Feasibility of a method for low contrast CT image quality assessment using difference detail curves for abdominal scans

This work describes a measurement method for assessing dose-related image-quality of CT scans based on the difference detail curve (DDC) method, and showcases its use in a low contrast setting. The method is based on a phantom consisting of elliptical slices of different sizes into which contrast object modules can be inserted. These modules contain contrast objects based on (synthetic) resin mixtures with sucrose (native) or sodium iodine (contrast medium). Mixing ratios are provided to achieve a range of clinically relevant CT-numbers with these materials. The phantom is characterized in terms of contrast accuracy, energy dependency and long-term drift with satisfying results. Contrast accuracy and energy dependency are similar to that of water or soft tissue. Image quality of 655 scans of the phantom acquired at 30 different clinical institutions and with 16 different CT scanner models from 4 manufacturers was assessed by calculating a difference detail curve (DDC) from evaluation of up to 5 human observers using a custom-made software (RadiVates) described in this work. Based on these measurements, inter-observer variability was quantified using a bootstrap method and was shown to be a large contributor to the overall variability. This work demonstrates that assessment of CT image quality is feasible with the aforementioned phantom and DDC method.     

腹腔镜精准肝切除术治疗原发性肝癌的临床效果

目的探究腹腔镜精准肝切除术治疗原发性肝癌的临床效果。方法选择2019年1月—2020年6月期间在医院接受腹腔镜肝切除术治疗的80例原发性肝癌患者作为实验分析对象,依据手术治疗方案的不同将患者分为腹腔镜常规肝切除组(对照组)40例和腹腔镜精准肝切除组(观察组)40例,对两组患者手术各项指标、手术前后肝功能指标改善情况及术后并发症发生率进行对比分析。结果观察组患者手术时间明显长于对照组,组间比较进行t检验,差异具有统计学意义(P<0.05);观察组患者术中出血量及术中输血量均少于对照组患者,术后恢复时间明显短于对照组患者,组间比较进行t检验,差异具有统计学意义(P<0.05);术后,两组患者ALT、AST、ALB及TBIL水平均显著降低,组内比较进行t检验,差异具有统计学意义(P<0.05),观察组患者ALT、AST、ALB及TBIL水平降低幅度显著大于对照组患者,组间比较进行t检验,差异具有统计学意义(P<0.05);观察组患者术后并发症发生率为10.00%,对照组患者术后并发症发生率为27.50%,组间比较进行χ2检验,差异具有统计学意义(χ2=4.021;P=0.045)。结论与腹腔镜常规肝切除术比较,腹腔镜精准肝切除术操作精细,手术时间相对较长,患者术中出血量更少,术后恢复时间更短,能够最大限度保护患者的肝脏,减低患者术后并发症发生率,提高手术治疗效果,改善患者预后。     

Implementation of a Semistructured Clinical Event Documentation Tool for Acute Adverse Contrast Reactions

PurposeTo improve the efficiency and accuracy of clinicians documenting acute clinical events related to contrast agent administration using a web browser–based semistructured documentation support tool.MethodsA new tool called Contrast Incident Support and Reporting (CISaR) was developed to enable radiologists responding to contrast reactions to document inciting contrast class, type of event, severity of contrast reaction, and recommendation for future contrast use. Retrospective analysis was conducted of all CT and MRI examinations performed between February 2018 and December 2019 across our hospital system with associated contrast reaction documentation. Time periods were defined as before tool deployment, early adoption, and steady-state deployment. The primary outcome measure was the presence of event documentation by a radiologist. The secondary outcome measure was completeness of the documentation parameters.ResultsA total of 431 CT and MRI studies with reactions were included in the study, and 50% of studies had radiologist documentation during the pre-CISaR period. This increased to 66% during the early adoption period and 89% in the post-CISaR period. It took approximately 9 months from the introduction of CISaR to reach full adoption and become the main method for adverse contrast reaction documentation. The percentage of radiologist documentation that detailed provoking contrast agent class, severity of reaction, reaction type, and future contrast agent recommendation all significantly increased (P < .0001), with greater than 95% inclusion of each element.ConclusionThe implementation of a semistructured electronic application for adverse contrast reaction reporting significantly increased radiologist documentation rate and completeness of the documentation.     

乳腺对比增强能谱X线摄影的研究现状北大核心

对比增强能谱X线摄影(contrast enhancement spectral mammography, CESM)是在普通X线检查的基础上结合血管造影剂进行检查的一种新技术,是通过注射造影剂有效消除组织重叠对病灶的遮盖,实现对肿块真实形态显示,并提供血供信息。目前临床上对CESM进行了一系列的研究,本文就CESM成像原理、对乳腺癌的诊断、应用前景几个方面进行综述。     

对比四维子宫输卵管超声造影与子宫输卵管造影评估输卵管通畅性效能:Meta分析

目的 采用Meta分析对比四维子宫输卵管超声造影（4D-HyCoSy）与子宫输卵管造影（HSG）评估输卵管通畅性的效能。方法 系统搜索PubMed、Cochrane Library、Embase、Web of Science、中国生物医学文献数据库、中国知网、万方医学网及维普数据库中建库至今有关4D-HyCoSy和/或HSG评估输卵管通畅性的文献。由2名研究人员依据纳入标准和排除标准筛选文献并提取信息；分别计算4D-HyCoSy和HSG评估输卵管通畅性的合并敏感度（SEN）、特异度（SPE）及诊断比值比（DOR），绘制综合受试者工作特征（SROC）曲线，获得曲线下面积（AUC），并以Medcalc 19.1.1统计软件比较AUC。结果 最终纳入19篇文献、1 358例疑似输卵管因素导致不孕患者，其中4篇同时采用4D-HyCoSy及HSG评估输卵管通畅性，10篇仅以4D-HyCoSy评估，5篇仅以HSG评估。Meta分析结果显示，4D-HyCoSy评估输卵管通畅性的合并SEN、SPE及DOR分别为0.92[95%CI（0.91，0.94）]、0.91[95%CI（0.89，0.93）]及115.06[95%CI（54.23，224.10）]；HSG评估输卵管通畅性的合并SEN、SPE及DOR分别为0.84[95%CI（0.81，0.87）]、0.80[95%CI（0.76，0.83）]及28.64[95%CI（10.08，81.35）]。4D-HyCoSy评估输卵管通畅性的AUC为0.98[95%CI（0.96，0.99）]，HSG为0.93[95%CI（0.90，0.95）]，差异有统计学意义（Z=6.97，P<0.01）。结论 4D-HyCoSy评估输卵管通畅性的效能高于HSG。     

Ostium primum atrial septal defect with persistent left superior vena cava opening into unroofed coronary sinus—A rare entity

Raghib syndrome is a rare developmental complex consisting of termination of the left superior vena cava in the left atrium, absence of the coronary sinus, and an atrial septal defect commonly located at the posterior‐inferior angle of the atrial septum. This complex was considered unique to Raghib syndrome; however, cases with a normal atrial septum have been reported where the orifice of the unroofed coronary sinus functions as the inter‐atrial communication. Our patient demonstrated an isolated persistent left superior vena cava draining into the left atrium through unroofed coronary sinus and presence of ostium primum atrial septal defect.     

Updated Clinical Practice Guideline on Use of Gadolinium-Based Contrast Agents in Kidney Disease Issued by the Canadian Association of Radiologists

In 2017, the Canadian Association of Radiologists issued a clinical practice guideline (CPG) regarding the use of gadolinium-based contrast agents (GBCAs) in patients with acute kidney injury (AKI), chronic kidney disease (CKD), or on dialysis due to mounting evidence indicating that nephrogenic systemic fibrosis (NSF) occurs with extreme rarity or not at all when using Group II GBCAs or the Group III GBCA gadoxetic acid (compared to first generation Group I linear GBCAs). One of the goals of the work group was to re-evaluate the CPG after 24 months to determine the effect of more liberal use of GBCA on reported cases of NSF in patients with AKI, CKD Stage 4 or 5 (estimated glomerular filtration rate [eGFR] < 30 mL/min/1.73 m²), or those that are dialysis-dependent. A comprehensive review of the literature was conducted by a subcommittee of the initial CPG panel between the dates of January 1, 2017-December 31, 2018 to identify new unconfounded cases of NSF linked to Group II or Group III GBCAs and an updated CPG developed. To our knowledge, when using a Group II or Group III GBCA between 2017-2018, only a single unconfounded case report of a fibrosing dermopathy has been reported in a patient who received gadobenate dimeglumine with Stage 2 CKD. No other unconfounded cases of NSF have been reported with Group II or III agents in during this timeframe. The subcommittee concluded that the main recommendations from the 2017 CPG should remain unaltered, but agreed that screening for renal disease in the outpatient setting is no longer justifiable, cost-effective or recommended. Patients on hemodialysis (HD) should, however, be identified prior to GBCA administration to arrange timely HD to optimize gadolinium clearance, although there remains no evidence that HD reduces the risk of NSF. When administering Group II or III GBCAs to patients with AKI, on dialysis or with severe CKD, informed consent relating to NSF is also no longer explicitly recommended.     

On the Relationship between Dynamic Contrast-Enhanced Ultrasound Parameters and the Underlying Vascular Architecture Extracted from Acoustic Angiography

Dynamic contrast-enhanced ultrasound (DCE-US) has been proposed as a powerful tool for cancer diagnosis by estimation of perfusion and dispersion parameters reflecting angiogenic vascular changes. This work was aimed at identifying which vascular features are reflected by the estimated perfusion and dispersion parameters through comparison with acoustic angiography (AA). AA is a high-resolution technique that allows quantification of vascular morphology. Three-dimensional AA and 2-D DCE-US bolus acquisitions were used to monitor the growth of fibrosarcoma tumors in nine rats. AA-derived vascular properties were analyzed along with DCE-US perfusion and dispersion to investigate the differences between tumor and control and their evolution in time. AA-derived microvascular density and DCE-US perfusion exhibited good agreement, confirmed by their spatial distributions. No vascular feature was correlated with dispersion. Yet, dispersion provided better cancer classification than perfusion. We therefore hypothesize that dispersion characterizes vessels that are smaller than those visible with AA.