Assessment of hemodynamic changes in human kidney grafts induced by cyclosporin infusion

Abstract. Cyclosporin A (CyA) nephrotoxicity is at least partly caused by the vasoconstrictive action of the drug. In this study we set out to assess this hemodynamic effect of CyA on Doppler spectra obtained in arteries of human renal allografts. Doppler spectra of renal arteries were obtained shortly before and after the start of CyA infusion in renal transplant recipients. Doppler spectrum analysis revealed a significant change in several spectrum-derived parameters. T_max (acceleration time of the systolic frequency peak), in particular, showed a decrease after 4 h of CyA administration (106 ± 58 ms vs 76 ± 36 ms in segmental arteries; P <0.05). On day 2 the T_max returned to its original value (117 ± 57 ms). Thus, Doppler spectrum analysis enables one to detect temporary hemodynamic changes in the transplanted kidney following CyA administration. These observations may be useful in differentiating causes of renal dysfunction by Doppler spectrum analysis in clinical transplantation.     

Interrater reliability of plaque morphology classification in patients with severe carotid artery stenosis

Objective - Ultrasonographic assessment of carotid artery plaque morphology is widely used to identify patients at high risk for stroke. However, the reliability of plaque analysis in high-grade stenosis is uncertain. We determined the interrater reliability of sonographic plaque morphology analysis in patients with severe carotid artery stenosis. Material and methods - Duplex Doppler was performed on 114 patients with 80–99% stenosis of the internal carotid artery using a Siemens Quantum 2000 D with a handheld 7.5 MHz transducer. B-mode pictures with and without color coding were printed on a Sony color video printer UP-5000 W. Three raters independently evaluated plaque echolucency, heterogeneity, calcification, and surface structure. Interrater agreement was calculated by a jackknife procedure generating kappa values and two-sided 95% confidence intervals. Results - Kappa values and 95% confidence intervals were 0.05 (-0.07 to 0.16) for plaque surface structure, 0.15 (0.02 to 0.28) for plaque heterogeneity, 0.18 (0.09 to 0.29) for plaque echogenicity, and 0.29 (0.19 to 0.39) for plaque calcification. The upper bounds of all of the confidence intervals were below the 0.40 level suggested for minimal reliability. Conclusion - The low interrater agreement indicated that unaided visual assessment of static B-mode pictures to assess plaque morphology in patients with severe carotid artery stenosis is not reliable. Other evaluation procedures and standardized criteria, as yet undeveloped, are needed to improve reliability.     

Hepatic arterial resistive indices: Correlation with the severity of cirrhosis

Forty-three patients who were scheduled to undergo a percutaneous liver biopsy were evaluated with Doppler sonography to determine the hepatic arterial resistive index (RI). The histologic specimens were graded by a pathologist regarding cirrhosis and inflammation. The specimens demonstrated no cirrhosis in 12 of 43 (28%) patients, early cirrhosis in 10 of 43 (23%), and established cirrhosis in 21 of 43 (49%). Analysis also revealed that inflammation was absent in three of 43 (7%) patients, minimal in seven of 43 (16%), mild in 17 of 43 (40%), moderate in 13 of 43 (30%), and severe in three of 43 (7%). Hepatic artery RIs (without correction for heart rate) ranged from 0.64+0.06 in patients with early cirrhosis to 0.68 ±0.09 in patients with severe inflammation. There was no significant correlation between the degree of cirrhosis and/or inflammation and hepatic artery RI (with or without correction for heart rate). We conclude that Doppler determination of hepatic artery RIs is not a reliable method of predicting the severity of hepatic cirrhosis and/or inflammation.     

Duplex sonographic criteria for measuring carotid stenoses

PURPOSE: The aim of this retrospective study was to determine optimal duplex sonographic criteria for use in our institution for diagnosing severe carotid stenoses and to correlate those findings with angiographic measurements obtained by the European Carotid Surgery Trial (ECST), North American Symptomatic Carotid Endarterectomy Trial (NASCET), and Common Carotid (CC) methods of grading carotid stenoses. METHODS: We analyzed the angiographic data using the ECST, NASCET, and CC methods and compared the results with the duplex sonographic findings. We then calculated the sensitivity, specificity, positive and negative predictive values, and accuracy of the duplex sonographic method. Taking these parameters into account, the optimal intrastenotic peak systolic velocity (PSV) and end diastolic velocity (EDV) were derived for diagnosing severe stenoses according to the 3 angiographic methods. RESULTS: Optimal PSV and EDV values for diagnosing a 70% or greater stenosis in our laboratory were as follows: with the NASCET method of angiographic grading of stenoses, PSV 220 cm/second or greater and EDV 80 cm/second or greater, and with the ECST and CC methods, PSV 190 cm/second or greater, and EDV 65 cm/second or greater. The optimal PSV and EDV for diagnosing a stenosis of 80% or greater with the ECST grading method were 215 cm/second or greater and 90 cm/second or greater, respectively. CONCLUSIONS: Duplex sonography is a sensitive and accurate tool for evaluating severe carotid stenoses. Optimal PSVs and EDVs vary according to the angiographic method used to grade the stenosis. They are similar for stenoses 70% or greater with the NASCET method and for stenoses 80% or greater with the ECST method.     

经颅彩色双功超声对大脑中动脉狭窄的诊断价值

目的探讨经颅彩色双功超声（TCCS）对大脑中动脉（MCA）狭窄的诊断价值。 方法对93例临床疑有脑动脉狭窄的患者进行TCCS检查，以数字减影血管造影（DSA）结果为金标准，分析TCCS诊断的准确性。 结果TCCS具有很高的诊断准确性，与DSA结果比较差异无显著性意义（P〉0．05）。TCCS诊断MCA狭窄的敏感性、特异性、阳性预测值、阴性预测值分别为91．5％、98．4％、96．4％、98．4％。 结论在诊断MCA狭窄方面，TCCS和DSA有良好的相关性，可作为MCA狭窄的初步筛选检查方法。     

55例肾血管病变彩色多普勒超声评价

以双功和彩色多普勒超声诊断５５例肾血管病变，包括肾动脉狭窄、肾小动脉硬化、肾动脉发育不良、肾动－静脉轲菜、急性肾静脉血栓和肾静脉曲张。与其中３８例完整肾血管造影资料结果对照，超声诊断符合率９５％。认为多种肾血客病变的肾内血流多普勒均具特征性改变，综合其互有差异的多普勒定量指标（ＳＶ、Ｒｌ，Ａｃ），典型的多普勒频谱形态（锯齿形、雪橇形）和征象各的彩色血流图像（花簇状、流线样、闪烁样），能够对多种肾血     

Radiographic contribution to diagnosis and treatment of complications from peritoneoscopy

Peritoneoscopy is a valuable nonsurgical procedure for evaluating patients with malignant disease. Directed biopsies of suspected tumor masses may be obtained, and peritoneoscopy can frequently obviate the need for laparotomy. Although the complication rate is low, the radiologist must be aware of potential problems. Radiologists may participate not only in the diagnosis and localization of these complications but also in their therapy by interventional techniques. The radiographic findings in four patients with complications of peritoneoscopy are presented.     

彩色多普勒超声检测自体肾和移植肾的肾动脉狭窄

目的 探讨彩色多普勒超声在检测自体肾和移植肾肾动脉狭窄(RAS)中的价值和局限性。方法 回顾性对照分析了临床可疑RAS的30例自体肾和14例移植肾的彩色多普勒超声(US)与磁共振动脉造影(MRA)及动脉血管造影的结果。并将狭窄肾动脉扩张／再通术前后的肾动脉血流速度，肾内小动脉多普勒波形特征(升速时间-AT，升速指数-AI，阻力指数-RI)进行了比较。结果 30例自体肾RAS的超声诊断中有2例假阳性和2例假阴性。14例移植肾RAS阳性的超声检查无误差。肾动脉血流速度和肾内小动脉的多普勒波形在RAS纠正术前后有显著改变。结论 尽管彩色多普勒超声在检测RAS中有局限性，其仍被列为对可疑RAS病例的初步影像检查，并在观测随访RAS纠正术后的肾血流灌注及狭窄复发中有重要作用。综合分析肾动脉及肾内动脉的血流速度和多普勒波形特征并参考有关临床资料有助于提高超声诊断RAS的准确性。     

Effect of Doppler angle in diagnosis of internal carotid artery stenosis.

OBJECTIVE: The purpose of this study was to compare velocity measurements obtained with 2 fixed insonation angles and to investigate whether there is a difference in their ability in determining internal carotid artery (ICA) stenosis. METHODS: Eighty-seven patients with ICA stenosis were examined with color duplex ultrasonography. Velocity measurements were made at 60 degrees and 45 degrees insonation angles, and they were compared with Bland-Altman and receiver operating characteristic curve analysis. RESULTS: Peak systolic velocity (PSV) and end-diastolic velocity measurements obtained at the 60 degrees insonation angle were higher compared with those obtained at the 45 degrees insonation angle (24.2% and 24.7%, respectively). The ICA-to-common carotid artery PSV ratio, conversely, was slightly higher (3.9%). Although the threshold values for the same velocity parameters obtained at 2 different insonation angles were different, the accuracy ratios (sensitivity and specificity) were not. With application of the Society of Radiologists in Ultrasound consensus criteria to the data obtained at either of the 2 insonation angles, the accuracy ratios of PSV and end-diastolic velocity were found to be statistically different. In the ICA-to-common carotid artery PSV ratio, however, there were no statistically significant differences in the accuracy ratios. CONCLUSIONS: Doppler velocity measurements made at different fixed insonation angles show considerable differences. In determining ICA stenosis, although optimal thresholds are different, the diagnostic performance is not different. In determining ICA stenosis with color duplex ultrasonography, angle-specific thresholds must be determined, and examinations must be made at a fixed angle.