The role of sympathetic innervation in the control of spontaneous fluctuations of cerebral blood flow is still poorly understood. In conscious, unrestrained rats, blood flow velocity (pulsed Doppler) was measured in both internal carotid arteries one week after either excision of the right superior cervical ganglion (n = 8) or ...

OBJECTIVE: To investigate the effectiveness of a single pre-operative dose of sublingual misoprostol on reducing blood loss in abdominal hysterectomies performed for symptomatic uterine leiomyomas. STUDY DESIGN: A cohort of 64 women undergoing total abdominal hysterectomy for symptomatic uterine leiomyomas were randomly assigned to receive a single dose of sublingual ...

Patent ductus arteriosus is a common occurrence among prematurely born neonates and is believed to play a role in the development of other complications of prematurity including intraventricular hemorrhage, bronchopulmonary dysplasia, and necrotizing enterocolitis. The clinical decision to treat the patent ductus arteriosus is complicated by the lack of evidence ...

Aims:  The aim of this study was to compare the effectiveness and safety of sublingual misoprostol with i.v. oxytocin infusion administered after delivery in reducing blood loss at cesarean section in Nigeria. Materials and Methods:  One hundred women with term singleton pregnancy undergoing elective or emergency cesarean section under spinal ...

The treatment of burns remains a challenge. Besides the administration of physiological saline, local disinfection and symptomatic medications, no causal therapy is known to accelerate angiogenesis and wound healing. The aim of this study was to investigate the influences of dilatative and anti-inflammatory acting drugs on microcirculation, angiogenesis and leukocyte ...

A 3-month-old girl presented with total urinary incontinence along with small bladder and bilateral single-system vaginal ectopic ureters [BSSVEU]. Bladder augmentation was done with dilated ureters (ureterocystoplasty) based on proximal blood supply of the ureters.

OBJECTIVE:: The purpose of this study was to evaluate whether the use of oxytocin during the first and second stages of labor is associated with a higher incidence of postpartum hemorrhage (PPH) in pregnant women who received active management of third stage of labor (AMTSL). STUDY DESIGN:: A secondary data ...

Patent ductus arteriosus in extremely premature babies is associated with major neonatal morbidities such as necrotizing enterocolitis and intraventricular haemorrhage. Altered systemic blood flow and end-organ hypoperfusion are known associates of a haemodynamically significant ductus arteriosus where descending aorta blood flow profiles may reveal abnormal diastolic retrograde flow. A preterm ...

Development of retrograde blood flow may be observed in the vertebral artery and is associated with progressive ipsilateral proximal subclavian or innominate artery stenosis. The subclavian steal phenomenon is more prevalent in the left subclavian artery (LSA). The purpose of this study was to analyze the correlation between the degree ...

Three-dimensional (3D) Doppler quantification within the uteroplacental unit could be of great help in understanding and screening for pre-eclampsia and intrauterine growth restriction. Yet the correlation between 3D Doppler indices and true blood flow has not been confirmed in vivo. The aim of this study was to evaluate this correlation ...

To determine the pulpal blood flow (PBF) changes in anchorage teeth associated with the high forces of a rapid maxillary expansion (RME) appliance. The study was performed with 14 girls and 7 boys for a total of 21 patients between 10 and 15 years of age (mean, 13.1 +/- 1.39 ...

The resistive index (RI) is a functional hemodynamic index used to measure flow resistance within an organ, such as the kidney, to assess if there is any vascular disease associated with that organ. Currently, the measurement of RI values using spectral Doppler ultrasound (US) is performed in one location at ...

We read with great interest the recent article by Dr. Carotti and colleagues regarding the detection of abnormal vascularization in inflammatory joints of rheumatoid arthritis patients. We do, however, be very doubtful about the results. In the colour flow signals of joint of rheumatoid arthritis patient, the resistive index cannot ...

Hypoxia and decreased blood supply have been proposed as risks for tendon rupture. Visualization of the vascularity of intact and torn rotator cuffs would be useful for improving treatments for rotator cuff tear. To assess vascularity inside a tendon or an adjacent rotator cuff insertion point in patients differing in ...

Learning the principles and application of Doppler ultrasound is difficult and requires repeated practice. Flow phantoms provide a method of teaching Doppler techniques before their application in clinical patients; however, commercially available flow phantoms are expensive. Herein we describe an easily constructed, economic Doppler flow phantom, utilizing readily available products, ...

This article describes the technique of continuous laser Doppler flowmetry (LDF) as applied to the measurement of the flux of red blood cells in the optic nerve head, iris and subfoveal choroid. Starting with the exposition of the physical principles underlying LDF, we first describe the various devices developed to ...

Enhancing the performance of clarifiers requires a thorough understanding of their hydraulics. Fluorescence spectroscopy and acoustic doppler velocimeter (ADV) profiling generally have been used separately to evaluate secondary settlers. We propose that simultaneous use of these techniques is needed to obtain a more reliable and useful evaluation. Experiments were performed ...

Tendon-related injuries are a major problem, but the aetiology of tendinopathies is unknown. In tendinopathies as well as during unaccustomed loading, intra-tendinous flow can be detected indicating that extensive loading can provoke intra-tendinous flow. The aim of present study is to evaluate the vascular response as indicated by colour Doppler ...

New detection methods for vascular injuries can augment the usability of an ultrasound (US) imager in trauma settings. The goal of this study was to evaluate a potential-detection strategy for internal bleeding that employs a well-established theoretical biofluid model, the power law. This law characterizes normal blood-flow rates through an ...

Doppler ultrasound is routinely used in the clinical setting to evaluate blood flow in many major vessels of the body. Spectral Doppler is used to display the normal and abnormal signature waveforms that are unique to each vessel. It is important for the sonographer and the radiologist to recognize both ...

We propose spectral domain Doppler optical coherence tomography (SD-D-OCT) to qualitatively measure red blood cell aggregation. Variance/standard deviation (SD) of the Doppler frequency spectrum in Doppler variance imaging of flowing blood under shearing conditions was developed as a new aggregation index. In in vitro microchannel-flow experiments, porcine blood at various ...

Transvaginal ultrasound-guided oocyte retrieval has gained universal acceptance with an excellent safety record overall. However, even with contemporary ultrasound resolution, the aspiration needle can injure adjacent pelvic organs and blood vessels and result in external and internal bleeding. Although the idea that Doppler ultrasound might reduce the risk of blood ...

The purpose was to describe blood flow waveform of pelvic organs obtained by Doppler according to their unique characteristics. A prospective study was designed and 79 premenopausal and postmenopausal women were screened. Transvaginal ultrasonography combined with color Doppler was performed. Arterial blood flow of the uterus, fallopian tubes and both ...

New ultrasound techniques for blood flow estimation have been investigated in-vivo. These are vector velocity estimators (Transverse Oscillation, Synthetic Transmit Aperture, Directional Beamforming and Plane Wave Excitation) and adaptive spectral estimators (Blood spectral Power Capon and Blood Amplitude and Phase Estimation). It was shown that the vector velocity estimators can ...

A method is proposed to measure transverse blood flow by using photoacoustic Doppler broadening of bandwidth. By measuring bovine blood flowing through a plastic tube, the linear dependence of the broadening on the flow speed was validated. The blood flow of the microvasculature in a mouse ear and a chicken ...

Three-dimensional echocardiography of colour Doppler flow developed quickly with the advent of three-dimensional echocardiography. An increasing amount of research has shown that three-dimensional echocardiography of colour Doppler flow is feasible and facilitates measurement of stroke volume and cardiac output, and assessment of heart valve and congenital heart diseases. Although the ...

According to a study conducted on a population of 9,248 subjects, cardiac diseases are the second most prevalent cause of death in the dog. During the last decades, a common scenario has been the increase on life expectancy of dogs. The exact relationship between the negative modifications of cardiovascular function ...

The authors propose a new sensor structure for an integrated laser Doppler blood flowmeter that consists of two silicon cavities with a PD and laser diode inside each cavity. A silicon lid formed with a converging microlens completes the package. This structure, which was achieved using micromachining techniques, features reduced ...

Vortex shedding due to flow past a cylindrical object and its accompanying sound are well-described phenomena, though research has often focused on the sound broadcast in directions transverse to the wire and downstream in high-speed flows. Here, we investigate the sound broadcast in angles nearly opposite the direction of low-speed ...

BACKGROUND: Many implantable ventricular assist devices (VADs) have no direct measurement of pump output. The aim of this study was to test the hypothesis that quantitative contrast echocardiography can be used to measure VAD output. METHODS: Contrast-enhanced Doppler velocity-time integral (VTI) was measured in the VAD inlet and outlet cannulae. ...

We propose a new method to measure transverse flow velocity based on photoacoustic Doppler bandwidth broadening, which is determined by the geometry of the probe-beam and the velocity of the transverse flow. By exploiting pulsed laser excitation and raster motor scanning, three-dimensional structure and flow velocity can be imaged simultaneously. ...

OBJECTIVES: To evaluate the presence of false flow three-dimensional (3D) power Doppler signals in 'flow-free' models. METHODS: 3D power Doppler datasets were acquired from three different flow-free phantoms (muscle, air and water) with two different transducers and Virtual Organ Computer-aided AnaLysis was used to generate a sphere that was serially ...

INTRODUCTION: This study compared the difference in pulpal blood flow between vital and root-filled teeth by using ultrasound Doppler imaging. METHODS: To compare the difference in pulpal blood flow between vital and root-filled teeth, 11 patients (mean age, 32.06 years; 3 male, 8 female) who had undergone root canal treatment ...

In this paper a novel technique for flow measurement which is based on the photoacoustic (PA) Doppler effect is described. A significant feature of the proposed approach is that it can be implemented using tone burst optical excitation thus enabling simultaneous measurement of both velocity and position. The technique, which ...

We describe the transcranial Doppler pattern during a period of cardiopulmonary resuscitation in a patient undergoing a transcatheter off-pump aortic valve implantation. Transcranial Doppler of the middle cerebral artery flow was measured as a part of a separate ongoing study. The patient developed a cardiac arrest during deployment of the ...

OBJECTIVES: To evaluate the presence of blood flow by colour Doppler ultrasonography (CDUS) in the wrist and finger joints of rheumatoid arthritis (RA) patients and healthy subjects and to define a cut-off value of CDUS resistive index (RI). METHODS: Forty-three patients with RA and 43 healthy controls were examined by ...

Two-dimensional angle-independent blood velocity estimates typically combine the Doppler frequencies independently measured by two ultrasound beams with known interbeam angle. A different dual-beam approach was recently introduced in which one (reference) beam is used to identify the flow direction, and the second (measuring) beam directly estimates the true flow velocity ...

The aim of this study was to validate a non-invasive optical probe for simultaneous blood flow measurement at different vascular depths combining three photoplethysmography (PPG) channels and laser Doppler flowmeter (LDF). Wavelengths of the PPG were near-infrared 810 nm with source-to-detector separation of 10 and 25 mm, and green 560 ...

A thorough preoperative vascular evaluation should be performed before the initiation of any lower extremity surgical intervention, but particularly in situations of diabetic foot reconstruction with compromised blood flow. The intended emphasis of this brief report is to provide the foot and ankle surgeon with an appreciation for the clinical ...

Transcranial Doppler ultrasonography (TCD) is the only non-invasive examination that provides a reliable evaluation of intracranial blood flow patterns in real-time, adding physiological information to the anatomical information obtained from other neuroimaging modalities. TCD is relatively cheap, can be performed bedside, and allows monitoring both in acute emergency settings as ...

In recent years, chemistry in flowing systems has become more prominent as a method of carrying out chemical transformations, ranging in scale from microchemistry up to kilogram-scale processes. Compared to classic batch ultrasound reactors, flow reactors stand out for their greater efficiency and flexibility as well as lower energy consumption. ...

Visualization of cavitation behavior in a rectangular sonochemical reactor at 490 kHz was carried out by a laser sheet technique and the distribution of liquid flow was measured by a laser Doppler velocimeter. The pattern of liquid flow and distribution of acoustic pressure of the rectangular sonochemical reactor were investigated ...

Pseudopterosins extracted from Caribbean Sea Whip (Pseudopterogorgia elisabethae) were previously shown to inhibit phospholipase A2, an enzyme that functions in the arachidonic acid cascade of inflammation. With an objective to test its in vivo anti-inflammatory potential, we conducted a screening clinical bioassay using randomized analysis on sixteen panelists. An emulsion ...

OBJECTIVE: Volumetric flow measurement with Doppler ultrasound is useful in assessing blood flow as part of an evaluation of arteriovenous fistula maturity in patients undergoing hemodialysis. In this study, we assessed both accuracy and variability in volumetric flow measurements obtained using modern and commercially available ultrasound systems and an in ...

An abnormal level of red blood cell (RBC) aggregation is a clinical condition associated with many pathologies. Our purpose is to investigate the feasibility of spectral domain phase-resolved optical Doppler tomography incorporated with Doppler variance imaging to characterize RBC aggregation in flowing blood. Variance/standard deviation (SD) of the Doppler frequency ...

Monitoring of aortic blood flow, conducting large portions of the cardiac output (CO), allows conclusions on the global hemodynamic status of patients. For this purpose, transesophageal Doppler (TED) devices have been developed, which interrogate the descending aorta and calculate aortic blood flow velocity using the Doppler principle. The recorded velocity-time ...

Changes in blood flow to the inner ear are thought to influence a number of cochlear diseases, including noise-induced hearing loss, sudden hearing loss, and Meniere's disease. Advances have been made in the areas of vital microscopic studies of micro-circulation, and the laser Doppler flowmetry. But none of these techniques ...

To verify a previously reported three-dimensional (3D) ultrasound method for the measurement of time-average volumetric blood flow, experiments were performed under pulsatile flow conditions, including in vivo investigations, and results were compared with accepted, but invasive, "gold standard" techniques. Results showed that volume averaging results in the correct time-average volume ...

Accurate noninvasive quantification of volume blood flow in the uterine arteries (UtAs) would have clinical and research benefits. We evaluated the correlation and agreement between uterine artery volume blood flow (UtABF) as calculated (cUtABF) from color/pulsed-wave Doppler acquisitions and that measured (mUtABF) by bilateral perivascular transit-time flow probes in 6 ...

Ultrasound Doppler using two-dimensional (2D) techniques is commonly used to study blood flow and myocardial tissue motion. This use includes measurement of velocity and time intervals, often in relation to the electrocardiogram (ECG) signal. 2D Doppler is frequently considered a real-time technique but in reality the acquisition time can be ...