经食管超声心动图双平面法测量主动脉瓣环径

目的 探讨经食管超声心动图双平面法测量经导管主动脉瓣植入术（TAVI）患者主动脉瓣环径的可行性。方法 对24例拟行TAVI的患者,术前分别采用经胸超声心动图（2D-TTE）、经食管超声心动图（2D-TEE）、三维经食管超声心动图（3D-TEE）及经食管超声心动图双平面法（Bip-TEE）测量主动脉瓣环径。比较4种方法测量的差异以及3D-TEE测量值与另外3种方法测量值的相关性。结果 2D-TTE、2D-TEE、Bip-TEE与3D-TEE所测的主动脉瓣环径分别为（22.02±2.21）mm、（23.34±2.34）mm、（23.89±2.37）mm;（24.21±2.78）mm,4组测量值总体差异有统计学意义（F=3.88,P=0.01）。3D-TEE与2D-TEE、Bip-TEE所测量主动脉瓣环径差异无统计学意义（P均>0.05）,2D-TEE与Bip-TEE测量值差异无统计学意义（P>0.05）。2D-TTE与3D-TEE、2D-TEE、Bip-TEE所测的主动脉瓣环径比较差异均有统计学意义（P均<0.05）。3D-TEE所测的主动脉瓣环径与2D-TTE、2D-TEE、Bip-TEE测值均呈正相关（r=0.79、0.88、0.94,P均<0.05）。结论 经食管超声心动图双平面法可用于准确测量主动脉瓣环径,从而为TAVI提供可靠的瓣膜型号选择依据。     

胃肠超声造影联合超声内镜对老年胃癌患者T分期的价值研究

目的 探讨胃肠超声造影联合超声内镜在老年胃癌患者T分期中的应用价值。方法 回顾性分析2016年1月－2021年12月在该院诊疗的102例老年胃癌患者的临床资料,年龄60～78岁,术前1周均行胃肠超声造影和超声内镜。观察不同检查方法术前的影像学诊断资料,以术后病理T分期作为诊断金标准,比较胃肠超声造影、超声内镜和胃肠超声造影联合超声内镜在老年胃癌患者T分期中的临床应用价值。结果 胃肠超声造影对老年胃癌患者T分期总体诊断准确率为70.59%,超声内镜总体诊断准确率为73.53%,胃肠超声造影联合超声内镜总体诊断准确率为85.29%。胃肠超声造影联合超声内镜在老年胃癌患者T分期中,总体诊断准确率明显高于单独胃肠超声造影和超声内镜（P < 0.05）;对于T₁期和T₂期老年胃癌患者,联合检查诊断准确率略高于超声内镜,高于胃肠超声造影,但差异均无统计学意义（P > 0.05）;对于T₃期老年胃癌患者,胃肠超声造影与超声内镜诊断准确率相当,略低于联合检查,差异均无统计学意义（P > 0.05）;对于T₄期老年胃癌患者,联合检查诊断准确率略高于胃肠超声造影（P > 0.05）,而明显高于超声内镜（P < 0.05）。结论 胃肠超声造影联合超声内镜,能明显提高老年胃癌患者T分期总体诊断准确率;对于T₁期和T₂期老年胃癌患者,可优先选择超声内镜;对于T₃期和T₄期老年胃癌患者,可选择联合检查,以弥补单一检查的不足,从而为临床手术方案的选择,提供更精确的指导。     

比较MR弹性成像及动态增强成像评价肝硬化食管胃底静脉曲张

目的 比较MR弹性成像（MRE）及动态增强成像（DCE-MRI）诊断肝硬化食管胃底静脉曲张（GEV）的价值。方法 收集接受MRE及DCE-MRI检查的肝硬化患者59例,记录血小板计数（PLT）,测量肝弹性值（HS）、脾弹性值（SS）和MR增强视觉分级相关指标;以内镜结果为金标准,采用ROC曲线下面积（AUC）比较相关指标诊断GEV的价值。结果 PLT、HS、SS及MR增强视觉分级与肝硬化GEV分级具有相关性（r_s=-0.317、0.436、0.682、0.703,P均<0.05）。诊断有无GEV时,SS的AUC略高于MR增强视觉分级、HS、PLT （AUC分别为0.880、0.795、0.744、0.635）,其中SS与PLT的AUC差异有统计学意义（P=0.002）;诊断中重度GEV时,MR增强视觉分级的AUC略高于SS、HS、PLT （AUC分别为0.893、0.816、0.713、0.665）,其中MR增强视觉分级与HS、PLT的AUC差异有统计学意义（P=0.018、0.002）。联合SS及MR增强视觉分级,鉴别诊断有无GEV及中重度GEV的敏感度分别为94.16%、96.83%。结论 MRE可有效预测GEV及其严重程度,与DCE-MRI效果相当。     

经食管超声心动图在牛心包主动脉瓣置换术中的应用

目的 评价术中经食管超声心动图（IOTEE）在牛心包主动脉瓣置换术中的应用价值。方法 回顾性分析拟施行牛心包主动脉瓣置换术的106例患者,分别于体外循环前采用IOTEE测量和术中解剖测量主动脉瓣环径、主动脉窦部和主动脉窦管交界直径、主动脉瓣叶有效高度（eH）。结果 术前拟行牛心包主动脉瓣置换术106例患者,其中8例经IOTEE术前补充诊断后修改手术方式被排除。余98例均接受牛心包主动脉瓣置换术。98例IOTEE首要诊断与手术诊断符合率为100%,5例（5/98,5.10%）IOTEE次要诊断与手术诊断不相符。98例患者体外循环前IOTEE提示瓣叶数目与术中探查符合率100%、瓣叶穿孔符合率80.00%,瓣叶赘生物符合率85.71%、老年退行性钙化符合率100%、风湿性病变符合率100%。体外循环前IOTEE测量的主动脉瓣环径、主动脉窦部和主动脉窦管交界直径、eH与术中实际测量结果相关性良好（r均>0.8,P均<0.05）。结论 IOTEE对于评估牛心包主动脉瓣置换术的可行性、指导选择手术方案和预估手术效果有重要意义。     

实时三维经食管超声心动图在经皮左心耳封堵术治疗非瓣膜病性心房颤动患者中的应用价值

目的 探讨实时三维经食管超声心动图（RT-3D-TEE）在经皮左心耳封堵术（PLAATO）治疗非瓣膜病性心房颤动中的应用价值。方法 对62例接受PLAATO的非瓣膜病性心房颤动患者行二维经食管超声心动图（2D-TEE）、RT-3D-TEE和心血管造影（CAG）检查,分别测量左心耳口最大径、左心耳口最小径、左心耳口深度,并比较三者的差异。以RT-3D-TEE测量的左心耳口最大径测量值为依据,选择适当封堵器型号,并在RT-3D-TEE、CAG引导下进行左心耳封堵术。术后进行随访。结果 62例均封堵成功,成功率为100%,封堵压缩率为（19.78±6.92）%;术中、术后随访期内均未发生严重并发症。2D-TEE、RT-3D-TEE及CAG测量的左心耳口最大径总体差异有统计学意义（P=0.029）,RT-3D-TEE测值高于2D-TEE而低于CAG;三者测量的左心耳口最小径和左心耳深度总体差异均无统计学意义（P均>0.05）。CAG、RT-3D-TEE和2D-TEE测量的左心耳口最大径与封堵器尺寸均呈正相关（r=0.925、0.841、0.716,P均≤ 0.001）。结论 RT-3D-TEE可用于PLAATO治疗非瓣膜病性心房颤动术前筛选、术中引导和术后随访,能准确观察左心耳口形态并评估封堵效果。     

三维经食管超声心动图与其他影像技术指导左心耳封堵术的对比

目的 探讨三维经食管超声心动图（3D-TEE）和2D-TEE、CTA和术中X线造影在左心耳（LAA）形态、大小评估及指导封堵器型号选择方面的价值。方法 对43例拟行LAA封堵术的心房颤动患者行TEE,清晰显示LAA并于0°、45°、90°和135°分别测量其开口最大径和最大深度值;于LAA显示最清晰切面启动3D-ROOM模式测量开口最大径、最小径,并将其与2D-TEE、CTA和X线造影的检查结果进行对比。结果 3D-TEE测量LAA开口最大径与2D-TEE、术中X线造影测值差异无统计学意义（P均>0.05）,CTA测量LAA开口最大径明显大于3D-TEE、2D-TEE和X线造影测值（P<0.01）;2D-TEE于90°和135°测量LAA最大深度值与CTA测值差异有统计学意义（P均<0.05）,与术中X线造影比较,仅在135°时差异有统计学意义（P<0.01）。3D-TEE测量LAA开口最大径与2D-TEE各角度、CTA和X线造影测值呈明显正相关（r=0.70~0.77、0.57、0.58,P均<0.01）;2D-TEE各角度测量LAA开口最大径与CTA、X线造影测值均存在相关性（r=0.57~0.71,0.45~0.51;P均<0.01）;3D-TEE、2D-TEE、CTA及X线造影LAA开口最大径与封堵器大小均呈明显正相关且（r=0.93、0.70~0.77、0.57、0.47,P均<0.01）。结论 3D-TEE与2D-TEE、CTA和X线造影相比,3D-TEE对于封堵器大小的选择更具指导性。     

埃布斯坦畸形患者右心功能参数:超声心动图与MRI评估结果的相关性

目的 分析超声心动图与心脏MRI所获埃布斯坦畸形（EA）患者右心功能参数的相关性。方法 回顾性分析经手术证实的32例EA患者的经胸超声心动图及心脏MRI资料,观察超声心动图所获心腔大小、右心功能及应变参数与MRI所测功能右心室（fRV）射血分数（EF）的相关性。结果 MRI所测 32例EA的 fRV-EF为（23.20±7.61）%。超声心动图所获32例EA右心功能参数中,fRV面积变化分数（fRV-FAC）（r=0.347,P=0.015）与MRI fRV-EF呈低度、fRV整体纵向应变（GLS）（r=0.801,P<0.001）与MRI fRV-EF呈高度正相关,房化右心室（aRV）面积/fRV面积与MRI fRV-EF呈高度负相关（r=－0.730,P=0.007）,aRV面积/左心室面积（r=－0.450,P=0.042）及右心室前后径（r=－0.650,P=0.022）与MRI fRV-EF均呈中度负相关,左心室偏心指数（r=－0.347,P=0.049）、扩展格拉斯哥预后评分（r=－0.336,P=0.024）均与MRI fRV-EF呈低度负相关。结论 超声心动图与MRI所获EA患者右心功能参数存在相关性;其中,fRV GLS及aRV面积/fRV面积均与MRI fRV-EF呈高度正相关,对于评估EA患者右心功能具有重要价值。     

基于多层螺旋CT简易评分模型鉴别局灶型食管癌与食管平滑肌瘤

目的 观察多层螺旋CT（MSCT）简易评分模型鉴别局灶型食管癌与食管平滑肌瘤的效能。方法 对46例局灶型食管癌和21例食管平滑肌瘤患者术前均行胸部增强CT检查,观察二者病变位置、密度、大小、病灶MPR最长径/轴位最厚厚度比值、强化程度及方式、瘤-空气界面、瘤周脂肪间隙及肿大淋巴结;对存在差异的CT征象进行Logistic回归分析,建立简易评分模型,采用受试者工作特征曲线（ROC）其鉴别诊断效能。结果 二者肿瘤MPR最长径/轴位最大截面厚度比值[优势比（OR）=0.154,95% CI（0.033,0.722））、肿瘤增强CT值[OR=0.928,95% CI（0.866,0.994）]及瘤-空气界面[OR=0.028,95% CI（0.004,0.184）]存在显著差异（P均<0.05）。据此建立简易评分模型,肿瘤增强CT值>65.5 HU赋值1分,肿瘤MPR最长径/轴位最大截面厚度比值>1.61为2分,瘤-空气界面不光滑为4分,以2.5分为最佳阈值,≥ 2.5分诊断为局灶型食管癌,简易评分模型曲线下面积（AUC）为0.945[95% CI（0.891,0.999）],其鉴别诊断效能优于单一特征（P<0.05）。结论 MSCT简易评分模型有助于鉴别局灶型食管癌与食管平滑肌瘤,可显著提高诊断效能。     

XPLANE技术评价经皮介入封堵房间隔缺损前后右心室功能

目的 探讨采用XPLANE技术测量右心室纵向缩短分数（LSF）评估经皮介入封堵（PI）房间隔缺损（ASD）前后右心室功能变化的应用价值，分析及其影响因素。方法 收集68例经超声检查诊断ASD并接受PI患者，分别于术前及术后1、3个月行超声心动图检查，采用XPLANE技术测量并比较其二腔心切面（LSF_AP2）和四腔心切面（LSF_AP4）图像LSF及其均值（LSF_APM）、三尖瓣环收缩期位移（TAPSE）、肺动脉高压（PH）分级、右心室与左心室舒张末期内径比（RVEDD/LVEDD）分级的差异；分析LSF_AP2、LSF_AP4、LSF_APM与TAPSE的相关性及LSF_APM的影响因素。结果 术后1、3个月RVEDD/LVEDD（H=76.07、77.74）及PH分级（H=42.02、49.83）均较术前降低（P均<0.05）。3个时间点之间右心室LSF_AP2、LSF_AP4、LSF_APM及TAPSE差异均有统计学意义（F=6.11、3.18、8.35、20.28，P均<0.05）；术前与术后3个月LSF_AP4、LSF_APM差异无统计学意义（P均>0.05），LSF_AP2、LSF_AP4、LSF_APM及TAPSE两两比较差异均有统计学意义（P均<0.05）。PI前后LSF参数均与TAPSE呈正相关（P均<0.05）。年龄、术前PH分级为LSF_APM的共同影响因素。结论 利用XPLANE技术可有效观察ASD患者PI前后右心室功能变化。PI术后ASD患者右心室形态及功能均获改善，且术前及术后LSF参数与TAPSE变化趋势基本一致。年龄和术前PH分级为ASD患者右心功能的影响因素。     

经食管与经胸超声心动图造影诊断卵圆孔未闭及右向左分流

目的 对比经食管超声心动图造影（cTEE）与经胸超声心动图造影（cTTE）诊断卵圆孔未闭（PFO）及右向左分流（RLS）的价值。方法 回顾性分析117例因偏头痛或隐源性卒中就诊的患者,均依次接受TTE、cTTE、TEE及cTEE检查;比较cTTE与cTEE诊断PFO的敏感度、特异度及对RLS分级的差异,观察二者诊断价值。结果 TEE联合cTEE共检出89例（76.07%,89/117）PFO;TTE、cTTE、TEE及cTEE分别检出18例（20.22%,18/89）、80例（89.89%,80/89）、75例（84.27%,75/89）及88例（98.88%,88/89）。cTTE存在9例（10.11%,9/89）假阴性、7例（25.00%,7/28）假阳性;cTEE存在1例（1.12%,1/89）假阴性,无假阳性病例。cTEE诊断PFO的敏感度（98.88%）及特异度（100%）均高于cTTE（89.89%、75.00%;χ²=6.125、5.143,P=0.008、0.016）;cTEE的PFO-RLS分级结果总体低于cTTE（Z=-3.464,P=0.001）。结论 cTEE诊断PFO的敏感度及特异度均高于cTTE,而其PFO-RLS分级总体低于cTTE。     

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.