Oral contrast medium in PET/CT: should you or shouldn’t you?

Purpose It has been suggested that the use of computed tomography (CT) positive contrast agents has led to attenuation-induced artefacts on ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET/CT) systems. Consequently, centres may withhold the use of such agents. Whilst there is theoretical evidence to support the aforementioned claim, the clinical relevance of the induced artefacts has not been widely established. Moreover, the potential benefits of bowel enhancement on PET/CT have yet to be formally evaluated. We therefore prospectively examined PET/CT studies to assess whether the use of oral contrast medium induces clinically relevant artefacts and whether the use of these agents is diagnostically helpful.Methods Over a 2-month period, ¹⁸F-FDG PET/CT images were prospectively reviewed from 200 patients following Gastrografin administration 2 h prior to examination. Both a radiologist and a nuclear medicine physician reviewed the images for contrast medium-mediated clinically relevant artefacts. Artefacts were sought on the CT attenuation-corrected images and were compared with the appearance on non-attenuated-corrected images. The number of examinations in which the oral contrast aided image interpretation was also noted.Results There were no oral contrast medium-induced clinically significant artefacts. In 38 of the 200 patients, oral contrast aided image interpretation (owing to differentiation of mass/node from bowel, discrimination of intestinal wall from lumen or definition of the anatomy of a relevant site). In 33 of these 38 patients, the anatomical site of interest was the abdomen/pelvis.Conclusion The use of oral contrast medium in ¹⁸F-FDG PET studies should not be withheld as it improves image interpretation and does not produce clinically significant artefacts.     

Evaluation of a decision support system for interpretation of myocardial perfusion gated SPECT

PURPOSE: We have recently presented a decision support system for interpreting myocardial perfusion scintigraphy (MPS). In this study, we wanted to evaluate the system in a separate hospital from where it was trained and to compare it with a quantification software package. METHODS: A completely automated method based on neural networks was trained for the interpretation of MPS regarding myocardial ischaemia and infarction using 418 MPS from one hospital. Features from each examination describing rest and stress perfusion, regional and global function were used as inputs to different neural networks. After the training session, the system was evaluated using 532 MPS from another hospital. The test images were also processed with the quantification software package Emory Cardiac Toolbox (ECTb). The images were interpreted by experienced clinicians at both the training and the test hospital, regarding the presence or absence of myocardial ischaemia and/or infarction and these interpretations were used as gold standard. RESULTS: The neural network showed a sensitivity of 90% and a specificity of 85% for myocardial ischaemia. The specificity for the ECTb was 46% (p < 0.001), measured at the same sensitivity. The neural network sensitivity for myocardial infarction was 89% and the specificity 96%. The corresponding specificity for the ECTb was 54% (p < 0.001). CONCLUSION: A decision support system based on neural networks presents interpretations more similar to experienced clinicians compared to a conventional automated quantification software package. This study shows the feasibility of disseminating the expertise of experienced clinicians to less experienced physicians by the use of neural networks.     

Artificial Intelligence in Echocardiography

Artificial intelligence in diagnostic cardiac-imaging platforms is advancing rapidly. In particular, artificial intelligence algorithms have increased the efficiency and accuracy of echocardiographic cardiovascular imaging, resulting in more complex echocardiographic imaging techniques and expanded use among noncardiologists. Here, we provide an overview of real-world applications of artificial intelligence in echocardiography including automatic high-quality computer-optimized image acquisition sequences, automated measurements, and algorithms for the rapid and accurate interpretation of cardiac physiology. These advances will not replace physicians but will improve their productivity, workflow, and diagnostic performance.     

基于不同自我相关条件下抑郁情绪个体解释偏向的特点研究

目的 探讨抑郁情绪个体在不同自我相关条件下的歧义性信息中解释偏向的变化特点.方法 采用贝克抑郁自评量表第2版(BDI-Ⅱ)筛选出抑郁情绪组被试(n=20)及正常对照组被试(n=20).使用词句联想范式(WSAP)的行为学任务测量两组被试在不同自我相关条件下对歧义性信息的解释(词汇)认可率及反应时.数据采用SPSS 18.0进行统计分析.结果 ①抑郁情绪组与正常对照组在良性解释(词汇)、负性解释(词汇)的总体认可率、反应时上存在统计学差异(P＜0.01).②抑郁情绪组在3种不同自我相关度的条件下(无关的他人情境/亲密关系情境/自我情境)对良性解释(词汇)、负性解释(词汇)的认可率、反应时分别存在统计学差异(P ＜0.05,P＜0.01);正常对照组在3种不同自我相关度的条件下对良性解释(词汇)、负性解释(词汇)的认可率和反应时也分别存在统计学差异(P ＜0.05,P＜0.01).③在自我情境中,抑郁情绪组的负性解释(词汇)认可率最高且反应时最短;在亲密关系情境中,抑郁情绪组的良性解释(词汇)认可率最高且反应时最短.结论 抑郁情绪个体在歧义信息的解释加工过程中,存在显著的负性解释偏向及可能的良性解释偏向缺乏,其中负性解释偏向同时存在于自我与非自我相关情境.     

中医经典词语“阴阳”诠释

通过对《黄帝内经》、《难经》、《伤寒杂病论》、《神农本草经》中所见“阴阳”一词的涵义分析,首次全面系统梳理了“阴阳”一词在上述四大经典中的全部义项,并以注家释义作为语证。     

髋关节脱位Salter手术前后股骨头覆盖率的计算机图像分析

目的通过计算机图像分析探讨髋关节脱位患儿Salter骨盆截骨手术前后股骨头覆盖率的变化。方法对20例单侧髋关节脱位患儿行Salter截骨手术并对术前术后影像学资料进行分析。测量CE角及股骨头的覆盖率，分别比较其手术前后的变化，以正常侧作为对照组。结果髋脱位患儿术后CE角与股骨头覆盖率较术前均有明显改善，术后CE角和CT的股骨头覆盖率无正相关关系。结论通过计算机图像分析可以更加清晰、直观地了解股骨头的覆盖情况；Salter骨盆截骨手术在空间上改变了髋臼的方向，对股骨头的覆盖明显增加．     

Computer-assisted cystoscopy diagnosis of bladder cancer

Objectives

One of the most reliable methods for diagnosing bladder cancer is cystoscopy. Depending on the findings, this may be followed by a referral to a more experienced urologist or a biopsy and histological analysis of suspicious lesion. In this work, we explore whether computer-assisted triage of cystoscopy findings can identify low-risk lesions and reduce the number of referrals or biopsies, associated complications, and costs, although reducing subjectivity of the procedure and indicating when the risk of a lesion being malignant is minimal.

影响结直肠癌肝转移手术切除患者预后的多因素分析

目的 探讨影响结直肠癌肝转移患者手术切除的预后因素。方法 收集1995-2001年间收治的结直肠癌肝转移手术切除患者103例的资料，用Kaplan-Meier法计算术后生存率，以Cox模型进行多变量分析。结果 患者术后1、3年无瘤生存率分别为73．8％和43．7％，术后1、3年累积生存率分别为7g．6％和49．5％。单因素分析显示：术前血清CEA水平、转移灶与原发灶的治疗间隔时间、术中切缘情况、肝门淋巴结转移、肝内卫星灶的存在与否、肝转移灶的最大直径、数目及有无包膜影响患者的术后肝内复发和术后累积生存率，而术后化疗可以提高患者的累积生存率。多因素分析显示：转移灶与原发灶的治疗间隔时间、切缘情况、肝内卫星灶的存在与否和肝转移灶的最大直径是影响肝内复发和累积生存率的独立因素，而肝门淋巴结转移是影响累积生存率的独立因素，有无包膜是影响肝内复发的独立因素。结论 手术切除是结直肠癌肝转移有效的治疗手段。转移灶与原发灶的治疗间隔时间、切缘情况、肝内卫星灶、肝转移灶的大小和包膜、肝门淋巴结转移等是患者预后的独立影响因素。     

The School Dropout

This paper provides a commentary on Philip Cushman's “A Burning World, an Absent God: Midrash, Hermeneutics, and Relational Psychoanalysis.” Cushman creatively uses the rabbinic midrash as a model hermeneutic and dialogic tradition for contemporary psychoanalysis as an alternative to fundamentalist interpretation. I agree with Cushman's goal, but I find that he places greater emphasis on absence over presence, narrative over law, transcendence over immanence, change over continuity, revolution over evolution, construction over discovery, and individual freedom and autonomy over community and tradition. I believe that it is just this leaning to one side that leaves him defensive about the collapse to relativism. Holding these poles in greater tension and valuing both sides of these polarities offers a dialectical model that serves contemporary psychoanalysis better as a hermeneutic, dialogical, contextual, and dialectical model for interpretation.