12例被误诊的颅内静脉窦血栓形成患者的 临床特点分析

目的:探讨被误诊的颅内静脉窦血栓形成(CVST)患者的临床特点、辅助检查及误诊情况。方法:回顾性分析12例被误诊的CVST患者的临床资料。结果:12例CVST患者分别误诊为蛛网膜下腔出血、血管性头痛、肥厚性脑膜炎、脑梗死、良性颅内高压、神经性头痛各1例,脑出血2例,脑炎4例。平均误诊时间为21.3 d(1~90 d)。头痛为CVST的最常见临床表现。脑脊液检查常为CVST的诊断提供重要线索。MRI联合MRV检查常作为CVST的首选检查方法。结论:CVST临床表现缺乏特异性,容易误诊,头痛是最常见症状,当患者出现不典型头痛和颅内压增高时,应高度警惕为CVST的可能,颅脑CT检查未见明显异常时,应及早行MRV检查,必要时DSA检查明确诊断,以减少误诊。     

颅内静脉窦血栓形成的早期影像学特征

目的探讨颅内静脉窦血栓形成（CVST）的早期头部CT、MRI及磁共振静脉成像（MRV）影像学特征,为诊断CVST的影像学检查的选择提供依据。方法回顾性分析2009年1月-2013年1月经临床和影像学检查确诊的46例CVST患者的临床资料及头部CT、MRI、MRV影像学特征。结果头部CT显示CVST的直接征象15例（32．6％）,间接征象8例（17．4％）;MRI显示CVST的表现17例（68．0％）;MRI＋MRV检查的阳性率为87．5％,MRI＋MRV与DSA的符合率为84．6％。结论根据临床病史高度怀疑CVST患者的头颅CT可作为筛查手段,MRI合并MRV检查对明确CVST的诊断有较高价值。     

脑静脉(窦)血栓形成的影像学特点

目的:探讨脑静脉(窦)血栓形成(CVST)的影像学表现。方法:回顾性分析61例CVST患者的头颅CT、MRI、磁共振静脉血管造影(MRV)及数字减影血管造影(DSA)表现。结果:分别有61、49及59例患者行头颅CT、MRI及DSA检查。6例(6/7)急性患者,CT存在直接和间接征象,而11例(11/13)亚急性与33例(33/41)慢性患者CT无异常。急性与慢性患者MRI主要表现为静脉窦内T1低信号、T2高信号,亚急性期主要是T1、T2高信号。随着病程延长,静脉性脑梗死发生率下降(3/6,5/11,6/32),但空蝶鞍的机率增加(0,1/11,10/32)。8例行MRV检查的患者,均发现静脉(窦)充盈缺损或中断。MRI结合MRV技术可对行MRI检查的49例患者中的35例进行确诊,但11例慢性与3例亚急性患者,CT、MRI(V)均未发现异常,行DSA检查才得以确诊。结论:对急性CVST而言,头颅CT是一种简单、有效的诊断方法;而对亚急性与慢性患者,MRI具有更高敏感度与特异性;MRV可快速、无创地诊断CVST。如果头颅CT、MRI、MRV仍不能明确诊断,应尽快行DSA检查,尤其是皮层静脉以及深静脉血栓形成患者。     

颅内静脉窦血栓形成20例临床分析

目的:探讨颅内静脉窦血栓形成(cerebral venous sinus thrombosis,CVST)的临床特点、影像学检查和诊治方法,为临床提供经验。方法:回顾分析20例CVST患者的临床资料,分析其发病原因、临床特点、实验室检查、影像学表现、治疗方案等。结果:20例患者均为中青年,大多为急性或亚急性起病,临床表现主要为高颅压综合征或局灶性神经功能缺损,出现头痛17例、视力障碍8例、肢体乏力麻木10例、癫痫发作6例。CVST的诊断主要依靠影像学表现。根据19例患者的磁共振静脉血管成像(magnetic resonance renography,MRV)或数字成影血管造影(digital subtraction angiography,DSA)检查结果(去除1例无效数据)发行,血栓累及2个或2个以上静脉窦15例(78.9%),累及上矢状窦9例、橫窦15例、乙状窦14例;脑实质损伤8例(40%)。经抗凝、降颅压和抗癫痫等对症治疗后,治疗有效(症状完全消失/缓解)17例(85%),无效3例(15%),病死2例。结论:CVST发病率低,容易漏诊和误诊,头痛、视力障碍、癫痫和肢体感觉运动障碍为常见临床表现,孤立性头痛和孤立性视乳头水肿(视物模糊/黑朦)患者需警惕CVST;D-二聚体检查阴性不足以排除CVST诊断;CT和MRI检查对CVST有重要提示作用,经静脉造影检查(MRV或DSA)发现血管腔内血栓是CVST确诊的关键;早期诊断,规范的抗凝治疗和积极的对症治疗有助于改善预后。     

脑静脉窦血栓形成的诊断及治疗

目的:探讨脑静脉窦血栓形成(CVST)的临床特点。方法:对20例CVST患者的一般情况、病因、临床表现、脑脊液特点、影像学特征、治疗及预后等资料进行回顾性分析。结果:20例患者多表现为头痛,可伴有癫疒间发作和各种神经功能缺损的症状体征,脑脊液压力明显升高,白细胞数和蛋白质定量可正常或升高,头颅CT示静脉窦高密度改变及脑实质异常信号,MRI示静脉窦异常信号,MRV示静脉窦闭塞或充盈缺损,DSA示静脉窦狭窄、血流中断或不显影。治疗以脱水、抗凝、溶栓为主,19例好转,1例死亡。结论:对于高颅压伴或不伴神经、精神障碍的患者,须高度警惕CVST,应尽早行MRV或DSA检查,治疗以抗凝、溶栓为主。     

脑静脉窦血栓形成65例临床与影像学分析

目的 探讨脑静脉窦血栓形成(CVST)的病因、临床表现及影像学特点.方法 回顾性分析65例CVST患者的临床表现、头颅CT、MRI、磁共振静脉血管造影及数字减影血管造影(DSA)特点.结果 本组65例CVST患者中,25例(38%)患者仅表现为单纯颅高压;头面部局部或全身感染者13例(20%);贫血4例(6%);服用避孕药史4例(6%);结缔组织及相关疾病4例(6%)(Behcet's病2例,系统性红斑狼疮2例),蛋白C缺乏2例(3%).9例急性患者的头颅CT平扫发现,2例存在"稠密三角征",3例存在"条带征".亚急性患者头颅MRI显示,静脉窦内主要为T1、T2高信号(33%,4/12).MRI发现急性、亚急性及慢性患者静脉性脑梗死的比例分别为38%(3/8)、33%(4/12)及18%(6/33).在行MRV检查的12例患者中,均发现静脉窦充盈缺损或中断(100%).DSA检查发现66%(40/61)累及2个或2个以上静脉窦,11%(7/61)累及大脑浅(深)静脉.结论 CVST病因复杂,起病形式多样,临床表现主要为颅高压等一些非特异性症状及体征;头颅CT及MRI分别对急性,亚急性CVST静脉窦内的血栓有较高的敏感性与特异性;MRV可快速、无创地诊断CVST.若以上检查仍不能明确诊断,应尽快行DSA检查,尤其是大脑浅(深)静脉血栓形成患者.     

脑静脉窦血栓形成的CT、MRI诊断

目的:探讨CT、MRI及MRV对脑静脉窦血栓形成(CVST)的诊断价值。材料与方法:回顾性分析15例脑静脉窦血栓形成的头颅CT、MRI及MRV表现。结果:所有患者均行头颅CT和MRI平扫,其中5例行CT增强扫描,3例行MRI增强扫描,11例行MRV检查。CT平扫显示静脉窦密度增高,急性7例(7/9),亚急性3例(3/6);MRI平扫显示13例静脉窦内有异常信号,CT及MRI增强扫描均见"空三角征"或"充盈缺损征",11例MRV均表现为受累静脉窦不显影或充盈缺损。结论:头颅CT是诊断急性CVST的重要方法;MRI对亚急性CVST具有更高敏感度与特异性;MRV可快速、无创地评价CVST。     

脑静脉窦血栓形成的影像学检查及临床特征

目的:探讨脑静脉窦血栓形成(CVT)的临床特征及影像学特点,以寻求早期识别的征象及影像策略。方法:对62例经MR或/和DSA确诊为CVT的患者临床资料及影像学特点进行回顾性分析,并予抗凝治疗。结果:62例患者中有60例有非特异性头痛,其中56例行MRI+MRV检查确诊为CVT的有54例,32例经DSA检查均确诊为DVT。结论:CVT的临床表现缺乏特异性,MRI+MRV检查是诊断DVT的首选方法,DSA是诊断CVT的"金标准"。     

脑静脉窦血栓形成21例分析

目的 探讨脑静脉窦血栓形成(CVST)的早期诊断及治疗方法.方法 回顾性分析21例CVST患者的发病年龄、发病形式、临床表现、影像学特征及预后.结果 CVST发病年龄多在20～40岁;多数为急性或亚急性发病；早期多表现为头痛、呕吐、视盘水肿；伴或不伴有局灶性神经功能缺损或癫痫发作;影像学表现为静脉窦闭塞伴非动脉分布区多发性脑梗死,有的伴有出血；颅压明显增高,脑脊液蛋白及细胞升高.结论 认识CVST的临床特征及时行CT、MRI、MRV等检查,必要时行数字减影血管造影(DSA)检查.一旦诊断明确,应尽早选用抗凝治疗.     

脑静脉窦血栓形成诊断及治疗方法的探讨

目的探讨脑静脉窦血栓形成（CVST）诊断和治疗方法,增强对该病的认识,提高诊治水平。方法回顾性分析21例CVST患者的病因、临床表现、影像学特征、治疗方法。结果21例患者年龄16～57岁,男女比例为1：0．61。头痛、呕吐、抽搐、偏瘫为早期最常见的临床表现,最常见的病因是妊娠。磁共振血管造影（MRA／MRV）和数字减影脑血管造影（DSA）表现为一处或多处静脉窦闭塞或不完全闭塞。经脱水、低分子肝素抗凝、尿激酶局部溶栓和血管内介入治疗后,21例患者中14例（66．7％）痊愈,6例（28．6％）好转出院。结论CVST临床表现复杂多样,无特异性,容易误诊。MRA／MRV确诊阳性率高,而DSA检查是明确诊断的金标准。抗凝及强有力的脱水治疗有良好的治疗效果,血管介入治疗对改善重症CVST患者预后有重要意义。     

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.