesium up-concentration by heat flow across rock fissures. In contrast to up-concentration by dehydration or freezing, this system is so far from equilibrium that it can actively alter the Mg:Na salt ratio to an extent that enables key ribozyme activities, such as self-replication and RNA extension, in otherwise challenging solution conditions. The principle demonstrated here is applicable to a broad range of salt concentrations and compositions, and, as such, highly relevant to various origin-of-life scenarios.

Sensorimotor and body perception assessments of nonspecific chronic low back pain: a cross-sectional study.

BACKGROUND: Low back pain (LBP) is one of the most common musculoskeletal disorders, causing significant personal and social burden. Current research is focused on the processes of the central nervous system (particularly the sensorimotor system) and body perception, with a view to developing new and more efficient ways to treat chronic low back pain (CLBP). Several clinical tests have been suggested that might have the ability to detect alterations in the sensorimotor system. These include back-photo assessment (BPA), two-point discrimination (TPD), and the movement control tests (MCT). The aim of this study was to determine whether the simple clinical tests of BPA, TPD or MCT are able to discriminate between nonspecific CLBP subjects with altered body perception and healthy controls. METHODS: A cross-sectional study was conducted. At one point in time, 30 subjects with CLBP and 30 healthy controls were investigated through using BPA, TPD and MCT on the lower back. Correlations among the main covariates and odds ratios for group differences were calculated. RESULTS: MCT showed an odds ratio for the presence of CLBP of 1.92, with a statistically significant p-value (0.049) and 95%CI. The TPD and BPA tests were unable to determine significant differences between the groups. CONCLUSIONS: Of the three tests investigated, MCT was found to be the only suitable assessment to discriminate between nonspecific CLBP subjects and healthy controls. The MCT can be recommended as a simple clinical tool to detect alterations in the sensorimotor system of nonspecific CLBP subjects. This could facilitate the development of tailored management strategies for this challenging LBP subgroup. However, further research is necessary to elucidate the potential of all the tests to detect alterations in the sensorimotor system of CLBP subjects. TRIAL REGISTRATION: No trial registration was needed as the study contains no intervention. The study was approved by the Swiss Ethics Commission of Northwest and Central Switzerland (EKNZ) reference number 2015-243.

Effect of long term CPAP therapy on cardiac parameters assessed with cardiac MRI.

The obstructive sleep apnoea syndrome (OSAS) is a disorder with a high prevalence and is associated with an elevated cardiovascular risk and increased morbidity and mortality. For longitudinal studies and functional analysis cardiac MRI is regarded as the gold standard. Aim of this study was to evaluate the long-term effect of continuous positive airway pressure (CPAP) therapy on cardiac functional parameters with cardiac Magnetic Resonance Imaging (cMRI). 54 patients with OSAS (mean apnea hypopnea index-AHI: 31) were prospectively enrolled in this study and cMRI was performed before and after 7 months of CPAP therapy. Data were acquired on a 1.5 T MRI and right and left ventricular cardiac function were analysed. CPAP treatment was considered compliant when used ≥ 4 h per night. 24-h blood pressure was measured at baseline and follow up. 33 patients could be assigned to the compliance group. Left ventricular stroke volume (LV SV) and right ventricular ejection fraction (RV EF) improved significantly with CPAP therapy (LV SV from 93 ± 19 to 99 ± 20 ml, p = 0.02; RV EF from 50 ± 6 to 52 ± 6%, p = 0.04). All other cardiac parameters did not change significantly while mean systolic and diastolic blood pressure improved significantly (p < 0.01). 21 patients were assigned to the non-compliance group and were considered as a control group. There were no relevant differences in cardiac parameters between baseline and follow up examination in these patients. CPAP therapy seems to improve LV SV, RV EF, systolic and diastolic blood pressure in OSAS patients, but reproducibility of our results need to be confirmed in a larger patient population.

Magnetic Hamiltonian parameter estimation using deep learning techniques.

Understanding spin textures in magnetic systems is extremely important to the spintronics and it is vital to extrapolate the magnetic Hamiltonian parameters through the experimentally determined spin. It can provide a better complementary link between theories and experimental results. We demonstrate deep learning can quantify the magnetic Hamiltonian from magnetic domain images. To train the deep neural network, we generated domain configurations with Monte Carlo method. The errors from the estimations was analyzed with statistical methods and confirmed the network was successfully trained to relate the Hamiltonian parameters with magnetic structure characteristics. The network was applied to estimate experimentally observed domain images. The results are consistent with the reported results, which verifies the effectiveness of our methods. On the basis of our study, we anticipate that the deep learning techniques make a bridge to connect the experimental and theoretical approaches not only in magnetism but also throughout any scientific research.

Yoga improves balance, mobility, and perceived occupational performance in adults with chronic brain injury: A preliminary investigation.

BACKGROUND AND PURPOSE: This was a preliminary investigation to investigate potential benefits of group yoga, as past work has indicated that one-on-one yoga can improve functional deficits in adults with brain injury. MATERIALS AND METHODS: Participants served as their own controls. Nine participants with chronic brain injury were recruited, and seven (four female) completed the study. Performance measures of balance and mobility and self-reported measures of balance confidence, pain, and occupational performance and satisfaction were used. Data were collected 3 times: baseline (study onset), pre-yoga (after an 8-week no-contact period), and post-yoga (after 8 weeks of yoga). Group yoga was led by a yoga instructor/occupational therapist, and sessions lasted 1 h and occurred twice a week. RESULTS: No participants withdrew due to adverse effects from yoga. There were no significant changes between baseline and pre-yoga. Significant improvement was observed post-yoga in balance (p = 0.05), mobility (p = 0.03), and self-reported occupational performance (p = 0.04). CONCLUSION: We observed significant improvements in balance, mobility, and self-reported occupational performance in adults with chronic brain injury.

Consensus in determining the resectability of locally progressed pancreatic ductal adenocarcinoma - results of the Conko-007 multicenter trial.

BACKGROUND: One critical step in the therapy of patients with localized pancreatic cancer is the determination of local resectability. The decision between primary surgery versus upfront local or systemic cancer therapy seems especially to differ between pancreatic cancer centers. In our cohort study, we analyzed the independent judgement of resectability of five experienced high volume pancreatic surgeons in 200 consecutive patients with borderline resectable or locally advanced pancreatic cancer. METHODS: Pretherapeutic CT or MRI scans of 200 consecutive patients with borderline resectable or locally advanced pancreatic cancer were evaluated by 5 independent pancreatic surgeons. Resectability and the degree of abutment of the tumor to the venous and arterial structures adjacent to the pancreas were reported. Interrater reliability and dispersion indices were compared. RESULTS: One hundred ninety-four CT scans and 6 MRI scans were evaluated and all parameters were evaluated by all surgeons in 133 (66.5%) cases. Low agreement was observed for tumor infiltration of venous structures (κ = 0.265 and κ = 0.285) while good agreement was achieved for the abutment of the tumor to arterial structures (interrater reliability celiac trunk κ = 0.708 P < 0.001). In patients with vascular tumor contact indicating locally advanced disease, surgeons highly agreed on unresectability, but in patients with vascular tumor abutment consistent with borderline resectable disease, the judgement of resectability was less uniform (dispersion index locally advanced vs. borderline resectable p < 0.05). CONCLUSION: Excellent agreement between surgeons exists in determining the presence of arterial abutment and locally advanced pancreatic cancer. The determination of resectability in borderline resectable patients is influenced by additional subjective factors. TRIAL REGISTRATION: EudraCT:2009-014476-21 (2013-02-22) and NCT01827553 (2013-04-09).

Bevacizumab plus hypofractionated radiotherapy versus radiotherapy alone in elderly patients with glioblastoma: the randomized, open-label, phase II ARTE trial.

Background: The addition of bevacizumab to temozolomide-based chemoradiotherapy (TMZ/RT â†’ TMZ) did not prolong overall survival (OS) in patients with newly diagnosed glioblastoma in phase III trials. Elderly and frail patients are underrepresented in clinical trials, but early reports suggested preferential benefit in this population. Patients and methods: ARTE was a 2 : 1 randomized, multi-center, open-label, non-comparative phase II trial of hypofractionated RT (40 Gy in 15 fractions) with bevacizumab (10 mg/kg×14 days) (arm A, N = 50) or without bevacizumab (arm B, N = 25) in patients with newly diagnosed glioblastoma aged ≥65 years. The primary objective was to obtain evidence for prolongation of median OS by the addition of bevacizumab to RT. Response was assessed by RANO criteria. Quality of life (QoL) was monitored by the EORTC QLQ-C30/BN20 modules. Exploratory studies included molecular subtyping by 450k whole methylome and gene expression analyses. Results: Median PFS was longer in arm A than in arm B (7.6 and 4.8 months, P = 0.003), but OS was similar (12.1 and 12.2 months, P = 0.77). Clinical deterioration was delayed and more patients came off steroids in arm A. Prolonged PFS in arm A was confined to tumors with the receptor tyrosine kinase (RTK) I methylation subtype (HR 0.25, P = 0.014) and proneural gene expression (HR 0.29, P = 0.025). In a Cox model of OS controlling for established prognostic factors, associations with more favorable outcome were identified for age <70 years (HR 0.52, P = 0.018) and Karnofsky performance score 90%-100% (HR 0.51, P = 0.026). Including molecular subtypes into that model identified an association of the RTK II gene methylation subtype with inferior OS (HR 1.73, P = 0.076). Conclusion: Efficacy outcomes and exploratory analyses of ARTE do not support the hypothesis that the addition of bevacizumab to RT generally prolongs survival in elderly glioblastoma patients. Molecular biomarkers may identify patients with preferential benefit from bevacizumab. Clinical trial registration number: NCT01443676.

A novel optically transparent RF shielding for fully integrated PET/MRI systems.

Preclinical imaging benefits from simultaneous acquisition of high-resolution anatomical and molecular data. Additionally, PET/MRI systems can provide functional PET and functional MRI data. To optimize PET sensitivity, we propose a system design that fully integrates the MRI coil into the PET system. This allows positioning the scintillators near the object but requires an optimized design of the MRI coil and PET detector. It further requires a new approach in realizing the radiofrequency (RF) shielding. Thus, we propose the use of an optically transparent RF shielding material between the PET scintillator and the light sensor, suppressing the interference between both systems. We evaluated two conductive foils (ITO, 9900) and a wire mesh. The PET performance was tested on a dual-layer scintillator consisting of 12 × 12 LSO matrices, shifted by half a pitch. The pixel size was 0.9 × 0.9 mm2; the lengths were 10.0 mm and 5.0 mm, respectively. For a light sensor, we used a 4 × 4 SiPM array. The RF attenuation was measured from 320 kHz to 420 MHz using two pick-up coils. MRI-compatibility and shielding effect of the materials were evaluated with an MRI system. The average FWHM energy resolution at 511 keV of all 144 crystals of the layer next to the SiPM was deteriorated from 15.73 ± 0.24% to 16.32 ± 0.13%, 16.60 ± 0.25%, and 19.16 ± 0.21% by the ITO foil, 9900 foil, mesh material, respectively. The average peak-to-valley ratio of the PET detector changed from 5.77 ± 0.29 to 4.50 ± 0.39, 4.78 ± 0.48, 3.62 ± 0.16, respectively. The ITO, 9900, mesh attenuated the scintillation light by 11.3 ± 1.6%, 11.0 ± 1.8%, 54.3 ± 0.4%, respectively. To attenuate the RF from 20 MHz to 200 MHz, mesh performed better than copper. The results show that an RF shielding material that is sufficiently transparent for scintillation light and is MRI compatible can be obtained. This result enables the development of a fully integrated PET detector and MRI coil assembly.

Telemedically Supported Case Management of Living-Donor Renal Transplant Recipients to Optimize Routine Evidence-Based Aftercare: A Single-Center Randomized Controlled Trial.

Improving mid-term and long-term outcomes after solid organ transplantation is imperative, and requires both state-of-the-art transplant surgery and optimization of routine, evidence-based aftercare. This randomized, controlled trial assessed the effectiveness of standard aftercare versus telemedically supported case management, an innovative aftercare model, in 46 living-donor renal transplant recipients during the first posttransplant year. The model includes three components: (i) chronic care case management initiated after discharge, (ii) case management initiated in emerging acute care situations, and (iii) a telemedically equipped team comprising a transplant nurse case manager and two senior transplant physicians (nephrologist, surgeon). Analyses revealed a reduction of unplanned inpatient acute care, with considerable cost reductions, in the intervention group. The prevalence of nonadherence over the 1-year study period was 17.4% in the intervention group versus 56.5% in the standard aftercare group (p = 0.013). Only the intervention group achieved their pre-agreed levels of adherence, disease-specific quality of life, and return to employment. This comparative effectiveness study provides the basis for multicenter study testing of telemedically supported case management with the aim of optimizing posttransplant aftercare. The trial was registered with the German Clinical Trials Register (www.DRKS.de), DKRS00007634.

Unconventional magnetisation texture in graphene/cobalt hybrids.

Magnetic domain structure and spin-dependent reflectivity measurements on cobalt thin films intercalated at the graphene/Ir(111) interface are investigated using spin-polarised low-energy electron microscopy. We find that graphene-covered cobalt films have surprising magnetic properties. Vectorial imaging of magnetic domains reveals an unusually gradual thickness-dependent spin reorientation transition, in which magnetisation rotates from out-of-the-film plane to the in-plane direction by less than 10° per cobalt monolayer. During this transition, cobalt films have a meandering spin texture, characterised by a complex, three-dimensional, wavy magnetisation pattern. In addition, spectroscopy measurements suggest that the electronic band structure of the unoccupied states is essentially spin-independent already a few electron-Volts above the vacuum level. These properties strikingly differ from those of pristine cobalt films and could open new prospects in surface magnetism.