Comparison of European (ESR) and American (ACR) White Papers on Teleradiology: Patient Primacy Is Paramount

The ACR and European Society of Radiology white papers on teleradiology propose best practice guidelines for teleradiology, with each body focusing on its respective local situation, market, and legal regulations. The organizations have common viewpoints, the most important being patient primacy, maintenance of quality, and the “supplementary” position of teleradiology to local services. The major differences between the white papers are related mainly to the market situation, the use of teleradiology, teleradiologist credentialing and certification, the principles of “international” teleradiology, and the need to obtain “informed consent” from patients. The authors describe these similarities and differences by highlighting the background and context of teleradiology in Europe and the United States.     

RDW与不同类型急性阑尾炎的相关性分析

目的：探讨红细胞分布宽度（RDW）与不同病理类型急性阑尾炎（AA）的相关性。方法按照病理类型将 AA 患者分为单纯性、化脓性以及坏疽性三种病理类型的 AA 患者,将这三组患者的 RDW 均值进行两两比较,并分别与对照组进行比较。分析三类 AA 患者的 RDW 值与白细胞（WBC）计数的相关性,应用 ROC 曲线分析 RDW 对于不同类型 AA 的诊断价值。结果单纯性和化脓性 AA 患者的 RDW 值与对照组比较差异有统计学意义（P ＜0．05）,而与 WBC 计数无相关性（P ＞0．05）;坏疽性AA 的 RDW 值与对照组比较差异无统计学意义（P ＞0．05）,而与 WBC 计数呈正相关（r＝0．646,P ＜0．05）。结论RDW 与单纯性和化脓性 AA 存在相关性,RDW 的降低可以对单纯性 AA 和化脓性 AA 的诊断提供参考,但尚不能作为单纯性 AA 和化脓性AA 诊断的指标。     

WHITE MATTER INTEGRITY AND ITS RELATIONSHIP TO PTSD AND CHILDHOOD TRAUMA—A SYSTEMATIC REVIEW AND META‐ANALYSIS

Recent reviews and meta‐analyses reported structural gray matter changes in patients suffering from adult‐onset posttraumatic stress disorder (PTSD) and in subjects with and without PTSD who experienced childhood trauma. However, it remains unclear if such structural changes are also affecting the white matter. The aim of this systematic review is to provide a comprehensive overview of all empirical investigations measuring white matter integrity in populations affected by PTSD and/or childhood trauma. To this end, results from different methodological approaches were included. Twenty‐five articles are reviewed of which 10 pertained to pediatric PTSD and the effects of childhood trauma measured during childhood, seven to the effects of childhood trauma measured during adulthood, and eight to adult‐onset PTSD. Overall, reductions in white matter volume were reported more often than increases in these populations. However, the heterogeneity of the exact locations indicates only a weak overlap across published studies. In addition, a meta‐analysis was carried out on seven whole‐brain diffusion tensor imaging (DTI) studies in adults. Significant clusters of both increases and decreases were identified in various structures, most notably the cingulum and the superior longitudinal fasciculus. Future research directions are discussed.     

Investigating the prevalence of complex fiber configurations in white matter tissue with diffusion magnetic resonance imaging

It has long been recognized that the diffusion tensor model is inappropriate to characterize complex fiber architecture, causing tensor‐derived measures such as the primary eigenvector and fractional anisotropy to be unreliable or misleading in these regions. There is however still debate about the impact of this problem in practice. A recent study using a Bayesian automatic relevance detection (ARD) multicompartment model suggested that a third of white matter (WM) voxels contain crossing fibers, a value that, whilst already significant, is likely to be an underestimate. The aim of this study is to provide more robust estimates of the proportion of affected voxels, the number of fiber orientations within each WM voxel, and the impact on tensor‐derived analyses, using large, high‐quality diffusion‐weighted data sets, with reconstruction parameters optimized specifically for this task. Two reconstruction algorithms were used: constrained spherical deconvolution (CSD), and the ARD method used in the previous study. We estimate the proportion of WM voxels containing crossing fibers to be ～90% (using CSD) and 63% (using ARD). Both these values are much higher than previously reported, strongly suggesting that the diffusion tensor model is inadequate in the vast majority of WM regions. This has serious implications for downstream processing applications that depend on this model, particularly tractography, and the interpretation of anisotropy and radial/axial diffusivity measures. Hum Brain Mapp 34:2747–2766, 2013. © 2012 Wiley Periodicals, Inc.     

Characteristics of a Specific Radioimmunoassay for Measurement of Ferritin on the Surface of Peripheral Mononuclear White Blood Cells in Cancer Patients

Using ¹²⁵I-labeled rabbit anti-Hodgkin's spleen ferritin antibody (RHF), a simple radioimmunoassay has been developed for quantitation of ferritin on the surface of peripheral blood mononuclear white blood cells (PBM). This method makes use of a % specific binding determination (%SP) by measuring the amount of ¹²⁵I-labeled RHF bound to 1 × 10⁶ PBM in the presence and absence of soluble ferritin. To standardize this procedure, artificial ferritin positive control cells were prepared by covalently coupling ferritin to cultured acute lymphoblastic luekemia cells. These cells were tested on a daily basis in parallel with patient PBM's to ensure inter and intra-assay precision and remained stable for over two years. Characteristics of ¹²⁵I-labeled RHF binding to control and patient PBM's were evaluated to determine the specificity of interaction and optimum binding parameters. %SP was linear in the range of 1 × 10⁵ - 1 × 10⁶ PBM's and was progressively inhibited by graded concentrations of soluble ferritin. F(ab')₂ preparations of RHF were equally as effective as intact RHF in blocking ¹²⁵I-labeled RHF binding confirming that ¹²⁵I-labeled RHF was not binding non-specifically to PBM Fc receptors. Additional experiments describing kinetics and methods of standardization of new lots of ¹²⁵I-labeled RHF are also described.     

Delay structure of wideband noises with application to filtering problems

The paper presents a mathematical theory of handling and working with wideband noises. We demonstrate that a wideband noise can be represented as a distributed delay of a white noise. From this, we deduce that the behavior of a wideband noise is the same as the behavior of an infinite dimensional colored noise along the boundary line. All these are used to deduce a complete set of formulae for the Kalman‐type optimal filter and also to derive nonlinear filtering equation for wideband‐noise‐driven linear and nonlinear systems. Copyright © 2012 John Wiley & Sons, Ltd.