• vessel
  • 4 The velocities measured in each visible vessel were averaged. (bmj.com)
  • Although the ophthalmic artery is the only routinely assessed retrobulbar vessel in CDI which does not enter the eye, its contribution to choroidal blood flow is important. (bmj.com)
  • The purpose was to evaluate the usefulness of this equation in describing the velocity profile and in estimating the volume flow when only one velocity measurement is available near the vessel axis. (biomedsearch.com)
  • An arteriole is a small-diameter blood vessel in the microcirculation that extends and branches out from an artery and leads to capillaries. (wikipedia.org)
  • Since the 1990s many aneurysms are treated by a less invasive procedure called "coiling", which is carried out through a large blood vessel. (wikipedia.org)
  • CBFV
  • An informative response in CBFV was considered to be either (a) a uniphasic, immediate, passive alteration in velocity occurring with the change in posture and without a subsequent change or (b) a biphasic response of an initial change in CBFV followed within 20 seconds by a second response. (bmj.com)
  • atrial
  • The objective of this study was to assess the feasibility and accuracy of magnetic resonance (MR) velocity mapping to calculate pulmonary-to-systemic flow ratio (Qp : Qs) in patients with a suspected or diagnosed atrial-level shunt. (springer.com)
  • MR velocity mapping offers an accurate method to measure aortic and pulmonary artery volume flow that can be useful in the evaluation of atrial-level shunts, in order to establish a definite diagnosis and/or to quantify the Qp : Qs ratio. (springer.com)
  • Quantification of left-to-right atrial shunts with velocity-encoded cine nuclear magnetic resonance imaging. (springer.com)
  • The latter leads to increase risk of atrial fibrillation, which increases the risk of blood stasis (motionless). (wikipedia.org)
  • The result is that the left ventricle gets filled with blood during early ventricular diastole, with only a small portion of extra blood contributed by contraction of the left atrium (the "atrial kick") during late ventricular diastole. (wikipedia.org)
  • Eventually, the left ventricle requires the atrial kick to fill with blood. (wikipedia.org)
  • citation needed] When the mitral valve area goes less than 1 cm2, there will be an increase in the left atrial pressures (required to push blood through the stenotic valve). (wikipedia.org)
  • The loss of the atrial kick due to atrial fibrillation ( i.e. blood cannot flow into the left ventricle thus accumulating in the left atrium ) can cause a precipitous decrease in cardiac output and sudden congestive heart failure. (wikipedia.org)
  • small arterioles
  • A velocity profile equation for blood flow in small arterioles and venules of small mammals in vivo and an evaluation based on literature data. (biomedsearch.com)
  • An empirical parametric equation with 2 bluntness parameters was introduced for describing the velocity profile of blood in the small arterioles and venules of small mammals, in vivo, with the basic approximations of the axisymmetric flow in cylindrical geometry, zero velocity at the wall and a blunter than parabolic flow profile. (biomedsearch.com)
  • measurement
  • Sieverding L, Jung W-I, Klose U, Apirz J. Noninvasive blood flow measurement and quantification of shunt volume by cine magnetic resonance in congenital heart disease. (springer.com)
  • Thrombosis
  • To evaluate the haemodynamic changes induced by flow diversion treatment in cerebral aneurysms, resulting in thrombosis or persisting aneurysm patency over time. (epfl.ch)
  • Relative flow velocity and WSS reduction in and of itself may result in aneurysm thrombosis in the majority of cases. (epfl.ch)
  • Compression stockings are recommended under the following conditions: Tired, aching legs occur when the blood flow slows down in the legs (can be an indicator of deep vein thrombosis). (wikipedia.org)
  • Deep vein thrombosis occurs when blood flow decreases (especially in the lower extremities), causing blood to pool in the legs and leading to blood clot (thrombus) formation. (wikipedia.org)
  • arterioles
  • The muscular contraction of arterioles is targeted by drugs that lower blood pressure (antihypertensives), for example the dihydropyridines (nifedipine and nicardipine), which block the calcium conductance in the muscular layer of the arterioles, causing relaxation. (wikipedia.org)
  • measurements
  • The approach has been thoroughly investigated using both simulations, flow rig measurements, and in-vivo validation against MR scans. (dtu.dk)
  • Measurements of left and right ventricular stroke corresponded closely with those of aortic (r=0.98) and pulmonary flow (r=0.99) respectively, and Qp : Qs flow ratios agreed with stroke volume ratios (r=0.92). (springer.com)
  • Antman EM, Marsh JD, Green LH, Grossman W. Blood oxygen measurements in the assessment of intracardiac left to right shunts: a critical appraisal of methodology. (springer.com)
  • citation needed] In classical mechanics, accurate measurements and predictions of the state of objects can be calculated, such as location and velocity. (wikipedia.org)
  • By 1963, Dr. William Bruce, aware of the tendency of people with coronary artery disease to experience angina (cardiac chest discomfort) during exercise, developed the first standardized method of "stressing" the heart, where serial measurements of changes in blood pressure, heart rate and electrocardiographic (ECG/EKG) changes could be measured under "stress-stress" conditions. (wikipedia.org)
  • estimation
  • This includes synthetic aperture imaging using either spherical or plane waves with velocity estimation performed with directional beamforming or speckle tracking. (dtu.dk)
  • A method for extending the 2D TO method to 3D vector velocity estimation is presented and the implications for future vector velocity imagi- g is indicated. (dtu.dk)
  • haemodynamics
  • Pre- and post-treatment haemodynamics were compared, including mean and maximal velocities, wall-shear stress (WSS) and intra-aneurysmal flow patterns. (epfl.ch)
  • patterns
  • Changes in flow patterns were recorded in only one case. (epfl.ch)
  • One aneurysm remaining patent after 1 year showed no change in flow patterns. (epfl.ch)
  • With a digital signal, it becomes possible to study the patterns of the blood flow moving inside the skull. (wikipedia.org)
  • drainage
  • Changes in cerebral artery blood flow velocity after intermittent cerebrospinal fluid drainage. (bmj.com)
  • Lymphedema occurs when a body part swells due to an abnormal accumulation of lymph fluid, occurring when there is interference with the normal drainage of lymph fluid back into the blood, commonly swelling the arm, leg, neck or abdomen. (wikipedia.org)
  • cardiovascular
  • Analysis of the blood flow velocity in the forearm was made in comparison to established methods of estimating endothelial function, clinical markers of cardiovascular risk, the Framingham risk score and global atherosclerosis determined by whole body magnetic resonance angiography. (diva-portal.org)
  • In conclusion, during reactive hyperemia of the Brachial artery, the systolic to diastolic blood flow velocity ratio appears to contain information of additional value than its components separately, independently of established cardiovascular risk factors. (diva-portal.org)
  • clinical
  • Several clinical examples of complex flow in e.g. bifurcations and around valves have been acquired using a commercial implementation of the method (BK Medical ProFocus Ultraview scanner). (dtu.dk)
  • Magnetic resonance velocity mapping: Clinical application of a new technique. (springer.com)
  • changes
  • Neonatal cerebral blood flow velocity responses to changes in posture. (bmj.com)
  • We conclude that the blood circulation in the uterus and in the dominant ovary changes considerably during the menstrual cycle, whereas that in the non-dominant ovary shows no unequivocal changes. (lu.se)
  • Similar to other neuroimaging techniques such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), fTCD is based on a close coupling between regional cerebral blood flow changes and neural activation. (wikipedia.org)
  • Burtt conducted studies that emphasized the changes in quantitative systolic blood-pressure. (wikipedia.org)
  • Then in 1913 W.M. Marston determined systolic blood-pressure by oscillatory methods and his findings cite definite changes in blood pressure during the deception of criminal suspects. (wikipedia.org)
  • In 1921, John Augustus Larson criticized Marston's intermittent blood pressure method because emotional changes were so brief they could be lost. (wikipedia.org)
  • pressure
  • Increased flow velocity may be associated with a younger age, anemia, severely increased blood pressure, hypermetabolic states such as hyperthyroidism and anemia, increased carbon dioxide tension or some drugs such as an acetazolamid and mannitol. (biomedcentral.com)
  • citation needed] When the mitral valve area goes below 2 cm2, the valve causes an impediment to the flow of blood into the left ventricle, creating a pressure gradient across the mitral valve. (wikipedia.org)
  • When the heart rate goes above a certain point, the diastolic filling period is insufficient to fill the ventricle with blood and pressure builds up in the left atrium, leading to pulmonary congestion. (wikipedia.org)
  • The cortisol levels will rise along with blood pressure. (wikipedia.org)
  • William Moulton Marston studied blood-pressure and noted increase in systolic blood pressure of 10 mm Hg or over indicated guilt through using the tycos sphygmomanometer, with which he reported 90-100% accuracy. (wikipedia.org)
  • To adjust for this he modified the Erlanger sphygmograph to give a continuous blood pressure and pulse curve and used it to study 4,000 criminals. (wikipedia.org)
  • In 1854, he created a device called a sphygmograph, a mechanism consisting of weights and levers used to estimate blood pressure, and considered to be a forerunner of the modern sphygmomanometer. (wikipedia.org)
  • Medications such as labetalol may be required to lower the blood pressure until repair can occur. (wikipedia.org)
  • Circulation
  • Knee-high compression stockings are used not only to help increase circulation, but also to help prevent the formation of blood clots in the lower legs. (wikipedia.org)
  • Vierordt developed techniques and tools for the monitoring of blood circulation. (wikipedia.org)
  • Stroke
  • Qp : Qs ratios were calculated from both stroke volume data and flow data. (springer.com)
  • Battery-powered, it would use an RF link to a portable computer running a spectral analysis routine together with input from an oximeter (monitoring the degree of blood oxygenation, which a stroke might impair) to make the automatic decision to administer the drug. (wikipedia.org)
  • peripheral
  • Chronic peripheral venous insufficiency is when the veins cannot pump deoxygenated blood back to the heart. (wikipedia.org)
  • Any pathology which constricts blood flow, such as stenosis, will increase total peripheral resistance and lead to hypertension. (wikipedia.org)