MRI诊断剖宫产术后瘢痕妊娠

目的 探讨MRI诊断剖宫产术后瘢痕妊娠(CSP)的价值。方法 回顾性分析29例经手术证实为CSP患者的MRI资料,观察平扫及增强扫描特征。结果 29例患者MRI均清楚显示孕囊位于子宫前下段峡部瘢痕后方,20例呈囊状,增强扫描囊壁均匀强化,囊内容物无强化;9例呈不规则包块,增强扫描包块边缘呈不规则强化。23例孕囊向子宫肌层浸润的同时又向宫腔内生长;6例不同程度向子宫肌层浸润。子宫瘢痕均表现为条状等T1、短T2异常信号。结论 MRI平扫及增强扫描可明确诊断CSP。     

超声鉴别诊断瘢痕妊娠与宫腔下段非瘢痕妊娠

目的 观察二维及三维超声诊断剖宫产瘢痕妊娠（CSP）与宫腔下段非瘢痕妊娠的价值。方法 收集67例CSP患者（CSP组）和29例宫腔下段非瘢痕妊娠患者（宫腔下段非瘢痕妊娠组）,以二维及三维超声观察孕囊种植部位、与剖宫产瘢痕关系和滋养血流主要来源部位,并测量剖宫产瘢痕处残余肌层厚度;建立Logistic回归模型,以ROC曲线评价其诊断效能。结果 CSP组与宫腔下段非瘢痕组间孕囊与瘢痕关系、滋养血流来源部位及瘢痕处残余肌层厚度差异均有统计学意义（P均<0.001）。Logistic回归模型显示ROC曲线下面积为0.878（P<0.001）。以预测概率=0.680为临界值,该模型预测CSP的准确率为86.46%,敏感度为89.55%,特异度为79.31%。以孕囊植入瘢痕和滋养血流来源于子宫前壁下段为诊断CSP的标准,二维与三维超声诊断CSP和宫腔下段非瘢痕妊娠的Kappa值分别为0.699和0.711。结论 通过Logistic回归模型综合分析孕囊与瘢痕关系、滋养血流来源部位和瘢痕处残余肌层厚度,可提高对CSP与宫腔下段非瘢痕妊娠的鉴别效能。     

MRI联合经阴道超声对剖宫产术后子宫瘢痕妊娠的诊治指导价值

目的:探讨MRI联合经阴道超声对剖宫产术后子宫瘢痕妊娠(CSP)的诊治指导价值。方法:回顾分析2016～2018年32例经手术或及病理证实的CSP患者的MRI和经阴道超声的影像学特征并综合判断,并对临床治疗方式的选择分析。结果:32例患者术前MRI和阴道超声正确诊断为CSP分别为30例(准确率90.6%)和27例(84.3%)。①MRI和阴道超声检查均清楚显示妊娠囊位于子宫腔下段剖宫产瘢痕处,可分为单纯妊娠囊型23例(切口处孕囊完全和切口处及宫腔下段部分植入型分别7例、16例)和混合团块型9例,单纯妊娠囊型超声表现为孕囊回声,部分呈"双环征"或"鸟嘴样"改变;MRI表现为孕囊包膜T1WI稍等信号、T2WI稍高信号,囊内容物T1WI、T2WI分别为低信号、T2WI高/高低混合信号,增强扫描显示囊壁部位出现均匀强化,囊腔不强化或部分为不均强化。混合团块型超声表现为杂乱中、低回声,MRI表现为T1WI等、稍低或稍高混杂信号,T2WI不均高低混杂信号,增强扫描为明显不均强化。②妊娠囊向子宫肌层内种植生长MRI和阴道超声分别诊断15例、10例;根据切口处妊娠物生长方式及邻近肌层血供判断种植程度:切口处肌层及妊娠物的血供MRI表现为强化程度和方式不同,超声CDFI示血流信号丰富程度不同;宫腔内积血MRI通常表现为T1WI高信号T2WI混杂信号,超声表现为不均质出血回声。③临床治疗方式:32例中7例采取药物+超声引导下行清宫术,16例行腹式子宫瘢痕妊娠物切除术+子宫修补术,其中5例行药流后清宫术后出血不止行腹式子宫瘢痕妊娠物切除术;9例行超声引导下宫腔镜瘢痕妊娠物切除术。结论:MRI和经阴道超声正确诊断CSP的准确率均较高。CSP的阴道超声和MRI表现均具有各自影像学特点,联合二者诊断将为临床快速诊断CSP提供更全面详细的信息,并对临床治疗方式选择具有重要指导意义。     

不同超声分型剖宫产术后子宫瘢痕妊娠的预后分析

目的对比剖宫产术后子宫瘢痕妊娠(CSP)的超声分型及预后,为早期诊断和个体化治疗方案的制定提供客观依据。方法回顾性分析我院收治283例CSP患者的超声声像图特征,总结不同分型所采取的治疗方式并进行预后分析。结果Ⅰ型103例(妊娠囊边缘位于切口处),Ⅱ型112例(妊娠囊陷入切口内),Ⅲ型10例(妊娠囊向膀胱方向突出),Ⅳ型58例(妊娠囊呈混合回声)。结合临床症状及实验室结果进行对比分析:Ⅳ型较Ⅰ、Ⅱ、Ⅲ型停经时间长(P0.05),Ⅳ型较Ⅰ、Ⅱ、Ⅲ型血HCG值低(P0.05),Ⅰ型较Ⅱ、Ⅲ、Ⅳ型子宫前壁峡部肌层厚度大(P0.05)。Ⅰ型主要治疗方式为超声监护下清宫术;Ⅱ型根据临床实际情况,选择直接超声监护下高危清宫术或预处理后行超声监护下清宫术;所有Ⅲ型均需预处理后行超声监护下清宫术;Ⅳ型主要治疗方式为预处理后行超声监护下清宫术。其中2例CSPⅠ型坚持继续妊娠至足月,1例为凶险性前置胎盘伴胎盘植入,经剖腹产术中出血800ml;1例为前置胎盘伴胎盘粘连,经剖腹产术中出血700ml。结论准确的CSP超声分型有助于制定针对CSP的个体化治疗方案以改善患者预后。     

剖宫产瘢痕妊娠的MRI特点及MRI对其诊治指导价值

目的：探讨剖宫产瘢痕妊娠（CSP）的MRI特点及MRI对其临床诊治的指导价值。方法：回顾性分析2008年7月～2010年4月MRI确诊或怀疑CSP术后证实为CSP患者33例MRI特点及临床治疗过程,并对手术术式的选择进行分析。结果：①妊娠囊特点：22例妊娠囊包膜完整,表现为等T1或稍长T1、长T2环形信号影;囊内容物表现为长T1长T2信号;增强扫描囊壁强化明显、均匀,内容物强化不明显。12例妊娠囊包膜不完整,表现为T1WI图像等T1或稍长T1信号,T2WI图像稍长T2、等T2、稍短T2信号;囊内容物为稍长T1长T2、长T1长T2、长T1等T2、等T1等T2混杂信号。②妊娠囊与瘢痕、宫腔、宫颈管及邻近子宫壁关系：18例妊娠囊种植于瘢痕上,植入子宫壁较浅,与瘢痕及相邻子肌层分界较清晰。子宫壁最薄处约3～10mm。15例妊娠囊位于瘢痕深部,向子宫肌层生长或向子宫肌层及宫腔同时生长,子宫壁最薄处约2～4mm,其中4例压迫膀胱。③临床治疗过程：33例中3例采取超声检测下行刮宫术;3例行开腹病灶切除术,其中1例由宫腔镜探查后改行开腹病灶切除术;3例行阴式病灶切除术;1例行阴式剖宫取胎术,术中出血不止行阴式全子宫切除术;16例行超声检测下宫腔镜CSP病灶切除术。结论：CSP的MRI表现具有一定特异性征象,结合临床能很好的指导临床诊治,对手术术式选择具有重要指导意义。     

产前MRI诊断及随访胎儿侧脑室前角旁囊肿

目的 评价产前MRI诊断胎儿侧脑室前角旁囊肿的价值,并随访观察胎儿转归。方法 回顾性分析44胎侧脑室前角旁囊肿胎儿,并跟踪随访观察其MRI特征及妊娠结局。结果 44胎中,23胎Ⅰ型、11胎Ⅱ型及10胎Ⅲ型侧脑室前角旁囊肿;T1WI见侧脑室前角旁类圆形/椭圆形、条形低信号,T2WI呈高信号,边界清晰;其中22胎合并其他颅内、外畸形。3种类型囊肿位置（单/双侧）差异无统计学意义（P>0.05）,Ⅰ型与Ⅱ型、Ⅱ型与Ⅲ型囊肿性质（单/双囊）差异具有统计学意义（P均<0.0167）;左、右侧囊肿最长径差异均具有统计学意义（P均<0.05）。其中19例出生后复查MRI,4例囊性病灶消失,8例病灶较胎儿期缩小,7例无明显改变。结论 产前MRI可为胎儿侧脑室前角旁囊肿产前咨询及出生后早期干预提供依据;侧脑室前角旁囊肿胎儿预后与其类型、大小及伴发畸形密切相关。     

MRI诊断卵巢黄体囊肿破裂

目的 探讨卵巢黄体囊肿破裂（OCLCR）的MRI表现。方法 回顾性分析经手术病理证实的28例OCLCR的临床、MR影像资料。结果 28例附件区可见单囊、多囊或多房囊性包块,长径3.0～12.0 cm。根据肿块形态不同在MRI上分为3型：Ⅰ型为单囊型,17例,根据单囊与血肿位置不同又分为2种亚型,Ⅰa型（囊内血块型）8例,Ⅰb型（囊肿旁血肿型）9例;Ⅱ型为多囊型,5例;Ⅲ型为多房型,6例。增强扫描25例,囊壁及分隔厚约2.5～5.0 mm,呈环形、分隔状明显强化,20例囊壁见破裂口表现环形强化连续性中断、塌陷或缺损。与手术病理结果对照,MRI对OCLCR破裂口的诊断敏感度为90.91%（20/22）、特异度为100% （6/6）,准确率为92.86%（26/28）。MRI与手术病理诊断的一致性高（Kappa=0.81,P<0.001）。结论 OCLCR MRI表现附件区单囊、多囊或多房厚壁囊肿,MRI能准确识别囊壁破裂口,与手术病理具有高度一致性。     

超声阴性胎盘早剥MRI表现及其诊断价值

目的 观察超声无阳性发现的胎盘早剥的MRI表现及其诊断价值。方法 收集53例产后确认为胎盘早剥孕妇的产前MRI,观察胎盘位置、血肿位置、分期及其与胎盘早剥分型和妊娠结局的关系。结果 16例胎盘位于子宫前壁及侧壁,37例胎盘位于子宫底及后壁。53例均可见胎盘血肿;29例血肿位于胎盘绒毛膜下,表现为新月形和弧形异常信号,T1WI、T2WI及DWI多呈高信号;24例血肿位于底蜕膜下,其中9例单纯底蜕膜下血肿表现为三角形和梭形异常信号,T1WI多呈等信号、T2WI及DWI呈高信号, 15例绒毛膜及底蜕膜下连续血肿表现为梭形、弧形或新月形异常信号,T1WI和T2WI多呈高信号,DWI呈低信号。32例血肿渗透至胎盘内,其中16例胎盘增厚。34例胎盘与子宫壁分离,胎盘母体面与子宫肌层之间存在间隙。不同位置胎盘早剥分型和妊娠结局差异均无统计学意义（P均>0.05）。底蜕膜下血肿较绒毛膜下血肿、急性期血肿较非急性期血肿更易发生重型胎盘早剥及接受急诊剖宫产（P均<0.05）。结论 MRI有助于判断胎盘血肿位置及分期,预测胎盘早剥分型;发现底蜕膜下急性出血时应予紧急处理。     

子宫切口瘢痕妊娠的MRI影像诊断

目的:探讨子宫切口瘢痕妊娠的MRI表现及诊断价值。方法:回顾性分析65例经手术病理证实的子宫切口瘢痕妊娠患者的MRI表现,总结其MRI特点。结果:65例子宫切口瘢痕妊娠MRI均清楚显示孕囊,位于子宫峡部前壁切口瘢痕处,其中1例绒毛与子宫肌层有粘连。47例为内生型,15例为外生型。孕囊为圆形或椭圆形,呈T1WI低信号、T2WI高信号,囊壁光滑。3例呈肿块样改变,边界欠清,形态欠规则,T1WI、T2WI呈混杂信号,其中1例穿透子宫肌层,肿块周围见血管流空信号。DWI囊壁及胚芽呈高信号。增强扫描囊壁呈环形强化。结论:子宫切口瘢痕妊娠MRI能准确显示孕囊部位、生长方式和信号特征,为临床早期明确诊断及选择合适的治疗方案提供了重要的影像依据。     

经阴道彩色多普勒超声对剖宫产切口瘢痕妊娠的临床价值

目的探讨剖宫产切口瘢痕妊娠的声像图特征,评价经阴道彩色多普勒超声对剖宫产切口瘢痕妊娠的临床诊断价值。方法对30例在中山大学附属东华医院住院治疗的剖宫产切口瘢痕妊娠者的超声特征进行回顾性分析,观察妊娠囊位置、子宫切口部位回声、瘢痕处肌层厚度、妊娠囊与子宫切口关系以及血流分布。结果 30例剖宫产切口瘢痕妊娠者超声诊断正确18例,误诊2例,诊断符合率为93.3%。所有孕妇在宫腔正常位置未见妊娠囊,在子宫下段切口部位可见妊娠囊或混合性团块,妊娠囊或团块与膀胱之间的子宫肌层明显变薄。根据声像图特征,将子宫下段瘢痕妊娠分为妊娠囊完全嵌于瘢痕型（13例）、妊娠囊部分向宫腔内生长型（6例）及瘢痕处混合性团块型（11例）。彩色多普勒血流图（CDFI）观察瘢痕处妊娠囊或混合性团块周边可见丰富的血流信号,PW显示平均RI值〈0.5。结论经阴道彩色多普勒超声能对剖宫产切口瘢痕妊娠提供较准确的定位和定性诊断,有重要的临床价值。     

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.