Search results for "Blood Flow Velocity"
showing 10 items of 132 documents
Clinical-anamnestic and instrumental data in outpatients suffering from venous disease
1995
The authors studied 200 consecutive outpatients with symptoms due to venous disease of the lower limbs. All the patients underwent anamnestic, clinical and instrumental evaluation (c.w. Doppler velocimetry and strain-gauge plethysmography). The results of this study showed that some anamnestic and clinical data are significantly related to venous disease detected by instrumental techniques. The superficial and deep vein hypertension were, instead, correlated to oral contraceptive use.
Ticlopidine in the Treatment of Multiple Atherosclerotic Arteriopathy: a Strain Gauge Plethysmography and Döppler Spectrum Analysis Evaluation
1987
The effect of ticlopidine was compared with flunarizine in patients with iliac–femoral and / or femoral–popliteal arteriosclerotic arteriopathy accompanied by lesions of the cervical arteries of no haemodynamic significance. In the lower limbs, plethysmography (strain gauge measurements) and Döppler ultrasonography integrated by spectral analysis of the cervical arteries showed qualitative and quantitative improvements of the regional haematic flow. Side-effects were negligible which suggests that ticlopidine is useful in the treatment of multiple arteriosclerotic arteriopathy.
Dynamic cerebrovascular autoregulation in patients prone to postural syncope: Comparison of techniques assessing the autoregulation index from sponta…
2021
Abstract Three approaches to the assessment of cerebrovascular autoregulation (CA) via the computation of the autoregulation index (ARI) from spontaneous variability of mean arterial pressure (MAP) and mean cerebral blood flow velocity (MCBFV) were applied: 1) a time domain method (TDM); 2) a nonparametric method (nonPM); 3) a parametric method (PM). Performances were tested over matched and surrogate unmatched pairs. Data were analyzed at supine resting (REST) and during the early phase of 60° head-up tilt (TILT) in 13 subjects with previous history of postural syncope (SYNC, age: 28 ± 9 yrs.; 5 males) and 13 control individuals (noSYNC, age: 27 ± 8 yrs.; 5 males). Analysis was completed b…
Sympathetic Vasomotor Response of the Radial Artery in Patients With Diabetic Foot Syndrome
2003
OBJECTIVE—Neurophysiological assessment of the peripheral autonomic system is characterized by various limitations. An alternative approach to laser Doppler and venous plethymography is the assessment of the sympathetic vasomotor response of the radial artery obtained by continuous wave Doppler sonography. Nomogram data have been established and demonstrate the temporary disappearance of diastolic flow after coughing or deep inspiration. RESEARCH DESIGN AND METHODS—We assessed the sympathetic vasomotor response in 25 patients (mean age 64 years, range 43–76) with diabetic foot syndrome. The Doppler data were correlated with nerve conduction studies of the median and peroneal nerve, the exte…
Changes in the cerebrovascular effects of endothelin-1 and nicardipine after experimental subarachnoid hemorrhage.
1993
The role of endothelium-related factors in the pathogenesis of cerebral vasospasm after subarachnoid hemorrhage (SAH) has gained interest since the discovery of endothelin-1 (ET-1). We have examined, before and after SAH, the responsiveness of the cerebrovascular bed of the goat to ET-1, the sources of Ca2+ in ET-1-induced responses, and the ability of the Ca2+ entry blocker nicardipine to counteract them. Before SAH, injection of ET-1 into the cerebral circulation increased cerebrovascular resistance, thereby producing dose-dependent reductions in cerebral blood flow (CBF), which were prevented by nicardipine. In isolated middle cerebral arteries, ET-1 induced concentration-dependent contr…
Deep vein thrombus formation induced by flow reduction in mice is determined by venous side branches.
2013
Interaction between vascular wall abnormalities, inflammatory leukocytes, platelets, coagulation factors and hemorheology in the pathogenesis of deep vein thrombosis (DVT) is incompletely understood, requiring well defined animal models of human disease. METHODS AND RESULTS: We subjected male C57BL/6 mice to ligation of the inferior vena cava (IVC) as a flow reduction model to induce DVT. Thrombus size and weight were analyzed macroscopically and sonographically by B-mode, pulse wave (pw) Doppler and power Doppler imaging (PDI) using high frequency ultrasound. Thrombus size varied substantially between individual procedures and mice, irrespective of the flow reduction achieved by the ligatu…
The Long-Term Effect of Sevoflurane on Neuronal Cell Damage and Expression of Apoptotic Factors After Cerebral Ischemia and Reperfusion in Rats
2006
We investigated the long-term effects of sevoflurane on histopathologic injury and key proteins of apoptosis in a rat hemispheric ischemia/reperfusion model. Sixty-four male Sprague-Dawley rats were randomly assigned to Group 1 (fentanyl and N2O/O2; control) and Group 2 (2.0 vol% sevoflurane and O2/air). Ischemia (45 min) was produced by unilateral common carotid artery occlusion plus hemorrhagic hypotension (mean arterial blood pressure 40 mm Hg). Animals were killed after 1, 3, 7, and 28 days. In hematoxylin and eosin-stained brain sections eosinophilic hippocampal neurons were counted. Activated caspase-3 and the apoptosis-regulating proteins Bax, Bcl-2, Mdm-2, and p53 were analyzed by i…
Umbilical artery blood flow velocity waveforms during variable decelerations of the fetal heart rate
1991
Blood flow velocities of the umbilical arteries were measured by Doppler ultrasonography during variable decelerations of the fetal heart rate. The flow velocity waveforms, being normal between uterine contractions, showed either an unchanged flow velocity waveform with an exclusive fetal heart rate effect on end-diastolic velocities or a rapid change to absent and reverse diastolic flow during the decelerations, indicating an abrupt increase in placental resistance with a halt in placental perfusion. Computer-aided reconstruction of the fetal heart rate curve revealed the exact temporal relationship between the reduction of umbilical artery perfusion and deceleration of fetal heart rate. W…
Changes in microregional perfusion, oxygenation, ATP and lactate distribution in subcutaneous rat tumours upon water-filtered IR-A hyperthermia
1995
The effect of hyperthermia on microcirculatory and metabolic parameters in s.c. DS-sarcomas of different sizes on the hind foot dorsum of SD-rats was investigated. Hyperthermia was carried out using a novel water-filtered, infrared-A radiation technique. Heating was performed at a rate of 0.5 degrees C/min until 44 degrees C was achieved in the tumour centre, which was maintained for 60 min. Using a multichannel laser Doppler flowmeter, red blood cell flux could be assessed continuously and at several sites within the tumour tissue simultaneously. Substantial inter-site variations in laser Doppler flux (LDF) were observed during hyperthermia which were independent of tumour size, site of me…
Automatic or manual arterial path for the ankle-brachial differences pulse wave velocity
2018
Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0206434 An automated method for measuring arterial path length with devices that determine pulse wave velocity (PWV) in peripheral arteries is frequently applied. We aimed to compare arterial path length measurements based on mathematical height-based formulas with those measured manually and to assess whether the ankle-brachial difference (abD-PWV) measured with the VOPITB device is comparable to that obtained by manual measurements. In 245 patients, a metric measuring tape was used to determine the arterial path length from the suprast…