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This review pays tribute to those pioneers in Doppler flow during an early and exciting period ranging from the end of the 1960s to the 1990s. Three major 'approaches' contributed to what is nowadays built into every patient's inv...
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This review pays tribute to those pioneers in Doppler flow during an early and exciting period ranging from the end of the 1960s to the 1990s. Three major 'approaches' contributed to what is nowadays built into every patient's investigation. The source was Daniel Kalmanson, who developed flow directionality, assigning a physiological meaning to the recordings. This was the first time Doppler flow was used on the heart, providing new insights in cardiac pathophysiology. The second approach relied on the Norwegian group who applied the laws of physics to fluid dynamics. Simplification of the formula provided a new non-invasive approach enabling quantification of valvular lesions and haemodynamic measurements. This new tool pushed back previous routine catheterisation. To crown it all, the introduction of colour Doppler flow, mainly relying on the Japanese groups, overcame the long-lasting scepticism of the scientific community: cardiologists started to 'believe' in the Doppler technique. Other innovative pioneers around the world joined the three groups to develop this new field of cardiology. At the turning of the new millennium, the Doppler technique is mature, through a strong methodology. Convergence of the three original approaches for mutual benefit, constant update of examination modalities according to improved technology, and new insights into cardiac dynamics, are the three cornerstones supporting this methodology. They should contribute to keep it alive and efficient, independently of the imaging modality of the future.
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We evaluated the usefulness of real-time colour Doppler flow (CDF) endoscopic ultrasonography (EUS) for differentiating neoplastic gallbladder (GB) polyps from non-neoplastic polyps.
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The aim of the study was to evaluate the influence of sildenafil citrate administrated intravaginaly on the blood flow in the bovine uterus during dioestrus. Uterine blood flow was examined in six healthy adult cows. Sildenafill a...
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The aim of the study was to evaluate the influence of sildenafil citrate administrated intravaginaly on the blood flow in the bovine uterus during dioestrus. Uterine blood flow was examined in six healthy adult cows. Sildenafill as administrated intravaginaly to each cow between the 6th and 8th d of the ovarian cycle, in the form of vaginal suppositories containing 100 mg of active substance at a dose of 100, 200, or 300 mg per animal. Uterine perfusion was estimated by the colour Doppler examination, and obtained results were analysed with the Pixel Flux Software (Chameleon, Germany). Morecover. cardiovascular parameters were also evaluated. Animals were examined before and five times after drug application two times at 15 min intervals, and three times at 2 h intervals). A placebo suppository was also given to the cows. The analysis of the intensity and velocity of blood flow in the uterus proved that sildenafil administrated intravaginaly significantly increased blood Ilm\ in the uterus and the effect of increased perfusion was observed for 4 h and 30 min after administration. The effect of increased uterine perfusion was observed after low as well as high doses of sildenafil. Significant changes in the cardio- vascular parameters were not detected. There were no changes in the uterine perfusion as well as in cardiovascular parameters after placebo administration.
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Colour flow imaging (CFI) is an ultrasound imaging technique whereby colour-coded maps of tissue velocity are superimposed on grey-scale pulse-echo images of tissue anatomy. The most widespread use of the method is to image the mo...
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Colour flow imaging (CFI) is an ultrasound imaging technique whereby colour-coded maps of tissue velocity are superimposed on grey-scale pulse-echo images of tissue anatomy. The most widespread use of the method is to image the movement of blood through arteries and veins, but it may also be used to image the motion of solid tissue. The production of velocity information is technically more demanding than the production of the anatomical information, partly because the target of interest is often blood, which backscatters significantly less power than solid tissues, and partly because several transmit-receive cycles are necessary for each velocity estimate. This review first describes the various components of basic CFI systems necessary to generate the velocity information and to combine it with anatomical information. It then describes a number of variations on the basic autocorrelation technique, including cross-correlation-based techniques, power Doppler, Doppler tissue imaging, and three-dimensional (3D) Doppler imaging. Finally, a number of limitations of current techniques and some potential solutions are reviewed.
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PurposePrevious reports showed increased flow velocities in retrobulbar vessels after glaucoma surgery in the first weeks. Colour Doppler imaging was performed to investigate the long-term effects of trabeculectomy on retrobulbar ...
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PurposePrevious reports showed increased flow velocities in retrobulbar vessels after glaucoma surgery in the first weeks. Colour Doppler imaging was performed to investigate the long-term effects of trabeculectomy on retrobulbar haemodynamics in patients with primary open-angle glaucoma (POAG).
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Colour-flow Doppler sonography has been described as a means of assessing corpus luteum (CL) function rapidly, because area of luteal blood vessels correlates well with circulating progesterone (P-4) concentrations [P-4] in oestro...
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Colour-flow Doppler sonography has been described as a means of assessing corpus luteum (CL) function rapidly, because area of luteal blood vessels correlates well with circulating progesterone (P-4) concentrations [P-4] in oestrous cycling mares. The aim of this study was to assess the relationships between CL size and vascularity, and circulating [P-4] during early pregnancy in mares, and to determine whether luteal blood flow was a useful aid for selecting an embryo transfer recipient. Equine embryos (n = 48) were recovered 8 days after ovulation and were transferred to available recipient mares as part of a commercial program with the degree of synchrony in timing of recipient ovulation ranging from 1 day before to 4 days after the donor. Immediately prior to embryo transfer (ET), maximum CL cross-section and blood vessel areas were assessed sonographically, and jugular blood was collected to measure plasma [P-4]. Sonographic measurements and jugular blood collection were repeated at day 4 after ET for all mares, and again at days 11, 18 and 25 after ET in mares that were pregnant. The number of grey-scale and colour pixels within the CL was subsequently quantified using Image) software. The CL blood flow correlated significantly but weakly with plasma [P-4] on the day of transfer and on day 4 after ET in all mares, and on days 11 and 25 after ET in pregnant mares (r=0.30-0.36). The CL area and plasma [P-4] were also correlated on each day until day 11 after ET (r=0.49-0.60). The CL colour pixel area decreased significantly after day 18, whereas CL area was already decreasing by day 4 after ET. The CL area, area of blood flow, or [P-4] was predictive of pregnancy. Findings in the present study suggest that both CL area and blood flow are correlated with circulating [P-4] at the time of transfer and in early pregnancy. Evaluation of the CL using B-mode or CF sonography, although practical, provides no improvement in the selection of recipients or prediction of pregnancy outcomes than methods employed currently. (C) 2016 Elsevier B.V. All rights reserved.
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Introduction The advances in research methods used in ophthalmology allow for an increasingly accurate examination of the eyes, as well as the morphology and function of the vessels. Colour Doppler imaging is still the first-line ...
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Introduction The advances in research methods used in ophthalmology allow for an increasingly accurate examination of the eyes, as well as the morphology and function of the vessels. Colour Doppler imaging is still the first-line method for the analysis of parameters of retrobulbar circulation. Therefore, the aim of this work was to present the current state of knowledge about anatomical and functional age-related changes in retrobulbar arteries. Methods A literature search was performed mainly based on the PubMed database. Results The anatomy of retrobulbar arteries, histological background of age-related vascular changes, age-related changes in retrobulbar blood flow in the ophthalmic artery, central retinal artery, short posterior ciliary arteries, and the reference values for the age-dependent retrobulbar circulation parameters measured by colour Doppler imaging are discussed in this review. Conclusion The age of the subject should always be taken into account when interpreting the parameters of retrobulbar blood flow measured by colour Doppler imaging.
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The aim of this study was to investigate the useililness of new software Pixel Flux (PXFX) for clinical evaluation of tissue perllision in the field of reproduction in dogs. The experiment was performed on six adult Beagle dogs. D...
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The aim of this study was to investigate the useililness of new software Pixel Flux (PXFX) for clinical evaluation of tissue perllision in the field of reproduction in dogs. The experiment was performed on six adult Beagle dogs. Different organs and tissues of the animals were examined with the MyLab25 Gold ultrasound system. Blood flow in the ovary, testicle, prostate, the ramification of the penile artery, and the network of blood vessels of the pampiniform plexus were examined with the use of colour coded Doppler technique, and obtained data was evaluated with the PXFX software. The more objective digital evaluation of data obtained with colour Doppler sonography through the application of dynamic tissue perfusion measurements provides new opportunities for diagnosis, as well as continuous monitoring of the function of the examined tissues and organs. The use of PXFX software is strongly indicated as a tool in small animal practice as an additional method for evaluation of tissue perfiision, especially in the cases when other methods like pulsed wave Doppler techniques are ditficult to be performed.
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Background & Aims Myofascial pain syndrome (MPS) is a common non-articular disorder of the musculoskeletal system that is characterized by the presence of myofascial trigger points (MTrPs). Despite the high prevalence of MPS, its pathogenesis, which induces the onset and maintenance of MTrPs, is still not completely understood. To date, no studies have investigated the changes in the biochemical milieu caused by ischaemia/hypoxia in the MTrP regions of muscle that are proposed in the integrated hypothesis. Therefore, this study investigated whether ischaemic/hypoxic conditions participate in the formation of active MTrPs and affect angiogenesis using colour Doppler flow imaging (CDFI). Methods Twenty-five Sprague-Dawley rats were randomly divided into a model group and a normal control group. A model of active MTrPs was established by a blunt strike combined with eccentric exercise. Enzyme-linked immunosorbent assays (ELISAs) were employed to detect the levels of HIF-1α and VEGF. Microvessel density (MVD) was evaluated using immunohistochemistry. CDFI was applied to observe the blood flow signals in the MTrPs, which were classified into four grades based on their strengths. Results Compared with the control group, the active MTrP group exhibited significantly higher HIF-1α and VEGF levels and MVD values. These differences were accompanied by increased blood flow signals. In the active MTrP group, the blood flow signal grade was positively correlated with the MVD (P?<?0.05) and independently correlated with the VEGF level (P?<?0.05) but was not correlated with the expression of HIF-1α (P?0.05). Conclusion Ischaemic/hypoxic conditions may be involved in the formation of MTrPs. CDFI...
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Background & Aims Myofascial pain syndrome (MPS) is a common non-articular disorder of the musculoskeletal system that is characterized by the presence of myofascial trigger points (MTrPs). Despite the high prevalence of MPS, its pathogenesis, which induces the onset and maintenance of MTrPs, is still not completely understood. To date, no studies have investigated the changes in the biochemical milieu caused by ischaemia/hypoxia in the MTrP regions of muscle that are proposed in the integrated hypothesis. Therefore, this study investigated whether ischaemic/hypoxic conditions participate in the formation of active MTrPs and affect angiogenesis using colour Doppler flow imaging (CDFI). Methods Twenty-five Sprague-Dawley rats were randomly divided into a model group and a normal control group. A model of active MTrPs was established by a blunt strike combined with eccentric exercise. Enzyme-linked immunosorbent assays (ELISAs) were employed to detect the levels of HIF-1α and VEGF. Microvessel density (MVD) was evaluated using immunohistochemistry. CDFI was applied to observe the blood flow signals in the MTrPs, which were classified into four grades based on their strengths. Results Compared with the control group, the active MTrP group exhibited significantly higher HIF-1α and VEGF levels and MVD values. These differences were accompanied by increased blood flow signals. In the active MTrP group, the blood flow signal grade was positively correlated with the MVD (P?<?0.05) and independently correlated with the VEGF level (P?<?0.05) but was not correlated with the expression of HIF-1α (P?0.05). Conclusion Ischaemic/hypoxic conditions may be involved in the formation of MTrPs. CDFI is useful for detection of the features of angiogenesis in or surrounding MTrPs via assessment of blood flow signals.
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We present a new method for reconstructing a 3D + t velocity field from multiple 3D + t colour Doppler images. Our technique reconstructs 3D velocity vectors from registered multiple standard 3D colour Doppler views, each of which...
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We present a new method for reconstructing a 3D + t velocity field from multiple 3D + t colour Doppler images. Our technique reconstructs 3D velocity vectors from registered multiple standard 3D colour Doppler views, each of which contains a 1D projection of the blood velocity. Reconstruction is based on a scalable patch-wise Least Mean Squares approach, and a continuous velocity field is achieved by using a B-spline grid. We carry out a sensitivity analysis of clinically relevant parameters which affect the accuracy of the reconstruction, including the impact of noise, view angles and registration errors, using simulated data. A realistic simulation framework is achieved by a novel noise model to represent variations in colour Doppler images based on multiscale additive Gaussian noise. Simulations show that, if the Target Registration Error < 2.5mm, view angles are > 20° and the standard deviation of noise in the input data is < 10cm/s, the reconstructed velocity field presents visually plausible flow patterns and mean error in flow rate is approximately 10% compared to 2D + t Flow MRI. These results are verified by reconstructing 3D velocity on three healthy volunteers. The technique is applied to reconstruct 3D flow on three paediatric patients showing promising results for clinical application.
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