孤立性肺结节多层螺旋CT动态增强扫描

孤立性肺结节（SPN）的动态CT增强诊断是近年来研究的热点之一,SPN的强化值（增强峰值-增强前CT值） 、结节-主动脉强化值比（S/A）（结节增强峰值/主动脉增强峰值）、时间-密度曲线（TDC）和灌注值（时间-密度曲线最大斜率/大动脉增强峰值）等作为诊断依据.以强化值＜15HU 、S/A＜6%考虑诊断为良性结节,恶性结节强化值通常为20-60HU,时间-密度曲线类型有利于恶性与炎性结节的鉴别.结节的强化程度与微血管密度（MVD）呈正相关性.     

多层螺旋CT灌注成像在孤立性肺结节鉴别诊断中的应用

目的探讨多层螺旋CT灌注成像在孤立性肺结节（SPN）鉴别诊断中的应用价值：方法前瞻性研究99例直径2～4cm的孤立性肺结节的32层螺旋CT灌注表现,测定肺内病灶的血容积（BV）、表面通透性（PS）、血流量（BF）、平均通过时间（MTT）的数值,并在时间-密度曲线的基础上,测量SPN增强净增值（NE）和达峰时间（TTP）;取值进行统计学分析：结果恶性、炎性-BV值均明显高于良性（P〈0．001,P〈0．05）,而恶性与炎性之间无统计学差异（P〉0．05）;PS值中,组间均有统计学羞异（所有P〈0.01）。BF值中,恶性结节〉炎性结节〉良性结节,MTT值三者接近;但BF值、MTT值组间均无统计学差异（P均〉0.05）。恶性与炙性结节的TTP值之间有统计学差异（P〈0．01）。NE值中,组间均有统计学差异（所有P〈0.05）。良性、恶性及炎性结节的TDC形态不同结论多层螺旋CT灌注成像技术有助于孤立性肺结节的鉴别诊断.     

256层CT1024矩阵灌注成像对孤立性肺结节的诊断价值

目的 探讨飞利浦256层iCT1024矩阵灌注成像在孤立性肺结节诊断中的价值。 方法 对38例孤立性肺结节患者行灌注扫描,扫描数据传至EBW工作站,用肺结节分析软件进行图像分析,获取血流量（BF）、血容量（BV）、平均通过时间（MTT）,增强峰值（PH）以及SPN与主动脉PH值比值（S/A）等指标。进行统计学分析,并与病理结果进行对照。 结果 恶性和炎性结节的BV、PH和S/A比值明显高于良性结节（P＜0.01）,而恶性与炎性之间的BV、PH、S/A比值差异则无统计意义（P＞0.05）。恶性结节、炎性结节、良性结节的TDC形态不同。 结论 256层iCT1024矩阵灌注成像有助于鉴别孤立性肺结节的良、恶性。       

CT灌注成像在孤立性肺结节中的应用

目的探讨CT灌注成像对孤立性肺结节(SPN)的诊断与鉴别诊断价值.方法对34例SPN先行薄层平扫,再行同层动态增强扫描.在动态增强时间-密度曲线基础上,测量病灶增强的最大比值(PHSPN/PTSPN)、强化峰值(PHSPN)及达到最大峰值所需的时间(PTSPN),并测量与病灶同层的主动脉峰值(PHAA).根据以上测得数据,计算SPN增强峰值与主动脉增强峰值比(PHSPN/PHAA),SPN灌注量(ml·min-1·ml-1)=SPN增强最大比值(Hu·min-1)/动脉增强的峰值(Hu).结果恶性SPN和多血性良性SPN较少血性良性SPN有更高的强化峰值PHSPN和PHSPN/PHAA.而恶性SPN与多血性良性SPN的PHSPN和PHSPN/PHAA无显著差异.多血性良性SPN增强前密度明显低于恶性SPN.恶性SPN与多血性良性SPN的灌注量明显高于少血性良性SPN.结论CT灌注成像能反映病灶的血供信息,为孤立性肺结节性质的鉴别诊断提供证据.     

MSCT灌注成像在肺结节（肿块）鉴别诊断中的价值

目的探讨MSCT灌注成像对良、恶性肺结节（肿块）的鉴别诊断价值。方法回顾性分析32例经临床确诊的肺结节（肿块）的各项CT灌注成像参数[血流量（BF）、血容量（BV）、平均通过时间（MTr）、毛细血管表面通透性（PS）]及各参数值的临床意义。结果（1）轻中度强化组：恶性肺结节（肿块）的BF、BV、PS值均明显高于良性肺结节（肿块），差异有非常显著性（P〈0．01）；恶性肺结节（肿块）的MTT值高于良性肺结节（肿块），差异有显著性（P〈0．05）。（2）明显强化组：恶性肺结节（肿块）BV、PS值高于良性肺结节（肿块），差异有显著性（P〈0．05），BF、MTT值差异无显著性（P〉0．05）。结论MSCT灌注成像有助于良、恶性肺结节（肿块）的鉴别诊断。     

多排螺旋CT对肺内孤立性结节诊断的探讨

目的用多因素回顾性研究的方法,探讨肺内直径≤3em的孤立性结节（SPN）定性诊断的可能性,并评价多排螺旋CT的鉴别诊断价值。方法搜集经证实的直径≤3cm的SPNs病例80例,通过对病灶的强化时间-密度曲线（T-DC）模式、肺内结节的CT形态学特征等行多因素分析,探讨SPN定性诊断的相关因素。结果恶性、良性及炎性结节显示了不同的T—DC模式。睬分叶征、钙化在小肺癌与良性结节两组病例间有显著统计学差异。肺结节内点状、多点状透亮影在良、恶性结节中出现率有显著差异。结论多排螺旋CT对病变全方位显示,动态对比增强功能CT提供了SPN血流模式的定量信息,结合临床资料,能较好地无创地定性诊断,从而提高肺内孤立性小结节的诊断率。     

CT灌注成像反映肺内病变生理学状态的应用

目的:计算孤立性肺结节的CT灌注参数,评价CT灌注成像在肺内病变的功能成像方面的价值.方法:收集2003-02/2005-03解放军总医院收治、资料完整的孤立性肺结节病例73例,其中恶性58例,良性15例.所有患者行CT灌注成像,得出病灶的CT灌注参数,包括血流量病灶血流量、血容量、平均通过时间和表面渗透性,并在不同界值水平计算其诊断特性.结果:恶性结节的血流量高于良性结节,血容量低于良性结节,但两者之间差异无显著性意义(P＞0.05);恶性病灶的平均通时间低于良性病灶,表面渗透性高于良性结节(P＜0.05).②鳞癌的血流量、血容量及表面渗透性低于腺癌(P＜0.05),平均通过时间高于腺癌,但统计学差异无显著性意义(P＞0.05).③以平均通过时间≤7 s作为恶性病变的域值,则灵敏度为8.97%,特异度66.67%,准确度为68.49%,阳性预测值88.89%,阴件预测值为35.71%.以表面渗透件≥0.2 ML/(min·g)作为恶性病变域值,灵敏度为86.21%,特异度53.33%,准确度为79.45%,阳性预测值87.72%,阴性预测值为50.0%.结论:CT灌注成像能够反映病变的生理学状态,可以更准确地评价肺内结节性病变.     

颈部淋巴结病变的CT灌注成像研究

【目的】探讨CT灌注成像在颈部淋巴结病变中的诊断价值。【方法】对58例颈部淋巴结病变患者进行CT灌注成像检查,其中恶性22例,良性36例,分析比较不同病理类型淋巴结病变的时间-密度曲线（TDC）和CT灌注参数差异。【结果】淋巴结恶性病变TDC多为A型（66．7％）,淋巴结良性病变TDC多为C型（54．6％）,B型曲线在良性和恶性淋巴结病变中均可见到;淋巴结恶性病变的灌注血流量（BF）值及血容量（BV）值均高于良性病变（P〈0．05）,腺癌淋巴结转移灶BF值及BV值高于鳞癌淋巴结转移灶及淋巴瘤,鳞癌淋巴结转移灶的BF值高于淋巴瘤,淋巴瘤的平均通过时间（MTT）值长于鳞癌及腺癌淋巴结转移灶（P〈0．05）。【结论】不同病理类型的颈部淋巴结病变的灌注特点不同,CT灌注成像有助于颈部淋巴结病变的鉴别诊断。     

动态增强CT对肺孤立结节的定性诊断价值

目的 评价同层动态CT增强扫描对肺孤立结节的定性诊断价值.方法 选用直径≤3cm的肺孤立结节38例,先行平扫,再静脉注入碘剂（Omnipaque）100mL,间隔1min,延迟10min,对结节中心层面动态扫描,检测增强前后CT值,并绘出时间-密度曲线.结果 结核球强化净值＜20Hu,动态曲线呈平坦型.恶性肿瘤和炎性结节强化净值＞20Hu,动态曲线呈上升型,延迟至10min.两者强化净值出现明显差异,动态曲线可分开.结论 ①动态同层增强扫描提高了肺孤立结节的鉴别诊断价值.②动态同层CT增强扫描的延迟时间应延长至10min,增加数据采集点.③时间-密度曲线延迟至10min,恶性结节和炎性结节的动态曲线可以分开.     

孤立性肺结节MSCT动态增强扫描时相的研究

目的探讨肺孤立性结节同层动态cT增强扫描的时相。方法对42例直径10～40mm,无空洞和钙化者的肺孤立性结节病灶中心行系列同层动态增强扫描,测量其增强前后的CT值,绘制其时间密度曲线。结果良、恶性结节强化后具有不同的时间-密度曲线模式和cT净增值。肺癌的cT增强值[（353±17．2）]HU高于结核的cT增强值[（4．5±4．3）HU]（P〈0.01）;炎性结节的cT增强值f（45．2±4．9）HU]与肺癌的cT净增值比较差异无显著性（P〉0.05）。肺癌以1～2min达峰值为主,平均达峰值后多数呈平台型,降幅不超过20％,而炎性结节以1．5～5min达峰值为主,达峰值后形态不规则;肺结核的曲线呈平缓走行,无明显起伏。结论cT同层动态增强扫描检查技术的正确运用至关重要。     

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.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.