CT能谱成像在小肠克恩罗恩病活动度评估中的价值

目的:探讨CT能谱成像定量分析在小肠克罗恩病活动度评估中的价值。方法:回顾性分析我院2015年8月至2016年9月行CT能谱成像检查,且经病理证实的小肠克罗恩病患者54例,将其分为活动期组(34例)和缓解期组(20例),对其活动期与缓解期的肠壁动脉期(aterial phase,AP)及门脉期(portal phase,PP)标化碘浓度(normalized iodine concentration,nIc)、标化水浓度(normalized water concentration,nWc)、能谱曲线斜率进行比较,并计算和绘制上述有统计学差异的变量的受试者工作特征曲线。结果:CT能谱成像中,小肠克罗恩病患者活动期肠壁AP及PP的n Ic值分别为(0.228±0.100) g/L、(0.530±0.097) g/L,均高于缓解期[AP及PP的nIc分别为(0.097±0.045) g/L、(0.252±0.063) g/L](P0.05);而活动期的肠壁PP的nWc值为(0.232±0.068) g/L,高于缓解期肠壁[(0.009±0.013) g/L](P0.05);活动期的肠壁AP、PP能谱曲线的斜率分别为(2.749±1.051)和(3.638±0.724),均高于缓解期[AP、PP分别为(1.069±0.467)和(1.653±0.687)](P0.05);CT能谱成像AP、PP的nIc鉴别小肠克罗恩病活动期与缓解期的受试者工作特征曲线下面积值分别为0.965和0.998;PP的nWc鉴别二者的曲线下面积值为0.726;AP、PP的能谱曲线斜率鉴别二者的曲线下面积值分别为0.964和0.972。结论:CT能谱成像可以定量鉴别克罗恩病的活动期与缓解期,AP和PP的nIc值及能谱曲线斜率是两者鉴别中较优的参数。     

CT能谱成像在壶腹周围癌诊断中的价值研究

目的：探讨宝石CT能谱分析在壶腹周围癌诊断中的价值。方法：回顾性分析30例壶腹周围癌患者（其中包括胰头癌15例,十二指肠乳头癌9例,胆总管下段癌6例）的影像学资料,将结果与手术病理对照。患者均行宝石CT能谱成像双期扫描,获得140 kVp QC图像和70 keV单能量图像,于门静脉期对病灶进行测量分析,记录相关数据,包括不同keV（40～100）水平的CT值、碘－水浓度、有效原子序数及能谱曲线,计算近段（50～100 keV）曲线斜率,并对数据进行统计学分析。结果：门静脉期,在低能量（50～100 keV）水平,胰头癌病灶的CT值明显低于十二指肠乳头癌及胆总管下段癌,而十二指肠乳头癌的CT值又低于胆总管下段癌,在CT能谱曲线上表现为近段斜率之间的差异（胰头癌平均斜率为0.75±0.18,十二指肠乳头癌为1.61±0.39,胆总管下段癌为2.22±0.41）。胰头癌的平均碘浓度（（7.17±0.96） g/L）及有效原子序数（7.92±0.41）均低于十二指肠乳头癌（碘浓度（18.10±1.57） g/L,有效原子序数8.54±0.26）及胆总管下段癌（碘浓度（23.21±3.50） g/L,有效原子序数8.72±0.48）。十二指肠乳头癌的碘浓度明显低于胆总管下段癌,而两者的有效原子序数无显著差异。三者的水浓度亦无显著差异（胰头癌、十二指肠乳头癌、胆总管下段癌的水浓度分别为1 024.64±16.02,1 018.92±12.16,1 013.36±12.86）。结论：不同病理类型的壶腹周围癌具有各自不同的能谱特征,CT能谱成像对壶腹周围癌的鉴别诊断有一定价值。     

能谱CT评估颈动脉粥样硬化非钙化斑块成分

目的应用能谱CT研究颈动脉粥样硬化(AS)非钙化斑块成分及稳定性。方法收集35例颈动脉狭窄患者,行颈动脉能谱CTA检查,应用能谱分析软件,分析非钙化斑块成分,对不同成分的能谱CT特征性参数进行独立样本t检验。结果 35例共检出非钙化斑块65处,其中脂质成分23处,纤维成分33处,血栓样组织9处。脂肪成分、纤维成分、血栓样组织的CT值衰减曲线斜率分别为-3.46±0.62、2.06±0.73、0.32±0.09;有效原子序数分别为3.73±0.88、8.76±0.53、7.60±0.78;碘(脂肪)浓度分别为(-2.62±0.83)g/L、(3.65±0.56)g/L、(1.71±0.74)g/L,差异均有统计学意义(P均<0.05)。结论颈动脉非钙化斑块中的脂质成分、纤维成分及血栓样组织表现出不同的能谱成像特性;能谱CT参数分析可为区分非钙化斑块成分提供量化依据。     

能谱CT定性诊断胸腔积液性质研究

目的应用能谱CT对胸腔积液进行定性分析,为临床制定治疗方案提供参考。方法 50例胸腔积液患者经胸腔穿刺术抽出胸腔积液后,分别行常规生化检查和能谱CT扫描。根据常规生化检查结果,将50例患者分为渗出液组和漏出液组,应用能谱分析软件分析2组常规混合能量CT值、40~140keV单能量CT值、能谱曲线斜率以及漏出液或渗出液中配对基物质浓度值。结果常规生化检查结果确定漏出液22例(漏出液组)和渗出液28例(渗出液组);渗出液组常规混合能量CT值[(19.42±3.97)Hu]高于漏出液组[(13.35±3.26)Hu](P0.05),能谱曲线斜率(0.498)高于漏出液组(0.176)(P0.05);40、50、60、70、80、90、100、110、120、130keV单能量下,渗出液组CT值明显高于漏出液组(P0.05);渗出液组140keV单能量下CT值[(9.82±2.59)Hu]与漏出液组[(6.14±2.51)Hu]组比较差异无统计学意义(P0.05);渗出液组碘(水)[(5.86±1.21)g/L]、钙(水)[(7.93±1.74)g/L]、钙(脂肪)[(26.03±1.54)g/L]浓度值均高于漏出液组[碘(水)(1.81±0.67)g/L、钙(水)(2.62±1.32)g/L、钙(脂肪)(20.23±1.39)g/L](P0.05),水(钙)[(1 000.12±231.5)g/L]和脂肪(钙)[(979.94±1.42)g/L]浓度均低于漏出液组[水(钙)(1 203.52±208.31)g/L、脂肪(钙)(1 182.74±2.17)g/L](P0.05)。结论渗出液与漏出液的能谱CT特征参数有明显差异,能谱CT可在短时间内快速、有效的对胸腔积液进行定性诊断。     

能谱CT对甲状腺乳头状癌的诊断价值

目的探讨能谱CT成像（GSI）技术对于甲状腺乳头状癌（PTC）的诊断价值。方法收集经手术病理证实的32例（共45个结节）甲状腺乳头状癌患者,行甲状腺能谱CT单能模式平扫及增强扫描,测量结节的碘浓度,计算能谱曲线斜率,并与病理结果对照。结果平扫期、动脉期、静脉期甲状腺乳头状癌的碘浓度（100μg/ml）分别为5.77±4.23、10.42±5.78、18.27±5.09;能谱衰减曲线斜率分别为-0.53±0.26、-0.84±0.52、-1.24±0.30。各期乳头状癌组的碘浓度及曲线斜率绝对值均小于良性结节组和正常甲状腺组（P均〈0.05）。32例中有23例出现淋巴结转移,其中18例能谱曲线与原发灶完全一致。结论能谱CT对甲状腺乳头状癌的准确诊断具有重要价值。     

能谱CT鉴别诊断腮腺良恶性肿瘤的价值分析

目的:探讨分析能谱CT鉴别诊断腮腺良恶性肿瘤的应用价值。方法:将50例腮腺肿瘤患者纳入本次研究工作,均进行能谱CT检查,并对检查结果进行分析探讨。结果:共发现有58个病灶(46个良性病灶及12个恶性病灶);腮腺良恶性肿瘤的CT征象有明显差异(P0.05);平扫期及静脉期腮腺良恶性肿瘤的碘浓度值、能谱曲线斜率及有效原子序数均无明显差异(P0.05);动脉期腮腺良恶性肿瘤的碘浓度值、能谱曲线斜率及有效原子序数有明显差异(P0.05)。依据动脉期碘浓度阀值(18.90*100ug/m)进行诊断腮腺恶性肿瘤,结果显示敏感度为81.7%、特异性为79.5%。结论:应用能谱CT鉴别诊断腮腺良恶性肿瘤的临床价值显著,可以起到有效鉴别作用,值得临床加强推广及应用。     

能谱CT综合分析对良恶性浆膜腔积液的鉴别价值

探讨能谱CT综合分析对良恶性浆膜腔积液的鉴别价值。方法:回顾分析2012年1月—2012年10月我院行能谱CT扫描并经组织学或生化检查证实的浆膜腔积液患者85例,其中良性浆膜腔积液14例、恶性浆膜腔积液71例。应用能谱综合分析平台,分别测量和计算各浆膜腔积液的常规混合能量CT值、不同单能量keV(40~140 keV)的CT值、有效原子序数及其分布峰值、脂(水)浓度、水(碘)浓度、水(钙)浓度、能谱曲线斜率并做相应统计分析,统计比较良恶性积液的曲线类型。结果:混合能量和单能量70~120 keV下CT值两组差异无统计学意义,良恶性积液在单能低keV(40~60 keV)CT值有显著的统计学差异,在130~140 keV两组CT值差异有统计学意义,良性积液有效原子序数及其分布峰值均高于恶性(P<0.01),恶性组脂(水)、水(碘)、水(钙)浓度均高于良性组(P<0.01),良性曲线斜率大于恶性(P<0.01),良恶性积液具有不同曲线类型(P<0.01)。结论:能谱CT综合分析平台给良恶性浆膜腔积液鉴别提供了一个多参数的方法。     

能谱CT鉴别肾透明细胞癌和乏脂型肾血管平滑肌脂肪瘤的应用

目的探讨能谱CT成像对鉴别肾透明细胞癌和乏脂型肾血管平滑肌脂肪瘤的应用价值。方法回顾性分析经病理证实的肾透明细胞癌22例和肾血管平滑肌脂肪瘤14例能谱CT资料。通过AW 4.6工作站GSI(gemstone spectral imaging)Viewer软件测量病灶直径、平扫有效原子序数、平扫脂基值、皮质期碘浓度、皮质期CT值,髓质期碘浓度、髓质期CT值、皮质期主动脉的碘浓度、髓质期主动脉碘浓度,然后计算皮质期标准化碘浓度(normalized iodine concentration,NIC)、髓质期NIC、皮髓两期NIC差值。采用两样本t检验分析上述参数,并用ROC曲线分析各定量参数的诊断效能。结果肾透明细胞癌的有效原子序数、脂基值、皮质期的NIC浓度、髓质期的NIC浓度、皮髓两期NIC浓度的差值、皮质期CT值、髓质期CT值分别为7.57±0.12、-142.77±32.41 g/L、0.64±0.13、0.49±0.14、0.15±0.16、113.97±13.92 HU、94.34±10.53HU;乏脂型肾血管平滑肌脂肪瘤的分别为7.73±0.10、-101.94±11.14 g/L、0.5±0.82、0.58±0.10、-0.09±0.11、100.36±17.56HU、103.60±14.51 HU,差异均有统计学意义(P0.05)。ROC曲线分析示脂基值和皮髓两期NIC差值对鉴别肾透明细胞癌和乏脂型肾血管平滑肌脂肪瘤具有较高的敏感度(85.7%、77.3%)和特异度(86.4%、100%),且曲线下面积最大,均为0.891。结论能谱CT多种参数对鉴别肾透明细胞癌和乏脂型肾血管平滑肌脂肪瘤有一定价值,其中脂基值和皮髓两期NIC差值的诊断效能最高。     

双源CT能谱成像定性评估胃癌转移淋巴结

目的 探讨双源CT能谱成像定性评估胃癌转移淋巴结的价值。方法 收集病理确诊为胃癌的67例患者资料,术前均接受双源CT腹部平扫和能谱双期增强扫描,测量并记录淋巴结长径、短径、短长径比、动脉期和静脉期标准化碘浓度,绘制能谱衰减曲线,并计算其斜率。对转移淋巴结和非转移淋巴结间差异有统计学意义的参数绘制ROC曲线,确定诊断胃癌转移淋巴结的阈值、敏感度和特异度。结果 胃癌转移淋巴结与非转移淋巴结的短径、短长径比、动脉期和静脉期标准化碘浓度差异均有统计学意义（P均<0.05）,ROC曲线下面积分别为0.601（P=0.006）、0.881（P<0.001）、0.865（P<0.001）和0.834（P<0.001）。以短长径比=0.734为阈值,双源CT能谱成像诊断胃癌转移淋巴结的敏感度75.72%、特异度93.64%;以动脉期标准化碘浓度0.223为阈值,敏感度69.81%,特异度91.20%;以静脉期标准化碘浓度0.392为阈值,敏感度78.33%,特异度85.63%。胃癌转移淋巴结与非淋巴结的双期能谱曲线呈下降型,动脉期曲线斜率为6.860时,诊断胃癌转移淋巴结的敏感度为83.24%,特异度为84.72%;静脉期斜率为6.660时,敏感度为64.62%,特异度为97.70%。淋巴结短长径比、动脉期标准化碘浓度及能谱曲线斜率联合诊断胃癌转移淋巴结的敏感度和特异度分别为97.34%和87.83%;淋巴结短长径比、静脉期标准化碘浓度及能谱曲线斜率联合诊断诊断胃癌转移淋巴结敏感度80.13%,特异度90.31%。结论 胃癌患者淋巴结短长径比、动静脉期标准化碘浓度、动静脉期斜率是评估其转移性的主要参数;三者联合可明显提高双源CT能谱成像诊断胃癌淋巴结转移的效能。     

能谱CT鉴别诊断肝脏单纯囊肿和单房囊性包虫病

目的 探讨能谱CT在鉴别肝脏单纯囊肿(HC)和肝脏单房囊性包虫(UHCE)的应用价值.方法 回顾性分析39例肝脏单房囊性占位病变患者,其中HC 19例(HC组),UHCE 20例(UHCE组),行平扫和三期增强能谱CT扫描后获得40~140 keV单能图像病灶的CT值、碘(水)浓度、水(碘)浓度、有效原子序数,测量正常肝组织和腹主动脉碘值,计算不同期相标准化碘浓度(NIC)和病灶与周围正常肝组织碘浓度比值(LNR),对两组结果进行统计学分析,并进行ROC曲线分析.结果 HC 40~50 keV平扫、动脉期及延迟期单能量CT值均低于UHCE (P均 <0.05),平扫和增强三期HC的碘(水)浓度低于UHCE(P <0.05),平扫、 动脉期及延迟期HC的有效原子序数低于UHCE(P <0.05);平扫和动脉期HC的NIC高于UHCE(P均 <0.05);HC动脉期水(碘)浓度略低于UHCE(P <0.05);平扫40 keV下鉴别HC和UHCE的敏感度(100%)和特异度最高(75%).结论 能谱CT成像的定量分析对HC和UHCE的鉴别诊断有一定价值.     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.