脂肪肝CT、MRI定量诊断的对照实验研究

目的:探讨肝脏脂肪含量与肝脏、肌肉CT值比、肝脏CT值及脂肪抑制前后肝脏信号强度衰减率之间的相关关系及相关强度。方法:对正常组和随机抽取的2 3只实验组家兔行肝脏CT平扫及化学饱和法脂肪抑制前后肝脏MRI(SE序列,T1WI) ,测得肝脏CT值、竖脊肌CT值,计算肝脏、肌肉CT值比及脂肪抑制前后肝脏信号强度衰减率。对实验动物的肝脏进行组织学检查,并用显微图像分析仪测定肝中脂滴占肝脏单位体积的百分比(Vv 值)。结果:肝脏肌肉CT值比值与Vv 值之间存在有意义的高度线性负向相关关系(r =- 0 .896 ,t =- 10 .2 89,P <0 .0 0 1) ;肝脏CT值与Vv 值之间存在有意义的中度线性负向相关关系(r =- 0 .818,t =- 7.2 4 9,P <0 .0 0 1) ;脂肪抑制前后肝脏信号强度衰减率与Vv值之间存在有意义的中度线性正相关关系(r =0 .5 5 6 ,t =3.4 0 7,P =0 .0 0 2 )。结论:肝脏肌肉CT值比值较肝脏CT值绝对值、脂肪抑制前后肝脏信号强度衰减率具有与Vv 值更高的相关强度,该指标可望用于活体无创估计肝脏脂肪含量。     

MR DWI对急性胰腺炎的诊断价值

目的 探讨MR扩散加权成像(DWI)对急性胰腺炎(AP)的诊断价值.方法 回顾性分析50例AP及75例正常胰腺的MR资料,计算DWI序列b=800 s/mm2图像上胰腺与肝脏的信号强度比(SIR),测量胰腺的表观扩散系数(ADC),分别比较2组的SIR及ADC,并根据受试者工作特征(ROC)曲线确定最佳诊断阈值,评价SIR、ADC与MRI常规序列的诊断效能.结果 与正常胰腺相比,AP组SIR显著升高(2.06±0.48 vs 1.24±0.27,t=12.2,P<0.0001),ADC显著降低[(991±133)μm2/s vs(1153±149)μm2/s,t=-6.2,P<0.0001].最佳诊断阈值分别为SIR>1.51、ADC≤1039μm2/s.SIR的敏感度(92.0%)高于ADC(72.0%)及MRI常规序列(74.0%),SIR(88.0%)及MRI常规序列(93.3%)的特异度高于ADC(77.3%).结论 AP时水分子扩散受限,SIR诊断效能优于ADC及MRI常规序列,有利于AP的检出.     

背景信号抑制磁共振弥散加权成像对急性胰腺炎的诊断价值

目的 探讨背景信号抑制磁共振弥散加权成像(diffusion weighted imaging with background signal suppression,DWIBS)检查对急性胰腺炎的诊断价值.方法 对81例急性胰腺炎患者及93例正常对照组进行常规MRI和DWIBS检查,测量DWIBS图像上胰腺及肝脏的信号强度,计算胰腺与肝脏的相对信号强度比(SIR).结果 DWIBS显示急性胰腺炎患者胰腺的信号强度明显高于肝脏(SIR=2.38),正常对照组的胰腺与肝脏信号相似(SIR=1.33),两者差异具有统计学意义(t=-17.889,P<0.01).SIR值的ROC曲线分析显示,DWIBS序列的曲线下面积0.983,当诊断界值SIR> 1.67时灵敏度为93.83%,特异度为91.4%,Youden指数0.85.预设的DWIBS专用窗位30,窗宽60有助于病变的显示.常规MRI检查的阳性率为88.9%,DWIBS检查的阳性率为97.5%(P<0.05).结论 DWIBS结合常规MRI检查可明显提高急性胰腺炎的检出率.     

术前CT血管成像对肝移植脾动脉盗血综合征的预估

目的 评价术前CT血管成像对肝移植术后脾动脉盗血综合征的预估价值.方法 脾动脉盗血组(A组)及正常对照组(B组)各8例行CT血管成像.应用GE ADW4.2工作站,测量脾动脉盗血组和正常组病人肝移植术前肝动脉直径,脾动脉直径,肝脏体积,脾体积及其比值.使用SPSS 13统计软件,对2组数据进行统计分析.结果 脾动脉盗血组和正常组脾动脉直径在统计学上有显著的差别(P=0.008,P<0.05);脾动脉与肝动脉的比值在统计学上亦有显著性差别(P=0.015,P<0.05);而肝动脉直径、脾体积、肝脏体积、脾体积/肝脏体积统计学上无显著性差别(P值分别为0.364,0.78,0.624,0.172,P>0.05).结论 脾动脉直径、脾动脉直径/肝动脉直径对术后是否发生盗血具有重要提示意义,并且脾动脉直径＞7.5 mm、脾动脉直径/肝动脉直径＞1.2提示发生盗血的概率较大.     

扩散加权成像区分肺良恶性病变的价值

目的:探讨磁共振扩散加权成像(DWI)在肺部良恶性结节或肿块中的鉴别诊断价值.方法:58例经病理或临床随访证实的肺部结节或肿块患者行常规MRI和DWI扫描(b=0,300,600,900,1200s/mm2),比较病灶同层面两种参照物(胸髓和胸壁肌肉)条件下病灶信号强度的差异,并评价肺病灶良恶性DWI诊断敏感性、特异性和准确性.评价采用5分制,统计采用两样本t检验和ROC曲线来比较良恶性病变的信号强度差异和诊断效能.结果:以肌肉为参照诊断良恶性病变的ROC曲线下面积(0.738)与以胸髓为参照时的曲线下面积(0.701)无统计学显著差异(P=0.3095).以胸壁肌肉为参照时的肺癌组DWI的信号强度评分(4.34±0.97)显著高于良性病变组(3.25±1.37,P=0.0036);以病灶信号强度等于或大于肌肉信号强度作为判断良恶性病变的界值,其诊断敏感性、特异性和准确性分别为81.58%、45.00%、75.86%.结论:DWI的信号强度有助于肺部良恶性病变的鉴别诊断.以胸壁肌肉为参照的DWI具有较高的诊断敏感性和准确性,但特异性尚有欠缺,DWI可能成为一种肺癌诊断和鉴别诊断的辅助技术手段.     

脂肪抑制FSPGR序列:胰腺病变定量和定性分析的ROC曲线评价

目的利用ROC曲线评价平扫脂肪抑制FSPGR序列检出胰腺疾病的准确性。方法对92例研究对象行脂肪抑制FSPGR序列扫描,其中57例正常胰腺,35例异常胰腺,测量RO I的信号强度,并计算胰腺相对于肝脏、脾脏的信号强度比值,然后进行定性评价。结果相对于肝脏或者脾脏的信号强度,正常和异常胰腺之间的相对信号强度存在差异。并且胰腺相对于肝脏、脾脏ROC曲线下的面积分别为0.92±0.03、0.91±0.04。与肝脏相比较,对胰腺的定量与定性评价无显著性差异,定性分析检出胰腺病变的敏感性为86.7%,特异性为91.2%。结论在鉴别正常和异常胰腺方面,定性判断与定量分析一样精确,且两者均能够检出胰腺的病变。     

超顺磁性氧化铁MR成像评估大鼠非酒精性脂肪肝炎枯否细胞功能的初步研究

目的 初步探讨超顺磁性氧化铁(SPIO)作为MRI对比剂评估大鼠非酒精性脂肪肝炎(NASH)枯否细胞(KC)功能的可行性.方法 20只雄性SD大鼠按完全随机法分为实验组和对照组,每组10只,实验组喂养高脂饲料,对照组喂养普通饲料.8周后对所有大鼠行肝脏MRI及SPIO增强扫描,计算肝脏组织平均信号强度下降百分比(PSIL)和SPIO增强前后肝脾对比信号强度比值(RSIR),测定血清总胆固醇(TC)和甘油三酯(TG)值,并取肝脏标本行HE和普鲁士蓝染色分析病理表现.采用两组独立样本均数t检验比较2组不同序列SPIO增强后PSIL和RSIR值的差异.结果 实验组1只大鼠因麻醉过深死亡,其余9只血清TC及TG值分别为(6.58±1.25)和(1.53±0.23)mmoL/L,较对照组[分别为(1.64±0.22)和(0.55±0.14)mmol/L]均明显升高(t值分别为11.716和11.588,P值均＜0.01).SPIO增强扫描后两组肝实质信号强度在各序列明显下降,在PDWI及T_1WI上实验组PSIL分别为(34.78±4.51)%和(60.38±3.49)%,较实验组[分别为(64.96±2.42)%和(81.08±1.66)%]小,差异有统计学意义(t值分别为-18.451和-16.240,P值均＜0.01).PDWI、T_2WI、T_2~*WI和T_1WI序列实验组RSIR分别为1.002±0.141、5.000±0.516、20.004±1.490和2.601±0.077,均较对照组(0.400±0.102、1.500±0.115、0.503±0.105和-0.300±0.058)大(t值分别为10.745、19.800、39.168和92.785,P值均＜0.01).实验组肝脏组织中普鲁士蓝染色阳性颗粒积分(2.33±0.50)分较对照组(4分)明显减少(t=-10.000,P＜0.01).结论 高脂饮食诱导的SD大鼠NASH模型接近人类发病情况且容易建立,临床应用型1.5 T MR通过SPIO增强肝脏扫描可评估KC的功能,提示NASH的发病机制与KC功能的下降有关.     

经颈静脉肝内门体分流术后肝脏及相关脏器时间-密度曲线变化的临床意义及价值

目的 探讨经颈静脉肝内门体分流术(TIPS)后肝脏及相关脏器时间-密度曲线(TDC)变化的临床意义及价值. 方法 对拟行TIPS的20例肝硬化患者于术前2～3天、术后1周分别行肝脏灌注扫描.记录并观察第一肝门下方(TIPS支架下端)门静脉主干层面门静脉、肝实质、脾实质等3个感兴趣区的TDC形态、达峰时间(TTP)和峰值(PV)的变化情况.结果 与TIPS术前比较,术后门静脉、肝脏、脾脏TTP提前(t/Z=3.322、2.242、-2.298,P=0.004、0.037、0.022)和门静脉PV增高(t=-2.613,P=0.017),差异有统计学意义;肝实质PV降低(t=1.137,P=0.270),脾脏PV升高(t=1.137,P=0.144),差异无统计学意义.脾脏TDC由术前的速升缓降型、缓升平台型、持续缓升型转变为术后速升缓降型.结论 门静脉、肝实质、脾实质TDC变化可直观地反映TIPS术后肝脏血流动力学变化特点.     

Gd- DTPA对肝脏、脾脏及肾脏1.5T MR弥散加权成像的影响

目的:探讨钆喷酸葡胺(Gd-DTPA)在1.5T MR机对正常肝脏、脾脏、肾脏弥散加权成像(DWI)的影响.方法:30例健康体检者在1.5T MR机做上腹部MRI.除常规MR平扫和增强外,在增强前和增强后7min采用b值=500 s/mm2单次激发自旋回波平面成像序列(SE- EPI)分别行DWI扫描.测量增强前后肝脏、脾脏、肾脏在DWI上的信噪比(SNR)、脾脏-肝脏对比噪声比(CNR)、信号强度值和ADC值,并进行统计分析.结果:30例健康体检者检查结果均正常.正常肝脏、脾脏DWI的SNR、CNR、信号强度值、ADC值增强后7min与增强前比较差异无统计学意义(P＞0.05),肾脏DWI SNR、信号强度值、ADC值增强后7min较增强前降低,差异有统计学意义(P＜0.05).结论:Gd-DTPA增强后7min对肝脏、脾脏DWI的图像质量和ADC值无明显影响,而肾脏DWI的图像质量和ADC值降低.     

胰腺异位副脾的影像学诊断(附3例报告并文献复习)

目的:探讨胰腺异位副脾(IPAS)的CT和MRI诊断价值.方法:回顾性分析经手术病理证实的3例IPAS患者的病例资料.其中1例行CT平扫和增强检查,2例行MRI平扫和动态增强检查.结果:3例胰腺异位副脾均位于胰尾,主要表现为信号强度或密度与脾脏相似,增强后病灶均匀强化,与脾脏实质强化程度相似;3例同时伴有脾门区副脾.结论:IPAS为胰腺少见病变,其发生部位及CT和MRI表现具有一定特征性.     

Optimization of the system of medical service of students of Cadet Schools of the Ministry of Defense of the Russian Federation

One of the factors of the successful military career guidance Cadet schools students is preserving and promoting their health. Medical support of children and adolescents aged 10-17 years should include the full range of medical and preventive measures defined for this group. The state of providing outpatient care for pupils at the Cadet School in St. Petersburg was studied. These results show that full medical care in accordance with the standards can be based only on children's health clinics. It is important that the organization of medical support pupils cadet schools should be cooperate with civilian health care.     

带状疱疹83例误诊原因分析

带状疱疹是由水痘—带状疱疾病毒引起的皮肤科常见疾病。其主要的病理损害,一是受累神经的严重炎症性浸润,继而导致受侵犯神经节内神经细胞变性、坏死;二是皮肤的水泡。迅速抑制神经节和相应的感觉神经纤维的充血、水肿和坏死,防止粘连形成,达到迅速镇痛、改善皮损,缩短病程及防止后遗症的发生是治疗的关键。因而,尽早明确诊断,     

Estimation of accumulated dose of radiation by method of ESR-spectrometry of dental enamel of mammals

ESR-spectrometry was used to investigate radiation-induced paramagnetic centers in enamel of mammals: carnivores (polar bear and fox), ungulates (reindeer, European bison, moose), and man. Values at half the microwave power saturation of the radiation signal, P_1/2, evaluated at room temperature, was found to range from 16 to 26 mW for animals and man. A new approach to discrimination of the radiation induced signal from the total ESR spectrum of reindeer enamel is proposed. ‘Dose-response’ dependencies of enamel of different species mammals were measured within the dose range from 0.48 up to 10.08 Gy. Estimations of ‘radiosensitivity’ enamel of carnivores and ungulates showed good agreement with radiosensitivity enamel of man by ESR method.     

Analysis of the results of the international comparison of activity measurements of a solution of Fe

The results of an international comparison of activity measurements of a solution of ⁵⁵Fe organized by the BIPM in 2005 are reported and analysed. This exercise, which follows the procedures of the CIPM mutual recognition arrangement to update older comparisons, is a renewal of the comparison organized by the BIPM that took place in 1978. A EUROMET comparison was organized in 1996 specifically to compare activity measurements of a ⁵⁵Fe solution by means of liquid-scintillation techniques. Results of these three comparisons are presented and discussed in this paper.

The radionuclide solution was provided by the NPL, which also distributed the samples to the participants. The activity of the ampoules was measured by 16 laboratories using 12 methods producing 25 results. Some general considerations on uncertainty assessments pertaining to the different techniques used are drawn. The outcome of four different estimators is compared from which the presence of at least one outlier can be confirmed. Further measurements should be made to try to reduce the discrepancy between the results. To date the outcome of the present comparison does not show an improvement to that of the 1996 comparison.     

Evaluation of the results of various technics of non-surgical therapy of varicocele

A new method of non-surgical treatment of varicocele syndrome is described: it consists in sclerotherapy of spermatic vein by trans-femoral percutaneous catheterization with balloon-catheters. In 8 cases venous thrombosis has been induced by direct electric clotting. The techniques and a 6 months follow-up are discussed. It is pointed out that this procedure should be considered as the method of choice for tubular lesions and sub-fertility prophylaxis in young people and in childhood.     

延迟性脾破裂误漏诊原因分析

目的探讨延迟性脾破裂误漏诊原因和预防措施.方法回顾性分析总结12例延迟性脾破裂中的诊断和误漏诊的经验与教训.结果本组延迟性脾破裂的误漏诊5例(41.66%).对多发伤与脾破裂并存可能认识不足,外伤史轻微或伤员隐瞒外伤史,缺乏腹痛-缓解-突然再腹痛的典型病史,缺乏“对冲性脾破裂”力学分析和整体化诊断思路等为其误漏诊的主要原因.结论详细的外伤史和全面系统检查,重视腹以外多发伤掩盖腹内脏器伤及延迟性脾破裂可能.确立外伤-腹内脏器伤-脾破裂整体化诊断思路.不间断地辅以B超检查脾形态学变化和腹内有无积液,腹腔穿刺确定有无血腹、X线胸腹部检查观察左侧胸肋角和膈肌运动情况、必要时CT检查以尽早发现脾包膜下血肿,降低延迟性脾破裂误漏诊率.