原发性肝脏血管肉瘤的CT及MRI表现1例

患者男,58岁,间断性右上腹胀痛半年,伴体重减轻入院.既往健康,无肝炎及肝硬化病史.体检:肝区压痛,未触及肿块.实验室检查:HBs Ag(-),AFP、CEA及CA19-9均正常. CT:平扫见肝右叶7 cm×5 cm×4 cm低密度肿块;增强扫描肝动脉期病灶中心斑点状强化,门静脉期和平衡期病灶边缘结节状强化(图1).MR:T1WI呈高低混杂信号,肿块中心斑片状高信号(图2),T2WI呈不均匀明显高信号(图2):增强扫描动脉期肿块中心呈斑点状强化,门静脉、平衡期及延迟扫描增强消退呈低信号,肿块边缘逐渐明显强化.     

儿童脑干伴多层菊形团形成的胚胎性肿瘤1例

<正>女性患儿，3岁，走路不稳3天，既往体健。查体：神志清，反应差，颈软无抵抗，四肢肌力、肌张力减弱。头颅CT：脑干左侧稍高密度为主囊实性病灶，边界清晰，鞍上池受压变形。头颅MRI：中脑及脑桥左侧31mm×38mm×31mm肿块，边界清晰，呈T1WI低信号、T2WI稍高信号（图1A）,T2液体衰减反转恢复序列呈等低信号，弥散加权成像（diffusion weighted imaging,DWI）部分受限（图1B），表观弥散系数（apparent diffusion coefficient,ADC）图呈低信号（图1C）,     

2例眼眶结节性肌筋膜炎MRI表现

<正>病例1：患者男,47岁,左眼及头部胀痛10天,外院CT提示左眶肿物;既往体健。查体：左侧上眼睑红肿,左眼球轻度突出,眶周无异常隆起,眼球运动正常。MRI：左眶肌锥内间隙颞侧缘眼球后方2.4cm×1.4cm×1.8cm类卵圆形病灶,边界清,呈T1WI稍高信号（图1A）,T2WI中心高信号、边缘等信号（图1B）,压迫视神经眶内段及下直肌;增强后病灶呈环形渐进性强化（图1C）;诊断为左眶内占位,良性可能性大。     

超声诊断肢端雀斑样黑色素瘤并皮下转移1例

<正>患者女，75岁，因发现左大腿内侧肿块6个月余入院。体格检查：左大腿中段内侧见一皮下肿块，触压痛明显，活动性欠佳，与周围组织粘连明显；左足第五趾远端跖侧皮肤发黑，脚趾末端见一灰黑、灰白色肿块，质韧，边界不清晰，触痛明显，无活动度（图1A）。超声检查：左大腿内侧脂肪层内见一大小约5.4 cm×5.3 cm×3.5 cm团状低回声肿块（图1B），呈分叶状；CDFI于其内探及丰富血流信号，阻力指数（RI）为0.83（图1C）。左足第五趾远端软组织内见一大小约1.5 cm×1.2 cm×1.0 cm不均质低回声肿块，形态不规则，边界不清晰，向关节深部浸润，     

遗传性结节性硬化病超声表现一例

患者女,21岁,傣族.以"产后间断性发热1个月伴阴道出血十余天"为主诉入院.入院后进行常规超声检查,第1次超声报告为"双肾增大伴双肾实质多发高回声团,建议进一步检查".据此将患者转入泌尿外科,行CT检查.CT示(图1):(1)双肾病变:①恶性占位性病变,肾癌或脂肪肉瘤;②以平滑肌及血管为主的错构瘤;(2)左肾轻度积水;(3)双侧髂骨、骶骨(骶髂关节弯)及T12、L1-5椎体骨质密度增高灶,成骨性转移待排除.3 d后对其行第2次超声检查,超声示:双肾体积明显增大、形态异常,右肾大小13.7 cm×6.5 cm×4.7 cm,左肾大小14.9 cm×7.2 cm×5.1 cm.双肾实质内可见较多大小不等的高回声与低回声肿块,肿块间尚可见少许正常肾脏组织回声,肿块以高回声为主,形态尚规则,肿块边界清、内部回声尚均匀,但较大高回声肿块内可见不规则无回声区;高回声肿块内未见明显血流信号,较大低回声肿块内可见较丰富血流信号(图2);右肾内最大高回声肿块大小约4.8 cm×2.9 cm,最大低回声肿块大小约3.6 cm×2.7 cm,均位于右肾上极;左肾内最大高回声肿块大小约3.2 cm×2.7 cm,位于左肾上极;最大低回声肿块大小约6.5 cm×4.1 cm,位于左肾下极.另于左、右肾各见一无回声区,均位于双肾的中上部,大小分别约1.4 cm×1.2 cm和1.7 cm×1.5 cm.     

盆腔侵袭性血管黏液瘤1例

病例女,43岁,健康体检时B超发现盆腔肿块而收入院。平素体健,无明显腹部症状,实验室检查基本正常。MRI检查发现：盆腔左侧见6.2cm×8.2cm×8.3cm的不规则软组织肿块,T1WI呈低信号,T2WI呈明显高信号,信号不均匀,可见纵行的条索状结构,T2W-SPAIR呈高信号,     

MRI诊断左小腿促结缔组织增生性小圆细胞肿瘤一例

<正>患者女,27岁,发现左小腿渐进性增大肿物1个月余入院。于入院前1个月患者无明显诱因出现左小腿外侧肿痛,站立时间较长、行走久时症状明显,无低热、盗汗、夜重昼轻等不适,与天气变化无关,仍可行走及锻炼。MRI检查:左小腿上段偏外侧软组织可见不规则分叶状软组织肿块,T1WI呈稍低信号(图1A),T2WI呈混杂低信号,内部见斑点状稍高信号(图1B),T2脂肪抑制相肿块呈混杂信号(图1C),范围约4.3 cm×     

读片窗

病例男,３７岁。间歇性头痛半年,抽搐２次。查体：右侧上下肢肌力二级。CT检查：CT平扫见前颅凹及额部不规则形不均匀高密度肿块（图１）。增强CT,见肿块略呈均匀强化,有粗大的血管供血,边缘呈分叶状,大小约１０cm×９cm,周围少许低密度水肿区,双侧侧脑室显示不清（图２）。MR检查：矢状面T１WI,见肿块呈均匀低信号区,其边缘与颅底、前、中颅凹及脑组织分界不清（图３）。T２WI肿块呈不均匀高信号区,其内可见血管流空信号,肿块偏左侧生长,向后累及胼胝体、三脑室及下丘脑（图４）。请分析本案例,答案见４２３页。读片窗…     

1例肝脏原发性去分化脂肪肉瘤超声造影表现

<正>患者女，51岁，体检发现右上腹占位2个月；既往无特殊病史。查体：腹膨隆，右上腹扪及直径约15cm质硬包块，活动度差。实验室检查未见明显异常。超声：肝右叶15cm×12cm杂乱回声肿块，形态较规则，边界不清，内部及周边见数个斑片状强回声（图1A）；超声造影见动脉期肿块呈不均匀高增强（图1B），门脉期及延迟期相强化程度逐渐减低，下份见片状无增强区（图1C）；考虑肿瘤性病变，     

横结肠系膜巨大黏液样脂肪肉瘤超声表现1例

<正>病例女，36岁，因“间断腹痛1周”来我院就诊。患者曾于外院行腰骶部未分化小圆细胞恶性肿瘤切除术，术后化疗持续12月。后因感腰酸及腰骶部皮肤麻痛感返院治疗及复查，查腰骶部MRI提示病情稳定。查体：自剑突下至耻骨联合上缘可触及一个肿物，大小约17 cm×15 cm，质韧，无明显压痛及反跳痛。实验室检查：肿瘤相关抗原125 49.3 U/mL。超声检查：腹腔内探及17 cm×15 cm×9 cm不均质回声肿块，椭圆形，界清，内部回声不均匀，边缘以低回声为主，散在不规则无回声区，中央以高回声为主，肿块后方回声稍增强（图1,2）；彩色多普勒显示其内条状血流信号（图3）。超声造影：腹腔内不均质回声肿块于13 s开始增强，     

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.