Three-dimensional quantification of tumor vascularity as a tertiary test after B-mode and power Doppler evaluation for detection of ovarian cancer.

OBJECTIVE: The purpose of this study was to investigate the role of 3-dimensional (3D) quantification of tumor vascularity in the differential diagnosis of pelvic indeterminate masses with a solid appearance or unilocular or multilocular cysts with a solid component showing central vascularization on 2-dimensional power Doppler sonography. METHODS: One hundred fifty-seven consecutive pelvic masses in 153 patients were included in this study and underwent sonography before surgery. Masses that showed a typical benign pattern on B-mode sonography (n = 112) and indeterminate masses with peripheral or absent flow on power Doppler sonography (n = 10) were not evaluated by 3D sonography. Only masses with central vascularization were submitted to 3D power Doppler imaging (n = 35). The following 3D vascular parameters were calculated: relative color and flow measure (similar to the vascularization flow index obtained with other systems). RESULTS: With receiver operating characteristic curve analysis, the best cutoff values for relative color and flow measure were 4.4 and 2.7, respectively. Flow measure had sensitivity of 68% and specificity of 40% in the overall population submitted to 3D power Doppler sonography. Accuracy slightly increased when masses with small papillary projections (<10 mL) were excluded. In this group (n = 22), sensitivity was 83%, and specificity was 50%. CONCLUSIONS: In masses with central vascularization on 2-dimensional power Doppler sonography, the use of 3D quantification of tumor vascularity had low diagnostic accuracy in the detection of adnexal malignancies, although an increase in accuracy in masses with a solid portion of greater than 10 mL was reported.     

Intraobserver and interobserver reproducibility of 3-dimensional power Doppler vascular indices in assessment of solid and cystic-solid adnexal masses.

OBJECTIVE: The purpose of this study was to assess the intraobserver and interobserver reproducibility of 3-dimensional (3D) power Doppler angiography-derived vascular indices in evaluation of vascularized solid and cystic-solid adnexal masses. METHODS: Stored 3D power Doppler angiographic volume data from 12 consecutive women with a diagnosis of a complex adnexal mass (6 cystic-solid and 6 solid) evaluated and treated at our institution were retrieved from our database for analysis. Two examiners performed the calculations blinded to each other. Calculations were performed offline in a computer using Virtual Organ Computer-Aided Analysis software (plane A, 9 degrees rotation step) to assess volume and vascularization (vascularization index, flow index, and vascularization-flow index) from solid areas within the tumor. In all cases, a definitive histologic diagnosis was obtained. Intraobserver and interobserver reproducibility was assessed by calculating the intraclass and interclass correlation coefficients for each index. RESULTS: All tumors proved to be malignant after surgical removal. Intraobserver reproducibility for both examiners and interobserver reproducibility were high for all indices (interclass correlation coefficient > 0.95). CONCLUSIONS: Three-dimensional power Doppler angiography is a reproducible technique for offline assessment of stored 3D volume data of vascularized adnexal masses.     

Three-dimensional power Doppler vascular network assessment of adnexal masses: intraobserver and interobserver agreement analysis.

OBJECTIVE: The purpose of this study was to assess intraobserver and interobserver agreement for tumor vascular network evaluation as assessed by 3-dimensional (3D) power Doppler sonography for discriminating benign from malignant adnexal masses. METHODS: Stored 3D power Doppler angiographic volume data from 39 women with a diagnosis of a vascularized adnexal mass who were evaluated and treated at our institution were retrieved from our database for analysis. Two different examiners (observer A, with 6 years of experience in 3D sonography; and observer B, with 1 year of experience) reviewed 3D sonograms blinded to each other. Three-dimensional vascular network reconstruction was done with surface rendering in the color mode. Malignancy was considered in the presence of at least 2 of the following: irregular branching, vessel caliber changes, microaneurysms, and vascular lakes. A definitive histologic diagnosis was obtained in all cases. Intraobserver and interobserver agreement rates were estimated by calculating the kappa index. RESULTS: Twenty (51%) tumors were malignant, and 19 (49%) were benign. Intraobserver agreement was good for observer A (kappa = 0.69) and moderate for observer B (kappa = 0.54). Interobserver agreement was moderate (kappa = 0.49). CONCLUSIONS: We found intraobserver and interobserver agreement to be moderate for 3D power Doppler assessment of the vascular network in adnexal masses.     

Intraobserver and interobserver reproducibility of ovarian volume, antral follicle count, and vascularity indices obtained with transvaginal 3-dimensional ultrasonography, power Doppler angiography, and the virtual organ computer-aided analysis imaging program.

OBJECTIVES: The purpose of this study was to assess intraobserver and interobserver reproducibility of the parameters of ovarian response and oocyte ability, studied by 3-dimensional ultrasonography and power Doppler angiography (PDA), and the possible influence of the ovarian functional stage. METHODS: Twenty-nine women were included in an in vitro fertilization program. Fourteen women were evaluated after pituitary suppression (basal group), and 15 were scanned on the human chorionic gonadotropin administration day, after gonadotropin ovarian stimulation (stimulated group). A first observer acquired 2 volumes for each ovary. Another observer performed a second analysis of the volumes acquired by the first observer. We analyzed ovarian volume, follicle number in the basal group, vascularization index, flow index, and vascularization-flow index. The volumes were processed by the Virtual Organ Computer-Aided Analysis imaging program using plane A and 15 degrees rotational steps. RESULTS: Ovarian volume showed excellent intraobserver and interobserver agreement, with an intraclass correlation coefficient (Intra-CC) and an interclass correlation coefficient (Inter-CC) close to the unit. The Intra-CC and Inter-CC about the number of follicles were 0.964 and 0.978, respectively. Vascularity indices showed an Intra-CC greater than 0.90. The vascularization index and the vascularization-flow index showed higher interobserver than intraobserver reproducibility (Inter-CC > 0.96 for both). The flow index Inter-CC was 0.898. The reproducibility differences between the basal and stimulated ovary measurements were not significant. CONCLUSIONS: There is an excellent intraobserver and interobserver reproducibility of the ovarian volume, follicle counts, and 3-dimensional PDA indices. The ovarian functional stage has no influence on the reliability. Three-dimensional ultrasonography and PDA improve the study of ovarian parameters, and their reliability impels a change in the current clinical routine of performing and interpreting ultrasonography.     

Accuracy of 3-dimensional color Doppler-derived flow volumes with increasing image depth.

OBJECTIVES: We and others have reported on the use of digital color Doppler sonography from real-time 3-dimensional (3D) echocardiography and its use in accurately calculating cardiac flow volumes, namely stroke volume (SV) and, hence, cardiac output. However, in some patients, image depth is higher than average, and this may affect the accuracy of volume calculation. We sought to investigate the impact of image depth and the accompanying change in signal strength, spatial resolution, and pulse repetition frequency on the accuracy of SV calculation from 3D color Doppler data in an in vitro model. METHODS: A tube model of the left ventricular outflow tract was constructed from plastic tubing and connected to a pulsatile pump. The volume flowing through the tube was imaged using a 3D echocardiography system. Stroke volumes from the pump were computed from the DICOM data using commercially available software and compared with a reference standard of timed volumes with the use of a graduated measuring cylinder over a range of depth settings and SVs. RESULTS: There was good correlation between the 3D-derived SVs and the reference cylinder measures over all depths from 4 to 16 cm at 1-cm increments with a tube diameter of 17 mm, a pump rate of 60 beats/min, and SVs ranging from 20 to 70 mL. The average r(2) value for the 13 different depths was 0.976. However, the accuracy of the 3D method of volume calculation appeared to fall at depths greater than 13 cm, especially at higher SVs. CONCLUSIONS: Stroke volume calculation from real-time 3D color Doppler data in this in vitro study shows that at depths greater than approximately 13 cm, accuracy decreases, especially at higher SVs. This may be due to decreased resolution and the reduced frame rate at these depths. At shallower depths, volume calculation form the 3D Doppler data appears very accurate.     

Power M‐Mode Transcranial Doppler Examination of the Ophthalmic Artery in Pregnancy

Our aim was to describe the standard operating procedure for transcranial Doppler investigation of the ophthalmic artery in pregnancy, determine the interobserver and intraobserver variability using power M‐mode technology, and review the existing literature. Accordingly, 27 healthy pregnant or immediately postpartum women were enrolled and underwent transcranial Doppler investigation of the ophthalmic artery using power M‐mode technology. Good interobserver and intraobserver variability was observed for both, especially with respect to the clinically important indices. Transcranial Doppler power M‐mode examination of the ophthalmic artery is easy and reproducible and holds a great deal of potential for investigation in pregnancy.     

Reproducibility of endometrial vascular patterns in endometrial disease as assessed by transvaginal power Doppler sonography in women with postmenopausal bleeding.

OBJECTIVE: The purpose of this study was to assess the intraobserver and interobserver agreement for identifying different endometrial vascular patterns using power Doppler sonography in women with postmenopausal bleeding and a thickened endometrium. METHODS: Digitally stored sonographic images from a random sample of 65 patients with postmenopausal bleeding and a thick endometrium (>5 mm) on B-mode sonography and evaluated by transvaginal power Doppler sonography for assessment of endometrial blood flow mapping were evaluated by 5 different examiners with different levels of expertise in Doppler sonography. Intraobserver and interobserver agreement according to the level of experience were assessed by calculating the kappa index. RESULTS: Intraobserver agreement was good or very good for all experienced examiners (kappa = 0.78-0.96) and moderate (kappa = 0.52) for the inexperienced examiner. Interobserver agreement was moderate among all experienced examiners (kappa = 0.45-0.80). The inexperienced examiner showed fair or moderate interobserver agreement (kappa = 0.32-0.45). CONCLUSIONS: Our results indicate that endometrial blood flow mapping using transvaginal power Doppler sonography is acceptably reproducible. More experience was associated with better intraobserver and interobserver agreement.     

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.     

Intraobserver and interobserver variability of ovarian volume, gray-scale and color flow indices obtained using transvaginal three-dimensional power Doppler ultrasonography.

OBJECTIVE: To assess intraobserver and interobserver variability in ovarian volume and gray-scale and color flow index measurements using transvaginal, three-dimensional, power Doppler ultrasonography. METHODS: Eleven women (22 ovaries) were examined on day 8 of controlled ovarian hyperstimulation therapy, which was part of their in vitro fertilization treatment protocol. The patients were examined twice by the first observer and once by the second observer. The acquired volume datasets were analyzed using the VOCAL imaging program, enabling the assessment of ovarian volume, vascularization index (VI), flow index (FI), vascularization flow index (VFI) and mean grayness (MG). For these parameters the intraclass (intra-CC) and interclass (inter-CC) correlation coefficients, within-observer and between-observers repeatability coefficient (r) and limits of agreement were calculated. RESULTS: Both intraobserver and interobserver repeatability of ovarian volume measurements were considered very good with an intra-CC value of 1.00 and inter-CC value of 0.99, respectively. Also VI, FI, VFI and MG measurements were repeatable by a single observer, the intra-CC ranging from 0.82 to 0.91. The interobserver reproducibility was also good for VI, VFI and MG measurements (inter-CC values 0.73, 0.70 and 0.81, respectively), but for FI measurements the reproducibility was poor (inter-CC = 0.29, r = 7.87). CONCLUSIONS: In general, the intraobserver reproducibility was better than interobserver reproducibility for all parameters. The volume assessments were reproducible both by one observer and by two separate observers. The intraobserver and interobserver variabilities were acceptable for VI, VFI and MG, whereas for FI the interobserver reproducibility was poor. Our results suggest that measurement of gray-scale and color Doppler flow indices is reproducible thus allowing them to be used in clinical practice and research.     

Role of Spectral Doppler Sonography in the Evaluation of Partial Testicular Torsion

Objective. The purpose of this series was to evaluate the role of spectral Doppler and color flow Doppler sonography in the evaluation of partial testicular torsion. Methods. Eight cases of partial testicular torsion, diagnosed on the basis of abnormal spectral Doppler waveforms or abnormal color flow Doppler findings, were retrospectively pooled from 2 teaching hospitals. Results. The age group ranged from 4 to 85 years. Testicles with partial testicular torsion showed variable spectral Doppler patterns, including increased, similar, or decreased amplitude of the arterial waveform relative to the contralateral testicle. Two cases showed reversal of arterial diastolic flow, and 1 case showed diastolic flow variability within the same testicle. Decreased blood flow was observed on color flow Doppler sonography in 7 of the 8 patients. Conclusions. Variability of the Doppler waveform when compared with the contralateral testicle and reversal of diastolic blood flow are indirect clues that aid in the diagnosis of partial testicular torsion.     

Interobserver Reproducibility of Transabdominal 3‐Dimensional Sonography of the Fetal Brain

Objective. The purpose of this study was to assess the interobserver reproducibility of transabdominal 3‐dimensional (3D) fetal neurosonography. Methods. This was a prospective observational study. We studied 23 consecutive singleton pregnancies between 18 and 23 weeks' gestation. All cases had normal fetal neurosonographic examination findings, which were confirmed after birth. A 3D sonographic volume of the fetal head was acquired transabdominally by a single operator using an axial approach. Fetal brain anatomy was later analyzed offline by 2 different operators. Axial, sagittal, and coronal views of the fetal brain were obtained to perform a detailed evaluation of the fetal brain. Each operator defined the scanning planes obtained as adequate or inadequate. Results were evaluated with 2 × 2 tables and the Cohen κ coefficient to assess interobserver agreement. Results. Good‐quality multiplanar images were obtained in 23 of 23 cases. The rate of adequate visualization was 100% for all of the axial planes, with κ values of 1.00. For sagittal and coronal planes, the rate of visualization ranged between 78% and 91%, with κ values ranging between 0.61 and 0.83. Conclusions. Transabdominal 3D sonography of the fetal brain at 18 to 23 weeks' gestation has an acceptable degree of interobserver reproducibility.     

Three‐Dimensional Sonographic Characteristics of Deep Endometriosis

Objective. The purpose of this presentation is to investigate the potential role of 3‐dimensional (3D) sonography in the assessment of deep endometriosis. Methods. Cases of deep endometriosis are presented to illustrate the spectrum of appearances obtained with 3D sonography. In addition, we evaluate the possible role of other functions included in 3D equipment, such as the niche mode and tomographic ultrasound imaging (TUI). Results. Three‐dimensional image rendering could allow a good analysis of the endometriotic nodule; in fact, in all presented cases, this reconstruction seems to clearly show the irregular shapes and borders of the lesions. This technique allows unrestricted access to an infinite number of viewing planes, which can be very useful for correctly locating lesions within the pelvis and evaluating the relationship with other organs. The stored 3D volumes can be reassessed and compared by the same or different examiners over time. This characteristic may be relevant for monitoring the effect of medical therapies over time. In the niche mode, sonographic imaging is represented as a “cut‐open” view of the internal aspect of the nodule and its surrounding tissue. This additional function, which is associated with TUI, could be particularly useful for evaluation of the extension of a nodule in the rectovaginal septum, the depth of infiltration, and the relationship with the rectosigmoid junction or ureter. Conclusions. In the near future, 3D sonography in deep infiltrating endometriosis could be an interesting mode of research with positive effects in everyday clinical practice.     

Clinical usefulness of 3-dimensional sonography and power Doppler angiography for diagnosis of endometrial carcinoma.

OBJECTIVE: The purpose of this study was to assess whether endometrial volume (EV) and 3-dimensional (3D) power Doppler indices can discriminate between hyperplasia and endometrial carcinoma and can predict extension of the endometrial carcinoma. METHODS: Eighty-four women with uterine bleeding and a histopathologic diagnosis of endometrial hyperplasia (n = 29) or carcinoma (n = 55) were preoperatively examined by transvaginal 3D sonography and power Doppler angiography. Endometrial thickness (ET), EV, the vascularization index (VI), the flow index (FI), the vascularization-flow index (VFI), and the intratumoral resistive index (RI) were measured. A histopathologic diagnosis was made after endometrial biopsy was performed by hysteroscopy or curettage. RESULTS: The EV and 3D power Doppler indices (VI, FI, and VFI) were significantly higher in endometrial carcinoma than endometrial hyperplasia, whereas the intratumoral RI was significantly lower (P < .05). A VFI of 2.07 was the best cutoff for predicting endometrial carcinoma, with sensitivity of 76.5% and specificity of 80.8%. No significant differences were noticed for ET. The endometrial VI was significantly higher when the tumor stage was greater than I. All the 3D power Doppler indices were significantly higher when the carcinoma infiltrated more than 50% of the myometrium. The intratumoral RI was significantly lower in cases with a high histologic grade, myometrial infiltration of more than 50%, and lymph node metastases. CONCLUSIONS: The VI, 3D power Doppler indices, and the intratumoral RI are more useful than ET for differentiating between hyperplasia and endometrial carcinoma. Intratumoral blood flow evaluated by pulsed Doppler sonography and 3D power Doppler angiography can predict the spread of endometrial carcinoma.     

Comparison of 3‐ and 2‐Dimensional Sonographic Techniques for Counting Ovarian Follicles

Objective. The purpose of this study was to compare 3‐dimensional (3D) and 2‐dimensional (2D) ovarian follicle counts and 3D counts using stored volumes between experienced and inexperienced operators. Methods. Follicles larger than 5 mm were counted on 1 randomly selected ovary. Two‐dimensional follicle counts were compared with stored 3D volumes by the same experienced operator (registered diagnostic medical sonographer [RDMS]). Counts using 3D stored data were compared between the experienced operator and inexperienced operator (principal investigator [PI]). The mean difference in follicle counts was computed, and a 1‐sample Student t test was performed to test the hypothesis that the mean of the differences was 0. Comparison of the 2 methods and observers by Bland‐Altman plots was used to determine any systematic differences based on the total number of follicles per selected ovary. Results. Mean differences differed from 0 (P < .005) for all 3 comparisons: 2D RDMS versus 3D RDMS, 2D RDMS versus 3D PI, and 3D RDMS versus 3D PI. For the comparison of 2D versus 3D counts done by the RDMS, 5 ovaries (10%) had a difference of more than 5 follicles counted; for the 2D RDMS versus 3D PI, 11 ovaries (22%) had a difference of more than 5 follicles; for the 3D RDMS versus 3D PI, 8 ovaries (16%) had a difference of more than 5 follicles. Mean differences in counts ranged 0.29 to 1.04 for ovaries with 10 or fewer follicles compared with 3.94 to 9.00 for ovaries with more than 10 follicles. Conclusions. Follicle counts using 3D volumes were similar to 2D counts, and 3D follicle counts done by an inexperienced operator were similar to counts done by an experienced sonographer.     

Influence of Gain Adjustment on 3‐Dimensional Power Doppler Indices and on Spatiotemporal Image Correlation Volumetric Pulsatility Indices Using a Flow Phantom

Spatiotemporal image correlation can be used to acquire 3‐dimensional power Doppler information across a single cardiac cycle. Assessment and comparison of the systolic and diastolic components of the data sets allow measurement of the recently introduced “volumetric pulsatility index” (vPI) through algorithms comparable with those used in 2‐dimensional Doppler waveform analysis. The vPI could potentially overcome the dependency on certain machine settings, such as power, color gain, pulse repetition frequency, and attenuation, since these factors would affect the power Doppler signal equally throughout the cardiac cycle. The objective of this study was to compare the effect of color gain on the vascularization index (VI), vascularization‐flow index (VFI), and vPI using an in vitro flow phantom model. We separated gains into 3 bands: ?8 to ?1 (no noise), ?1 to +5 (low noise), and +5 to +8 (obvious noise). The vPI was determined from the 3‐dimensional VI or VFI using the formula vPI = (maximum ? minimum)/mean. Using no‐noise gains, we observed that although the VI and VFI increased linearly with gain, the vPI was substantially less dependent on this adjustment. The VI and VFI continued to increase linearly with gain, whereas the vPI decreased slightly using low‐noise gains. When gain was increased above the lower limit of obvious noise (+5), the VI and VFI increased noticeably, and there were marked reductions in both vPI values. We conclude that the vPI is less affected by changes in color gain than the VI and VFI at no‐noise gains.     

Reproducibility of Placental Volume and Vasculature Indices Obtained by 3‐Dimensional Power Doppler Sonography

Objective. The purpose of this study was to evaluate the reproducibility of 3‐dimensional (3D) power Doppler assessment of placental volumes and vascularization before adopting these in routine evaluation of normal and complicated pregnancies. Methods. A prospective study was performed on 30 normal singleton pregnancies from 11 to 14 weeks. To evaluate placental vascularization, 3D power Doppler sonography was applied to obtain a placental volume, and the volume acquired was analyzed using virtual organ computer‐aided analysis. Two consecutive measurements were taken from each patient by two observers blinded to each other's and the individual's previous measurement. This yielded a total of 60 data set pairs. The placental volume, vascularization index, flow index, and vascularization‐flow index (VFI) were calculated. Normal distribution of the data was confirmed with the Kolmogorov‐Smirnov test. Intraobserver and interobserver correlations were evaluated. Bland‐Altman plots and statistics were used to compare the 95% limits of agreement between measurements. Results. All 3D power Doppler placental volumes and vascular indices showed intraobserver correlations of 0.80 or higher. Similar excellent interobserver correlations were seen for all indices with the exception of the VFI, which showed a lower but acceptable correlation. The Bland‐Altman analyses indicated good reproducibility of the evaluated placental indices. Conclusions. Our findings provide validation of the technique, showing good reproducibility of the 3D power Doppler parameters when applied to studies of the placental volume and vascular tree.     

Reproducibility of pulsed Doppler measurements of the maternal renal circulation in normal pregnancies and those with pregnancy-induced hypertension.

OBJECTIVE: To assess the inter- and intraobserver reproducibilities of pulsed Doppler measurements of the maternal renal circulation in normal pregnancies and those affected by pregnancy-induced hypertension. MATERIALS AND METHODS: Color and pulsed Doppler ultrasound was used to measure acceleration time and resistance index in the renal segmental and interlobar arteries. For the investigation of interobserver reproducibility, two sonographers performed measurements blindly in six normal pregnant women and 14 women with pregnancy-induced hypertension between 28 and 36 weeks' gestation. A second group of 10 patients between 30 and 35 weeks' gestation were examined by one sonographer to assess the level of intraobserver reproducibility of measurements. For each patient in this group, the flow waveform was measured three times in succession. Calculations of the intraclass correlation coefficient Ri were used to determine the level of reproducibility. RESULTS: The interobserver Ri and intraobserver Ri for acceleration time in the segmental artery were 0.95 and 0.96 and for the interlobar artery they were 0.97 and 0.98, respectively. For the resistance index, these values were 0.01 and 0.01 in the segmental artery and 0.52 and 0.29 in the interlobar artery. CONCLUSION: Both the inter- and intraobserver reproducibility of acceleration time measurements in the renal segmental and interlobar arteries were clinically acceptable but the equivalent reproducibilities of resistance index measurements were poor.     

B-flow sonographic evaluation of hemodialysis fistulas: a comparison with low- and high-pulse repetition frequency color and power Doppler sonography.

OBJECTIVE: The purpose of this study was to determine the effectiveness of B-flow sonography in the evaluation of hemodialysis fistulas and to compare this new technique with color and power Doppler sonography. METHODS: In this study, 32 randomly selected patients (mean age, 46 years; age range, 18-87 years) with normally functioning hemodialysis fistulas were evaluated with low- and high-pulse repetition frequency (PRF) color and power Doppler sonography (PRF values of 3 and 10 kHz) and B-flow sonography. All images were reviewed and graded independently by 2 observers for luminal filling with flow signals, visibility of the intimal layer, and overall image quality. The study was approved by the Institutional Review Board, and informed consent was obtained from all patients. RESULTS: Statistical analysis with Friedman and Wilcoxon signed rank tests revealed that B-flow sonography was superior to other techniques for luminal filling and visibility of the intimal layer (P = .000). For overall image quality, B-flow sonography was also the best method according to the Friedman test (P = .000). However, the Wilcoxon test showed no significant difference between B-flow and high-PRF (10-kHz) color and power Doppler sonography (P = .131). The kappa scores reflected moderate to good interobserver agreement (kappa = 0.285-0.784). CONCLUSIONS: B-flow sonography is a relatively new and superior imaging technique that provides direct visualization of the blood echoes and the morphologic characteristics of the surrounding vessel wall simultaneously. During the evaluation of hemodialysis shunts, the major advantage of this technique is its ability to avoid artifacts such as aliasing and overwriting.     

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.     

Three‐Dimensional Vascular Indices Calculated Using Conventional Power Doppler and High‐Definition Flow Imaging

Objective. The purpose of this study was to determine whether there are differences in 3‐dimensional (3D) vascular indices when calculated using high‐definition flow imaging (HDF) and power Doppler imaging (PD). Methods. Twenty‐five consecutive asymptomatic premenopausal women (mean age, 31 years; range, 28–33 years) without a history of gynecologic disease who attended routine gynecologic checkups were included in the study. All women had regular menstrual cycles, and none had uterine or myometrial disease detected on basal transvaginal sonography. All women underwent 3D transvaginal sonography. In each patient, a first volume using conventional PD was obtained, immediately followed by a second volume using HDF. Volumes were stored and subsequently analyzed for calculating 3D vascular indices (vascularization index [VI], flow index [FI], and vascularization‐flow index [VFI]) from the endometrium. Results. The median VI, FI, and VFI were significantly higher when calculated using HDF compared with conventional PD (P < .05). Conclusions. Three‐dimensional vascular indices calculated using HDF are higher than those calculated using conventional PD.