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1.
彩色多普勒超声诊断乳腺肿瘤   总被引:16,自引:3,他引:13       下载免费PDF全文
目的分析乳腺良恶性肿瘤的二维及彩色多普勒超声表现,评价彩色多普勒超声在诊断乳腺癌中的应用价值。方法对674例乳腺肿瘤患者(恶性327例,良性347例)进行二维超声及彩色多普勒超声检查,以二维超声观察肿块的大小、形态、边界、内部回声等,以彩色多普勒超声观察肿块内部血流信号,测量血流峰值速度(PSV)和阻力指数(RI)等。结果674例中超声发现肿块671例,肿块大小0.50cm×0.41cm~5.42cm×4.10cm。恶性肿瘤肿块纵横径比≥1.0占69.11%(226/327),肿块边界不整齐,呈“锯齿”状或“蟹足”状约占81.35%(266/327),肿块内部沙粒样钙化点占61.47%(201/327);彩色多普勒对血流信号的显示率为92.97%(304/327),PSV为15.34~39.76cm/s,RI为0.65~0.98,RI≥0.70占91.61%(262/286)。良、恶性肿瘤在肿块纵横径比、肿块边界、沙粒样钙化及血流信号、PSV、RI等方面差异均有统计学意义(P〈0.01)。结论二维超声结合血流信号、PSV及RI值可显著提高乳腺良、恶性肿瘤的诊断与鉴别,彩色多普勒超声在乳腺癌的诊断中具有重要作用。  相似文献
2.
Laparoscopic insufflation of the abdomen reduces portal venous flow   总被引:12,自引:12,他引:19  
Background: The adverse effects of sustained elevated intraperitoneal pressure (IPP) on cardiovascular, pulmonary and renal systems have been well documented by several reported experimental and clinical studies. Alteration in the splanchnic circulation has also been reported in animal experiments, but details of the exact hemodynamic changes in the flow to solid intraabdominal organs brought on by a raised intraperitoneal pressure in the human are not available. The aim of the present study was to estimate effect of increased IPP on the portal venous flow, using duplex Doppler ultrasonography in patients undergoing laparoscopic cholecystectomy. Methods: The studies were performed using the SSD 2000 Multiview Ultrasound Scanner and the UST 5536 7.0-MHz laparoscopic transducer probe. Details of the measurements were standardized in according to preset protocol. Statistical evaluation of the data was conducted by the two-way analysis of variance (ANOVA). Results: The flow measurement data have demonstrated a significant (p < 0.001) decrease in the portal flow with increase in the intraperitoneal pressure. The mean portal flow fell from 990 ± 100 ml/min to 568 ± 81 ml/min (−37%) at an IPP of 7.0 mmHg and to 440 ± 56 mmHg (−53%) when the IPP reached 14 mmHg. Conclusions: The increased intraperitoneal pressure necessary to perform laparoscopic operations reduces substantially the portal venous flow. The extent of the volume flow reduction is related to the level of intraperitoneal pressure. This reduction of flow may depress the hepatic reticular endothelial function (possibly enhancing tumor cell spread). In contrast, the reduced portal flow may enhance cryo-ablative effect during laparoscopic cryosurgery for metastatic liver disease by diminishing the heat sink effect. These findings suggest the need for a selective policy, low pressure or gas-less techniques to positive-pressure interventions, during laparoscopic surgery in accordance with the disease and the therapeutic intent. Received: 19 March 1996/Accepted: 4 July 1997  相似文献
3.
高频彩色多普勒血流显像诊断乳腺恶性肿瘤   总被引:12,自引:4,他引:8       下载免费PDF全文
目的探讨高频彩色多普勒血流显像(CDFI)在乳腺恶性肿瘤诊断的临床应用。方法回顾60例在我院手术治疗的乳腺恶性肿瘤的CDFI高频超声声像图特征,并与手术、术后病理结果对照。结果乳腺恶性肿瘤在形态、边缘、包膜、内部回声、后方回声、纵横比具有特异性,乳腺恶性肿瘤内及周边血流信号丰富,肿瘤内部出现粗大彩色血流信号。结论高频彩色多普勒超声是一种对乳腺恶性肿瘤的诊断具有重要的临床应用价值的无创伤性检查方法。  相似文献
4.
超声产前诊断胎儿畸形   总被引:12,自引:0,他引:12       下载免费PDF全文
目的探讨超声在产前诊断胎儿畸形的临床价值。方法采用彩色多普勒超声诊断仪对2230例孕11~40周的孕妇进行系统超声检查并随访。结果2230例孕妇中,超声诊断胎儿畸形28例,漏诊8例。发生畸形位居前三的是心血管畸形,神经管畸形。泌尿系统畸形。漏诊病例多为心血管畸形及较小畸形。结论超声检查可以对胎儿形态结卞句方面的明显畸形作出明确的产前诊断,明显减少出生缺陷,提高人口素质。对于心血管畸形及较小畸形还有待于改进方法,加强规范操作。  相似文献
5.
彩超和血流检查诊断下肢深静脉血栓的对比研究   总被引:11,自引:0,他引:11  
目的 评估彩色多普勒超声(以下简称:彩超)及多普勒超声血流检查(以下简称:血流检查)在下肢深静脉血栓方面的诊断价值.方法 对84例患者(包括下肢深静脉血栓形成、深静脉血栓后遗症及原发性下肢静脉瓣膜功能不全的患者)共92侧下肢分别进行深静脉的彩超及血流检查,并与下肢深静脉造影(做为"金标准")做比较.结果 与下肢深静脉造影对比,彩超的准确率、敏感性、特异性、漏诊率、误诊率、约登指数、比数积、阳性预测值、阴性预测值及Kappa值分别为96.7%、95.7%、97.8%、4.3%、2.2%、0.935、990.0、97.8%、95.7%及0.935(P:0.037).由于彩超的Kappa值(0.935)>0.75,且P(0.037)<0.05,故理论上彩超可以替代下肢深静脉造影检查;血流检查的以上指标分别为89.1%、87.2%、91.1%、12.8%、8.9%、0.783、70.0、91.1%、87.2%及0.783(P=0.065).结论 彩超可以作为确诊下肢深静脉血栓首选的更可靠的无创伤检查方法.  相似文献
6.
Impact of intraoperative ultrasonography in laparoscopic liver surgery   总被引:11,自引:3,他引:8  
Background Laparoscopic surgery has gained growing acceptance, but this does not hold for laparoscopic surgery of the liver. This mainly includes diagnostic procedures, interstitial therapies, and treatment of liver cysts. However, the authors believe there is room for a laparoscopic approach to the liver in selected cases. Methods A prospective study of laparoscopic liver resections was undertaken with patients who had preoperative diagnoses of benign lesion and hepatocellular carcinoma with compensated cirrhosis. The inclusion criteria required that hepatic involvement be limited and located in the left or peripheral right segments (segments 2–6), and that the tumor be 5 cm or smaller. The location of the tumor and its transection margin were defined by laparoscopic ultrasound (LUS). Results From December 1996, 17 (5%) of 313 liver resections were included in the study. There were 5 benign lesions and 12 hepatocellular carcinomas in cirrhotic patients. The mean age of the study patients was 59 years (range, 29–79 years). The LUS evaluation identified the presence of new hepatocellular carcinoma nodules in two patients (17%). The resections included 1 bisegmentectomy, 8 segmentectomies, 3 subsegmentectomies, and 3 nonanatomic resections. The mean operative time, including laparoscopic ultrasonography, was 156 ± 50 min (median, 150 min; range, 60–250 min), and the perioperative blood loss was 190 ± 97 ml. There was no mortality. Conversion to laparotomy was necessary for two patients. Postoperative complications were experienced by 3 of 15 patients, all of them cirrhotics. One of the patients had a wall hematoma, and the remaining two patients had bleeding from a trocar access requiring a laparoscopic reexploration. The mean hospital stay for the whole series was 6.9 ± 4.9 days (median, 6 days; range, 2–25 days) and 5.6 ±1.4 days (median, 6 days; range, 2–8 days) for the 15 laparoscopic patients. Conclusion Laparoscopic treatment should be considered for selected patients with benign and malignant lesions in the left lobe or frontal segments of the liver. Evaluation by LUS is indispensable to guarantee precise determination of the segmental tumor location and the relationship of the tumor to adjacent vascular or biliary structures, excluding adjacent or adjunctive new lesions. The evolution of laparoscopic hepatectomies probably will depend on the development of new techniques and instrumentations.  相似文献
7.
Color Doppler Imaging Predicts Portal Invasion by Pancreatic Adenocarcinoma   总被引:9,自引:0,他引:9  
Background Tumor infiltration of the intima of the portal vein (PV) and superior mesenteric vein (SMV) by pancreatic adenocarcinoma is classically considered a criterion for unsuitability for resection and poor prognosis. This study was performed to evaluate modern color duplex imaging (CDI) for the assessment of PV/SMV infiltration by pancreatic adenocarcinomas. Method From 1994 to 2005, Whipple’s procedure or pylorus-preserving pancreato-duodenectomy (PPPD) was performed in 303 patients with pancreatic adenocarcinoma; 35 of these underwent partial PV/SMV resection. Applying a previously reported CDI score, we evaluated the integrity of the echogenic border layer between the vein and tumor (mural demarcation) and maximum blood flow velocity (V max) in the PV segment in contact with the tumor. The results were compared to the final histological findings in the resected venous walls. Results CDI findings correlated well with the histological invasion grades. By measuring V max and evaluating mural demarcation, we observed a sensitivity of 66.7% and 100% and a specificity of 98.3% and 93.9%, respectively, in predicting full thickness vein invasion, including the intima. V max above 80 cm/s and lack of mural demarcation were predictors of PV/SMV invasion. The postoperative survival rates depended on the depth of tumor infiltration into the PV/SMV. Conclusions Modern CDI is a reliable and valid technique for evaluation of morphological and hemodynamic parameters in the portal vein segment adjacent to pancreatic adenocarcinoma. Maximal blood-flow velocity in the portal segment in contact with the tumor and absence of the echogenic vessel-parenchymal sonographic interface are parameters predictive of tumor infiltration of the portal intima.  相似文献
8.
复杂肾结石经皮肾镜取石术后结石残留的原因与处理   总被引:9,自引:0,他引:9  
目的:探讨复杂肾结石PCNL术后结石残留的原因及处理方法.方法:回顾分析我院行二期PCNL取石的35例复杂肾结石患者的临床资料,既往有开放手术史17例,2例因术中出血影响视野改二期手术,合并肾盏憩室内结石2例.结果:除2例需辅助ESWL治疗外,其余33例在B超和输尿管镜辅助下,行二期PCNL全部成功取净残留结石.其中3例因残留结石所在肾盏位置远离经皮肾通道或在与皮肾通道平行的肾盏内,重新建立另一通道取石;1例行3通道取石.结论:术中出血、肾盏憩室内结石、既往开放手术史和肾内集合系统解剖异常,是PCNL术后结石残留的主要原因;术中B超及软镜的应用,可以清楚显示有无残留结石及其所在肾盏的位置;了解结石与经皮肾通道的位置关系,帮助引导最大限度地清除结石.  相似文献
9.
超声造影检测和诊断小肝癌的价值   总被引:8,自引:4,他引:4  
目的探讨实时超声造影检测和诊断体积较小原发性肝癌的价值。方法分析353例共378个经临床和病理检查证实的直径≤3cm的原发性肝癌的超声造影表现,包括造影的增强时相和增强方式,并与病理类型相比较。结果所有原发性肝癌中96.6%(365/378)的病灶动脉相显示增强,其中317(83.9%)个病灶增强早于肝实质,48(12.7%)个病灶增强与肝实质同步;增强方式中329(87.0%)个病灶呈整体增强,35(9.3%)个呈斑片状增强,14(3.7%)个病灶呈环状增强。在门脉相和晚期相,342(90.5%)个病灶相对于肝实质呈低回声。若将造影时病灶动脉相增强早于或同步于肝实质以及门脉期消退作为超声造影诊断肝癌的标准,则敏感性为87.3%(330/378);若将整体增强和斑片状增强作为原发性肝癌的特异增强方式,结合增强方式和时相,则超声造影鉴别诊断原发性肝癌的敏感性为92.9%(351/378)。结论超声造影可实时动态观察肝肿瘤相对于肝实质的灌注和廓清过程,揭示肿瘤的血流动力学,在鉴别诊断小肝癌中具有重要的临床实用价值。  相似文献
10.
Background. Altered cerebral circulation, as reported duringnormal pregnancy, and in patients with pre-eclampsia, can beassociated with changes in cerebral vascular reactivity and/orcerebral autoregulation. The aim of our study was to performa comparative assessment of cerebral haemodynamics, includingvascular reactivity and autoregulation, in pre-eclamptic patients,healthy pregnant women, and healthy non-pregnant women. Methods. Thirty patients with pre-eclampsia were recruited.Age- and height-matched healthy pregnant (n=30) and non-pregnantcontrol (n=30) groups were also recruited. Monitoring includedtranscranial Doppler ultrasonography, end-tidal carbon dioxideand non-invasive arterial pressure measurement. Cerebral autoregulationwas assessed by performing the transient hyperaemic response(THR) test. The cerebrovascular reactivity to carbon dioxide(CRCO2) was assessed by measuring middle cerebral artery bloodflow velocity (MCAFV) after induced changes in end-tidal carbondioxide. Estimated cerebral perfusion pressure (eCPP) and criticalclosing pressure (CrCP) were calculated using established formulae.Statistical analysis included ANOVA with Tukey’s pairwisecomparisons. Results. Mean arterial pressure (MAP) was increased in pre-eclampsia(P<0.05). Mean MCAFV was lower in healthy pregnancy (P<0.05),but in pre-eclampsia it was similar to the non- pregnant group.When compared with the non-pregnant group, mean eCPP was higherin the healthy pregnant and pre-eclamptic groups (P<0.05).There were no meaningful differences in cerebral autoregulationor CRCO2. Conclusions. Healthy pregnancy increases eCPP, presumably bydecreasing CrCP. In pre-eclampsia, eCPP is maintained at thesame level as in healthy pregnancy despite an increased MAP.Pre-eclampsia has no significant effect on cerebral autoregulationor CRCO2. Br J Anaesth 2002; 89: 687–92  相似文献
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