Transfer patient imaging: a survey of members of the American Society of Emergency Radiology

When trauma patients are transferred from outside hospitals, the receiving clinicians often consult their local radiologists for definitive interpretations of outside examinations (IOE). Such requests introduce a host of logistical, medicolegal, and financial concerns related to quality control and resource utilization. We surveyed 701 members of the American Society of Emergency Radiology to elucidate these concerns. We found that the majority of emergency departments still rely on compact disks for conveyance of outside images; hard film and network transfers were minor mechanisms for most respondents. Sixty-nine percent of the respondents indicated that radiologist reports accompany fewer than 25?% of all transferred imaging studies; of the reports that do arrive, most are unverified preliminary reads. There is considerable variability in billing practices and reimbursement patterns for radiologic second opinions; 68?% of the respondents do not know how often their IOEs are reimbursed. Suboptimal communication between community hospitals and referral centers may result in duplicated efforts and inconsistent quality of medical imaging studies. Further investigation into the role of radiology trainees in the handling of outside studies is also highly recommended.     

2016 SCCT/STR guidelines for coronary artery calcium scoring of noncontrast noncardiac chest CT scans: A report of the Society of Cardiovascular Computed Tomography and Society of Thoracic Radiology

The Society of Cardiovascular Computed Tomography (SCCT) and the Society of Thoracic Radiology (STR) have jointly produced this document. Experts in this subject have been selected from both organizations to examine subject-specific data and write this guideline in partnership. A formal literature review, weighing the strength of evidence has been performed. When available, information from studies on cost was considered. Computed tomography (CT) acquisition, CAC scoring methodologies and clinical outcomes are the primary basis for the recommendations in this guideline. This guideline is intended to assist healthcare providers in clinical decision making. The recommendations reflect a consensus after a thorough review of the best available current scientific evidence and practice patterns of experts in the field and are intended to improve patient care while acknowledging that situations arise where additional information may be needed to better inform patient care.     

床位变化对SPECT/CT同机图像配准的影响

目的探讨检查床在有、无负重,不同负重状态下,硬件配准误差对单光子发射计算机断层成像技术/计算机体层摄影(SPECT/CT)同机融合图像质量的影响。材料与方法制作放射线源模型,在检查床有、无负重,负重不同状态下分别进行SPECT/CT图像采集,进行同机图像融合后用图像软件分析并测量SPECT与CT融合图像偏差程度。结果检查床上0负荷时同机图像融合配准较准确,两种图像中心偏移平均2mm。加载50kg与100kg重量后,床位移动过程中Y轴会出现偏差,最大偏差为4.3mm,平均偏差为2.3mm,但差异无统计学意义(P>0.05)。结论在负重状态下床位变化导致SPECT/CT同机图像融合配准有细微偏差,但不会影响图像融合质量。     

A new helical computed tomographic technique for appendiceal imaging: Preliminary experience with the focused appendix computed tomographic examination

Our objective was to describe a new, helical computed tomographic (CT) technique for evaluating appendicitis, the focused appendix CT (FACT), and report preliminary experience with its use.Thirty-five consecutive patients were selected on the basis of clinical suspicion for appendicitis. Patients received oral and colon contrast media but not intravenous contrast medium before CT scanning. A thinsection, contiguous helical scan limited to the lower abdomen and upper pelvis was performed. Each scan was interpreted as positive or negative for appendicitis, and any alternative pathology was noted, if present.Seventeen patients had a final diagnosis of appendicitis at surgery and pathology, and 18 patients had appendicitis excluded at clinical follow-up for at least 3 months (17 patients) or at surgeryand pathology (1 patient). FACT interpretations were correct in all cases. Alternative pathology was noted in 13 of the 18 cases (72%) interpreted as negative for appendicitis.     

Standardization of teleradiology using Dicom e-mail: recommendations of the German Radiology Society

Until recently there has been no standard for an interoperable and manufacturer-independent protocol for secure teleradiology connections. This was one of the main reasons for the limited use of teleradiology in Germany. Various teleradiology solutions have been developed in the past, but the vast majority have not been interoperable. Therefore an ad hoc teleradiology connection was impossible even between partners who were already equipped with teleradiology workstations. Based on the evaluation of vendor-independent protocols in recent years the IT Working Group (AGIT) of the German Radiology Society set up an initiative to standardize basic teleradiology. An e-mail based solution using the Dicom standard for e-mail attachments with additional encryption according to the OpenPGP standard was found to be the common denominator. This protocol is easy to implement and safe for personalized patient data and fulfills the legal requirements for teleradiology in Germany and other countries. The first version of the recommendation was presented at the 85th German Radiology Convention in 2004. Eight commercial and three open-source implementations of the protocol are currently available; the protocol is in daily use in over 50 hospitals and institutions.     

Variability in the practice of emergency radiology: a survey of the members of the American Society of Emergency Radiology

Objective: To assess the variation in practice for selected clinical scenarios among members of the American Society of Emergency Radiology. Methods: A survey was distributed to assess the standard imaging approach to nine common emergency radiology clinical scenarios. Institutional demographics were also assessed. The respondent's institution was used as the primary unit of analysis. Results: A total of 140 institutions were included in the primary analysis. Major variation was identified in the imaging approach to all scenarios studied. Practice size and type did not explain the variation. However, significant differences (P < 0.006) were observed between practice in the United States and the remainder of the world. Conclusions: There is no consensus among the members of the American Society of Emergency Radiology as to the best imaging approach to nine common clinical problems. The identification of this variation may serve as the seed for future research and discussion.     

PACS: the silent revolution

More than 15 years ago the idea of a Picture Archiving and Communication System (PACS) and a filmless hospital was created. In a PACS environment images are acquired, read, communicated and stored digitally. After many years of unsuccessful attempts and prototype installations, the necessary hardware components for a successful PACS installation are now readily available. However, software development is still lagging behind. Only very recently, software developers have realized that it is not sufficient for PACS software to store, communicate and display images, but that PACS software should effectively support the radiologist in the task of interpreting and communicating imaging findings through context-dependent default display arrangements, work-flow management, radiological and hospital information systems integration, and computer-assisted diagnosis. This review examines hard- and software requirements for efficient PACS operation, analyses costs and benefits, and discusses future developments. Received: 26 October 1998; Revision received: 11 January 1999; Accepted: 4 February 1999     

人工智能在冠状动脉CT血管成像后处理和诊断报告的初步评估

目的 探讨人工智能（AI）在冠状动脉CT血管造影（CCTA）的图像后处理和诊断报告中的应用价值。 方法 选取重庆医科大学附属第三医院于2019年4月至7月就诊的64例疑似冠心病患者,其中男性40例、女性24例,年龄（62.16±14.13）岁。所有患者均行CCTA扫描,按照李克特量表评分标准对原始图像质量进行评分,分别进行人工和AI图像后处理,比较二者的用时及合格率、诊断报告的用时及对冠状动脉斑块的诊断效能。 结果 CCTA扫描后,冠状动脉AI图像后处理的时间约3 min,合格率为92.2%（59/64）;人工后处理的时间为20~30 min。与人工处理相比,冠状动脉AI后处理的图像中冠状动脉管壁更光滑、小分支显示更全面、血管对比更清晰,并且能自动识别冠状动脉狭窄。冠状动脉AI图像的诊断报告在图像重建后即可完成（<1 min）,而人工的诊断报告需15 min左右才能完成。冠状动脉AI与人工对冠状动脉斑块检出的灵敏度几乎一致,分别为93.3%和92.0%;人工诊断报告对斑块检出的特异度达100%,而AI的特异度为93.8%。 结论 冠状动脉AI在图像后处理速度、图像质量及报告诊断的效率方面具有一定优势,有望成为CCTA分析的有效辅助工具。     

The American College of Radiology strategy for managing incidental findings on abdominal computed tomography

There has been a dramatically increased awareness of the substantial clinical challenges posed by incidental findings found on cross-sectional imaging. In 2006, an Incidental Findings Committee was organized under the Body Imaging Commission in the American College of Radiology to create a consistent and rational approach to these findings. This article describes the formation, process of developing recommendations, and future tasks of this committee.     

Irreversible JPEG 2000 compression of abdominal CT for primary interpretation: assessment of visually lossless threshold

To estimate the visually lossless threshold for Joint Photographic Experts Group (JPEG) 2000 compression of contrast-enhanced abdominal computed tomography (CT) images, 100 images were compressed to four different levels: a reversible (as negative control) and irreversible 5:1, 10:1, and 15:1. By alternately displaying the original and the compressed image on the same monitor, six radiologists independently determined if the compressed image was distinguishable from the original image. For each reader, we compared the proportion of the compressed images being rated distinguishable from the original images between the reversible compression and each of the three irreversible compressions using the exact test for paired proportions. For each reader, the proportion was not significantly different between the reversible (0–1%, 0/100 to 1/100) and irreversible 5:1 compression (0–3%). However, the proportion significantly increased with the irreversible 10:1 (95–99%) and 15:1 compressions (100%) versus reversible compression in all readers (P < 0.001); 100 and 95% of the 5:1 compressed images were rated indistinguishable from the original images by at least five of the six readers and all readers, respectively. Irreversibly 5:1 compressed abdominal CT images are visually lossless and, therefore, potentially acceptable for primary interpretation. This study was supported by Seoul R&BD Program, Republic of Korea (project number, 10675).     

Validation of Deep-Learning Image Reconstruction for Low-Dose Chest Computed Tomography Scan: Emphasis on Image Quality and Noise

ObjectiveIterative reconstruction degrades image quality. Thus, further advances in image reconstruction are necessary to overcome some limitations of this technique in low-dose computed tomography (LDCT) scan of the chest. Deep-learning image reconstruction (DLIR) is a new method used to reduce dose while maintaining image quality. The purposes of this study was to evaluate image quality and noise of LDCT scan images reconstructed with DLIR and compare with those of images reconstructed with the adaptive statistical iterative reconstruction-Veo at a level of 30% (ASiR-V 30%).Materials and MethodsThis retrospective study included 58 patients who underwent LDCT scan for lung cancer screening. Datasets were reconstructed with ASiR-V 30% and DLIR at medium and high levels (DLIR-M and DLIR-H, respectively). The objective image signal and noise, which represented mean attenuation value and standard deviation in Hounsfield units for the lungs, mediastinum, liver, and background air, and subjective image contrast, image noise, and conspicuity of structures were evaluated. The differences between CT scan images subjected to ASiR-V 30%, DLIR-M, and DLIR-H were evaluated.ResultsBased on the objective analysis, the image signals did not significantly differ among ASiR-V 30%, DLIR-M, and DLIR-H (p = 0.949, 0.737, 0.366, and 0.358 in the lungs, mediastinum, liver, and background air, respectively). However, the noise was significantly lower in DLIR-M and DLIR-H than in ASiR-V 30% (all p < 0.001). DLIR had higher signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) than ASiR-V 30% (p = 0.027, < 0.001, and < 0.001 in the SNR of the lungs, mediastinum, and liver, respectively; all p < 0.001 in the CNR). According to the subjective analysis, DLIR had higher image contrast and lower image noise than ASiR-V 30% (all p < 0.001). DLIR was superior to ASiR-V 30% in identifying the pulmonary arteries and veins, trachea and bronchi, lymph nodes, and pleura and pericardium (all p < 0.001).ConclusionDLIR significantly reduced the image noise in chest LDCT scan images compared with ASiR-V 30% while maintaining superior image quality.     

Pediatric CT scan usage in Japan: results of a hospital survey

Purpose The aim of this study was to examine the usage parameters of diagnostic computed tomography (CT) in children because of concerns of possible overuse in Japanese hospitals, including the “technical” CT exposure settings and the “clinical” grounds for CT requests. Materials and methods We examined the methodology at the radiology department to reduce radiation exposure to children and performed a retrospective study on pediatric CT requests during a 1-year period at Nagasaki University Hospital. The parameters of diagnostic CT usage for minor head trauma and acute appendicitis were studied in detail. Results CT radiation dose settings are adjusted for children based on guidelines issued by the Japan Radiological Society, with few limitations. CT requests were made for 62% of minor head trauma cases and 76% of cases clinically suspected to be acute appendicitis. These figures are considerably higher than those reported by studies in the United Kingdom, Canada, or the United States. No specific guidelines are advocated regarding CT usage for minor head trauma. The diagnosis of acute appendicitis in children is almost routinely referred for “confirmation” by CT. Conclusion CT radiation risks to children at Japanese hospitals need to be considered more seriously. Physicians should be encouraged to follow diagnostic algorithms that help avoid unnecessary CT usage in children.     

Helical computed tomography of liver injuries: A trial of dual phase imaging

This study was performed to evaluate whether consecutive arterial phase and portal venous phase scans of the upper abdomen are contributory in the evaluation of the liver in patients with blunt abdominal trauma. The purpose of the study was to determine whether such dual acquisition using helical computed tomography (HCT) provides improved definition of injuries and significant information about the dynamics of posttraumatic hemorrhage.During a 10-month period, all patients referred for evaluation of blunt abdominal trauma were scanned using a dual phase imaging technique. Two consecutive and comparable scan clusters were programmed to study the upper abdomen, with a slice collimation of 10 mm and a 11 pitch. Intravenous contrast medium was delivered at a rate of 2 ml/sec for a total of 125 ml, with scan delays of 30 and 70 seconds (arterial and venous phases of hepatic enhancement).Thirty-two patients with hepatic lacerations were encountered, and the images from both acquisitions were compared and graded according to lesion conspicuity. The presence of contrast medium extravasation associated with parenchymal injuries was also recorded.In 23 (72%) of the 32 patients, the liver injuries were better defined in the portal venous phase, and in eight (25%) patients, the lesions were equally shown in both phases. In only one case, the lesion was better demonstrated in the arterial phase. Contrast medium extravasation was noted in two patients at the site of liver laceration. In three additional cases, contrast medium extravasation was also noted in associated splenic injuries. In all of these patients, the extravasation (bleeding laceration) was seen only in the images corresponding to the portal venous phase.Dual phase HCT of the upper abdomen does not provide significant additional information in the evaluation of patients with liver injuries resulting from blunt abdominal trauma. With a single scan cluster through the upper abdomen after a 70-second injection-scan delay, lesion definition is optimal, and vascular opacification remains adequate.     

BPL重建技术对18F-FDG PET/CT正常组织的代谢参数及图像质量的影响

目的探讨贝叶斯正则化似然(BPL)重建技术对18F-脱氧葡萄糖(FDG)PET/CT正常组织代谢参数及图像质量的影响。方法回顾性分析2019年3月至2019年6月间烟台毓璜顶医院60例肿瘤患者[男29例,女31例,年龄24~89(60.4±15.2)岁]的PET/CT体部检查数据,将PET图像按照有序子集最大期望值迭代法(OSEM)、飞行时间(TOF)+点扩散函数(PSF)和BPL(β值=350)3种重建技术进行重建,分别于右肺上叶、肝脏右后叶、主动脉根部和腰椎勾画感兴趣体积(VOI),测量VOI代谢参数[包括平均标准摄取值(SUVmean)、最大标准摄取值(SU_Vmax)、瘦体质量标准摄取值(SUV)峰值(SU_Lpeak)、SUV标准差(SUVSD)],并计算信噪比(SNR),分析SNR变化率(%ΔSNR)与体质指数(BMI)的关系。采用单因素方差分析、最小显著差异t检验和Pearson相关分析数据。结果3种重建技术的正常肺、主动脉、肝脏及腰椎的SUVmean及SU_Lpeak差异均无统计学意义(F值:0.04~1.95,均P>0.05)。BPL组正常肺、主动脉、肝脏和腰椎的SU_Vmax(1.14±0.82、2.13±0.37、2.95±0.50和2.76±0.87)较TOF+PSF组(1.56±0.61、2.99±0.75、4.32±0.94和4.05±1.48)和OSEM组(1.51±0.67、3.00±0.70、4.45±1.12和3.81±1.06)明显降低(F值:20.59~52.24,均P<0.001);SUVSD(0.13±0.07、0.20±0.05、0.26±0.06和0.38±0.17)较TOF+PSF组(0.24±0.11、0.43±0.11、0.58±0.15和0.67±0.21)和OSEM组(0.21±0.09、0.42±0.10、0.58±0.14和0.63±0.20)也明显降低(F值:24.46~124.95,均P<0.001);而SNR(4.67±1.34、7.74±2.22、8.17±1.77和4.45±1.22)则明显高于TOF+PSF组(2.54±0.72、3.55±0.82、3.77±0.91和2.49±0.69)和OSEM组(2.65±0.64、3.67±0.80、3.75±0.87和2.60±0.67;F值:83.04~247.73,均P<0.001);而TOF+PSF组与OSEM组间比较,代谢参数、SUVSD和SNR差异均无统计学意义(均P>0.05)。BPL重建组SNR随着BMI的增加而增加,且BMI<25 kg/m2和BMI≥30 kg/m2组之间主动脉SNR(7.07±2.21和9.67±2.26)和肝脏SNR(7.75±1.85和9.32±0.70)差异有统计学意义(F值:3.46、4.19,均P<0.05)。BPL重建后,OSEM和TOF+PSF组肺、主动脉、肝脏和腰椎的%ΔSNR与BMI呈正相关(r值:0.042~0.354,均P<0.05)。结论与传统的OSEM及TOF+PSF相比,BPL重建技术在稳定正常本底组织代谢参数的前提下,明显降低图像噪声、提高SNR,能够很大程度改善图像质量,尤其对体质量大的受检者的图像质量的改善更加明显。     

Radiology of the ambient cistern Part II: Pathology

Summary A combination of computed tomography and angiography permits accurate detailed evaluation of common lesions of the ambient cistern.     

PACS服务器架构在应急处理方案中的应用价值

目的探讨PACS服务器架构模式在应急处理方案中的应用价值。方法针对我院影像设备多及数据流量大的特点,PACS服务器设计采用分级体系管理架构。信息中心设立企业级服务器2台,1台为中心服务器,1台作为后备服务器,完成所有影像及病人资料接收、存储、调度及分发等服务,影像科及临床科分别设置2台(可扩充)影像前置服务器及1台临床前置服务器(可扩充),解决大并发访问对主服务器的压力及多个服务器之间的相互热备;开发提供一套科研教学前置服务器,用于教学及科研资料的存储及调阅。结果服务器分级体系架构在PACS遇到故障或灾难时,如中心服务器单点故障、中心服务器整体系统不可用或某个前置服务器系统不可用3种情况下,均能进行相应的应急处理,确保整个PACS系统正常运行。结论采用服务器分级架构体系强调多个服务器之间的相互热备,对于保障发生灾难性故障时整个系统的安全性具有重大的意义。