128层螺旋CT在冠心病诊断中的应用研究

目的研究128层螺旋CT冠脉成像对冠心病的冠状动脉狭窄,特别是细小分支狭窄的临床诊断价值和准确度。方法以传统X线冠状动脉造影(CAG)为金标准,与同期2～7d内行64排128层螺旋CT的图像进行对比研究。结果本研究中CT图像能够满足冠状动脉管腔评价的节段占96.50%,CT图像满足诊断要求的节段中,常规冠状动脉造影共发现中度和中度以上狭窄120节段,其中重度狭窄34节段。本组病例中以CAG作为金指标,显示重度狭窄的敏感度和特异度分别为99.8%和96.6%,阳性预测值和阴性预测值分别为99.8%和96.5%。结论对于达到扫描评价条件的冠脉图像,128层螺旋CT可作为冠心病临床诊断及介入治疗的一种无创筛选方法;能较可靠地排除临床表现不明确的冠心病患者,尤其是评价左主干、左前降支和回旋支的近端准确度非常高。     

多层螺旋CT冠状动脉显像对老年冠心病的诊断评价

目的:评价多层螺旋CT(MSCT)冠状动脉显像对老年冠心病的诊断价值。方法:对2005年3月至2006年3月我院60例临床诊断或可疑冠心病人进行MSCT冠状动脉成像和导管法冠状动造影检查,评价其诊断价值。结果:MSCT能满足影像学评价的冠状动脉节段而言,MSCT显示冠状动脉中度或中度以上狭窄(≥50%)的敏感度和特异度分别为77.5%和97.8%(!2=284.25,P=0.000);显示冠状动脉高度狭窄(≥75%)或完全闭塞的敏感度和特异度分别为80%和99.3%(!2=320.03,P=0.000)。结论:MSCT对显示有临床意义的冠状动脉狭窄(≥50%)具有优良诊断价值。     

多层螺旋CT对冠状动脉桥血管的评价

目的 评价16层螺旋CT在冠状动脉搭桥术后随访中的价值。方法 8例冠状动脉搭桥术后患者行心电门控下16层螺旋CT冠状动脉成像。原始数据传至工作站，进行容积再现(VRT)、最大密度投影(MIP)、曲面重建(CPR)和仿真内窥镜(CTVE)等后处理，观察桥血管位置、管腔通畅情况。结果 在CT图像上，8例患者的12根桥血管均可用于评价，并且未发现明显再狭窄和闭塞。结论 16层螺旋CT可无创性对冠状动脉桥血管进行评价。     

16层螺旋CT冠状动脉重建成像在冠状动脉疾病诊断中的临床应用

目的总结16层螺旋CT冠状动脉(简称冠脉)重建成像在冠状动脉疾病诊断中的临床意义。方法回顾分析60例患者所做的16层螺旋CT冠脉重建图像。采用回顾性心电门控技术、分段(Segment)数据采集方式和选择75%的时间相位窗,对扫描数据进行容积再现技术(VRT)、最大密度投影(MIP)、多平面重建(MPR)、曲面重建(CPR)、CT仿真内镜(CTVE)等图像后处理。结果60例患者2例冠脉成像不良,不能用于影像诊断;33例冠脉成像未提示明确异常;21例冠脉成像提示有不同程度的冠脉病变;4例4枚支架有两枚支架显示通畅,1枚支架疑有软斑块形成,1枚支架阻塞。结论16层螺旋CT冠脉重建成像能较好地显示冠脉管腔II～III度狭窄情况及冠脉斑块形成情况,较好地评估冠脉支架植入情况,在早期发现和诊断冠心病及对高危人群进行普查方面有较高的临床应用价值,是一种较有效的无创性冠脉疾病检查诊断方法。     

分析64层螺旋CT诊断不同程度冠状动脉狭窄的临床应用

目的:分析64层螺旋CT诊断不同程度冠状动脉狭窄的临床应用。方法:选取2020年9月至2021年4月我院疑似冠状动脉狭窄患者80例，均采用64层螺旋CT和冠状动脉造影诊断，以冠状动脉造影诊断结果为“金标准”,统计64层螺旋CT诊断结果和诊断效能。结果:80例疑似冠状动脉狭窄患者中，冠状动脉造影证实轻度狭窄节段数69个，中度狭窄节段数67个，重度狭窄节段数64个；采用64层螺旋CT诊断出轻度狭窄节段数73个，中度狭窄节段数69个，重度狭窄节段数65个；64层螺旋CT诊断重度冠状动脉狭窄特异度99.12%(334/337)、准确性98.75%(396/401)较轻度冠状动脉狭窄95.78%(318/332)、94.01%(377/401)和中度冠状动脉狭窄96.71%(323/334)、95.01%(381/401)高，差异有统计学意义(P<0.05)。结论:64层螺旋CT在不同程度冠状动脉狭窄诊断中有较高准确性和特异度，临床应用价值高。     

原发性输尿管癌多层螺旋CT及三维重建诊断价值

目的:探讨多层CT及三维重建技术在原发性输尿管癌中的诊断价值。方法:搜集经手术或活检病理证实的原发性输尿管癌16例,均行多层螺旋CT扫描(MSCT),多平面重建(MPR)、曲面重建(CPR)、最大密度投影(MIP)及容积漫游技术(VRT)处理。结果:原发性输尿管癌轴位CT表现为管腔内软组织肿块伴管壁增厚,增强扫描轻-中度强化,增强峰值位于静脉期,MPR和CPR图像均清晰显示肿瘤侵犯的部位、范围、数目及输尿管壁增厚和周围侵犯情况,CPR图像能在一个平面上显示输尿管全程,MIP和VRT图像类似于静脉尿路造影(IVU)。结论:MSCT及三维重建技术对原发性输尿管癌具有较高的诊断价值,能为临床治疗方案的选择和预后评估提供有力帮助。     

16层螺旋CT检测冠状动脉斑块及管腔狭窄的临床应用

目的：探讨16层螺旋CT检测冠状动脉斑块的价值。方法：分析我院2006年1月至今进行16层螺旋CT冠脉检查的227例患者的图像。对造影图像利用GE公司AW4．2工作站分析软件进行容积重现（VR）、曲面重建（CPR）、最大密度投影（MIP）重建。对斑块进行分析，并对冠状动脉的狭窄程度进行分析。结果：16层螺旋CT冠状动脉造影检测钙化性斑块、混合性斑块、非钙化性斑块、冠状动脉主要分支的轻度狭窄、中度狭窄、重度狭窄。结论：16层螺旋CT冠状动脉造影是一种安全可靠的检查方法，不但可以检测出冠状动脉各分支的斑块，而且可以判断斑块的性质，并可检测冠状动脉各分支的狭窄程度。     

64层螺旋CT在评价冠状动脉桥血管中的价值

目的探讨64层螺旋CT在诊断冠状动脉桥血管的临床价值。方法对21例冠状动脉搭桥术的患者行64层螺旋CT心、胸部血管造影检查。对所有扫描原始数据行冠状、矢状MPR、曲面重建(CPR)以及VR、MIP重建。由两位有经验的放射科医生对所有图像进行观察,对桥血管狭窄进行诊断,并评价其狭窄程度。8例CT诊断桥血管重度狭窄(管腔狭窄>75%)或闭塞的患者同时行选择性血管造影检查。结果21例患者均可清晰地显示冠状动脉各主要分支,并能清晰地显示其斑块和管腔的狭窄。21例患者经螺旋CT心、胸部血管造影检查,可清晰显示52条桥血管,其中13条桥血管出现再狭窄(10条为大隐静脉桥血管,3条为乳内动脉桥血管),狭窄部位均位于桥血管吻合口处;重度狭窄7条,闭塞1条,此8条桥血管均与选择性血管的结果相吻合,CT评价冠状动脉桥血管重度狭窄的准确性为100%。结论64层螺旋CT心、胸血管造影检查不但能显示冠状动脉桥血管,而且能清晰地显示原始的冠状动脉及冠状动脉与桥血管的吻合口,是评价冠状动脉桥血管的一种有效的可靠的检查方法。     

CTA下血管重建及CT仿真内窥镜技术对主动脉夹层的诊断价值

目的 探讨螺旋CT血管造影(SCTA)后血管重建技术及CT仿真内窥镜技术对主动脉夹层的诊断价值。方法对17例主动脉夹层患者进行螺旋CT增强扫描，并进行二维及三维重建，包括表面覆盖成像(SSD)、最大密度投影重建(MIP)、多平面投影法(MPR)、曲面重建(CPR)及CT仿真内窥镜成像(CTVE)。结果SCTA横断面图像、MPR、CPR及CTVE均显示各例动脉夹层的真腔和假腔，剥离内膜及钙化，血栓亦能显示。MIP、及SSD能不同程度显示真腔和假腔及剥离内膜，能较好地显示主动脉病变的全貌，显示病变的范围、大小及分支血管受累情况。MIP可清楚显示血管管壁钙化；MPR可以对病变进行任意角度重建和观察，清楚地显示附壁血栓、真假腔、破口、钙化和内膜片；CPR可将不在同一平面的结构显示在同一二维平面上，但不能显示结构的纵深关系；CTVE能显示主动脉夹层的真腔和假腔、剥离内膜及破口。结论 应用SCTA的各种成像技术，以横断图像为基础，结合其MPR、MIP、CPR、SSD及CTVE，能够较全面地显示主动脉夹层，一定程度上取代创伤性DSA造影检查，为主动脉夹层的诊断提供一种安全可靠的手段。     

多层螺旋CT小肠造影对小肠疾病的鉴别诊断价值

目的:分析小肠疾病采用多层螺旋CT小肠造影诊断的价值。方法:选取2018年3月—2019年7月收治的疑似小肠疾病患者31例,均采用多层螺旋CT小肠造影造影检查,并采取增强扫描,进行容积重建技术(VRT)、多平面重建(MRP)、最大密度投影(MIP)等后处理,与病理结果对比,分析其诊断价值。结果:多层螺旋CT 对小肠诊断的敏感度95.65%、特异性87.50%、准确性93.55%。结论:多层螺旋CT小肠造影在小肠疾病的鉴别诊断中应用价值较高,可清晰显示小肠壁、肠壁等结构,值得应用。     

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.