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病例男,9岁。以“精神异常,行为失常,伴听力下降月余”为主诉来诊。CT检查:双侧侧脑室后角内侧可见条形低密度影,呈“八”字分布,双侧脑室后角周围可见对称性片状高密度钙化影。其余脑实质内未见异常密度影,灰白质界限清晰,脑室系统等大对称,中线结构居中(图1～3)。MRI检查:双侧侧脑室后角周围见形态不规则大片状异常信号,T1WI示异常信号中心呈极低信号,周围呈高信号,最外围为低信号;T2WI表现为片状高信号,中心为更高信号;所示病变范围较T1WI增大,矢状面示胼胝体压部亦受累,呈均匀一致长T1信号(图4～6)。血生化学检查:血中极长链饱和…     

脑内脱髓鞘假瘤1例

患者女,57岁.主因"左侧面部抽搐16个月,左侧肢体乏力伴智力下降4个月,抽搐次数增多1个月"入院.查体:口角向右歪斜,左侧肢体肌力5级.头颅MR检查示右侧额叶、双侧胼胝体额部及体部可见团片状及片状异常信号,病变边界较清,信号欠均匀,TlWI呈稍低信号,T2WI呈稍高信号,DWI上局部呈较高信号(图IA);增强扫描病变无明显强化(图1B),占位效应不明显,邻近脑回增粗、脑沟变窄.     

MRI诊断非出血性胼胝体损伤

目的 探讨MRI对于非出血性胼胝体损伤的诊断价值.方法 对23例胼胝体损伤患者的临床及MRI资料进行回顾性分析.结果 在23例非出血性胼胝体损伤灶中,膝部损伤5例,体部损伤11例,膝部与体部同时损伤6例,压部1例.MRI表现主要为胼胝体区斑点状、小片状异常信号区;T1WI呈低信号,T2WI呈高信号,FLAIR呈高信号.结论 MRI是诊断非出血性胼胝体损伤最佳的影像学手段.     

咽旁间隙海绵状血管瘤一例

病例资料患者,女,46岁,因颈背部疼入院。体格检查:双侧扁桃体Ⅰ°大,右侧软腭较左侧膨隆低垂,无明显疼痛。口咽部MRI平扫加增强示右咽旁间隙内团块状T1WI等信号(图1a)、压脂T2WI高信号(图1b),其内信号不均,见多发条状T1WI及压脂T2WI低信号影,病灶周围见环形压脂T2WI低信号影,DWI(b=800)呈高信号。     

儿童轻微脑炎/脑病伴可逆性胼胝体压部病变临床与MRI表现

目的探讨儿童轻微脑炎/脑病伴可逆性胼胝体压部病变(MERS)临床表现与MRI表现。方法回顾性分析本院14例MERS患儿的临床特点、影像学表现。结果本组14例中,男6例,女8例,年龄7个月～11岁8个月,平均为2.5岁。所有患儿均行MRI检查,首次MRI扫描距发病时间为1～7 d,平均4.3 d;复查时间间隔为7～45 d,平均14.2 d。其改变均累及胼胝体压部,病灶特征呈圆形及卵圆形,边界清晰,信号均匀,T_1WI呈等信号或稍低信号,T_2WI呈稍高信号,FLAIR为稍高信号,DWI呈明显高信号,ADC呈低信号,无水肿及占位征像。其中12例为MERSⅠ型:DWI显示胼胝体压部孤立性病变,另外2例为MERSⅡ型:其中1例病变累及胼胝体膝部,1例累及至双侧半卵圆中心白质。结论 MERS在MRI上表现为主要累及胼胝体压部孤立性可逆性改变,MRI对其早期诊断、鉴别诊断及诊疗具有较大价值。     

稽留流产MRI误诊为黏膜下子宫肌瘤变性1例

患者女,35岁,因“无明显诱因出现月经淋漓不尽3月余”入院.查体:子宫增大如孕8周.实验室检查:血绒毛膜促性腺激素1.76 mIU/ml.超声:子宫实性占位,肌瘤变性.MRI:子宫明显不均匀增大,宫腔内见约5.13 cm×4.62 cm类圆形异常信号,T1WI呈等低信号,其内见部分高信号(图1),T2WI呈低信号,其内夹杂线状、片状明显高信号(图2);增强后无强化(图3).     

MRS结合立体定向活检诊断颅内深部低级别胶质瘤1例

<正>1病例报告患者,女,66岁,入院前半年开始出现左上肢活动受限。入院时查体:神清语明,左侧瞳孔直径约2.5mm、对光反射存在,右侧瞳孔直径约3.0mm、形状不规则、对光反射无,左上肢肌力4级,双侧病理反射未引出。头部MR平扫+增强影像显示:右侧基底节、放射冠、额顶叶、胼胝体压部可见片状长T1长T2信号影,边界不清,Flair呈高信号,增强扫描     

脊髓纵裂1例

患者女,24岁,车祸致腰背部疼痛伴下肢麻木3h入院。查体:胸腰段棘突压触及扣击痛,双下肢运动可,躯干无明确感觉障碍平面,足背动脉搏动好,双侧股四头肌、胫前肌、拇长伸肌、小腿三头肌肌力为Ⅴ级,肌张力不高,双膝、跟腱对称,巴氏征及克氏征未引出。X线片示:胸11、12椎体呈楔行改变,建议进一步检查除外骨折。CT示:胸10~12椎体形态异常,前后径小,椎体及附件未见骨折,胸11椎体前缘见裂隙影,周围见骨质硬化(图1),椎管内见平行排列的两个圆形软组织密度影。MRI示:胸9、11、12椎体形态不规则,胸11椎体见异常信号影,T1WI、T2WI均呈低信号,FST2…     

颅内多发少突胶质细胞瘤1例

<正>患者男，53岁，头晕伴双下肢不适半个月；既往体健。查体及实验室检查均无明显异常。头颅CT:鞍上池、第四脑室及双侧侧脑室周围多发稍高密度结节，较大者约19 mm×11 mm, CT值43 HU,边界清楚，密度均匀(图1A)。头颅MRI:鞍上池、第四脑室、胼胝体膝部及双侧侧脑室周围见多发结节状异常信号，呈T1WI稍低(图1B)、T2WI稍高信号；     

成人低血糖脑病的MRI表现

目的 探讨成人低血糖脑病的MRI表现特征.方法 回顾性分析15例临床明确诊断为低血糖脑病患者的MRI表现;其中男6例,女9例;年龄34～79岁,平均53.8岁;全部患者行均进行常规MR序列(包括T1WI、T2WI、T2 FLAIR)和DWI检查.结果 15例低血糖患者颅脑MRI图像均发现异常信号,表现为斑片状、条状或脑回样;T1WI呈低信号,T2WI呈高信号,DWI呈明显高信号.病灶主要累及胼胝体压部、基底节、海马、黑质和大脑皮层,单侧或双侧对称性发病;其中胼胝体压部受累4例,基底节5例,单独累及尾状核头部1例,同时累及基底节、黑质、海马及大脑皮层5例.经治疗2周后3例复查MRI,病灶有明显吸收好转.结论 成人低血糖脑病发病部位及MRI信号表现具有一定的特征性,结合临床病史,可符合低血糖脑病的MRI表现;DWI序列对病灶非常敏感,呈高信号,应作为MRI检查首选序列.     

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.     

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.     

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.