MR T2*成像无创评估多发性硬化患者肝脏铁含量

目的 通过MR T2^*技术定量测定多发性硬化(MS)患者肝脏的铁含量,探讨MS患者肝脏铁含量是否与正常人存在差异。 方法 对35例MS患者(MS组)及17名健康志愿者(对照组)分别进行肝脏T2^*扫描,测量肝脏各段的T2^*值,并计算其平均值。结合实验室检查检测血清铁、铁蛋白水平,综合评估MS患者机体的铁负载水平。 结果 MS组与对照组肝脏平均T2^*值分别为17.46±2.82和17.17±3.69(P>0.05)。MS组中9例(9/35,25.71%)、对照组中4例(4/17,23.53%)出现铁过载,但均在可接受范围内(5.0~15.8 ms),两组铁过载发病率差异无统计学意义(χ²=0.029,P>0.05)。MS组与对照组血清铁、铁蛋白水平差异均无统计学意义(P均>0.05)。MS组及对照组的T2^*值与铁蛋白水平均呈负相关(r=-0.448,P=0.032;r=-0.742,P=0.009),与血清铁未见相关性(P均>0.05)。 结论 MS患者机体中的铁负载水平与健康志愿者无明显差异,提示MS患者脑内过度的铁沉积并非由整个机体的铁过载引起。     

IDEAL-IQ技术定量测量健康青年女性颈部锁骨上脂肪

目的 评估基于最小二乘法估计和不对称回波迭代分解的水脂分离（IDEAL-IQ）技术定量测量健康青年女性颈部锁骨上脂肪的可行性。方法 招募87名20~35岁健康青年女性,根据体质量指数（BMI）分为BMI<24 kg/m²组（n=72）和BMI ≥ 24 kg/m²组（n=15）。对受试者行IDEAL序列扫描,分别测量颈部锁骨上、胸壁、腹壁皮下脂肪及肝脏的脂肪分数（FF）及T2^*弛豫率（R2^*）值,比较两组间及锁骨上与胸壁皮下脂肪FF、R2^*值的差异,并分析FF、R2^*与BMI的相关性。结果 颈部锁骨上脂肪FF低于胸壁皮下脂肪FF值;锁骨上脂肪R2^*值高于胸壁皮下脂肪R2^*值。BMI<24 kg/m²组与BMI ≥ 24 kg/m²组间颈部锁骨上、胸壁皮下脂肪,腹壁、肝脏的FF、R2^*值及颈部/胸壁FF值、颈部/胸壁R2^*值差异均有统计学意义（P均<0.05）。颈部锁骨上脂肪FF值与BMI呈正相关（r=0.601,P<0.001）,R2^*值与BMI呈负相关（r=-0.409,P=0.001）。结论 MR IDEAL-IQ技术可定量测定颈部锁骨上与体部脂肪的差异,两者间FF及R2^*值存在差别。     

3.0T磁共振R2*值评价足月出生婴儿脑深部灰质核团年龄相关性铁沉积

目的 采用3.0T MR R2^*值观察婴儿脑深部灰质核团铁沉积与周龄的关系。方法 纳入婴儿53名,校正周龄(PMA)37~92周。采用GE 3.0T磁共振扫描仪进行增强T2^*加权血管成像(ESWAN)序列扫描,测量脑内双侧深部灰质核团(尾状核、壳核、苍白球、丘脑、红核和黑质)的R2^*值。对各部位R2^*值与脑铁含量进行相关分析,并分析R2^*值与PMA的关系。结果 婴儿期脑深部灰质核团R2^*值与脑铁含量均呈正相关(P均<0.001)。尾状核、壳核、苍白球、丘脑、红核和黑质的R2^*值与PMA均呈正相关(r=0.865、0.818、0.893、0.844、0.742和0.834,P均<0.001)。结论 婴儿期脑深部灰质核团的R2^*值随周龄增大逐渐增加,其可反映局部脑铁沉积随周龄的增加。     

MRI-T2*技术定量分析β-重型地中海贫血心脏、肝脏、胰腺铁沉积及其与糖代谢的相关性

目的 采用MRI-T2^*技术定量分析β-重型地中海贫血（β-TM）心肌、肝脏、胰腺铁沉积,观察其与糖代谢的相关性。方法 回顾性分析109例β-TM患者,其中91例于MR检查前后2周内接受空腹血糖检测,根据检测结果将其分为血糖升高组（n=19）及血糖正常组（n=72）,比较组间临床资料及MRI指标差异,分析心肌、肝脏、胰腺R2^*值（1/T2^*）与血糖代谢指标的相关性。采用Logistics回归分析糖代谢异常的危险因素,绘制心肌、肝脏、胰腺R2^*预测血糖升高的受试者工作特征（ROC）曲线,评价其诊断效能。结果 109例β-TM患者心肌T2^*值27.72（15.87,31.16）ms,肝脏T2^*值1.71（1.34,3.07）ms,胰腺T2^*值6.09（3.76,15.02）ms。血糖升高组与血糖正常组间年龄、输血年限、总输入铁量、去铁年限、空腹血糖、胰岛素抵抗指数、心肌R2^*及胰腺R2^*差异均有统计学意义（P均<0.05）。心肌及胰腺R2^*均与空腹血糖呈正相关（r=0.36、0.41,P均<0.01）,肝脏R2^*与空腹血糖无明显相关（P=0.76）。肝脏R2^*、胰腺R2^*均为糖代谢异常危险因素（P均<0.05）。心肌及胰腺R2^*预测空腹血糖升高的曲线下面积（AUC）均为0.80（P均<0.01）。结论 心肌、胰腺铁沉积与β-TM血糖代谢存在一定相关性;心肌和胰腺R2^*预测β-TM血糖升高的诊断效能佳。     

肝、脾及腰椎R2*值评估慢性肾衰竭患者体内铁含量

目的 观察肝、脾及腰椎R2^*值用于评估慢性肾衰竭(CKD)患者体内铁含量的价值。方法 回顾性纳入52例CKD患者,根据转铁蛋白饱和度≤20%与否分为绝对缺铁组(n=22)和非绝对缺铁组(n=30)。基于改良Dixon定量(mDIXON-quant)MRI观察组间肝、脾及腰椎R2^*值差异,并分析上述R2^*值与铁代谢指标的相关性;行logistic回归分析,观察绝对缺铁的影响因素,并分析其诊断效能。结果 绝对缺铁组与非绝对缺铁组脾和腰椎R2^*值差异均有统计学意义(P均＜0.05)。CKD患者脾、腰椎R2^*值与铁蛋白、转铁蛋白饱和度均呈正相关(P均＜0.05),与不饱和铁结合力、总铁结合力及转铁蛋白呈负相关(P均＜0.05)。腰椎R2^*值减低是CKD患者绝对缺铁的影响因素(P＜0.05)。以腰椎R2^*值=134.26 Hz为最佳截断值,其诊断CKD患者绝对缺铁的敏感度为86.70%,特异度为68.20%,曲线下面积为0.727。结论 腰椎R2^*值有助于评估CKD患者体内铁含量。     

输血依赖性疾病多脏器铁沉积MRI量化分析

目的 探讨MRI T2^*Map评价输血依赖性疾病患者多脏器铁沉积的价值。方法 收集输血依赖性疾病患者30例,按输血量分为未输血组(n=7)、少量输血组(3年内累计输血量1~150 U,n=13)和大量输血组(3年内输血量>150 U,n=10);收集同期健康志愿者28名(正常组)。采用3.0T MR多回波梯度回波序列获得肝脏、心脏、胰腺的T2^* Map,比较组间同器官T2^*值,分析不同器官T2^*值的相关性及T2^*值与血清铁蛋白(SF)、输血量的相关性。结果 正常组和未输血组肝脏T2^*值高于少量输血组(q=13.23、12.29)与大量输血组(q=13.10、12.23);正常组和未输血组胰腺T2^*值高于少量输血组(q=4.23、3.63)与大量输血组(q=7.14、5.88),少量输血组高于大量输血组(q=2.54);正常组、未输血组心脏T2^*值高于大量输血组(q=2.29、3.11);差异均有统计学意义(P均<0.05)。心脏与胰腺T2^*值呈正相关(r=0.542,P=0.017),心脏、胰腺与肝脏T2^*值均无明显相关性(r=0.32、0.65,P>0.05)。肝脏T2^*值与SF呈中度负相关(r=-0.503,P=0.028),心脏、胰腺T2^*值与SF无明显相关性(r=-0.30、-0.61,P>0.05);肝脏、胰腺T2^*值与3年内输血量呈中度负相关(r=-0.528、-0.793,P均<0.01),心脏T2^*值与3年内输血量无明显相关性(r=-0.252,P=0.246)。结论 输血依赖性疾病患者铁最早沉积于肝脏,胰腺、心肌次之;MRI T2^* Map可直接、可靠地检测各器官的铁沉积水平。     

双回波序列和1H-MRS检测非酒精性脂肪肝大鼠肝内脂肪含量

目的 探讨双回波序列和¹H-MRS在非酒精性脂肪肝(NAFLD)大鼠肝内脂肪含量测定中的应用价值。方法 对25只NAFLD SD大鼠首先行双回波序列扫描和¹H-MRS检查,并测定肝内脂肪含量,再行组织病理学检测,分析双回波序列与¹H-MRS、组织病理学结果的相关性。结果 双回波序列与¹H-MRS所测肝内脂肪含量呈正相关(r=0.936,P<0.001);双回波序列与组织病理学所测肝内脂肪含量呈正相关(r=0.946,P<0.001),Bland-Ahman曲线分析显示双回波序列和病理学测定的大鼠肝内脂肪含量一致性非常好。结论 双回波序列测定NAFLD肝内脂肪含量简便、易行,且准确性高,有望取代组织病理学检查。     

3.0T磁共振T2* mapping成像诊断腰椎间盘退变

目的 评价T2^* mapping成像技术在诊断腰椎间盘退变中的临床应用价值。方法 对12例下腰痛患者(症状组)及12名无症状志愿者 (对照组)行腰椎间盘MR扫描,在L₁-S₁共120个椎间盘放置ROI,测量相应的T2^*值,并按Pfirrmann标准对常规 T2WI显示的椎间盘进行分级,分析并比较症状组和对照组腰椎间盘内T2^*值的差异,对T2^*值与椎间盘分级间的相关性采用Spearman相关分析。结果 症状组椎间盘Pfirrmann分级平均得分高于对照组(t=5.04,P<0.05)。症状组腰椎间盘平均T2^*值为(76.90±33.10)ms,低于对照组[(116.00±71.60)ms,P<0.05]。症状组和对照组T2^*值均与Pfirrmann分级呈负相关(r=-0.84、-0.76,P均<0.05)。结论 T2^* mapping成像技术能为影像学量化诊断腰椎间盘退变提供依据。     

BOLD-MRI评价2型糖尿病患者降血糖治疗前后肾组织氧合状况

目的 采用BOLD-MRI评价糖尿病患者降血糖治疗前后肾组织氧合水平改变情况及其与血糖水平的相关性。方法 对23例2型糖尿病患者（糖尿病组）于降血糖治疗前后及23名健康志愿者（对照组）行肾脏BOLD-MRI,测量肾脏皮、髓质R2^*值,并进行统计学分析。结果 糖尿病组降血糖前、降血糖后及对照组肾皮质的R2^*值均低于肾髓质（P均<0.001）。糖尿病组降血糖前肾髓质R2^*值高于降血糖后和对照组（P均=0.001）,降血糖后肾髓质R2^*值与对照组差异无统计学意义（P=0.941）。糖尿病组降血糖前、降血糖后、对照组间肾皮质R2^*值差异无统计学意义（P=0.572）。糖尿病组肾髓质R2^*值与血糖值呈正相关（r=0.365,P=0.002）,而肾皮质R2^*值与血糖值无明显相关性（r=-0.014,P=0.908）。结论 降血糖治疗可以改善肾髓质的氧合状况;BOLD-MRI可用于评价糖尿病患者降血糖治疗前后肾组织氧含量的变化。     

磁共振血氧水平依赖成像观察原发性肝细胞癌高强度聚焦超声治疗前后氧摄取变化特点

目的 通过观察原发性肝细胞癌(HCC)高强度聚焦超声(HIFU)治疗前后氧摄取变化特点,探讨BOLD MRI评估HIFU治疗原发性HCC疗效的潜在价值。方法 16例原发性HCC患者于HIFU治疗前及治疗后2周内接受常规MRI、BOLD MRI及动态增强扫描。BOLD MRI采用梯度回波序列。将BOLD图像数据传输至工作站,采用R2^*软件对图像进行后处理生成R2^*图及T2^*图。在病灶中心、周围正常肝组织以及背部肌肉设置ROI,测量R2^*值、T2^*值及信号强度(SI)。对3个ROI R2^*值、T2^*值及SI在HIFU治疗前后的差异进行比较。结果 与治疗前比较,HCC R2^*值在HIFU治疗后2周内明显升高 ,而T2^*值、SI值在HIFU治疗后2周内明显降低 。周围肝组织及背部肌肉R2^*值、T2^*值及SI值在HIFU治疗前后的无明显变化(P＞0.05)。结论 BOLD MRI在评价原发性肝细胞癌缺氧及HIFU疗效方面有一定潜力。     

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.     

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.     

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.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.