Conventional Color Doppler Imaging Research Articles

Transabdominal ultrasound evaluation of vascularity of gallbladder lesions: particularly those with wall thickening.

Gallbladder wall thickening is relatively common in clinical settings, and for appropriate diagnosis, the size, shape, internal structure, surface contour, and vascularity of the gallbladder wall must be evaluated. Morphological evaluation is the most important; however, some gallbladder lesions resemble gallbladder cancer in imaging studies, making differential diagnosis challenging. Vascular evaluation is indispensable for a precise diagnosis in these cases. In this review, we present the current status of vascular evaluation using US and diagnosis using vascular imaging for gallbladder lesions, including those presenting with wall thickening. To date, several ultrasound imaging techniques have been developed to assess vascularity, including Doppler imaging with high sensitivity, use of contrast agents, and microvascular imaging using a novel filter for Doppler imaging. Although conventional color Doppler imaging is rarely used for the diagnosis of gallbladder lesions, the efficacy of contrast-enhanced ultrasound in assessing the vascularity, enhancement pattern, or timing of enhancement/washout has been reported. Presence of multiple irregular microvessels has been speculated to indicate malignancy. However, few reports on microvessels have been published, and further studies are required for the precise diagnosis of gallbladder lesions with microvascular evaluation.

Current Developments and Role of Intestinal Ultrasound including the Advent of AI.

Intestinal ultrasound is a non-invasive, safe, and cost-effective technique to study the small and large intestines. In addition to conventional B-mode and color doppler imaging, new US tools have been developed in more recent years that provide auxiliary data on many GI conditions, improving the diagnosis and assessment of relevant outcomes. We have reviewed the more recent literature (from 2010 onwards) on auxiliary tools in bowel ultrasound such as elastography techniques, CEUS, SICUS, and the potential contribution by artificial intelligence (AI) to overcome current intestinal ultrasound limitations. For this scoping review, we performed an extensive literature search on PubMed and EMBASE to identify studies published until December 2023 and investigating the application of elastography techniques, CEUS, SICUS, and AI in the ultrasonographic assessment of the small and large intestines. Multiparametric intestinal ultrasound shows promising capabilities in Crohn's disease, while less is known about the role in ulcerative colitis. Despite some evidence, the CEUS role as a point-of-care examination tool for rare conditions such as intestinal GvHD and ischemic small bowel disease seems promising, possibly avoiding the need to perform further cross-sectional imaging. The use of AI in intestinal ultrasound is still anecdotical and limited to acute appendicitis.

Intracardiac Flow Analysis of the Right Ventricle in Pediatric Patients With Repaired Tetralogy of Fallot Using a Novel Color Doppler Velocity Reconstruction

Repaired tetralogy of Fallot (RTOF) patients will develop right ventricular (RV) dysfunction from chronic pulmonary regurgitation (PR). Cardiac magnetic resonance sequences such as four-dimensional flow can demonstrate altered vorticity and flow energy loss (FEL); however, they are not as available as conventional echocardiography (echo). The study determined whether a novel, vendor-independent Doppler velocity reconstruction (DoVeR) could measure RV intracardiac flow in conventional echo of RTOF patients. The primary hypothesis was that DoVeR could detect increased vorticity and diastolic FEL in RTOF patients. Repaired tetralogy of Fallot patients with echo were retrospectively paired with age-/size-matched controls. Doppler velocity reconstruction employed the stream function-vorticity equation to approximate intracardiac flow fields from color Doppler. A velocity field of the right ventricle was reconstructed from the apical 4-chamber view. Vortex strength (VS, area integral of vorticity) and FEL were derived from DoVeR. Cardiac magnetic resonance and exercise stress parameters (performed within 1year of echo) were collected for analysis. Twenty RTOF patients and age-matched controls were included in the study. Mean regurgitant fraction was 40.5%±7.6%, and indexed RV end-diastolic volume was 158±36mL/m2. Repaired tetralogy of Fallot patients had higher total, mean diastolic, and peak diastolic VS (P=.0013, P=.0012, P=.0032, respectively) and higher total, mean diastolic, and peak diastolic body surface area-indexed FEL (P=.0016, P=.0022, P<.001, respectively). Peak diastolic indexed FEL and peak diastolic VS had weak-to-moderate negative correlation with RV ejection fraction (r=-0.52 [P=.019] and r=-0.49 [P=.030], respectively) and left ventricular ejection fraction (r=-0.47 [P=.034] and r=-0.64 [P=.002], respectively). Mean diastolic indexed FEL and VS had moderate-to-strong negative correlation with percent predicted maximal oxygen consumption (r=-0.69 [P=.012] and r=-0.75 [P=.006], respectively). DoVeR can detect alterations to intracardiac flow in RTOF patients from conventional color Doppler imaging. Echo-based measures of diastolic VS and FEL correlated with ventricular function. DoVeR has the potential to provide serial evaluation of abnormal flow dynamics in RTOF patients.

Full-volume three-component intraventricular vector flow mapping by triplane color Doppler

Objective. Intraventricular vector flow mapping (iVFM) is a velocimetric technique for retrieving two-dimensional velocity vector fields of blood flow in the left ventricular cavity. This method is based on conventional color Doppler imaging, which makes iVFM compatible with the clinical setting. We have generalized the iVFM for a three-dimensional reconstruction (3D-iVFM). Approach. 3D-iVFM is able to recover three-component velocity vector fields in a full intraventricular volume by using a clinical echocardiographic triplane mode. The 3D-iVFM problem was written in the spherical (radial, polar, azimuthal) coordinate system associated to the six half-planes produced by the triplane mode. As with the 2D version, the method is based on the mass conservation, and free-slip boundary conditions on the endocardial wall. These mechanical constraints were imposed in a least-squares minimization problem that was solved through the method of Lagrange multipliers. We validated 3D-iVFM in silico in a patient-specific CFD (computational fluid dynamics) model of cardiac flow and tested its clinical feasibility in vivo in patients and in one volunteer. Main results. The radial and polar components of the velocity were recovered satisfactorily in the CFD setup (correlation coefficients, = 0.99 and 0.78). The azimuthal components were estimated with larger errors ( = 0.57) as only six samples were available in this direction. In both in silico and in vivo investigations, the dynamics of the intraventricular vortex that forms during diastole was deciphered by 3D-iVFM. In particular, the CFD results showed that the mean vorticity can be estimated accurately by 3D-iVFM. Significance. Our results tend to indicate that 3D-iVFM could provide full-volume echocardiographic information on left intraventricular hemodynamics from the clinical modality of triplane color Doppler.

Ultrasonographic Detection of Vascularity of Focal Breast Lesions: Microvascular Imaging Versus Conventional Color and Power Doppler Imaging.

To compare microvascular flow imaging (MVFI) to conventional Color-Doppler (CDI) and Power-Doppler (PDI) imaging in the detection of vascularity of Focal Breast Lesions (FBLs). A total of 180 solid FBLs (size: 3.5-45.2 mm) detected in 180 women (age: 21-87 years) were evaluated by means of CDI, PDI, and MVFI. Two blinded reviewers categorized lesion vascularity in absent or present, and vascularity pattern as (a) internal; (b) vessels in rim; (c) combined. The presence of a "penetrating vessel" was assessed separately. Differences in vascularization patterns (chi2 test) and intra- and inter-observer agreement (Fleiss method) were calculated. ROC analysis was performed to assess performance of each technique in differentiating benign from malignant lesions. About 103/180 (57.2%) FBLs were benign and 77/180 (42.8%) were malignant. A statistically significant (p < .001) increase in blood flow detection was observed for both readers with MVFI in comparison to either CDI or PDI. Benign FBLs showed mainly absence of vascularity (p = .02 and p = .01 for each reader, respectively), rim pattern (p < .001 for both readers) or combined pattern (p = .01 and p = .04). Malignant lesions showed a statistically significant higher prevalence of internal flow pattern (p < .001 for both readers). The prevalence of penetrating vessels was significantly higher with MVFI in comparison to either CDI or PDI (p < .001 for both readers) and in the malignant FBLs (p < .001). ROC analysis showed MVFI (AUC = 0.70, 95%CI = [0.64-0.77]) more accurate than CDI (AUC = 0.67, 95%CI = [0.60-0.74]) and PDI (AUC = 0.67, 95%CI = [0.60-0.74]) though not significantly (p = .5436). Sensitivity/Specificity values for MVFI, PDI, and CDI were 76.6%/64.1%, 59.7%/73.8% and 58.4%/74.8%, respectively. Inter-reader agreement with MVFI was always very good (k-score 0.85-0.96), whereas with CDI and PDI evaluation ranged from good to very good. No differences in intra-observer agreement were noted. MVFI showed a statistically significant increase in the detection of the vascularization of FBLs in comparison to Color and Power-Doppler.

Lateral Position-Dependent Velocity Estimation Error in Plane-Wave Doppler Ultrasound Systems

Doppler ultrasound has become a standard method used to diagnose and grade vascular diseases and monitor their progression. Conventional focused-beam color Doppler imaging is routinely used in clinical practice, but suffers from inherent trade-offs between spatial, temporal and velocity resolution. Newer, plane-wave Doppler imaging offers rapid simultaneous acquisition of B-mode, color and spectral Doppler information across large fields of view, making it a potentially useful method for quantitative estimation of blood flow velocities in the clinic. However, plane-wave imaging can lead to a substantial error in velocity estimation, which is dependent on the lateral location within the image. This is seen in both clinical and experimental plane-wave systems. In the work described in this article, we quantified this velocity error under different geometric and beamforming conditions using numerical simulation and experimental phantoms. We found that the lateral-dependent velocity errors are caused by asymmetrical geometric spectral broadening, and outline a correction algorithm that can mitigate these errors.

Additional Value of Superb Microvascular Imaging for Thyroid Nodule Classification with the Thyroid Imaging Reporting and Data System

Superb microvascular imaging (SMI) is an innovative vascular imaging technique for ultrasound (US). Compared with conventional color Doppler imaging (CDI) and power Doppler imaging (PDI), SMI can detect more blood flow in thyroid nodules. In this study, a total of 203 thyroid nodules (160 benign nodules, 43 malignant nodules) in 195 patients were assessed with the Thyroid Imaging Reporting and Data System (TI-RADS) published by the American College of Radiology in 2017) and SMI. With TI-RADS alone, 24 (15.0%), 76 (47.5%), 65 (40.6%) and 39 (24.4%) thyroid nodules were classified as TR2, TR3, TR4 and TR5, respectively. However, with the combination of TI-RADS and SMI, 31 (19.4%), 79 (49.4%), 44 (27.5%) and 49 (30.6%) thyroid nodules were classified as TR2, TR3, TR4 and TR5, respectively. The area under the receiver operating characteristic curves for the combination (0.952) was larger than that for TI-RADS alone (0.883) (Z = 3.478, p = 0.001). The efficiency of TI-RADS alone and the TI-RADS + SMI combination in diagnosing thyroid nodules was determined for all except TR2 nodules. Although no significant differences between the methods were observed for TR3 and TR5 thyroid nodules (p > 0.05), the diagnostic efficiency of TI-RADS + SMI for TR4 thyroid nodules was higher than that of TI-RADS alone for TR4 nodules (p < 0.05). This study indicated that the vascularity of thyroid nodules can be well characterized using SMI, and the combined use of gray-scale US and SMI can improve the diagnostic performance of TI-RADS for TR4 thyroid nodules.

4D simultaneous tissue and blood flow Doppler imaging: revisiting cardiac Doppler index with single heart beat 4D ultrafast echocardiography

The goal of this study was to demonstrate the feasibility of semi-automatic evaluation of cardiac Doppler indices in a single heartbeat in human hearts by performing 4D ultrafast echocardiography with a dedicated sequence of 4D simultaneous tissue and blood flow Doppler imaging.4D echocardiography has the potential to improve the quantification of major cardiac indices by providing more reproducible and less user dependent measurements such as the quantification of left ventricle (LV) volume. The evaluation of Doppler indices, however, did not benefit yet from 4D echocardiography because of limited volume rates achieved in conventional volumetric color Doppler imaging but also because spectral Doppler estimation is still restricted to a single location.High volume rate (5200 volume s−1) transthoracic simultaneous tissue and blood flow Doppler acquisitions of three human LV were performed using a 4D ultrafast echocardiography scanner prototype during a single heartbeat. 4D color flow, 4D tissue Doppler cineloops and spectral Doppler at each voxel were computed. LV outflow tract, mitral inflow and basal inferoseptal locations were automatically detected. Doppler indices were derived at these locations and were compared against clinical 2D echocardiography.Blood flow Doppler indices E (early filling), A (atrial filling), E/A ratio, S (systolic ejection) and cardiac output were assessed on the three volunteers. Simultaneous tissue Doppler indices e′ (mitral annular velocity peak), a′ (late velocity peak), e′/a′ ratio, s′ (systolic annular velocity peak), E/e′ ratio were also estimated. Standard deviations on three independent acquisitions were averaged over the indices and was found to be inferior to 4% and 8.5% for Doppler flow and tissue Doppler indices, respectively. Comparison against clinical 2D echocardiography gave a p value larger than 0.05 in average indicating no significant differences.4D ultrafast echocardiography can quantify the major cardiac Doppler indices in a single heart beat acquisition.

Visibility of the graft hepatic artery using superb microvascular imaging in liver transplantation recipients: initial experience.

Background Hepatic artery (HA) obstruction is one of the most threatening complications following liver transplantation (LT); however, conventional color Doppler imaging (CDI) suffers from technical limitations regarding the visualization of fine vessels and low-velocity blood flow. Purpose To test the visibility of HA in postoperative evaluation of LT using a superb microvascular imaging (SMI). Material and Methods This retrospective study was approved by our institutional review board. Fifty-five consecutive patients (58 grafts; mean age = 56 years) who underwent LT with Doppler ultrasonography (US) on postoperative day 1 were included. We compared the subjective visibility of HA and objective measurements of HA caliber, visible HA length on CDI, monochrome SMI (mSMI), contrast-enhanced mSMI (CE-mSMI), and contrast harmonic imaging (CHI). Reproducibility of HA caliber measurements on SMI techniques were also evaluated by using intraclass correlation coefficients (ICCs). Results The subjective image quality for visibility of HA tended to be graded higher with mSMI than CDI, and with CE-mSMI than mSMI ( P < 0.001). The overall reproducibility of HA caliber measurements was good to excellent for both mSMI and CE-mSMI (ICC = 0.674-0.855). HA caliber measurements on mSMI and CE-mSMI strongly correlated with CHI ( R = 0.785, 0.798, P < 0.001), while mean HA length on mSMI was significantly longer than on CDI (1.88 ± 0.83 vs. 1.42 ± 1.01cm, P = 0.004), and even longer on CE-mSMI (vs. 3.28 ± 1.11 cm, P < 0.001). Conclusion The mSMI technique shows good reproducibility and correlates well with currently used methods for postoperative evaluation of HA in LT recipients. It is further improved by administration of an US contrast agent.

A Comparison Between Compounding Techniques Using Large Beam-Steered Plane Wave Imaging for Blood Vector Velocity Imaging in a Carotid Artery Model.

Conventional color Doppler imaging is limited, since it only provides velocity estimates along the ultrasound beam direction for a restricted field of view at a limited frame rate. High-frame-rate speckle tracking, using plane wave transmits, has shown potential for 2-D blood velocity estimation. However, due to the lack of focusing in transmit, image quality gets reduced, which hampers speckle tracking. Although ultrafast imaging facilitates improved clutter filtering, it still remains a major challenge in blood velocity estimation. Signal dropouts and poor velocity estimates are still present for high beam-to-flow angles and low blood flow velocities. In this paper, ultrafast plane wave imaging was combined with multiscale speckle tracking to assess the 2-D blood velocity vector in a common carotid artery (CCA) flow field. A multiangled plane wave imaging sequence was used to compare the performance of displacement compounding, coherent compounding, and compound speckle tracking. Zero-degree plane wave imaging was also evaluated. The performance of the methods was evaluated before and after clutter filtering for the large range of velocities (0-1.5 m/s) that are normally present in a healthy CCA during the cardiac cycle. An extensive simulation study was performed, based on a sophisticated model of the CCA, to investigate and evaluate the performance of the methods at different pulse repetition frequencies and signal-to-noise levels. In vivo data were acquired of a healthy carotid artery bifurcation to support the simulation results. In general, methods utilizing compounding after speckle tracking, i.e., displacement compounding and compound speckle tracking, were least affected by clutter filtering and provided the most robust and accurate estimates for the entire velocity range. Displacement compounding, which uses solely axial information to estimate the velocity vector, provided most accurate velocity estimates, although it required sufficiently high pulse repetition frequencies in high blood velocity phases and reliable estimates for all acquisition angles. When this latter requirement was not met, compound speckle tracking was most accurate, because it uses the possibility to discard angular velocity estimates corrupted by clutter filtering. Similar effects were observed for in vivo data obtained at the carotid artery bifurcation. Investigating a combination of these two compounding techniques is recommended for future research.

An Innovative Ultrasound Technique for Evaluation of Tumor Vascularity in Breast Cancers: Superb Micro-Vascular Imaging.

Tumor vascularity is an important indicator for differential diagnosis, tumor growth, and prognosis. Superb micro-vascular imaging (SMI) is an innovative ultrasound technique for vascular examination that uses a multidimensional filter to eliminate clutter and preserve extremely low-velocity flows. Theoretically, SMI could depict more vessels and more detailed vascular morphology, due to the increased sensitivity of slow blood flow. Here, we report the early experience of using SMI in 21 breast cancer patients. We evaluated tumor vascular features in breast cancer and compared SMI and conventional color or power Doppler imaging. SMI was superior to color or power Doppler imaging in detecting tumor vessels, the details of vessel morphology, and both peripheral and central vascular distribution. In conclusion, SMI is a promising ultrasound technique for evaluating microvascular information of breast cancers.

Value of ultrasound elastography versus transrectal prostatic biopsy in prostatic cancer detection

ObjectiveTo detect the impact of ultrasound elastography in diagnosis of prostatic cancer, and to evaluate its capability in differentiating benign from malignant lesions. Materials and methodsFifty patients with different prostatic lesions suspicious for malignancy were included. All patients had a conventional B-mode ultrasound examination and color Doppler imaging, and then real time ultrasound elastography was performed in the same session. Finally, the results were compared to the histo-pathological results of those lesions. ResultsThe addition of Strain ratio parameter for evaluating the elastography images showed the highest sensitivity of 74.2%, specificity of 73.7% and accuracy of 74.0% at a best cutoff point of 5.5 between benign and malignant lesions. ConclusionBased on our results, prostate US combined with elastography can be a helpful tool for finding malignant lesions. Also it can help in targeting the biopsy site.

Abstract 15137: Vector Flow Mapping is a Novel Useful Technique in Assessing Inertia Force of Late Systolic Aortic Flow and Left Ventricular Early Diastolic Function

Background: We previously reported that the inertia force (IF) of blood flowing out of left ventricle (LV) during late-systole produces greater LV elastic recoil force and brings faster LV relaxation. Vector flow mapping (VFM TM , Hitachi-Aloka) enables us to see blood flow velocity vectors that are generated from conventional color Doppler imaging data at any phase of cardiac cycle without angle dependency. Using VFM, kinetic energy (KE) of ejecting blood flow during systole at the LV outflow tract (LVOT) can be obtained. Thus, we investigated whether the KE obtained at the LVOT during late systole (KE-ls) had any relations with the IF and invasively obtained LV function parameters. Method: Study subjects were 33 patients who underwent diagnostic cardiac catheterization and echocardiographic examination on the same day. Color Doppler images were acquired in the apical 3-chamber view. The frame rate ranged was from 40 to 51 frames per minute. Data analyses were performed offline using the commercially available software (DAS-RS1 TM, Hitachi-Aloka). A data sampling area was set at the level just below the aortic valve in the LVOT. The KE-ls was computed as the sum of KE values computed in frame by frame basis during late-systole; late-systole was defined as the latter one-third of ejecting time. LV pressure wave was obtained using a catheter-tipped micromanometer, and then, the first derivative of LV pressure (dP/dt) and a time constant τ of LV pressure decay during isovolumic relaxation were calculated. From LV pressure-dP/dt relationships (phase loop), the IF was determined. Results: A significant positive correlation was observed between the KE-ls and the IF (r=0.79, p&lt;0.0001). The log transformed KE-ls had significant correlations with both peak negative dP/dt (r=0.53, p&lt;0.01) and the time constant τ (r=-0.67, p&lt;0.0001). Conclusion: VFM is a new useful technique to see blood flow in the LV chamber. Noninvasively obtained KE-ls using VFM, which may be a noninvasive surrogate for the IF, has significant correlations with the parameters of LV relaxation.

Comprehensive Case Report Of A Giant Cell Tumor Involving The Proximal Phalanx Of The Left Great Toe Managed With Fibular Grafting

Giant cell tumors (GCT) involving the phalangeal bones of the foot are very rare: only 1-2% cases of GCT occur in the foot and are more common in females. We present a rare case of a benign giant cell tumor involving the proximal phalanx of the left great toe in a 23 year old male. The patient presented with a 3 month history of pain and gradually increasing swelling over the great toe of the left foot following trivial trauma to the foot while playing cricket. This case report aims to highlight the conventional radiographic, ultrasound and color Doppler, computed tomography and magnetic resonance imaging (MRI) findings in a rare case report of a giant cell tumor involving the proximal phalanx of the left great toe managed with fibular grafting.

Does a New Ultrasound Flow Modality Improve Visualization of Neonatal Pulmonary Veins?

Blood flow imaging is a new ultrasound modality that supplements color Doppler imaging with angle-independent information of flow direction that is not influenced by velocity aliasing. This is done by visualizing the blood speckle movement superimposed on the color Doppler images. This study aimed to investigate whether this method improves the visualization of the pulmonary veins in neonates. Twenty-six neonates with suspected congenital heart disease were prospectively examined with echocardiography and blood flow imaging of the pulmonary veins after parental consent. For each patient, blood flow imaging and color Doppler imaging cine loops were presented to four observers (pediatric cardiologist/cardiologists) in a random order. Questions regarding the pulmonary venous connections and the overall quality of the pulmonary vein imaging were evaluated on a visual analogue scale from 0 (worst) to 100 (best). The methods were compared within each observer using the Wilcoxon's exact signed-rank test. Blood flow imaging (color Doppler imaging combined with the blood speckle movement) was consistently ranked as better than conventional color Doppler imaging for visualization of the pulmonary veins for all observers (all P-values < 0.002). Blood flow imaging may improve the visualization of the pulmonary veins in neonates.

Sonographic hemodynamic evaluation of spleno-renal shunt using the Valsalva maneuver.

The purpose of this study was to assess the characteristic features of hemodynamic changes in portal venous hypertension with spleno-renal shunt on conventional B-mode and color Doppler imaging before and after the Valsalva maneuver. A total of 11 patients with portal venous hypertension underwent conventional B-mode and color Doppler ultrasound during follow-up examinations. Sonographic imaging of the splenic vein and the left renal vein was performed before and after the Valsalva maneuver. In the six patients with spleno-renal shunt formation, dilated left renal veins were depicted after the Valsalva maneuver. In the five patients without spleno-renal shunt, there was no apparent dilatation of the left renal vein either before or after the Valsalva maneuver. In all six patients with spleno-renal shunt, color flow mapping of the left renal veins was emphasized during the Valsalva maneuver. In the five patients without spleno-renal shunt formation, there were no apparent changes on color flow mapping of the left renal vein before or after the Valsalva maneuver. The sonographic findings of the splenic vein and the left renal vein on conventional B-mode and color Doppler imaging before and after the Valsalva maneuver are useful for diagnosis of spleno-renal shunt and for grading the hemodynamic changes caused by spleno-renal shunt.

Prenatal Diagnosis of Morbidly Adherent Placenta with 2D Ultrasonography, 3D Color Power Doppler and Magnetic Resonance Imaging

Abstract The incidence of placenta accreta/percreta should rise steadily over the next century as the frequency of cesarean sections and advanced maternal age, both independent risk factors, increases. Patients who are at risk should be identified. The diagnosis of placenta previa accreta/percreta is possible by using gray-scale sonography, conventional color Doppler imaging and MRI through studying the relation of placenta to the uterine wall and nearby pelvic structures. The potentially new modality of 3D and 3D color power Doppler ultrasound has it's value as a tool to achieve significantly increased diagnostic accuracy in the prediction of massive hemorrhage by assessing the extent, location and quantification of abnormal uteroplacental neovascularization. Hence, 3D ultrasound has the potential for providing additional information over conventional 2D ultrasound studies in the diagnosis of placenta previa percreta. The diagnosis and anticipation of the problem achieve the best results for the obstetrician and the patient.

Abstract 4734: Echodynamography is a Novel Useful Technique in Assessing Inertia Force of Late Systolic Aortic Flow and Left Ventricular Early Diastolic Function

We previously reported that the inertia force (IF) of the blood flowing out of left ventricle (LV) during late systolic phase produces greater LV elastic recoil force and brings faster LV relaxation. Echodynamography (ALOKA) is a novel technique that enables us to obtain the flow velocity vector from conventional color Doppler velocity data on the range of interest at any phase of cardiac cycle without angle dependency. We investigated whether the flow velocity vector obtained at LV outflow tract (LVOT) in late systole had a relation with IF and invasively obtained LV relaxation parameters. Method: Study subjects were consecutive 26 patients who underwent diagnostic cardiac catheterization and conventional color Doppler imaging on the same day. Color Doppler image was acquired in the apical 3-chamber view. The analyses for flow velocity vector were performed offline using an echo image analyzer. The late systolic velocity of the blood flowing was obtained as an average value of the L VOT (V LVOT −late systole). LV pressure was obtained using a catheter-tipped micromanometer. From the recorded pressure waves, first derivative of LV pressure (dP/dt) and a time constant τ of LV pressure decay during isovolumic relaxation were calculated. From LV pressure-dP/dt relationships (phase loop), IF was determined. Results: A significant positive correlation was observed between the V LVOT -late systole and IF (r=0.75, p&lt;0.0001). The V LVOT -late systole also had significant correlations both with peak negative dP/dt (r=0.49, p&lt;0.05) and the time constant τ (r=−0.70, p&lt;0.0001). Conclusion: This study indicates that the V LVOT -late systole, which may be a noninvasive substitute for IF, has significant correlations with the parameters of LV relaxation. Echodynamography is a new useful technique to estimate LV early diastolic function.

Improved Differentiation of Pancreatic Tumors Using Contrast-Enhanced Endoscopic Ultrasound

Endoscopic ultrasound is a widely accepted imaging method for staging of ductal adenocarcinoma and the localization of neuroendocrine tumors of the pancreas. We prospectively evaluated conventional color Doppler imaging and contrast-enhanced endoscopic Doppler ultrasound (CE-EDUS) as a new imaging technique for further characterization and differentiation of solid pancreatic tumors. From 300 patients with pancreatic lesions investigated using contrast-enhanced endoscopic ultrasound we could finally include 93 patients with an undetermined, solitary, predominantly solid, lesion 40 mm or less, and a definite histologically proven diagnosis. After bolus injection of the contrast agent SHU 508A 4 g (400 mg/dL) the vascular pattern of the lesion during the arterial phase was compared with the vascularity of the residual pancreatic parenchyma. Color Doppler imaging did not reveal vascularity of the pancreatic parenchyma in any of the patients, and therefore tumor hypovascularity could not be determined in contrast to all CE-EDUS-examined patients revealing at least some degree of parenchymal vascularity. Fifty-seven of 62 patients with ductal adenocarcinoma of the pancreas showed a hypovascularity of the tumor using CE-EDUS. All other pancreatic lesions revealed an isovascular or hypervascular pattern using contrast-enhanced endoscopic ultrasound (20 neuroendocrine tumors, 10 serous microcystic adenomas, and 1 teratoma). Hypovascularity as a sign of malignancy in contrast-enhanced endoscopic ultrasound obtained 92% (82%-97%) sensitivity and 100% specificity (89%-100%). Contrast-enhanced endoscopic ultrasound is effective in differentiating small solid pancreatic tumors of different origin in most cases. Hypovascularity indicates malignancy of pancreatic tumors.

Conventional and color Doppler sonography in preoperative assessment of ovarian tumors

Objective: To study the vascular patterns of ovarian tumors by color Doppler imaging (CDI) and compare the findings of conventional sonographic studies and CDI with histopathologic findings for the same tumors. Methods: Fifty nonpregnant women scheduled for elective surgery for ovarian tumors were examined by sonographic scanning and CDI by the same physician. Sonographic morphology scores [SMSs] were used, and the pulsatility index (PI) and resistance index (RI) were calculated after locating vessels in and around the tumors by CDI. Results: It was possible to obtain CDI results in 26 of the 50 women. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 100%, 71.43%, 73.33%, and 100%, respectively, for SMS. With CDI, the sensitivity, specificity, PPV, and NPV were 100%, 85.72%, 95%, and 100% for PI and 100%, 71.43%, 90.48%, and 100% for RI. RI sensitivity and specificity were identical to those of SMS, i.e., 100% and 71.43%, respectively, but PI specificity was better (85.72%). Conclusion: In this study, CDI was definitely better than SMS when color flow could be obtained through the tumors. The overall efficiency in diagnosing the nature of tumors is very high if SMS and CDI are both used in patients having ovarian tumors.