血管内支架模型及离体血管经腔内超声三维重建的实验研究

我们自制了16个不同形状和大小的金属支架模型，置入人造血管腔中，并采用高体正常血管8条（犬腹主动脉4条，人冠状动脉4条）进行经血管腔内超声显像（IVUS）的体元模型三维重建（3DR）研究。结果显示，该技术能真实地再现支架在管腔内的形态、支架与管壁之间的间隙及离体正常血管的管腔及管壁形态，经提取后重建的支架模型与实物非常相似。经3DR测得的支架及血管腔内径与实测值均高度相关（r分别为0.96和0.99，p＜0．001）。支架与管壁之间空隙的3DR测值与实测值也高度相关（r=0.97，p＜r.0.01）。     

Assessment of abdominal lymph nodes in a normal paediatric population: An ultrasound study

During a 9 month period, 50 consecutive children were evaluated by ultrasound to determine the size, location (mesenteric vs para-aortic), number, shape and texture of abdominal lymph nodes in a normal paediatric population. High resolution linear array transducers were used with graded compression. Nodes ranging from 10 to 20 mm were recorded in the majority of subjects. In all cases mesenteric lymph nodes were larger and more numerous than para-aortic nodes. Para-aortic lymph nodes were not seen in isolation.     

A study of blood supply of liver tumors using duplex Doppler ultrasound and color Doppler flow imaging

Summary With the use of duplex Doppler ultrasound and color Doppler flow imaging(CDFI), the characteristics of blood supply in neoplasma were studied in 51 cases of 60 liver tumors, and compared with the results of surgery, pathological examination and hepatic anerial angiography. The result showed that: 1. Doppler blood flow signals could be detected in all hepatic carcinomas, and in 10 cases of 18 hemangiomas, significant difference was observed (P<0.001); 2. Doppler blood flow spectra showed pulsatile pattern in 41 of 42 hepatic carcinomas, and in 6 of 10 hemangiomas (P<0.01); and 3. the peak flow velocity was obviously lower in hemangioma group than in hepatic carcinoma group (20.34±23.93 vs 64.74±30.18 cm,P<0.001). The characteristics of CDFI show that hemangiomas and hepatocellular carcinomas are different. It can, therefore, be concluded that the blood supply of hepatic carcinomas mainly comes from hepatic arterial system, and is of value in duplex Doppler ultrasound and CDFI.     

高频超声检测颈动脉内膜-中层厚度及外周血管内皮功能评价动脉粥样硬化

目的 探讨高频超声检测颈动脉内膜-中层厚度与肱动脉内皮依赖性舒张功能在动脉粥样硬化中的诊断价值.方法 冠状动脉造影的老年患者69例及青年志愿者20例,分别行颈动脉超声检查,同时采用充气加压法测定肱动脉血流介导的内径扩张值,超声测值与冠脉造影结果对照分析.结果 ①颈动脉内膜-中层厚度值随粥样硬化斑块的增多、冠脉狭窄程度的加重而增高;②动脉粥样硬化患者在内膜-中层厚度值增高之前即可出现内皮功能损伤,肱动脉内径扩张值降低早于内膜-中层厚度值增高之前出现,内径扩张值随冠脉狭窄程度加重而下降.结论 高频超声检测颈动脉内膜-中层厚度、内径扩张值诊断早期动脉粥样硬化敏感性高,并且有助于对冠脉狭窄程度作出判断.     

全主动脉弓替换术中顺行性脑灌注时血流变化观察

目的　利用前瞻性随机对照方法比较全主动脉弓替换术中单侧顺行性脑灌注 (ASCP)和双侧ASCP时视网膜中央动脉、球后血管血流变化和血S1 0 0蛋白浓度变化。方法　 1 6例全主动脉弓替换术患者随机分为单侧AS CP和双侧ASCP组 ,每组各 8例。两组均行术前术后颅脑计算机体层摄影 (CT)。术中采用经眼球超声监测视网膜中央动脉及球后血管血流。术中术后动态测定血S1 0 0蛋白浓度。结果　两组各有 1例出现短暂性神经功能异常。ASCP过程中单侧组右侧视网膜中央动脉可探及血流 ,左侧视网膜中央动脉不可探及 ,双侧组两侧视网膜中央动脉均可探及血流。所有患者球后动脉均可探及血流。两组间各阶段血S1 0 0蛋白浓度无显著性差异 (P >0 .0 5 )。结论　在基底动脉环完整 ,存在有效侧支循环条件下 ,单侧灌注操作较为简便 ,双侧灌注在ASCP期间两侧脑灌注较为均衡 ,但两种灌注方法对S1 0 0蛋白浓度的影响无显著性差异。     

Prospective randomised study of urgent haemorrhoidectomy compared with non-operative treatment in the management of prolapsed thrombosed internal haemorrhoids

OBJECTIVE: To compare the outcome of urgent haemorrhoidectomy with conservative treatment for prolapsed thrombosed internal haemorrhoids. METHODS: A prospective randomised study of 50 patients with prolapsed thrombosed internal haemorrhoids was carried out using clinical and ultrasonic outcome measures. Peri-operative bed occupancy and the presence of symptoms at 6 and 24 months were compared. Endoanal ultrasonic scanning was carried out to investigate anal sphincter integrity in those patients willing to be studied. RESULTS: The median length of hospital stay for the group treated conservatively; 2 nights (range 1-9 nights) was significantly shorter than for the group treated by urgent haemorrhoidectomy; 4 nights (range 1-12 nights, P < 0.01). There was no difference between treatment groups in the number of patients with symptoms at six or 24 months. Urgent haemorrhoidectomy was associated with a significantly higher incidence of endosonographically detected anal sphincter damage in 18 patients: 66%vs 0% (P = 0.009). CONCLUSION: Conservative treatment for prolapsed thrombosed internal haemorrhoids is associated with shorter in patient stay and less anal sphincter damage compared with operative treatment.     

Relationship Among MRTA, DXA, and QUS

Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS.     

压力导丝在冠状动脉内支架置入中的意义

目的　通过与血管内超声 ( IVUS)相比较 ,探讨压力导丝在评价冠脉内支架置入即刻效果 ,指导优化支架置入中的作用。方法　 5 1例患者置入冠脉内支架后先后予血管内超声和压力导丝检测判断是否达到相应的理想支架置入标准。若未达标准 ,则进一步采用更高压力同样球囊或更大球囊再扩张。结果　支架置入后 IVUS判断 3 1例达到标准 ,不需再扩张 ,15例不满意者再扩张支架 ,支架内截面积增加 2 4 .3 % ( P<0 .0 5 ) ,最终 4 1例 ( 89% )得到满意 IVUS,5例因超声导管未跨过支架无超声资料 ;压力导丝检测 3 5例达到标准 ,不需再扩张 ,16例不满意者再扩张支架最终 4 5例 ( 88% )得到满意结果 (心肌部分血流储备 ,FFRmyo>0 .90 )。血管内超声和压力导丝两者在判定理想支架置入方面有很好的相关性 ,符合率达 90 %。以血管内超声检测作金标准 ,应用受试者工作特性曲线 ( ROC)计算心肌部分血流储备 FFRmyo预测理想支架置入的最佳临界点为 0 .90。结论　压力导丝是指导冠脉支架置入更方便、安全的有效手段 ,有广泛推广应用的价值     

Die dopplersonographische Bestimmung der maximalen Blutströmungsgeschwindigkeit in der Diagnostik peripherer arterieller Verschlußkrankheiten bei Diabetes mellitus

Summary Seventy-five diabetic and 40 nondiabetic subjects who where suffering from peripheral vascular disease were studied in order to determine whether the degree of the severity of their disease can be better calculated by Doppler ultrasound examinations of the peak velocity than by the systolic pressure of the peripheral bloodstream. In 46 examinations of normal controls the mean value of the peak velocity was 13.3±3.3 cm/s with a standard deviation of 15.4%±13.2% on one day and 16.1%±15.9% on different days. Considering patients with or without diabetes mellitus the velocity was significantly decreased in correlation to an increasing degree of severity of the vascular disease (P<0.001); however, the decrease was lower in diabetic than in nondiabetic subjects (6.9±2.8 vs 4.6±6.2,P<0.05). The systolic pressure hardly decreased, but remained higher in all stages of peripheral vascular disease of diabetics than in the nondiabetic subject (P<0.05 toP<0.005). There was a significant decrease of the systolic pressure only in diabetic subjects with the most advanced degree of the disease, i.e. stage IV (P<0.05).It is concluded from this study that Doppler ultrasound measurements of the peak velocity of the peripheral bloodstream are a useful parameter to calculate the degree of severity of the peripheral vascular disease. In addition, it is concluded than peak velocity is an even better prognostic indicator of peripheral vascular disease than is measurement of the systolic blood pressure at the feet.

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Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation     

Homocysteine-Lowering Therapy and Early Progression of Transplant Vasculopathy: A Prospective, Randomized, IVUS-Based Study

Although observational studies suggest that hyperhomocysteinemia may be a risk factor for coronary allograft vasculopathy (CAV), prospective data on homocysteine-lowering interventions and CAV development are lacking. We, therefore, randomized 44 de novo heart transplant (HT) recipients to 15 mg/day of 5-methyl-tetrahydrofolate (n=22), or standard therapy (control group, n=22) to investigate the effect of homocysteine lowering on the change in coronary intimal hyperplasia during the first 12 months after transplant, as detected by intra-vascular ultrasound (IVUS). Although 12 months after HT, homocysteinemia was lower in folate-treated patients (p<0.001), coronary intimal area increased similarly in the two groups (p>0.4). Conversely, hypercholesterolemia and cytomegalovirus infection were both associated with increased intimal hyperplasia (p<0.04), independently from folate intake. Sub-group analysis revealed that folate therapy reduced intimal hyperplasia in patients with hyperhomocysteinemia before randomization (n=19; p=0.02), but increased intimal hyperplasia in patients with normal homocysteine plasma concentrations (p=0.02). This bimodal effect of folate therapy persisted significantly after adjusting for cytomegalovirus infection and hypercholesterolemia. Despite effective in prevent hyperhomocysteinemia after heart transplantation, folate therapy does not seem to affect early CAV onset. However, sub-group analysis suggests that folate therapy may delay CAV development only in patients with baseline hyperhomocysteinemia, while may favor CAV progression in recipients with normal baseline homocysteinemia.