Mathematical modeling improves computed tomography diagnosis of traumatic aortic injury

RATIONALE AND OBJECTIVES: Acute traumatic aorta injuries (ATAIs) following blunt thoracic trauma require rapid and accurate diagnosis for institution of lifesaving treatment. The use of computed tomography (CT) in the diagnosis of such injuries continues to improve and has the potential to become the diagnostic modality of choice in many trauma centers. A standardized diagnostic model may contribute to improvements in radiologist interpretation of CT for ATAIs. MATERIALS AND METHODS: The following diagnostic criteria were used to develop a diagnostic model for ATAIs: 11 areas of potential hematoma formation were identified in the mediastinum. Maximum short- and long-axis cross-sectional diameters of the aorta were measured. Qualitative morphologic information (contour change, intimal flap) was recorded. Smoothness of the aorta wall was assessed. These characteristics were quantified and analyzed for statistical significance, allowing for the development of an injury assessment model. RESULTS: The diagnostic model was used to score 69 blunt thoracic trauma patient cases. Average weighted kappa was 0.74, showing strong agreement among two observers and reproducibility of the model. The model improved injury assessment by classifying equivocal cases as either positive or negative. The ROC curve calculated from the original radiologist interpretation contained 86.1% area under the curve, while the curve for the new model contained 97.5%. The likelihood ratio increased from 30.06 to 48.67. The degree to which the new measure improved prediction over the original radiologist reading was tested using a nested model and yielded a reliable increment in model fit (chi2 analysis: Deltachi2(3) = 20.929, P < or = .0001). Finally, beta weights calculated from each variable were used to create a quantitative best-fit diagnostic model for future use. CONCLUSION: We have developed a diagnostic tool that may help radiologists better evaluate CT for ATAIs.     

Feasibility of promoting smoking cessation among methadone users using multimedia computer-assisted education

Background

The prevalence of smoking is very high among methadone users. As a method of delivering health education, computers can be utilized effectively. However computer-assisted education in methadone users has not been evaluated systematically.

Objective

This study was aimed at assessing feasibility and patient acceptance of an interactive educational module of a multi-component smoking cessation counseling computer program for former illicit drug users treated in an outpatient methadone clinic.

Methods

The computer-mediated education for hazards of smoking utilized in this study was driven by major constructs of adult learning theories. The program interface was tailored to individuals with minimal computer experience and was implemented on a touch screen tablet PC. The number of consecutive methadone-treated current smokers enrolled in the study was 35. After providing socio-demographic and smoking profiles, the patients were asked to use the educational program for 40 minutes. The impact of the computer-mediated education was assessed by administering a pre- and post-intervention Hazards of Smoking Knowledge Survey (HSKS). An attitudinal survey and semi-structured qualitative interview were used after the educational session to assess the opinions of participants about their educational experience.

Results

The computer-mediated education resulted in significant increase of HSKS scores from 60.5 ± 16.3 to 70.4 ± 11.7 with t value 3.69 and P < .001. The majority of the patients (78.8%) felt the tablet PC was easy to use, and most of the patients (91.4%) rated the educational experience as good or excellent. After controlling for patient baseline characteristics, the effect of computer-mediated education remained statistically significant.

Conclusions

Computer-assisted education using tablet PCs was feasible, well-accepted, and an effective means of providing hazards of smoking education among methadone users.     

局部非线性函数灰阶变换图像处理法对数字化颈椎侧位影像质量的影响分析

1 资料与方法 1.1 病例选取 2008年5月-8月来我院就诊并进行颈椎侧位投照患者50例,男17例,女33例,年龄23～51岁,平均(32.7±1.0)岁. 1.2 投照设备与条件使用Kodak DR7100型放射成像系统;电压 70 kV;使用自动曝光控制;SID 1.5米.     

计算机辅助导航下膝关节置换术的手术配合

近年来随着计算机技术和空间示踪技术的发展与结合,计算机辅助导航手术系统受到临床广泛关注。计算机辅助导航系统可以准确、实时确定手术器械的位置和方向,从技术上为医生提供支援。     

3D coronary reconstruction from routine single-plane coronary angiograms: Clinical validation and quantitative analysis of the right coronary artery in 100 patients

Background: Current coronary angiographic techniques display complex three-dimensional (3D) coronary structures in two dimensions (2D). We have developed a 3D reconstruction (3DR) algorithm using standard single-plane angiographic images that allows for 3D display of coronary structures. The purpose of this study was to validate our 3DR algorithm and quantify anatomic characteristics of the right coronary artery (RCA) in vivo. Methods: Accuracy and reproducibility studies were performed using 3DRs of a coronary phantom and in vivo following 3DRs in 40 patients. The anatomic features of the RCA were then quantified in 100 patients. Results: Comparison of length and bifurcation angles (BA) from the phantom to the 3DRs revealed good accuracy and correlation for both (r = 0.95 and 0.93 respectively), with diameter error of <7%. In vivo, the average root mean square (RMS) error in the spatial coordinates of the vessel centerlines was 3.12 ± 0.77 and 3.16 ± 0.75 mm in 20 left coronary arteries (LCA) and 20 RCAs respectively. Interobserver average RMS error was 3.47 ± 1.96 mm and intraobserver average RMS error was 3.02 ± 1.07 and 3.44 ± 1.57 mm for two different operators (p = NS). The average RCA length was 10.2 ± 1.7 cm, average radius of curvature (ROC) was 52 ± 9°, and the average 3D bifurcation angle of the posterior descending artery (PDA) from the RCA was 55 ± 22°. Foreshortening (FS) of the segments of the RCA in three 'standard projections ranged from 0–60, 0–75, and 0–82% respectively. Conclusions: Using our 3DR algorithm patient-specific anatomic characteristics can be accurately displayed and quantified, expanding the information that can be derived from routine coronary angiography.     

16排螺旋CT肺血管造影及重建技术在老年人肺动脉栓塞诊断中的应用

目的 研究16层螺旋CT肺血管造影及重建技术在老年人肺动脉栓塞(肺栓塞)诊断中的应用.方法 24例疑为肺栓塞的老年患者应用16层螺旋CT行肺动脉成像.CT后重建技术包括最大密度投影(MIP)、多平面重建(MPR)及容积再现(VR).结果 24例老年患者共发现肺动脉栓子161个,肺栓塞的直接CT征象:完全闭塞27支(占16.8%),不规则的充盈缺损109支(67.7%),中心性充盈缺损(轨道征)25支(15.5%).横断面图像共检出栓子161个,MPR像共检出153个(95.0%),MIP像检出113个(70.2%),VR像检出69个(42.9%).MIP和VR图像对栓子的显示效果相对较差,尤其是对肺叶及其以下肺动脉分支内栓子的显示效果明显低于横断面组(x2值分别为235.36和243.4l,均P＜0.05).结论 16层螺旋CT肺血管造影无创、快速、敏感性高,应当作为老年人肺栓塞的首选检查方法.

Abstract：

Objective To study the application of pulmonary angiography and reconstruction techniques with 16-detector row spiral CT in the diagnosis of pulmonary embolism (PE) in the elderly.Methods Twenty-four elderly patients with suspected pulmonary thromboembolism received detection of CT and pulmonary artery angiography ( CTPA ) on 16-detector MSCT.Post-reconstruction techniques included maximum intensity projection (MIP), volume rendering (VR)and multiple planar reformation (MPR). Results A total of 161 pulmonary artery thrombi were detected in 24 elderly patients. The direct signs of pulmonary embolism included total occlusion (16.8%, 27/161), partial filling defect (67.7%, 109/161) and central filling defect or track sign (15.5%, 25/161). A total of 161 pieces of pulmonary thrombi were detected in transect image, 153 (95.0%) in MPR, 113 (70.2%) in MIP and 69 (42.9%) in VR. The transect image excelled evidently MIP and VR image in displaying pulmonary thrombi, especially the thrombi in pulmonary lobe and pulmonary artery branch (χ2 =235.36 and 243.41, P＜0.05). Conclusions The 16-detector row spiral CT pulmonary angiography is non-invasive, fast and high sensitive, it should be the first choice for the diagnosis of PE in the elderly.     

A novel method for automated assessment of megakaryocyte differentiation and proplatelet formation

Transfusion of platelet concentrates represents an important treatment for various bleeding complications. However, the short half-life and frequent contaminations with bacteria restrict the availability of platelet concentrates and raise a clear demand for platelets generated ex vivo. Therefore, in vitro platelet generation from megakaryocytes represents an important research topic. A vital step for this process represents accurate analysis of thrombopoiesis and proplatelet formation, which is usually conducted manually. We aimed to develop a novel method for automated classification and analysis of proplatelet-forming megakaryocytes in vitro. After fluorescent labelling of surface and nucleus, MKs were automatically categorized and analysed with a novel pipeline of the open source software CellProfiler. Our new workflow is able to detect and quantify four subtypes of megakaryocytes undergoing thrombopoiesis: proplatelet-forming, spreading, pseudopodia-forming and terminally differentiated, anucleated megakaryocytes. Furthermore, we were able to characterize the inhibitory effect of dasatinib on thrombopoiesis in more detail. Our new workflow enabled rapid, unbiased, quantitative and qualitative in-depth analysis of proplatelet formation based on morphological characteristics. Clinicians and basic researchers alike will benefit from this novel technique that allows reliable and unbiased quantification of proplatelet formation. It thereby provides a valuable tool for the development of methods to generate platelets ex vivo and to detect effects of drugs on megakaryocyte differentiation.     

超高分辨率CT靶扫描与CT靶重建在肺磨玻璃样结节定性诊断中的价值

目的 比较超高分辨率CT(UHRCT)靶扫描与常规CT靶重建的肺磨玻璃样结节微征象,分析这两种方法对肺磨玻璃样结节定性诊断的价值。方法 收集2016年8月至2017年12月在山东省胸科医院筛查疑诊为肺结核的患者120例。本组患者CT扫描均发现有肺内单发磨玻璃样结节影。患者行常规CT扫描,然后进行靶重建和UHRCT靶扫描,共计结节灶120个。由2名副高级以上诊断医师阅片,分析上述两种CT成像技术所显示的肺磨玻璃样结节征象(结节边缘、增粗肺纹理、结节内实性成分、毛刺征、空泡征、支气管征、胸膜牵拉征),分别定性诊断癌前病变[不典型腺瘤样增生(AAH)、肺原位腺癌(AIS)]、微浸润腺癌(MIA)、浸润腺癌(IAC),最终根据病理结果比较两种成像技术对肺腺癌分期诊断的正确率。采用SPSS 17.0软件进行统计学处理,计数资料用卡方检验,以P<0.05差异具有统计学意义。结果 结节边缘清晰,UHRCT靶扫描为71个(78.0%),CT靶重建为56个(61.5%)(χ ²=5.863,P=0.015)。肺纹理增粗,UHRCT靶扫描为60个(65.9%),CT靶重建为45个(49.5%)(χ ²=5.065,P=0.024)。结节内实性成分,UHRCT靶扫描为66个(72.5%),CT靶重建为50个(54.9%)(χ ²=6.086,P=0.014)。毛刺征UHRCT靶扫描为34个(37.4%),CT靶重建为29个(31.9%)(χ ²=0.319,P=0.572)。空泡征UHRCT靶扫描为22个(24.2%),CT靶重建为18个(19.8%)(χ ²=0.513,P=0.474)。支气管征UHRCT靶扫描为28个(30.8%),CT靶重建为26个(28.6%)(χ ²=0.105,P=0.746)。胸膜牵拉征UHRCT靶扫描为30个(33.0%),CT靶重建为21个(23.1%)(χ ²=2.207,P=0.137)。常规CT靶重建诊断与病理符合数为75个(82.4%),不符合数为16个(17.6%)。UHRCT靶扫描检查与病理符合数为86个(94.5%),不符合数为5个(5.5%)(χ ²=6.513, P=0.011)。 结论 UHRCT靶扫描较常规CT靶重建显示的肺磨玻璃样结节微征象更清楚,有助于对肺磨玻璃样结节的病理分期。     

直肠癌新辅助放化疗的探索

对于局部晚期直肠癌,美国NCCN指南或欧洲ESMO指南均推荐术前放疗或放化疗联合全直肠系膜切除术（total mesorectal excision,TME）作为标准的治疗模式,使局部晚期直肠癌的治疗疗效取得了显著提高。为进一步降低远处转移率、提高生存率,目前对多种新辅助治疗的模式展开了探索,并取得初步成效。