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肺PET图像的定量分析:挑战和机遇

中华核医学与分子影像杂志 2019年第11期39卷 698-704页

作者：陈聪霞(译) 李文婵(译) 郭悦(译) 姚稚明(审校者) Delphine L.Chen joseph Cheriyan Edwin R.Chilvers Gourab Choudhury Christopher Coello Martin Connell Marie Fisk Ashley M.Groves Roger N.gunn Beverley F.Holman Brian F.Hutton Sarah Lee William MacNee Divya Mohan David Parr Deepak Subramanian Ruth Tai-Singer Kris Thielemans Edwin j.R.van Beek Laurence Vass jeremy W.Wellen Ian Wilkinson Frederick j.Wilson 北京医院核医学科、国家老年医学中心 100730 Mallinckrodt Institute of Radiology Washington University School of MedicineSt.LouisMissouri Department of Medicine University of CambridgeCambridgeUnited Kingdom Cambridge University Hospitals NHS Foundation Trust CambridgeUnited Kingdom Queen's Medical Research Institute University of EdinburghEdinburghUnited Kingdom Imanova Ltd. London y United Kingdom Institute of Nuclear Medicine University College LondonLondonUnited Kingdom Department of Medicine Imperial College LondonLondonUnited Kingdom Medical Image Analysis Consultant LondonUnited Kingdom Clinical Discovery Respiratory Therapy Area UnitGlaxoSmithKline R&DKing of PrussiaPennsylvania University Hospitals Coventry and Warwickshire CoventryUnited Kingdom Derby Teaching Hospitals NHS Foundation Trust DerbyUnited Kingdom Worldwide Research and Development PfizerInc.CambridgeMassachusetts Experimental Medicine Imaging GlaxoSmithKlineStevenageUnited Kingdom

数百万人受呼吸系统疾病的影响,导致巨大的全球性健康困扰。由于目前对导致呼吸系统疾病发展和进展的潜在机制认识不足,治疗选择仍然有限。为克服此局限和理解相关分子变化,将无创影像技术如PET和SPECT用于探索生物标志物,其中18F-脱氧... 详细信息

数百万人受呼吸系统疾病的影响,导致巨大的全球性健康困扰。由于目前对导致呼吸系统疾病发展和进展的潜在机制认识不足,治疗选择仍然有限。为克服此局限和理解相关分子变化,将无创影像技术如PET和SPECT用于探索生物标志物,其中18F-脱氧葡萄糖(FDG)PET显像的研究最多。由于肺内组织、气体、血液和水的构成比变异,定量分析肺的分子影像数据仍具挑战性。这些成分的比例随着肺部疾病的不同而不同,因此有不同的定量分析方法来显示这种变化,但迄今为止还没有开发出对数据标准化的方法。该文回顾了肺部疾病中18F-FDG PET定量分析方法的数据,聚焦于解释肺内成分变化的方法,解读衍生参数。分析的疾病包括急性呼吸窘迫综合征、慢性阻塞性肺疾病、肺间质性疾病如特发性肺纤维化。基于对既往文献、进行中的研究以及作者间讨论的回顾,作者提出了建议性的注意事项,以协助解读从这些方法及未来研究设计中衍生的参数。

关键词：肺肺部炎症分子成像正电子发射计算机断层显像

GRADE指南：Ⅰ.导论--GRADE证据概要表和结果总结表

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中国循证医学杂志 2011年第4期11卷 437-445页

作者： Gordon Guyatt andrew D.Oxman Elie Akl Regina Kunz gunn Vist jan Brozek Susan Norris Yngve Falck-Ytter Paul Glasziou Hans deBeer Roman jaeschke David Rind joerg Meerpohl Philipp Dahm Holger j.Schünemann GRADE工作组李幼平杨晓妍蒋兰慧沈建通

本文是GRADE(Grading of Recommendations Assessment,Development,and Evaluation)系列文章的导论。该系列文章为使用GRADE系统提供指导,介绍如何将该系统用于系统评价、卫生技术评估(HTAs)及临床实践指南中备选方案的证据质量评价和... 详细信息

本文是GRADE(Grading of Recommendations Assessment,Development,and Evaluation)系列文章的导论。该系列文章为使用GRADE系统提供指导,介绍如何将该系统用于系统评价、卫生技术评估(HTAs)及临床实践指南中备选方案的证据质量评价和推荐强度评级。GRADE方法始于提出一个明晰的问题,包括对所有重要结果的详细说明。证据被收集和汇总后,GRADE提供了明确的标准来评价其质量,包括研究设计、偏倚风险、不精确性、不一致性、间接性及效应量大小。根据支撑证据质量及备选方案带来的预期和非预期结果间的平衡情况,推荐强度以强/弱(或表述为"有条件的"/"任意的")作为特征。GRADE建议用简洁、透明、信息量丰富的结果总结表来汇总证据(以显示证据质量及每一重要结果的相对效应量和绝对效应量),和(或)以证据概要表形式额外提供证据质量评价理由的详细信息。本系列的后续文章涉及如何采用GRADE方法明确构建问题、评价证据质量及形成推荐意见。

关键词： GRADE 系统评价临床实践指南卫生技术评估证据质量推荐强度

Treatment-Plan Comparison of Three Advanced Radiation Treatment Modalities for Fractionated Stereotactic Radiotherapy to the Head and Neck

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International journal of Medical Physics, Clinical Engineering and Radiation Oncology 2019年第2期8卷 106-120页

作者： He Wang james N. Yang Xiaodong Zhang jing Li Steven j. Frank Zhongxiang Zhao Dershan Luo Xiaorong Zhu Congjun Wang Samuel Tung Adam S. Garden David I. Rosenthal Clifton David Fuller Gary Brandon gunn Amol j. Ghia jay P. Reddy Shaan M. Raza Franco De Monte Mark S. Chambers Paul D. Brown Shirley Su jack Phan Department of Radiation Physics The University of Texas MD Anderson Cancer Center Houston TX USA Department of Radiation Oncology The University of Texas MD Anderson Cancer Center Houston TX USA Department of Neurosurgery The University of Texas MD Anderson Cancer Center Houston TX USA Department of Oncologic Dentistry Prosthodontics Thoracic/Head &Neck Surgery The University of Texas MD Anderson Cancer Center Houston TX USA Department of Radiation Oncology The Mayo Clinic Rochester MN USA

Purpose: Fractionated stereotactic radiosurgery (FSRS) can be given with at least three modalities: Gamma Knife, with the noninvasive frameless extend system (GKE);linear accelerator-based volumetric modulated arc therapy (VMAT);and intensity-modulated proton therapy (IMPT). We extracted treatment plans for patients who had received FSRS with GKE for recurrent skull base or intracranial tumors, created corresponding plans for VMAT and IMPT, and compared the quality of the three sets of plans. Methods and materials: Plans were extracted for 9 patients with recurrent malignant skull-base tumors (n = 6) or large intracranial tumors (n = 3) who had received FSRS with GKE (median dose 24 Gy in 3 fractions) in 2013 through 2015. Plans for VMAT were generated with a TrueBeam STx LINAC machine using 6-MV photons, and plans for IMPT were generated with multi-field optimization. The optimized VMAT and IMPT plans were normalized to achieve the best possible target coverage while meeting the same dose-volume constraints on organs at risk (OARs) as the GKE plans. Plans were evaluated on the basis of target coverage, conformity index, homogeneity index, gradient index, and treatment efficiency. Results: The median target volume was 10.2 cm3 (range 1.9 - 33.8 cm3). The VMAT and IMPT plans met all OAR constraints, and target coverage and conformity were comparable among all plans. VMAT and IMPT plans showed significantly better target uniformity and treatment delivery efficiency (P P Conclusion: FSRS for skull base and large intracranial lesions delivered by VMAT and IMPT can achieve comparable target coverage, conformity, and sparing of critical structure as the GKE while providing superior target uniformity and treatment delivery efficiency. The GKE had superior high-dose gradients outside the target and thus better protected surrounding normal structures.

关键词： Gamma Knife Extend System Stereotactic Radiosurgery Volumetric Modulated Arc Therapy Intensity-Modulated Proton Therapy Spot Scanning Proton Therapy

GRADE指南：Ⅳ.证据质量分级--研究的局限性(偏倚风险)

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中国循证医学杂志 2011年第4期11卷 456-463页

作者： Gordon H.Guyatt andrew D.Oxman gunn Vist Regina Kunz jan Brozek Pablo Alonso-Coello Victor Montori Elie A.Akl Ben Djulbegovic Yngve Falck-Ytter Susan L.Norris john W.Williams jr. David Atkins joerg Meerpohl Holger j.Schünemann GRADE工作组李幼平杨晓妍李鸿浩李玲

在GRADE方法中,若多数相关证据来自高偏倚风险的研究,则起初被定为高质量证据的随机试验和低质量证据的观察性研究均有可能被降低质量等级。随机试验已确定的局限性包括:未进行分配隐藏、未实施盲法、未报告失访情况及未恰当考虑意向性... 详细信息

在GRADE方法中,若多数相关证据来自高偏倚风险的研究,则起初被定为高质量证据的随机试验和低质量证据的观察性研究均有可能被降低质量等级。随机试验已确定的局限性包括:未进行分配隐藏、未实施盲法、未报告失访情况及未恰当考虑意向性治疗原则。最近提出的局限性包括:因明显获益而早期终止试验和基于结果选择性报告结局。观察性研究的主要局限性包括使用不合适的对照及未能充分调整预后的不平衡。偏倚风险可因不同结果而异(如全死因死亡率的失访远少于生命质量的失访),许多系统评价都容易忽略这一点。在决定是否因偏倚风险而降低质量等级时,不管是随机试验还是观察性研究,作者不应采用对各个研究取平均值的方法。相反,对任何单个结果,当同时存在高、低偏倚风险的研究时,则应考虑只纳入较低偏倚风险的研究。

关键词： GRADE 证据质量偏倚风险估计值的可信度盲法分配隐藏

GRADE指南：Ⅴ.证据质量评价--发表偏倚

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中国循证医学杂志 2011年第12期11卷 1430-1434页

作者： Gordon H.Guyatt andrew D.Oxman Victor Montori gunn Vist Regina Kunz jan Brozek Pablo Alonso-Coello Ben Djulbegovic David Atkins Yngve Falck-Ytter john W.Williams jr. joerg Meerpohl Susan L.Norris Elie A.Akl Holger j.Schünemann 代表GRADE工作组李幼平王莉钟大可蒋兰慧机构不详

GRADE方法中,随机试验起评即为高质量证据,观察性研究起评即为低质量证据;但若证据本身存在高发表偏倚风险,则两者证据质量级别都应降低。即使最佳证据汇总表纳入的各项研究仅有低发表偏倚风险,发表偏倚仍会极大高估效应值。当可得证据... 详细信息

GRADE方法中,随机试验起评即为高质量证据,观察性研究起评即为低质量证据;但若证据本身存在高发表偏倚风险,则两者证据质量级别都应降低。即使最佳证据汇总表纳入的各项研究仅有低发表偏倚风险,发表偏倚仍会极大高估效应值。当可得证据来自小样本研究、且多数由厂商资助时,作者应怀疑存在发表偏倚。若干基于检验数据类型的方法可用于评价发表偏倚,其中最常用的为漏斗图,但这些方法都有较大局限。发表偏倚可能较常见,必须特别关注早期结果、对样本量与事件数都很小的早期试验结果尤需小心。

关键词： GRADE 证据质量发表偏倚漏斗图利益冲突制药业

选择性头部降温在新生儿脑病后全身轻度低温中应用的多中心随机试验

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世界核心医学期刊文摘（神经病学分册） 2005年第8期1卷 1-1页

作者： Gluckman P.D. Wyatt j.S. Azzopardi D. A. j. gunn 郭俊 Department of Physiology Fac. of Medicine and Health Science Private Bag 92019 AucklandNew Zealand Dr.

Background: Cerebral hypothermia can improve outcome of experimental perinatal hypoxia-ischaemia. We did a multicentre randomised controlled trial to find ou t if delayed head cooling can improve neurodevelopmental outcome in babies with neonatal ***: 234 term infants with moderate to severe neonat al encephalopathy and abnormal amplitude integrated electroencephalography (aEEG ) were randomly assigned to either head cooling for 72 h, within 6 h of birth, w ith rectal temperature maintained at 34-35°C (n=116), or conventional care (n= 118). Primary outcome was death or severe disability at 18 months. Analysis was by intention to treat. We examined in two predefined subgroup analyses the effec t of hypothermia in babies with the most severe aEEG changes before randomisatio n -ie, severe loss of background amplitude, and seizures-and those with less s evere changes. Findings: In 16 babies, follow-up data were not available. Thus in 218 infants (93%), 73/110 (66%) allocated conventional care and 59/108 (55 %) assigned head cooling died or had severe disability at 18 months (odds ratio 0.61; 95%CI 0.34-1.09, p=0.1). After adjustment for the severity of aEEG chan ges with a logistic regression model, the odds ratio for hypothermia treatment w as 0.57 (0.32-1.01, p=0.05). No difference was noted in the frequency of clinic ally important complications. Predefined subgroup analysis suggested that head c ooling had no effect in infants with the most severe aEEG changes (n=46, 1.8; 0. 49-6.4, p=0.51), but was beneficial in infants with less severe aEEG changes (n =172, 0.42; 0.22-0.80, p=0.009). Interpretation: These data suggest that althou gh induced head cooling is not protective in a mixed population of infants with neonatal encephalopathy, it could safely improve survival without severe neurode velopmental disability in infants with less severe aEEG changes.

关键词：脑病温中随机试验失能随机对照试验随机化延迟性围生期预后指标低温治疗

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局灶性癫痫全脑T2图证实存在潜在的异常

世界核心医学期刊文摘（神经病学分册） 2005年第6期1卷 45-45页

作者： Rugg- gunn F.j. Boulby P.A. Symms M.R. j.S. Duncan 姚庆和 National Society for Epilepsy Gerrards Cross Bucks SL9 0RJ United Kingdom Prof.

Objectives: To examine the cerebral structure of 14 patients with partial seizures and acquired lesions, 20 patients with malformations of cortical development (MCDs), and 45 patients with partial seizures and normal conventional MRI using whole- brain T2 mapping and statistical parametric mapping (SPM). Methods: T2 maps were calculated, and individual patients were compared with a group of 30 control subjects using SPM. Results: T2 mapping and objective voxel- by- voxel statistical comparison identified regions of increased T2 signal in all 14 patients with acquired nonprogressive cerebral lesions and partial seizures. In all of these, the areas of increased T2 signal concurred with abnormalities identified on visual inspection of conventional MRI. In 18 of 20 patients with MCDs, SPM detected regions of increased T2 signal, all of which corresponded to abnormalities identified on visual inspection of conventional MRI. In addition, in both groups, there were areas that were normal on conventional imaging, which demonstrated abnormal T2 signal. Voxel- by- voxel statistical analysis identified increased T2 signal in 23 of the 45 patients with cryptogenic focal epilepsy. In 20 of these, the areas of increased T2 signal concurred with epileptiform EEG abnormality and clinical seizure semiology. Group analysis of MRI- negative patients with electroclinical seizure onset localizing to the left and right temporal and left and right frontal regions revealed increased T2 signal within the white matter of each respective lobe. Conclusions: T2 mapping analyzed using statistical parametric mapping was sensitive in patients with malformations of cortical development and acquired cerebral damage. Increased T2 signal in individual and grouped MRInegative patients suggests that minor structural abnormalities exist in occult epileptogenic cerebral lesions.

关键词：局灶性癫痫 T2 信号增强临床发作非进展性脑损伤体素右颞叶谱分析法大脑结构

THz Oscillations in a GaN Based Planar Nano-Device

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journal of Computer and Communications 2013年第7期1卷 50-53页

作者： K. Y. Xu Y. N. Wang Z. N. Wang j. W. Xiong G. Wang Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou China 2State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou China.

gunn oscillations in a GaN based planar nano-device have been studied by ensemble Monte Carlo (EMC) method. Simulation results show that when the channel length of the device reduces to 450 nm, THz oscillations (about 0.3 THz) can be obtained. Also the phase of the oscillations can be controlled by the initial conditions that excite the gunn domains. Moreover, through adjusting the phase difference between the oscillations in a double-channels device, which attained by parallel connecting two single-channel devices, the frequency of the device shifts from 0.3 THz to 0.6 THz. This phenomenon remains in devices with shorter channel-length, unless the channel-length is too short to support gunn oscillations. The possible underlying mechanisms are also discussed.

关键词： THz Oscillation gunn Monte Carlo GaN Planar Nanodevice