Thrombotic risk associated with the use of iodinated contrast media in interventional cardiology: pathophysiology and clinical aspects

A review of the current knowledge of the anti-thrombotic properties of iodinated contrast media (CM) has been conducted. CM are classified according to their chemical structure, either ionic or non-ionic (monomeric or dimeric). Numerous in vitro and in vivo data show that, although all CM have anti-coagulant properties, ionic molecules are more potent than non-ionic and, furthermore, do not activate resting platelets, unlike non-ionic agents. These properties may lead to a decrease in thrombus formation during interventional procedures. Several clinical trials have shown that CM may play a role in the occurrence of acute thrombotic complications but also in delayed ischaemic events during interventional procedures. A recent meta-analysis showed that, compared to non-ionic monomers, ionic low-osmolar CM reduce the rate of coronary artery abrupt closure, but no significant difference was found with respect to ischaemic complications. Ionic CM lead to a lower deposit of thrombotic materials on catheters and guide-wires. To date, clinical data comparing ionic CM and non-ionic dimers are scarce, significantly heterogeneous and, unlike experimental data, they do not show differences between both classes of CM. Further studies are required to better understand the precise mechanisms of such interactions and to analyse the effect of CM when new antiplatelet agents or new procedures (stenting) are used, to comply with new clinical strategies.     

胰腺CT血管造影检查中造影剂浓度对增强效果的影响

目的:应用2种不同浓度的非离子型碘造影剂进行CT血管造影(CTA),定量比较两者对腹主动脉、门静脉、正常胰腺或病变周围正常胰腺在动脉期、门静脉期的增强功效及局灶性病变与病变周围正常胰腺间的增强差异。方法:使用GELightSpeed16排多层螺旋CT(MSCT),对60例临床怀疑胰腺病变的患者行腹部CTA检查,30例应用典迈伦400(每1mL含400mg碘),30例应用典比乐300(每1mL含300mg碘),其中2例应用典迈伦400的患者因造影剂外溢被排除。增强CTA检查时,经肘静脉应用高压注射器注射90mL典迈伦400或120mL典比乐300,注射造影剂后用20mL生理盐水冲洗,注射速率为3.0mL/s。结果:典迈伦400组腹主动脉CT值为(350.54±78.31)HU、门静脉的CT值为(193.00±29.10)HU;典比乐300组腹主动脉及门静脉CT值分别为(251.50±34.78)HU、(152.30±20.30)HU,2组间比较差异有统计学意义(P≤0.001;P≤0.001)。典迈伦400组正常胰腺和病变周围正常胰腺在动脉期和门静脉期的CT值分别为(84.05±22.20)HU、(111.51±21.44)HU,典比乐300组分别为(74.24±15.05)HU、(93.10±13.27)HU,2组间比较差异有统计学意义(P≤0.001;P≤0.001)。典迈伦400组病变周围正常胰腺与局灶性病变在动脉期和门静脉期增强差异的CT值分别为(132.70±112.79)HU、(165.65±119.35)HU;典比乐300组分别为(106.12±62.06)HU、(132.00±58.51)HU,2组间比较差异无统计学意义(P均>0.05)。结论:典迈伦400在显示血管及胰腺的增强功效上有明显优势。     

自制脂质微泡造影剂显影效果的研究

目的:以白蛋白微泡作对照,比较自制脂质微泡的心脏显影效果。方法:以胆固醇、卵磷脂为原料声振制备脂质微泡。以东冠注射液和全氟显作比较,评价自制脂质微泡左室及心肌的显影效果。经股静脉弹丸注射不同剂量的3种造影剂,剂量设置为:极高(0.225ml/kg)、高(0.15ml/kg)、中(0.1ml/kg)、低(0.05ml/kg)、极低(0.025ml/kg),全氟显只设极低剂量组。比较造影前后左室腔显影等级、显影时间、左室内膜边界增强节段数及心肌显影情况。结果:脂质微泡在极低剂量组和低剂量组右室显影好,但左室显影较淡;中等剂量组的显影效果与全氟显极低剂量组及东冠注射液极高剂量组相似,但显影时间仍较全氟显短。脂质微泡心肌显影只在极高剂量组较明显。结论:以胆固醇、卵磷脂为主要成分的脂质壳含气微球能实现左室及心肌显影,有望开发出新一代的心肌声学造影剂。自制脂质微泡显影效果优于东冠注射液,但逊色于全氟显。     

免疫脂质体微泡造影剂的制备及体外靶向研究

目的制备抗人肝细胞癌免疫脂质体微泡造影剂,并探讨其体外靶向作用.方法采用静电吸附法将抗人肝细胞癌单克隆抗体HAb18结合到本试验室研制的脂膜氟烷微泡造影剂表面,制备免疫脂质体微泡造影剂;采用玻片凝集实验、荧光免疫染色实验证明抗体与脂质体微泡的结合;通过花环形成及花环形成阻断实验研究免疫脂质体微泡的靶向作用.结果静电吸附法可使单抗HAb18牢固地结合到脂质体微泡上;免疫脂质体微泡围绕靶细胞形成花环,花环形成率达90%以上.结论采用静电吸附法制备的免疫脂质体微泡造影剂在体外能与人肝癌细胞高效特异结合.     

超声微泡造影剂在疾病诊断与治疗中的研究进展

超声微泡造影剂在疾病诊断与治疗中的作用日渐明显.超声微泡造影剂可用于对心脏、肝脏、肿瘤等的声学造影诊断,具有靶向性的超声微泡造影剂对组织、血栓及肿瘤的靶向显影应用前景广阔.目前的研究表明,超声微泡造影剂在治疗中也显示出巨大潜力,可作为一种有效的基因或药物运载工具.而低功率超声辐射微泡治疗肿瘤研究亦有望取得突破性进展.     

心肌超声造影在心脏占位性病变诊断中的价值

心脏占位性病变是一类发病率较低,严重威胁患者生命的疾病,其临床表现缺乏特异性,治疗和预后更因性质而异,因此早期发现及诊断心脏占位性病变对患者非常重要。心肌超声造影是近年来兴起的新技术,该技术能定性及定量评估心脏占位性病变的血流灌注,为诊断及鉴别心脏占位性病变提供依据。本文就心肌超声造影在心脏占位性病变诊断中的价值进行综述。     

超声微泡造影剂制备中乳化剂的选择

采用乳液聚合法对微泡超声造影剂的制备进行研究,重点对反应中所必需的乳化剂进行选择,并在此基础上讨论了乳化剂的用量及配比等对实验结果的影响.由本方法所制得的微泡粒径以2～8 μm的居多,浓度在9.51×109 /ml左右,单体转化率达到71%,有利于更进一步的研究.     

MR相位对比电影法在正常颈部及颅内大血管血流测量中的应用

目的运用MR相位对比电影法非侵袭性测量颈部及颅内主要血管血流流速和流量改变情况.方法测量15例正常志愿者双侧颈内动脉、椎动脉、大脑中动脉、大脑前动脉、大脑后动脉、颈静脉的血流速率并计算相应血管血流量.结果 15例正常志愿者平均总入颅血流量为(627±110) ml/min,平均颈静脉回流量为(724±115) ml/min,左右颈内动脉平均流量分别为(236±53) ml/min、(272±62) ml/min.左右椎动脉平均流量分别为(63±37) ml/min、(56±38) ml/min.左右颈静脉平均流量分别为(213±56) ml/min、(512±81) ml/min .颅内主要血管左右大脑中动脉M1段平均流量分别为(180±32) ml/min、(106±20) ml/min.左右大脑前动脉A1段平均流量分别为(174±39) ml/min、(114±26) ml/min.左右大脑后动脉平均流量分别为(63±14) ml/min、(57±13) ml/min.结论 MR相位对比电影法可较准确地反映颈部及颅内主要血管血流速率及流量改变情况.     

容积对比成像研究进展及其在胎儿小脑蚓部研究中的应用

容积对比成像(VCI)是一种新型成像技术,可增强二维图像对比度、减少噪声,使二维图像质量明显提高。本文对国内外关于胎儿小脑蚓部超声显像及测量的研究现状、VCI技术监测胎儿小脑蚓部的应用情况及研究进展、该技术的优越性和局限性进行综述。     

常规超声与超声造影诊断颈动脉粥样硬化斑块的对比研究

目的对比研究超声造影与常规超声对于颈动脉粥样硬化斑块的诊断,分析两种检查方式的利弊。方法回顾性分析我院收治的经常规超声证实存在颈动脉斑块的54例缺血性脑血管病患者的颈动脉常规超声及超声造影资料。 结果其中7例患者常规超声显示存在低回声斑块而经超声造影证实斑块分级仅为Ⅰ级;5例患者常规超声显示存在高回声斑块而经超声造影证实斑块分级为Ⅲ~Ⅳ级;3例患者经超声造影显示出常规超声未能清晰发现的颈内动脉外侧壁斑块;2例患者经过常规超声和超声造影综合分析证实存在动脉斑块致颈动脉狭窄,狭窄率估测为50%~69%。结论超声造影在诊断颈动脉粥样硬化斑块,尤其是在发现颈动脉外侧壁斑块、观察斑块内新生血管及评估斑块稳定性方面优于常规超声;在评估血管狭窄程度方面,常规超声结合超声造影综合应用要优于单纯应用常规超声。     

诊断超声介导自制微泡造影剂的溶栓效应及参数优化体外实验研究

目的 研究诊断超声介导自制微泡造影剂对血栓的溶解效应以及对影响溶栓效果的超声频率、机械指数、照射时间、微泡浓度四个参数进行探讨,确定最佳的溶栓参数组合.方法 利用统计学L9(34)正交表确定不同的超声频率(1.8 MHz、5 MHz、11 MHz)、不同机械指数(0.5、1.2、1.6)、不同照射时间(10 min、30 min、60 min)、不同微泡浓度(3.5×109/ml、4.2×109/ml、5.0×109/ml)各参数不同水平间的组合,按照正交表所示组合参数条件进行体外溶栓,计算各组间的溶栓率P=[(W0- W1)/ W0]×100%,所得数据进行极差分析,切片HE染色及电镜下观察溶栓后的血凝块结构.结果 作用时间对其溶栓率的影响最大,其溶栓的最佳条件组合为超声频率A=1.8 MHz、机械指数B=1.6、作用时间C=60 min、微泡浓度D=5.0×109/ml.HE切片染色及扫描电镜1000倍观察溶栓后血凝块内部结构松散,并伴有大量纤维素断裂,出现较大的空洞与裂隙.结论 诊断超声介导下的超声微泡造影剂具有助溶作用,并在低频率、高机械指数、延长作用时间、高微泡浓度的参数条件下溶栓效果最佳.     

Gray scale contrast enhancement and quantification in different positions of rabbit liver.

OBJECTIVE: The purpose of this study was to evaluate the difference between central and ventral peripheral positions and the difference between left and right lobes in rabbit liver with gray scale contrast enhancement. METHODS: An in vivo model of perfusion was studied with a sulfur hexafluoride contrast agent and low-mechanical-index, real-time, gray scale harmonic imaging. The contrast agent (0.1 mL/kg body weight) was applied respectively in 10 rabbits by intravenous bolus injection. The time-intensity curve was used to obtain flow-related parameters such as time to enhancement (ET), time to peak intensity (PIT), peak signal intensity (PSI), enhancement duration (ED), and area under the curve (AUC). RESULTS: There was a significant difference in parameters of the time-intensity curve between central and peripheral ventral positions of liver parenchyma (P < .05), except for the ED in the left liver. The ET and PIT were earlier, the PSI higher, the ED longer, and the AUC larger in the central position of parenchyma than in the peripheral position. In addition, the ET and PIT were earlier, the PSI higher, the ED longer, and the AUC larger in the right lobe of liver parenchyma than in the left lobe. There was a significant difference in parameters of the time-intensity curve between the left and right lobes of liver parenchyma (P < .05), except for the ET of the peripheral position. CONCLUSIONS: Flow parameters are different between central and ventral peripheral positions and between left and right lobes of hepatic parenchyma.     

临床护理路径对CT增强扫描造影剂渗漏及满意度的影响

目的探讨临床护理路径在减少CT增强扫描造影剂渗漏及提高满意度中的作用。方法选取行CT增强扫描的患者200例随机分为实验组(采用临床护理路径的特殊护理)和对照组(采用一般护理),各100例。比较2组CT增强扫描中造影剂渗漏、护理错误、来自注射误差的扫描失败、扫描时间、患者与CT技师满意程度等。结果 2组造影剂渗漏情况及护理错误情况比较,差异无统计学意义(P0.05);实验组误差扫描失败、扫描时间、患者满意度及技师满意度情况较优于对照组(P0.05)。结论临床护理路径在减少造影剂渗漏上应用效果不明显,但在提高满意度上效果显著。     

相差显微镜下红细胞形态在鉴别血尿来源中的临床价值

目的探讨相差显微镜下血尿中红细胞形态改变在鉴别血尿来源中的临床价值。方法收集肾小球性疾病血尿215例;非肾小球性血尿233例;正常对照组210例,用相差显微镜观察尿红细胞形态与临床肾活检诊断血尿进行比较,评价相差显微镜下尿红细胞形态判定血尿来源的可靠性。结果215例肾小球性血尿患者中非均一红细胞血尿阳性率为96.3%,均一性红细胞血尿阳性率为3.7%,233例非肾小球性血尿患者中均一红细胞血尿阳性率为96.1%,非均一性红细胞血尿阳性率为3.9%。相差显微镜法的灵敏度为96.3%,特异度为96.1%。结论在相差显微镜下检测红细胞形态操作简便,结果与临床符合率较高,敏感性和特异性都较高,对鉴别血尿来源和定位诊断具有一定的临床应用价值。     

Concentration and excretion of contrast agents during oral cholecystography as measured by computed tomography in dogs

Nine healthy mongrel dogs were given 2 consecutive doses of 1 of 3 cholecystographic contrast agents (iopanoic acid, sodium ipodate, and sodium tyropanoate), followed by daily computed tomograms (CT) and abdominal radiographs in a randomized crossover study in order to determine: (a) the maximum time for excretion of the contrast material from the gallbladder, (b) the maximum time for elimination of contrast material from the blood, and (c) the correlation between the density of the gallbladder on CT and the actual concentration of iodine in the gallbladder bile. In all 9 animals gallbladder opacification disappeared on CT within 4 days after administration of the contrast material. Plain abdominal radiographs did not show gallbladder opacification after 2 1/2 days. Daily blood iodine measurements showed that all of the contrast material was cleared from the blood within 7 days after administration. In 7 dogs CT imaging of the gallbladder was followed by percutaneous aspiration of bile from the gallbladder using CT guidance. There was a direct linear correlation between the actual concentration of iodine in the bile and the density of the gallbladder on CT (r=0.925). This suggests that CT measurements can be used to determine the concentration of contrast agents in the gallbladder during oral cholecystography.     

The inclusion of positive aspects of caring in the Caregiver Strain Index: Tests of feasibility and validity

Background and objective

Positive aspects of caring are commonly cited by carers and can potentially mediate carer strain. However, in outcome assessment for carers, it is still common practice to focus on the negative aspects of caring. This study explored the feasibility and validity of including positive items in a commonly used outcome measure—the Caregiver Strain Index (CSI).

Methods

Five positive items were inserted into the CSI. The resulting ‘CSI+’ questionnaire was included in a postal survey of carers in the Netherlands. Feasibility was assessed through completion rates for the CSI+ and individual items. Validity was assessed through tests of the association of the positive items and the CSI+ scores with relevant characteristics of the care (construct validity) and related scales (convergent validity). Factor analysis was carried out the CSI+ scale.

Results

The addition of the positive items did not noticeably affect the feasibility of the CSI, but did appear to improve the convergent validity of the measure. The multivariable analysis and factor analysis suggests that positive aspects of care could be grouped into ‘coping’ factors and ‘attitudinal’ factors.

Conclusion

These findings support the use of positive items in outcome assessment for carers and provide some support for the use of the CSI+ as an instrument for doing this.     

经口服超声造影剂联合彩色多普勒超声在胃疾病诊断中的应用价值

目的 探讨经口服超声造影剂联合彩色多普勒超声在胃疾病诊断中的应用价值.方法 对132例胃疾病患者口服＂胃窗声学造影剂＂后进行彩色多普勒超声仪检测,以80例健康人作为对照,检测其胃壁超声声像及胃壁厚度.并将病例组超声检测结果与病理诊断、胃镜诊断结果进行比较分析.结果 超声结果显示病例组较正常组胃壁有不同程度的增厚,超声诊断出胃溃疡、胃癌、食道贲门癌、胃腺瘤、胃平滑肌瘤、胃间质瘤和胃淋巴瘤患者共129例,诊断符合率达97.73%,与胃镜诊断结果相比,无显著差异（P〉0.05）.结论 经口服超声造影剂联合彩色多普勒超声诊断胃部疾病灵活简便,无痛苦无创伤,值得临床推广应用.     

Older husbands as caregivers of their wives: a descriptive study of the context and relational aspects of care

The purpose of this study was to describe the context and relational aspects that characterize male caregiving. The sample comprised 323 older husbands caring for their wives in Quebec (Canada). Nearly 60% of them spent at least 84 h/week caregiving and about 40% regularly performed personal care and instrumental tasks. Family provided emotional support above all and service utilization was limited for certain services. Husbands perceived relational deprivation but also personal gain relative to their role. Conflicts seldom occurred with family members. Comparisons between husbands of wives with and without memory problems revealed selected differences on context and relational variables. This study contributes to knowledge on male caregivers and provides directions for nursing practice and research.