Color Doppler Energy Imaging Research Articles

Hybrid descriptor for placental maturity grading

Placental maturity grading (PMG) is quite essential to assess fetal growth and maternal health. To this date, PMG has mostly relied on the subjective judgment of the clinician, which is time-consuming and may cause wrong estimation due to redundancy and repeatability of the process. To tackle it, we propose an automatic method to stage placental maturity via deep hybrid descriptors based on B-mode ultrasound (BUS) and color Doppler energy (CDE) images. Specifically, convolutional descriptors extracted from multiple deep convolutional neural networks (DCNNs) and hand-crafted features are integrated to get the hybrid descriptors for grading performance boosting. First, different models with various feature layers are combined to obtain hybrid descriptors from images. Second, the transfer learning strategy is also utilized to enhance the grading performance via the deeply represented features. Third, extracted descriptors are encoded by Fisher vector (FV). Finally, we use support vector machine (SVM) as the classifier to grade placental maturity. The experimental results demonstrate that our proposed method could achieve good performance in PMG.

Role of Color Doppler and Three-dimensional Ultrasound in Infertility

Color Doppler is emerging as a valuable diagnostic imaging modality in the field of medicine, primarily infertility. Reproductive disorders, including infertility and spontaneous abortions/miscarriages, have emerged as major public health problem(s) worldwide. Color Doppler energy imaging is a high throughput technology based on the total integral of energy frequency spectrum. Color Doppler is a high-throughput, sophisticated imaging technique for the assessment of uterine anomalies, intrauterine pathology, tubal patency, polycystic ovaries, ovarian follicular monitoring, endometrial receptivity, failed or an ectopic pregnancy, male infertility and uterine, endometrial and ovarian vascularity. Assessments of the utero-ovarian pulsatility indices (PIs), resistance indices (RIs), and endometrial color signals are important determinants of in vitro fertilization (IVF) cycles and pregnancy rates. With many clinical/scientific research experience in the field of reproductive medicine, I strongly believe that an overall public health model needs to be designed in managing infertility patients; therefore, major issues such as cost effectiveness and technical artifacts should address so as to achieve an accurate clinical diagnosis, successful IVF outcome/pregnancy, and overall patient satisfaction in a clinical rehearse setting. Simple, safe efficient and affordable diagnostic modalities should be incorporated at infertility clinics coupled with well-designed patient counseling sessions and community-based public health awareness campaigns conducted so as to reduce the morbidity and mortality rates associated with reproductive disorders. Three dimension (3-D) ultrasound is a new imaging modality which is being introduced into clinical practice. It has been proved that 3-D ultrasound is a very highly reproducible technique. With 3-D ultrasound, a volume of a region of interest can be acquired and stored. This volume can be further analyzed in several ways, such as navigation, multiplanar display and surface rendering or volume calculation. Power Doppler ultrasound, in combination with 3-D ultrasound, allows for a whole assessment of relevant vessels and quantitative assessment of vessel density and perfusion within a specified area. Faridpur Med. Coll. J. Jul 2018;13(2): 97-100

Specific features of joint ultrasound study in patients with rheumatoid arthritis

To study the specific features of joint ultrasound readings in rheumatoid arthritis (RA) in relation to its duration. A total of 162 patients (mean age, 43.54±11.1 years) with a mean RA duration of 3.22±3.13 years were examined. Gray-scale ultrasound study (USS) of hand and ankle joints was performed using color Doppler energy imaging. Group 1 included 78 patients with a RA duration of less than 2 years; Group 2 consisted of 84 patients with a RA duration of more than 2 years. Joint USS diagnosed osteochondral erosions twice more frequently than conventional radiography. 82% of the patients with RA were found to have synovitis; 77% had thickening of the synovial membrane (SM) with hypervascularization, the vascularization intensity scores of 2-3 being predominant; and 54% had tenosynovitis of the carpal extensor tendon. Effusion into the joint cavity, SM hypervascularization scores of 2-3, and tenosynovitis were most common in Group 1. SM thickening and osteochondral erosions were prevalent in Group 2. Joint USS revealed that angiogenesis and inflammation were dominant in the patients with a RA duration of less than 2 years and the proliferative-destructive processes were prevalent in those with a RA duration of more than 2 years. Identifying the predominance of pathophysiological processes in each specific patient with RA will be able to individualize therapy and to improve the prognosis of the disease.

Automatic placental maturity grading via hybrid learning

Fetal viability, gestational age, and complicated image processing have made evaluating placental maturity a tedious and time-consuming task. Despite various developments, automatic placental maturity still remains as a challenging issue. To address this issue, we propose a new method to automatically grade placental maturity from B-mode ultrasound (BUS) and color Doppler energy (CDE) images based on a hybrid learning architecture. We also apply an improved pyramidal shift invariant feature transform (IPSIFT) descriptor using a coarse-to-fine scale representation for visual feature extraction. These local features are then clustered by a generative Gaussian mixture model (GMM) to incorporate high order statistics. Next, the clustering representatives are encoded and aggregated via Fisher vector (FV). Instead of using traditional FV, an end-to-end deep training strategy is developed to fine-tune the GMM parameters to boost evaluation performance. A multi-view fusion technique is also developed for feature complementarity exploration. Extensive experimental results demonstrate that our method delivers promising performance in placental maturity evaluation and outperforms competing methods.

Multi-modal and multi-layout discriminative learning for placental maturity staging

Placental maturity staging is a challenging task due to complex imaging procedure, fetal and gestational age variations. To address this issue, we extract features not only from B-mode gray-scale ultrasound (US) images, but also from color Doppler energy (CDE) images. Based on these features, we propose a method to automatically determine the placental maturity by harnessing multi-view and multi-layout discriminative learning fusion. Specifically, we devise a multi-view technique to generate features of complementary information. Scale invariant features are extracted from image locally, and a Gaussian mixture model (GMM) is then applied to summarize the high-level information features. The clustering representatives from GMM are encoded via a multi-layout Fisher vector (MFV) instead of traditional Fisher vector (FV) to aggregate features based on their spatial information. We apply a multi-layout feature encoding method to improve the staging performance using discriminative learning technique. Extensive experimental results demonstrate that our method achieves promising performance in placental maturity staging and outperforms existing methods.

Emerging role of Color Doppler in Infertility Management: A Public Health perspective

Color Doppler is emerging as a valuable diagnostic imaging modality in the field of reproductive medicine, primarily infertility. Reproductive disorders, including infertility and spontaneous abortions/miscarriages, have emerged as major public health problem(s) worldwide. Color Doppler energy imaging is a high throughput technology based on the total integral of energy frequency spectrum. We extracted the most relevant articles (comprehensive reviews and original research articles) for inclusion in our review by performing a comprehensive literature search using the Pubmed (last accessed on 2015 April 28) scientific database. Color Doppler is a high-throughput, sophisticated imaging technique for the assessment of uterine anomalies, intrauterine pathology, tubal patency, polycystic ovaries, ovarian follicular monitoring, endometrial receptivity, failed and/or ectopic pregnancy, male infertility, and uterine, endometrial, and ovarian vascularity. Assessments of the uteroovarian pulsatility indices (PIs), resistance indices (RIs), and endometrial color signals are important determinants of in vitro fertilization (IVF) cycles and pregnancy rates. With our clinical/scientific research experience in the field of reproductive medicine, we strongly believe that an overall public health model needs to be designed in managing infertility patients; therefore, major issues such as cost-effectiveness and technical artifacts should be addressed so as to achieve an accurate clinical diagnosis, successful IVF outcome/pregnancy, and overall patient satisfaction in a clinical research setting. Simple, safe, efficient, and affordable diagnostic modalities should be incorporated at infertility clinics coupled with well-designed patient counseling sessions and community-based public health awareness campaigns conducted so as to reduce the morbidity and mortality rates associated with reproductive disorders.

Natural history of periocular capillary haemangiomas: changes in internal blood velocity and lesion volume

Although the clinical characteristics of childhood periocular capillary haemangiomas are well known, serial measurements of blood velocity and lesion size are unknown. This investigation was designed to measure the changes in maximum blood velocity and estimated size of lesion in children with capillary haemangioma not requiring active intervention. Retrospective case-note review for a cohort of children with capillary haemangioma involving the eyelid and orbit. Children with periocular capillary haemangioma, under the care of the Orbital unit at Moorfields Eye Hospital between 1996 and 2005, were monitored clinically and with repeated ultrasonographic examination. Volume estimates were calculated as an ovoid based on the three maximum orthogonal measurements for the haemangioma, and blood velocity was assessed by Colour Flow Mapping, Colour Doppler Energy Imaging, and Spectral Doppler techniques using a Sequoia 512 Acuson scanner. Twenty-four children (12 boys) had initial assessment by 18 months of age, and the haemangioma increased in size in 14/24 (58%), the increase being between 4 and 931% of initial volume estimate. The largest measured size for an individual haemangioma appears inversely related to the child's age at measurement, this mirroring a similar trend in measurements for the maximum blood velocity. Blood velocity measurements also tend to decrease with time, the peak velocity being before 1 year of age in the majority (15/24; 62%). In many children, both volume estimates and blood velocities show a cyclic variation-this occurring with increasing intervals between the maxima, before a final decay in both parameters. Although, for the whole group, there was no correlation (correlation coefficient=0.29) between estimated size and measured blood velocity, some individual children showed a significant correlation between the two parameters. The age at maximum blood velocity appeared to precede the age at maximum volume in most children, and in many there was an orbital anomaly detectable on ultrasonographic examination, even with complete clinical resolution of the haemangioma. Ultrasonographic examination of periocular capillary haemangiomas show that these lesions have a very high blood velocity in feeding vessels-about 2-3 orders of magnitude greater than normal capillary beds-and that the velocity and volume of such lesions undergo a cyclic variation during their natural history. Evidence suggests that both velocity and volume decrease with time, although often not returning to zero on ultrasonography (unlike the clinical resolution of the lesions). In most children, blood velocity peaks before volume estimates and this might suggest that decreasing perfusion leads to later tissue atrophy and involution of the haemangioma.

A systematic review of the accuracy of ultrasound in the diagnosis of endometriosis.

To evaluate transvaginal and transabdominal ultrasound scanning, with or without Doppler, as a diagnostic test for the accurate diagnosis of pelvic endometriosis. The MEDLINE (1966-2001) and EMBASE (1980-2001) databases were searched for relevant studies, published in English. Only studies fulfilling predefined criteria were selected. An assessment of quality was made for each study, and data were then reanalyzed using likelihood ratios to determine the usefulness of the test. In total, 67 papers were identified using the search strategy, of which 17 described relevant studies. Of these, seven fulfilled the inclusion criteria. All seven related to the use of transvaginal gray-scale imaging in the diagnosis of ovarian endometriomata specifically, rather than endometriosis. The positive likelihood ratios ranged from 7.6 to 29.8, and the negative likelihood ratios ranged from 0.1 to 0.4. Confidence intervals were wide. One paper addressed the use of conventional color Doppler with ultrasound: the positive likelihood ratio was 1.2, with a negative likelihood ratio of 0.4. One paper assessed the use of color Doppler energy imaging, and showed a positive likelihood ratio of 33.5 and a negative likelihood ratio of 0.1. Transvaginal ultrasound appears to be a useful test both to make and to exclude the diagnosis of an ovarian endometrioma.

ENHANCED VISUALISATION OF THE NORMAL PROSTATE BLOOD FLOW IN YOUNG HEALTHY VOLUNTEERS USING A NEW ULTRASOUND CONTRAST AGENT

To evaluate the sonographic appearance of normal prostate vascularity before and after injection of a new ultrasound contrast agent, Sonazoid (NC100100, Nycomed Amersham). Five healthy male volunteers were given three injections of Sonazoid each. Transrectal B-mode, colour Doppler and colour Doppler energy (i.e. power Doppler) imaging was performed. The visibility of the vascular pattern and the vascular architecture of the prostate, including dynamics of contrast inflow and blood flow symmetry, were evaluated. The depiction of the vascularity was improved in all subjects after injection of Sonazoid for both Doppler modes. No improvement was seen for B-mode. Contrast dynamics within the prostate vessels were demonstrated with a mean time from injection of the ultrasound contrast agent to enhancement of the Doppler signals in the subcapsular arteries of 14+/-1 s (11--17 s), and the ultrasound contrast agent reached the central periurethral veins 4--7 s later. A symmetric, radial, spoke-like intraprostatic vascular pattern could be identified in all subjects using power Doppler imaging and ultrasound contrast agent. Sonazoid improved the detection of normal human prostate vascular anatomy for both colour and power Doppler imaging. Contrast dynamic studies revealed a radial spoke-like intraprostatic vascular pattern. This information might be useful in examination of patients with suspicion of prostate cancer, and needs to be further investigated.

Enhanced visualisation of the normal prostate blood flow in young healthy volunteers using a new ultrasound contrast agent

Purpose: To evaluate the sonographic appearance of normal prostate vascularity before and after injection of a new ultrasound contrast agent, Sonazoid (NC100100, Nycomed Amersham). Material and Methods: Five healthy male volunteers were given three injections of Sonazoid each. Transrectal B-mode, colour Doppler and colour Doppler energy (i.e. power Doppler) imaging was performed. The visibility of the vascular pattern and the vascular architecture of the prostate, including dynamics of contrast inflow and blood flow symmetry, were evaluated. Results: The depiction of the vascularity was improved in all subjects after injection of Sonazoid for both Doppler modes. No improvement was seen for B-mode. Contrast dynamics within the prostate vessels were demonstrated with a mean time from injection of the ultrasound contrast agent to enhancement of the Doppler signals in the subcapsular arteries of 14±1 s (11-17 s), and the ultrasound contrast agent reached the central periurethral veins 4-7 s later. A symmetric, radial, spoke-like intraprostatic vascular pattern could be identified in all subjects using power Doppler imaging and ultrasound contrast agent. Conclusion: Sonazoid improved the detection of normal human prostate vascular anatomy for both colour and power Doppler imaging. Contrast dynamic studies revealed a radial spoke-like intraprostatic vascular pattern. This information might be useful in examination of patients with suspicion of prostate cancer, and needs to be further investigated.

The study of ovarian artery hemodynamics in patients with infertility by color Doppler energy.

Seventy-four cases of infertility were examined to study the hemodynamics of the bilateral ovarian arteries at 21st day during the corpus luteum phase by color Doppler energy(CDE) and color Doppler flow imaging (CDFI). All the patients were verified by laparoscopy, fallopian tube patency examination and ovarian function test. Twenty-two healthy women served as controls. The results showed that the difference of resistance index(RI) and pulsatility index (PI) of bilateral ovarian arteries between the infertility and the normal controls had statistical significance (P < 0.01), and the PI showed negative correlation with the thickness of endometrium (left side: r = 0.724, P < 0.01; right side: r = 0.756, P < 0.01). The results also showed that CDE was more sensitive than CDFI in displaying the ovarian arteries. It could be concluded that the elevated resistance of ovarian artery during the corpus luteum phase was one of the important factors that resulted in infertility.

Transvaginal ultrasonography associated with colour Doppler energy in the diagnosis of hydrosalpinx

The aims of this prospective study were to investigate the accuracy of B-mode transvaginal ultrasonography alone, using the typical finding of the presence of an elongated shaped mass with incomplete septa, in the screening of hydrosalpinx in women undergoing surgery for gynaecological diseases, and to determine the predictive value of this method combined with colour Doppler energy (CDE) imaging evaluation and CA125 concentrations in differentiating hydrosalpinx from other adnexal masses. In the first part of the study, 378 consecutive pre-menopausal non-pregnant women were submitted to transvaginal ultrasonography alone before surgery. In the second part of the study, 256 adnexal masses underwent transvaginal ultrasonography combined with CDE imaging evaluation associated with spectral Doppler analysis and plasma concentrations of CA125. Sensitivity and specificity for the ultrasonographic screening were 84.6 and 99.7% respectively, calculated for each adnexum (n = 756) and 93.3 and 99.6% respectively, calculated for each mass, for differentiating hydrosalpinx from other adnexal masses. The CDE imaging and the evaluation of CA125 plasma concentrations do not seem to increase the accuracy of B-mode transvaginal ultrasonography. Inter- and intra-observer agreement, expressed in terms of k-values, was high (0.87 and 0.93 respectively). In conclusion, transvaginal ultrasonography alone is a useful method of detection of hydrosalpinx.

Clinical applications of colour Doppler energy imaging in the female reproductive tract and pregnancy.

This review describes the usefulness of colour Doppler energy (CDE) (or power Doppler) imaging to measure vascularization in the female reproductive tract. CDE imaging is characterized by an increased sensitivity to flow, and thus may be useful in low-flow states and when optimal Doppler angles cannot be obtained. In addition, longer segments of vessels and more individual vessels can be visualized with CDE imaging. The role of CDE imaging in the evaluation of stromal vasculature in normal and in polycystic ovaries is described, and the relationship between follicular vascularity and outcome following in-vitro fertilization are discussed, together with the findings obtained from the evaluation of thecal arteriole of corpus luteum in early pregnancy. The fundamental role of CDE imaging in differentiation among ovarian masses is also reviewed. We summarize the role of CDE imaging in pregnancy, and describe two new applications of three-dimensional power Doppler sonography and the use of ultrasound contrast media. In conclusion, CDE imaging can replace conventional colour Doppler when the information on the direction of flow is not useful. Moreover, the technique appears superior to others for describing microvascular architecture and determining the presence or absence of flow.

The diagnosis of endometriomas using colour Doppler energy imaging.

We studied the role of colour Doppler energy (CDE) (or power Doppler) imaging in the differentiation between endometriomas and other adnexal masses in premenopausal non-pregnant women. A total of 170 consecutive patients with persistent adnexal masses was submitted to B-mode transvaginal ultrasonography associated with CDE imaging evaluation. Plasma concentrations of CA125 were measured before surgery. Using CDE imaging evaluation of vessel distribution, the occurrence of one of the following findings was considered to indicate the likely presence of endometrioma: (i) a round-shaped homogeneous hypoechoic 'tissue' of low-level echoes without papillary proliferations associated with 'poor' vascularization; (ii) a round-shaped homogeneous hypoechoic 'tissue' of low-level echoes with an echogenic portion in which no flow was detected. The overall agreement between the test result and the actual outcome was calculated using the k index. The CDE imaging evaluation was more accurate in the diagnosis of endometriomas compared with B-mode ultrasonography alone (k = 0.88 and 0.80 respectively). According to the logistic regression equation obtained, the probability of the presence of endometrioma varied between a minimum of 1.4% for patients with no risk factors to a maximum of 95.6% for patients with two risk factors (CDE result and value of CA125 >25 IU/ml).

A novel method of assessing regurgitant severity: time and spatial integration of cross-sectional color doppler energy images

A novel method of assessing regurgitant severity: time and spatial integration of cross-sectional color doppler energy images

A Novel Method of Assessing Regurgitant Severity: Time and Spatial Integration of Cross-sectional Color Doppler Energy Images

A Novel Method of Assessing Regurgitant Severity: Time and Spatial Integration of Cross-sectional Color Doppler Energy Images

Betamethasone treatment and fetal lung perfusion evaluated with color Doppler energy imaging.

The aim of this study was semiquantitative evaluation of tissue blood flow in the fetal lung before and after administration of betamethasone. This was carried out by means of computer analysis of ultrasound Doppler signals obtained by the color Doppler energy (CDE) technique. CDE signals were recorded in 20 singleton pregnancies with appropriate growth and imminent preterm delivery between 26 and 33 weeks of gestation. The CDE signal recordings were made before and after intramuscular administration of betamethasone 8 mg/day for 3 days. Fixed preset CDE system control settings for the fetal right lung were used during the examinations. Images from CDE scans were recorded on S-VHS videotape and transmitted for computer analysis of 8-bit images at 256 gray-scale levels. The mean flow signal intensity was recorded for the fetal lung before and after betamethasone administration. Additionally, blood velocity waveforms were measured in the intrapulmonary arteries and veins in the peripheral part of the lung. CDE signals from the fetal lung indicated increased energy values after corticosteroid treatment in 16 cases. In three cases there was no change in CDE signal values, and in one case a fall of the signal value was noted. Blood velocity waveforms from the intrapulmonary arteries showed decreased resistance to flow in 15 cases, increased resistance to flow in four cases and no change in one case. No significant differences in venous blood flow velocities were found. In conclusion, the results suggest that there is an increase in fetal lung blood perfusion after maternal corticosteroid administration.

Visualization of the cerebral circulation using three-dimensional transcranial power Doppler ultrasound imaging.

The purpose of this study was to evaluate the anatomy of the cerebral circulation, particularly the circle of Willis, using three-dimensional ultrasound (3DUS) imaging. Image data were obtained through the right transtemporal window from 8 young, healthy volunteers by acquiring gray-scale and color Doppler spectral (CDI) and energy (CDE) images using two-dimensional ultrasound equipment with a 2-MHz probe. Images and transducer position coordinates were fed into a graphics workstation, reprojected, analyzed to extract the blood flow signal, volume rendered, and displayed interactively. The architecture of the cerebral circulation was evaluated from multiple orientations using stereo viewing glasses and rotation to enhance the understanding of vessel position. The primary vessels of the cerebral circulation including the circle of Willis and bilateral views of the branching arteries (middle, anterior, and posterior cerebral arteries and internal carotid artery) could be imaged readily with 3DUS through one transtemporal window. Acquisition time was typically less than 30 seconds. Volume-rendering methods greatly assisted in showing the overall spatial relationships and continuity of cranial vessels. Secondary branches of the cerebral arteries were seen in 2 patients. Color data from two-dimensional ultrasound imaging that otherwise might be identified as artifact was found to represent continuous small vessels on three-dimensional viewing. 3DUS facilitates imaging of cranial vascular anatomy by clarifying overall spatial relationships and enhancing comprehension, compared to two-dimensional ultrasound methods. The method is rapid and the circle of Willis can be visualized from one side of the head.

Use of color Doppler energy in the diagnosis of small hepatocellular carcinoma

Color Doppler energy (CDE) offers a marked improvement in sensitivity over existing color Doppler systems. We report here the use of this system in the diagnosis of small hepatocellular carcinoma (HCC). CDE was used in the clinical investigation of 13 nodules in 12 suspected cases of HCC less than 2 cm in diameter. Findings were compared with those on color Doppler imaging (CDI), angiography, angioechography and histological examination. The apparatus consisted of an Acuson 128XP 10 (ART) with 4- and 5-MHz transducers. Comparison of angiography, angioechography and CDE findings: CDE showed pulsatile flow in 8 of the 9 nodules (88.9%) in which angiography showed tumor stain or angioechography showed positive enhancement. In the 3 nodules in which staining was negative and angioechography showed negative or non-enhancement, CDE showed no pulsatile flow. Comparison between pathological and CDE findings: All 7 nodules which showed moderate or poor differentiation in pathology showed continuous pulsatile flow on CDE. Among 5 well-differentiated HCC, 4 showed no pulsatile flow and 1 showed intermittent pulsatile flow. The remaining non-malignant nodules showed no pulsatile flow. Comparison between CDI and CDE findings: Both CDI and CDE showed pulsatile flow in 8 nodules but with marked differences in sensitivity. Flow was intermittent or spotty with CDI, but mostly showed a continuous branched pattern with CDE. Thus, CDE images correlated well with angiography, angioechography and pathological findings. CDE is an effective and non-invasive means of determining the hemodynamics of small nodules and is useful in the diagnosis of small HCC.