肝脏局灶性病变的超声造影体会

目的对比分析超声造影与常规超声检查在鉴别诊断肝脏局灶性病变中的价值。方法肝脏局灶性病变患者135例,使用常规超声和超声造影两种方法对比检查,比较二者诊断肝脏局灶性病变的敏感性、特异性和准确性。结果本组135例病例中,常规超声诊断肝脏局灶性病变的敏感性、特异性和准确性分别为69．9％、88．5％和77．0％;超声造影诊断肝脏局灶性病变的敏感性、特异性和准确性分别为89．2％、92．3％和90．4％。二者敏感性和准确性比较,差异有统计学意义（P〈0．01）。结论常规超声检查法可以敏感地检出肝内局灶性病变,可应用于日常工作中筛查肝脏疾患;超声造影检查法则可对常规超声难以确诊的病例进行鉴别诊断,进一步提高超声诊断肝肿瘤的准确性。     

实时超声造影对不超过2cm肝细胞癌定性诊断的临床研究

目的评估实时超声造影对≤2cm肝细胞癌的诊断价值。方法实时超声造影检查104个直径≤2．0cm的肝局灶性病变，造影剂为声诺维，成像技术采用对比脉冲序列。评估超声造影对其中49个肝细胞癌的诊断价值，并与普通超声比较。结果49个肝细胞癌病灶超声造影动脉期43（87．8％）个高增强，5个（10．2％）等增强，1个（2．0％）低增强。39（79．6％）个在门静脉期及延迟期增强消退为低增强。普通超声和超声造影定性诊断≤2cm肝细胞癌的敏感性、阴性预测值、准确性分别为28．6％（14／49）vs79．6％（39／49），P〈0．001；59．8％（52／87）vs90．7％（39／43），P=0．002；63．5％（66／104）vs86．5％（90／104），P〈0．001。结论实时超声造影比普通超声显著提高了对≤2cm肝细胞癌的诊断能力，但假阴性率偏高，应予注意。     

常规超声与超声造影鉴别移植肝局灶性病变的比较研究

目的 比较常规超声和超声造影鉴别移植肝局灶性病变的诊断性能.方法 对68例移植肝局灶性病变行常规超声和超声造影检查.两位不同经验的超声医生(受试者)对检查结果独立诊断,比较常规超声和超声造影鉴别移植肝局灶性病变良恶性的敏感性、特异性和准确性,Kappa值评估受试者之间的一致性.结果 超声造影对不同经验的受试者均能显著提高鉴别病变良恶性的敏感性和准确性(均P<0.05),缺乏经验的受试者提高的幅度较大.两位受试者之间的一致性超声造影较常规超声高,к值分别为0.931和0.632.结论 超声造影可显著提高对移植肝局灶病变的鉴别诊断能力.     

超声造影与常规超声鉴别诊断附件区肿块的比较研究

目的 比较常规超声和实时超声造影对附件区肿块的鉴别诊断性能.方法 对137例附件区肿块行常规超声和实时超声造影检查.两位超声医师(受试者)对检查结果独立作出诊断,用ROC曲线评估常规超声和实时超声造影对附件区肿块的鉴别诊断性能,Kappa值评估受试者之间的一致性.结果 ROC曲线显示两位受试者得到的曲线下面积:常规超声分别为0.731和0.738,超声造影分别为0.891和0.903(P＜0.01).超声造影能明显提高判别病变良恶性的准确性.受试者之间的一致性超声造影高于常规超声,κ值分别为0.893和0.681.两位受试者对附件区病变的诊断正确率常规超声分别为73.2％和74.2％,超声造影分别为90.7％和91.2％(均P＜0.01).结论 实时超声造影可明显提高超声对附件区病变的鉴别诊断能力.     

肝良性占位病变低机械指数反向脉冲谐波实时超声造影研究

目的 利用超声造影剂SonoVue及实时超声造影技术观察肝良性占位病变造影剂灌注特点，探讨其对肝良性占位病变分类诊断的意义。方法 选择103例病理证实的肝良性占位病变患者（血管瘤33例，肝硬化增生结节11例，肝细胞腺瘤3例，胆管细胞腺瘤1例，局灶性结节增生6例，局灶性坏死11例，炎性假瘤4例，肝脓肿18例，局灶性脂肪浸润不均匀14例，血管平滑肌脂肪瘤2例），采用超声造影剂SonoVue（2．4ml团注）和低机械指数（M10．09～0．15）反向脉冲谐波造影成像技术进行实时超声造影观察。结果 81．8％（27／33）肝血管瘤表现为周边结节状增强及向心性增强模式；83．3％（5／6）局灶性结节增生早期动脉相显示“轮辐状”增强；90．9％（10／11）肝硬化增生结节和100％（14／14）局灶性脂肪浸润不均匀超声造影变化与周边肝组织基本一致；腺瘤及血管平滑肌脂肪瘤动脉相均显示快速整体增强100％（6／6），延迟相83．3％（5／6）显示为等回声或高回声；92．9％（13／14）局灶性坏死和炎性假瘤超声造影病灶内未见增强；94．4％（17／18）肝脓肿造影后病灶内出现大小不等的无回声区呈融合状，与周围肝组织界线清楚。结论 低机械指数反向脉冲谐波实时超声造影可准确显示大多数肝良性占位病灶的不同灌注特点，对分类诊断具有重要价值。     

声触诊组织量化技术在肝脏局灶性病变中的初步应用

目的探讨声触诊组织量化技术（VTQ）在肝脏局灶性病变中的初步应用价值。方法对97例肝脏局灶性病变的患者进行VTQ检查,对各病变组和对应肝背景VTQ值,良恶性病变VTQ值进行对比分析,应用ROC曲线计算鉴别肝脏良恶性占位VTQ测值的阈值。结果原发性肝癌、转移性肝癌及肝血管瘤与各对应肝背景VTQ值比较,差异有统计学意义（P〈0．05）,血管瘤与原发性肝癌及转移性肝癌VTQ值比较,差异有统计学意义（P〈0．05）。良性病变与恶性病变VTQ值比较,差异有统计学意义（P〈0．05）。ROC曲线分析阈值,当VTQ值≥1．85m／s时,肝脏局灶性病变诊断为恶性的敏感度和特异度均为78％,阳性预测值和阴性预测值分别为80％和77％。结论VTQ可用于肝脏局灶性病变的检测,有助于鉴别肝脏局灶性病变的良恶性。     

彩色多普勒超声造影在肝肿瘤诊断中的应用

目的：评价Levovist在肝肿瘤常规彩色多普勒超声造影诊断中的价值。方法：对经手术及（或）病理证实的125例肝内实质占位病变患者（126个病灶）进行经周围静脉的超声造影，其中原发性肝癌79例，转移性肝癌4例，肝血管瘤13例，肝局灶性结节性增生7例，肝炎性假瘤7例，其他良性病变15例，选用浓度为400mg/ml的Levovist超声造影剂。结果：肝癌在造影前彩色血流表现为Ⅲ及级以上者仅为1．2％（1／83），造影后Ⅲ级及以上血流者达49．4％（41／83），并且28个无彩色血流的肝癌造影后有血流者达92．8％（26／28）。而肝良性病变内血流造影前均为Ⅱ级以下，其中0级血流占46．5％（20／43），而造影后血流者占76．7％（33／43），造影后肝恶性肿瘤的阻力指数（0．82）明显高于肝良性病变（0．56），肝恶性肿瘤增强出现时间（平均31S）明显早于肝良性病变（平均41S），而增强持续时间（平均124S)明显短于肝良性病变（平均248S），超声诊断肝肿瘤的符合率从造影前的66．7％（84／126）提高到94．4％（119／126），结论：经周期静脉肝超声造影对肝肿瘤的超声定性诊断有很大帮助。     

超声造影在肝局灶性病变的诊断价值

目的探讨超声造影在肝局灶性病变的诊断价值。方法采用超声造影连续脉冲对比（PS）技术和造影剂灌注定量（ACQ）分析软件,观察56例肝局灶性病变患者（61个病灶）始增时间、达峰时间、峰值强度,比较良性恶性之间的差异性。结果肝恶性病灶始增时间（12．69±2．09）S、达峰时间（23．14±5．24）S,均明显短于良性病灶及周围肝组织（P〈0．05）;峰值强度（26．02±3．44）dB,与良性病灶相比差异无统计学意义（P〉0．05）,二者均明显高于周围肝组织（P〈0．05）。结论超声造影诊断中,可以将始增时间、达峰时间作为鉴别诊断肝脏良、恶性病灶特异性参数指标。     

超声造影在腹部实质脏器创伤快速分类治疗中的价值

目的探讨超声造影在腹部实质脏器创伤快速分类治疗中的作用。方法对105例腹部实质脏器创伤患者的超声造影结果进行回顾性分析,并与CT和（或）手术结果进行对照。超声造影引导注射治疗的方法是在超声造影引导下,首先于肝、脾或肾创伤灶内多点注射蛇毒凝血酶,继之于肝、脾创伤灶和活动性出血部位多点注射旺一氰基丙烯酸酯黏合胶;保守治疗的方法是卧床休息、常规给予抗生素和补充血容量。结果在所有105例患者中,超声造影与增强CT两者诊断结果有很好的一致性（P〈0．001）;在手术治疗的19例患者中,超声造影与手术诊断结果完全一致。在105例肝、脾、肾创伤患者中,保守治疗28例,超声造影引导注射治疗58例,手术治疗19例。保守治疗、超声造影引导注射治疗和手术治疗率分别为26．7％（28／105）、55．2％（58／105）和18．1％（19／105）,非手术治疗率为81．9％（86／105）。结论通过超声造影对创伤伤情的分类,所有患者得到快速、安全和有效的治疗。     

肝硬化增生结节的超声造影模式及诊断价值

目的 通过观察超声造影对肝硬化背景下增生结节的灌注过程及回声变化规律，探讨增生结节的造影模式，并评价超声造影对肝硬化增生结节的诊断价值。方法 采用SonoVue实时灰阶超声造影，观察78例肝硬化合并占位病变及小结节195灶。最终确诊41例48灶肝细胞癌合并增生结节83灶，37例为单纯性肝硬化增生结节64灶；以147灶增生结节为研究对象。47例92灶在超声造影后30～60min内行穿刺活检确诊，余31例55灶增生结节经临床以及影像诊断随访6个月以上，并行多次血清甲胎蛋白检查确诊。比较增生结节造影前后诊断率。结果 超声造影增生结节呈四种灌注模式：模式一，61灶（41．5％），动脉期、门脉期及实质期与肝呈同步灌注；模式二，31灶（21．1％），为延迟增强，其后与肝同步；模式三，46灶（31．3％），主要显示为实质期轻度退出；模式四，9灶（6．1％），为各期均无灌注。超声造影前43．5％（64／147）难以定性或考虑为恶性，造影后根据动脉期无明显增强，实质期无明显退出的诊断标准，96．6％（142／147）可明确排除恶性。造影前后诊断率差异有统计学意义（P〈0．05）。结论 对肝硬化背景下增生结节超声造影增强模式的认识大大提高了肝内增生结节的定性诊断率，超声造影可作为肝硬化患者合并小结节病变的有效筛选手段。     

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.     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.     

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.