彩色多普勒超声对卵巢肿瘤的诊断价值

目的 探讨卵巢良恶性肿瘤的彩色多普勒超声血流形态学和血流动力学特征。方法 对95例患者105个卵巢病变，用能量多普勒观察肿物内的血流形态学改变(包括血管的分级，血管是否有畸形)，用脉冲多普勒检测肿瘤内的血流动力学。观测指标：收缩期峰值流速(VPS)、舒张末期流速(VεD)、平均流速(VM)、搏动指数(PI)、阻力指数(RI)及是否存在舒张期切迹。用逐步回归的方法对上述指标进行分析。结果 所观测的血流形态学及动力学各指标在良恶性卵巢肿瘤之间的差异均存在显著性意义。逐步回归显示，RI的意义最大。RI界值定为0．51时，其鉴别良恶性卵巢肿瘤的敏感性和特异性分别为98．0％，96．2％。结论 RI是鉴别卵巢肿瘤良恶性质的最有意义的血流动力学指标。     

Strong impact of estrogen environment on Doppler variables used for differentiation between benign and malignant breast lesions.

OBJECTIVES: To analyze the impact of an estrogen environment on the Doppler variables usually used for differentiation between benign and malignant lesions. METHODS: A total of 142 malignant and 107 benign breast lesions was demonstrated (in 91 premenopausal and 152 postmenopausal patients) by B-mode ultrasound. Intratumoral vessels were visualized by color Doppler and blood flow velocity waveforms were analyzed by pulsed Doppler. The number of intratumoral vessels and the Doppler variables, peak systolic velocity, resistance and pulsatility indices and the peak systolic/diastolic ratio were evaluated in different endocrine milieus represented by menopausal status, phase of the menstrual cycle, intake of oral contraceptives or hormone replacement therapy. RESULTS: In malignant tumors the Doppler variables resistance and pulsatility indices and the systolic/diastolic ratio were significantly higher in postmenopausal women than in premenopausal women. In benign tumors significantly higher values of resistance and pulsatility indices were also detected in post- compared to premenopausal women (P < or = 0.05). In premenopausal patients with benign tumors taking oral contraceptives the number of intratumoral vessels was significantly higher, while resistance index and systolic/diastolic ratio values were decreased compared to patients with spontaneous menstrual cycles. In postmenopausal patients hormone replacement therapy did not influence Doppler variables in the benign or the malignant groups. CONCLUSION: Our results demonstrate a robust influence of menopausal status and oral contraceptives on Doppler variables of breast lesions. We believe it is likely that some of the differences in the Doppler variables found in reports comparing benign and malignant breast lesions were caused by their association with a pre- or postmenopausal status.     

颅内动脉狭窄经皮血管内支架成型术前后血流动力学改变与脑血管造影的对照研究

目的:通过经颅彩色多普勒对颅内动脉狭窄患者经皮血管内支架成型术前后血流动力学改变与脑血管造影的对照,评价经颅彩色多普勒在颅内动脉狭窄经皮血管内支架成型术中的价值。方法:58例颅内动脉狭窄的患者经皮血管内支架成型术治疗后,其病变血管的血流动力学多项指标(Vm,Vs,Vd,PI,RI)与治疗前进行比较。结果:51例患者与术前比Vs,Vm,Vd下降,PI值增高,RI值变化不大,经颅彩色多普勒及脑血管造影随访所有患者无再发狭窄;5例患者出现Vs,Vm,Vd增快,PI值增高,但均未见反流信号;2例出现Vs增快,Vm增快,Vd降低。中、重度狭窄经颅彩色多普勒与脑血管造影相符率较高,分别占89%,83%。结论:经颅彩色多普勒与脑血管造影均可作为经皮血管内支架成型术术前术后血流动力学改变的评价手段。     

Three-dimensional power Doppler vascular sampling: a new method for predicting ovarian cancer in vascularized complex adnexal masses.

OBJECTIVE: The purpose of this study was to explore the role of a new concept ("vascular sampling") as a third step to discriminate benign and malignant lesions in B-mode and color Doppler sonographically suggestive adnexal masses. METHODS: Forty-five women (mean age, 52.3 years; range, 17-82 years) with the diagnosis of complex adnexal masses on B-mode sonography were evaluated using 3-dimensional power Doppler sonography. Four women had bilateral masses. After a morphologic reevaluation was done, color pulsed Doppler sonography was used to obtain flow velocity waveforms, and velocimetric indices were calculated (resistive index, pulsatility index, and peak systolic velocity). Thereafter, 3-dimensional power Doppler sonography was used to assess vascularization of highly suggestive areas (gross papillary projections, solid areas, and thick septations), meaning a focused assessment ("sampling") of a suggestive area of the tumor. With a virtual organ computer-aided analysis program, vascular indices (vascularization index, flow index, and vascular flow index) were automatically calculated. A definitive histologic diagnosis was obtained in each case. RESULTS: Forty masses (82%) were malignant and 9 (18%) were benign. Morphologic evaluation revealed 10 (20%) unilocular solid masses, 20 (41%) multilocular solid masses, and 19 (39%) mostly solid masses. Blood flow was found in all cases. Median vascularization index (15.5% versus 8.2%; P = .002), flow index (33.6 versus 20.8; P = .007), and vascular flow index (5.2 versus 2.3; P = .001) were significantly higher in malignant tumors. No differences were found in resistive index (0.43 versus 0.45; P = .770), pulsatility index (0.62 versus 0.65; P = .694), and peak systolic velocity (15.6 versus 12 cm/s; P = .162). CONCLUSIONS: Three-dimensional power Doppler vascular sampling seems to be a promising tool for predicting ovarian cancer in vascularized complex adnexal masses. It could be better than conventional color pulsed Doppler imaging.     

Gray scale and color flow Doppler characterization of uterine tumors.

The aim of this study was to investigate gray scale and color flow characteristics of a group of patients with a suspected uterine pathologic condition. One hundred and twenty-two consecutive patients at the Women's Cancer Center, University of Minnesota, undergoing transvaginal sonography and color flow Doppler imaging for suspected uterine corpus abnormality made up the study group. After gray scale morphologic assessment, color flow Doppler imaging of the tumor and uterus was performed, including the ipsilateral uterine artery. Malignant tumors were confirmed pathologically in all 35 patients who had them. In comparing patients with benign versus malignant tumors, gray scale morphologic assessment confirmed that malignant uterine tumors (31 endometrial cancers and four sarcomas) were more likely to have a thickened echoic endometrium (P = < 0.0001), be enlarged (P = 0.004), to be retroverted (P = 0.02), and to lack a subendometrial halo (P < 0.0001). Patients with four benign and 13 malignant tumors demonstrated increased flow when assessed by CFD. The calculated sensitivity of increased color flow in predicting malignancy was 39%, with a specificity of 92%, a positive predictive value of 77%, and a negative predictive value of 71%. No difference existed between the benign and malignant groups for the systolic, diastolic, and mean velocities and for the calculated pulsatility index and resistive index in both sampled uterine and intramyometrial or tumor vessels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Doppler ultrasonographic evaluation of blood flow in the superior mesenteric artery in celiac patients and in healthy controls in fasting conditions and after saccharose ingestion

We studied, by means of Doppler ultrasonography, the blood flow in the superior mesenteric artery in 12 untreated patients with celiac disease (nontropical sprue) and in 15 healthy controls; peak systolic velocity, end diastolic velocity, mean velocity, flow volume, and resistive index were measured in the fasting state and at regular intervals after ingestion of 0.5 liter of water containing 50 g of saccharose. Under fasting conditions, celiac patients showed peak systolic velocity, end diastolic velocity, mean velocity, and flow volume values significantly higher than those of normal subjects, whereas resistive index was significantly lower. After saccharose ingestion these parameters showed greater variations in normal subjects than in celiac patients. Fasting end diastolic velocity turned out to be the best parameter to distinguish celiac patients from healthy subjects. Doppler ultrasonography of the superior mesenteric artery could discriminate between normal subjects and celiac patients with overt disease. However, these data need further confirmation given the limited sample that we studied; moreover, the capability of this technique in distinguishing nontropical sprue from other gastrointestinal diseases that cause increasing splanchnic flow remains to be ascertained.     

Evaluation of ocular arterial changes in glaucoma with color Doppler ultrasonography.

The purpose of this study was to evaluate hemodynamic changes of the retrobulbar vasculature caused by different intraocular pressures with color Doppler ultrasonography. Fifty normal eyes in 25 patients, 13 patients with normal tension glaucoma, and 19 patients with acute glaucoma and increased intraocular pressure (greater than 30 mm Hg) were enrolled in this study. In 15 of 19 patients with acute glaucoma patients, follow-up color Doppler ultrasonography was also undertaken after laser peripheral iridectomy when the intraocular pressure had returned to normal. The peak systolic velocity, end diastolic velocity, resistive index, time average maximum velocity, and pulsatility index were compared in different vessels, including the central retinal artery, lateral posterior ciliary artery, medial posterior ciliary artery, and ophthalmic artery in each orbit. The peak systolic velocity, end diastolic velocity, and time average maximum velocity of the central retinal artery were significantly lower (P<0.01) in acute glaucoma patients than in the control group. The resistive index and pulsatility index of the central retinal artery were significantly higher (P<0.01) in acute glaucoma patients than in the control group. The end diastolic velocity of the lateral and medial posterior ciliary arteries was significantly lower in patients with acute glaucoma than in the control group, and the resistive index and pulsatility index of both of these arteries were significantly higher (P<0.001) in patients with acute glaucoma than in the control group. However, no statistical significantly differences were found in the peak systolic velocity or time average maximum velocity in either of the posterior ciliary arteries; similarly, no statistically significant differences were noted in any of the parameters in the ophthalmic artery between the control group and the group with acute glaucoma. The pulsatility index of the central retinal artery and of the lateral and medial posterior ciliary arteries was significantly lower (P<0.01) in acute glaucoma patients after laser therapy than in acute glaucoma patients before laser therapy. The resistive index of both posterior ciliary arteries was also significantly lower (P<0.004) in acute glaucoma patients after laser therapy than before laser therapy. All parameters for all vessels examined among the normal subjects, the patients with normal tension glaucoma, and the patients with acute glaucoma after laser therapy when the intraocular pressure had returned to normal showed no statistically significant differences. Color Doppler ultrasonography is a good modality for both imaging and studying the hemodynamics of the perioptic nerve vessels.     

Doppler velocimetry of the fetal middle cerebral and renal arteries: interobserver reliability.

Using color and pulsed Doppler ultrasonography, the interobserver reliability of measurements in the fetal circulation was evaluated in 41 pregnancies of 25 to 39 weeks' gestation. Two observers recorded flow velocity waveforms from the middle cerebral and renal arteries for measurement of peak systolic, minimum diastolic, and mean velocities, pulsatility index, and resistive index. Intraclass correlation coefficient of reliability was calculated by analysis of variance. Substantial interobserver agreement was found for pulsatility index and minimum diastolic velocity in both arteries. Therefore, these measurements have the greatest clinical applicability.     

Transvaginal gray scale and color Doppler sonography in primary ovarian cancer and metastatic tumors to the ovary.

OBJECTIVE: To compare gray scale and color Doppler features of primary and metastatic ovarian carcinomas. METHODS: Clinical, sonographic (gray scale and color Doppler), and histopathologic data of 143 patients with primary (n = 127 adnexal masses) and metastatic (n = 34 adnexal masses) ovarian cancer were reviewed. Morphologic gray scale parameters assessed were bilaterality, tumor volume, echogenicity, and presence of septa, papillary projections, or solid areas. Color Doppler parameters were presence of blood flow, tumor blood flow location (central versus peripheral), subjective impression of blood flow amount (scanty, moderate, or abundant), lowest resistive index, lowest pulsatility index, and maximal peak systolic velocity (centimeters per second). RESULTS: No statistical differences were found in bilaterality, tumor volume, presence of septa, papillary projections or solid areas, presence of blood flow, tumor blood flow location, subjective impression of blood flow amount, lowest resistive index, lowest pulsatility index, and maximal peak systolic velocity. Metastatic carcinomas were more frequently purely solid tumors (47% versus 26%; P = .001; likelihood ratio, 2.4; 95% confidence interval, 1.2-4.7). CONCLUSIONS: The presence of a purely solid tumor indicates a higher probability of metastatic carcinoma than primary ovarian cancer. However, with the use of gray scale and color Doppler sonography, it is difficult to differentiate primary ovarian carcinomas from metastatic tumors to the ovary.     

彩色多普勒超声在骨肿瘤诊断中的应用价值

目的：探讨彩色多普勒超声在诊断骨肿瘤中的价值。方法：应用二维及彩色多普勒超声显像对22例恶性和27例良性骨肿瘤进行检查，观察分析病变的声像图特征、血流分布和血流动力学变化。结果：良、恶性组问血流分级有显著差异（P＜0．01），组间收缩期峰值流速（PSV）及舒张末期流速（EDV）的差异不明显（P〉0．05），阻力指数（RI）差异显著（P＜0．01）。Pearson线性相关分析显示骨肿瘤的声像图特征和血流情况与良、恶性均有良好的相关性。结论：超声对骨肿瘤病变周围软组织浸润的判断具有独特的优势，CDFI对良、恶性的鉴别诊断有一定的意义。     

Prediction of brain blood flow using pulsed Doppler ultrasonography in newborn lambs

The purpose of this study was to evaluate the ability of pulsed Doppler ultrasonography to predict brain blood flow by comparing measurements made in basal cerebral arteries using a pulsed Doppler system with measurements of brain blood flow using radioactive microspheres in lambs. We measured the instantaneous maximum velocity during peak systole and end diastole and the mean velocity over the pulse cycle in basal cerebral arteries, calculated Pourcelot's index of resistance and Gosling's pulsatility index, and used regression analysis to compare the pulsed Doppler measurements with brain blood flow measured with radioactive microspheres. Pulsed Doppler measurements of the peak systolic, end diastolic, and mean flow velocity in basal cerebral arteries were directly related to brain blood flow. In contrast, no linear relationship was detected between the resistance or pulsatility indices and brain blood flow measured by microspheres (p greater than 0.14). Prediction of brain blood flow for individual subjects lacks the quantitative precision necessary for use as a clinical tool. However, the direct relationship between brain blood flow and the peak systolic, end diastolic, and mean flow velocities in basal cerebral arteries supports the use of these measurements in clinical research for the qualitative assessment of change in brain blood flow.     

血流速度测定在乳腺肿瘤诊断中的应用价值

作者应用彩色多普勒超声测定了７６例乳腺肿瘤内血流收缩期峰速和阻力指数，并对其临床应用价值作了分析。结果表明恶性肿瘤ＶＰ值明显高于良性肿瘤，良恶性肿瘤ＲＩ值无显著性差异。统计学分析了显示良恶性肿瘤之间的临界流速值为１２ｃｍ／ｓｅｃ，该值对直径２ｃｍ以下乳癌诊断敏感性、特异性和准确性分别为９５．５％、１００％和９６．６％。作者认为流速测定有助于乳腺肿瘤，特别是直径２ｃｍ以下肿瘤的鉴别诊断。     

Reproducibility and repeatability of transabdominal uterine artery Doppler velocimetry between 10 and 14 weeks of gestation.

OBJECTIVE: To assess the intraobserver repeatability and interobserver reproducibility of Doppler flow velocity measurements of the uterine arteries in pregnant women between 10 and 14 weeks of gestation. METHODS: In this prospective study, Doppler velocimetric indices (maximum peak systolic velocity, end-diastolic velocity, peak systolic velocity/end-diastolic velocity ratio, pulsatility index and resistance index) were measured twice by the same trained observer in each uterine artery of 63 women. In 47 of these women, a second trained observer then repeated the measurements. In addition, both observers classified qualitatively the blood flow with regard to the presence or absence of an early diastolic notch. The coefficient of variation, intraclass correlation coefficients, within observer and between observers repeatability coefficient and Cohen's kappa coefficient were calculated. RESULTS: The best parameter in terms of repeatability and reproducibility in both uterine arteries was the resistance index with a low coefficient of variation and high intraclass correlation coefficient. The other parameters (pulsatility index, peak systolic velocity/end-diastolic velocity ratio, peak systolic velocity and end-diastolic velocity) performed poorly with high coefficients of variation on both sides. Agreement between the repeated observations (inter- and intraobserver) with regard to the presence or absence of an early diastolic notch was good. CONCLUSION: Doppler velocimetry of uterine artery blood flow is technically feasible between 10 and 14 weeks of gestation. This study demonstrates that this technique is prone to measurement errors. Quantitatively, the resistance index appears to be the most repeatable and reproducible measurement at this gestational age. Qualitative assessment of the waveform morphology also shows high levels of intra- and interobserver agreement.     

彩色多普勒超声观测妊娠妇女肾动脉血流改变

应用彩色多普勒超声诊断仪对１５６例妊娠妇女及７６例正常妇女的肾动脉血流进行了观察，探讨了妊娠对肾动脉血流动力学的影响。结果显示：①无论正常或妊娠妇女，肾动脉血流速度及外周血管阻力在左右肾无明显差异。②妊娠后血流速度较非孕妇女增加，但外周血管阻力Ｓ／Ｄ、ＰＩ、ＲＩ与非孕妇女比较无明显变化。③随孕周增加，肾动脉血流速度在２８周前有增大趋势，孕２８周达高峰并维持高水平。肾动脉外周血管阻力在各孕周间无明显差异。研究证明，彩色多普勒血流检测可以准确了解肾脏血液动力学情况，有较高临床价值。     

Validity of pulsatility and resistance indices in classification of adnexal tumors with transvaginal color Doppler ultrasound.

Transvaginal pulsed color Doppler ultrasound was used to examine 72 patients with a pelvic mass preoperatively. Tumor morphology was assessed, prominent areas of vascularization within the tumor were observed and the pulsatility index and the resistance index of tumor and uterine arteries were measured. Flow velocity waveforms with low pulsatility are considered to reflect neovascularization. The ultrasound diagnoses were compared with histopathological or cytological diagnoses. There were 61 benign, eight malignant and three borderline cases. In 75% of the malignant and 23% of the benign tumors, an intratumoral flow with a low pulsatility was detectable. The mean pulsatility index of tumor blood vessels was 1.2 in benign, 0.7 in malignant and 0.6 in borderline neoplasms. The corresponding mean resistance index values were 0.6, 0.5 and 0.5. The differences were not significant and the overlap between the malignant and benign lesions was large. The pulsatility index and resistance index of uterine arteries were significantly decreased in malignant tumors. The results show that, using a cut-off resistance index value of 0.6, the sensitivity and specificity of color Doppler in the detection of malignant and potentially malignant tumors were 82% and 72%, respectively. However, a practical cut-off level for either pulsatility or resistance indices, that could assist in differentiating between malignant or benign lesions, does not seem to exist.     

Comparison of visually evoked peak systolic and end diastolic blood flow velocity using a control system approach.

Transcranial Doppler sonography measures blood flow velocity in basal cerebral vessels with high accuracy. For quantification, time averaged mean blood flow velocities are used most because the peak systolic and end diastolic blood flow velocities mark the velocity extremes of one heart cycle. It is known, from hemodynamic measurements of the neurovascular coupling mechanism, that the end diastolic velocity is more sensitive for change in hemodynamics than the peak systolic velocity. Thus, we used a recently introduced control system approach to compare both indices for their use in functional transcranial Doppler tests focusing on hemodynamics of blood flow velocity change. We enrolled 65 healthy young volunteers without a medical history of cardiovascular risk factors, and performed a visual stimulation test. Peak systolic and end diastolic maximal blood flow velocities were used after transformation to relative data for control-system analysis. Due to Doppler artefacts, 95% of peak systolic and 86% of end diastolic data sets were analyzed. Results showed statistically significant differences for resting blood flow velocity and the control system parameter gain, attenuation and rate time, whereas the parameters' natural frequency and time delay were equal. Increase in relative blood flow velocity in the posterior cerebral artery due to visual-cortical stimulation was higher in end diastolic values than peak systolic data. Using a complex visual stimulation paradigm, the higher sensitivity of the end diastolic index is of no practical use. Being less influenced by Doppler artefacts, the peak systolic velocity index is more feasible for control-system analysis of dynamic blood flow regulation.     

Transcranial color Doppler imaging of brain arteriovenous malformations in adults

This study was performed to investigate the utility of transcranial color Doppler sonography in evaluating adult cerebral arteriovenous malformations. Twelve patients with such malformations underwent sonography. Spectral Doppler sonographic assessment included peak systolic velocity, end diastolic velocity, and resistive index within the intracranial and extracranial vessels. Color Doppler sonography was used to visualize the site of shunting. Paired and unpaired Student's t-tests were used to determine significance of spectral findings. The nidus was seen in eight of 10 pial malformations. The nidi in two patients were located in the parietal region and not visualized. When compared with the corresponding contralateral artery, feeding arteries (identified in all 10 of the pial lesions) demonstrated diminished resistive indices (P = 0.09). Similarly, the end diastolic velocity was increased in all feeding arteries (P = 0.03). When compared with published normal values, the peak systolic and end diastolic velocities were significantly elevated and the resistive indices were low (P < 0.0003). Transcranial color Doppler sonography depicted the nidi of pial arteriovenous malformations in 80% of cases. Feeding arteries demonstrated abnormal peak systolic velocity, end diastolic velocity, and resistive index in all cases when compared with published values. Transcranial color Doppler sonography is not a good screening tool due to limited acoustical window, but it may be useful for noninvasive study of the physiology of arteriovenous malformations as they are treated.     

The influence of angiotensin II-induced vasoconstriction on common carotid artery blood flow and velocity-time profiles in normal women.

Non-invasive methods of measuring blood velocity, especially Doppler velocimetry, are being increasingly used in obstetrics to provide observational information. We report a preliminary study of their usefulness in experimental studies. Doppler velocimetry was used to assess blood flow and velocity-time profiles in the common carotid artery of seven women of reproductive age before and during the incremental administration of angiotensin II. Angiotensin II infusion evoked the expected increments in systolic and diastolic arterial pressure and fall in heart rate. Angiotensin II was associated with a dose-dependent fall in maximum blood velocity, which, at an average rise in systolic blood pressure of 23 mmHg, had fallen from 91 +/- 16 to 52 +/- 4 (mean +/- SD, p < 0.01). Absolute maximum blood velocity was strongly correlated with systolic and diastolic blood pressures (p < 0.001 for both). The minimum velocity was unaltered throughout, and the calculated flow did not change significantly (490 +/- 100 cf. 380 +/- 50 ml/min). Overall, these findings are in agreement with those previously reported using invasive methods of monitoring flow during angiotensin II infusion, and further support the usefulness of Doppler velocimetry as an investigative tool in human physiology and pharmacology.However, the pulsatility index, resistance index and systolic/diastolic velocity ratio all fell significantly during angiotensin II infusion (p < 0.01 for all). The conventional interpretation of a fall in these indices, i.e. reduced downstream resistance, is clearly erroneous under these circumstances, since angiotensin II induces arteriolar vasoconstriction. This illustrates the importance of interpretation of Doppler velocity envelopes in the light of pharmacological mechanisms likely to be evoked by the experimental procedure.     

Intraobserver and interobserver variability of transabdominal Doppler velocimetry measurements of the fetal ductus venosus between 10 and 14 weeks of gestation.

OBJECTIVE: To assess the intraobserver repeatability and interobserver reproducibility of transabdominal Doppler ultrasound measurements of ductus venosus blood flow in fetuses between 10 and 14 weeks of gestation. DESIGN: A prospective study with the following end-points: coefficient of variation, intraclass correlation coefficients within and between observers, repeatability coefficient and Cohen's kappa coefficient. SUBJECTS AND METHODS: Doppler velocimetry indices (maximum peak systolic velocity during ventricular systole, end-diastolic velocity during atrial contraction, peak systolic velocity/end-diastolic velocity ratio and pulsatility index for veins) were successfully measured three times by the same trained observer in 67 fetuses. Of these, in 24 fetuses, the measurements were then repeated by a second trained observer. In addition, both observers classified qualitatively the blood flow as being normal or abnormal with regard to the presence or absence/reversal of flow during atrial contraction. RESULTS: The intraobserver repeatability of the pulsatility index for veins measurements was considered good with a coefficient of variation of 8.9% and an intraclass correlation coefficient value of 0.62. However, inconsistencies occurred in maximum peak systolic velocity, end-diastolic velocity and systolic/diastolic ratio measurements, which had coefficients of variation of 19%, 28.5%, and 25.4%, respectively. The corresponding intraclass correlation coefficient values were 0.70, 0.69 and 0.60. Interobserver reproducibility of these indices was unsatisfactory, the coefficient of variation varying between 11.5% and 47.2% and the intraclass correlation coefficient between 0.18 and 0.44. Agreement between the repeated observations with regard to interpretation of normal or abnormal blood flow varied from moderate (interobserver) to very good (intraobserver). CONCLUSIONS: There was considerable variability in all Doppler indices except for the intraobserver repeatability of the pulsatility index for veins measurement. This makes the implementation of the semiquantitative Doppler indices in a screening setting difficult. On the contrary, qualitative classification of the flow velocity waveforms seemed to be a reproducible method.     

Variability of Doppler parameters in the healthy kidney: an anatomic-physiologic correlation.

Contradictory results have been obtained in classifying various renal diseases when trying to use the resistive index measured by duplex Doppler technique in renoparenchymal arteries. These measurements may have been influenced by the lack of standardization of the anatomic site at which the renoparenchymal artery is sampled. To elucidate this influence, we measured the resistive index, peak systolic velocity, end diastolic velocity, and pulsatility index in 120 healthy kidneys at three different positions of the renal vasculature. The resistive index at the level of the interlobar-arcuate arteries proved to be the parameter with the most consistent results and should be preferred in clinical applications.