589 results about "Blood flow volume" patented technology

A method of increasing blood flow through an obstructed blood vessel includes providing an expandable member substantially made of a mesh having a plurality of interstices. The expandable member has a proximal member end and a distal member end spaced longitudinally apart by a tubular member body. The expandable member is substantially closed at the distal member end. The expandable member is inserted into the blood vessel. The expandable member is positioned within the blood vessel with the proximal member end upstream of the distal member end and the member body located radially adjacent at least a portion of an obstruction. The expandable member is expanded to bring at least a portion of the member body into contact with the obstruction. An outward radial force is exerted on the obstruction to dislodge at least one fragment from the obstruction and to enhance blood flow through the blood vessel past the obstruction. The at least one fragment is passed through at least one interstice of the member body in the radial direction. The at least one fragment is selectively retained within the expandable member. An apparatus for increasing blood flow through an obstructed blood vessel is also provided.

Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data.

An electronic monitoring device includes an electronic processor (520) having at least one signal input for body monitoring, and a memory (530) holding instructions for the electronic processor coupled to the electronic processor so that the electronic processor is operable to isolate a cardiac signal including cardiac pulses combined with other cardiac signal variations, and the electronic processor further operable to execute a filter (730) that separates a varying blood flow signal from the cardiac pulses and to output information (790) based on at least the varying blood flow signal. Other devices, sensor assemblies, electronic circuit units, and processes are also disclosed.

Blood sugar levels are measured non-invasively based on temperature measurement. Values of blood sugar levels non-invasively measured by a temperature measuring system are corrected using blood oxygen saturation and blood flow volume. Optical sensors are provided for detecting scattered light, reflected light, and light that enters into the skin which travels out of the body surface. The measurement data is stabilized by taking into consideration the influence of the thickness of skin on blood oxygen saturation.

Luminal endoprosthesis formed of a multi-layer braided framework. The framework is devoid of any cover layer, and formed of a plurality of stabilized layers of biocompatible metal wires which are interlaced, forming a lattice, a plurality of wires of a given layer being integrated in the lattice of the adjacent layers. The mechanical characteristics of an outermost layer is so that when in place, the layer applies against a vessel wall, the other layers extending substantially along cylindrical surfaces distinct from the outermost layer so as to form a multi-layer mat which affects the haemodynamic of a flow of blood passing along or through this mat and preventing a growing of plaque.

Blood sugar levels are non-invasively measured based on temperature measurements. Blood sugar levels obtained by non-invasive measurements of temperatures are corrected by blood oxygen saturation and the volume of blood flow so that the measurement data can be stabilized.

Blood sugar levels are non-invasively measured based on temperature measurements. Blood sugar levels obtained by non-invasive measurements of temperatures are corrected by blood oxygen saturation and the volume of blood flow so that the measurement data can be stabilized.

Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data.

Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data. If the measured blood sugar level is larger than a warning value, a warning is issued.

Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data. A guide is provided for guiding an analyte to a measurement portion.

Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data. The shape or color of control buttons for controlling measurement are associated with the function of each button such that the buttons can be identified either visually or by touch.

Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data.

Luminal endoprosthesis formed of a multi-layer braided framework. The framework is devoid of any cover layer, and formed of a plurality of stabilized layers of biocompatible metal wires which are interlaced, forming a lattice, a plurality of wires of a given layer being integrated in the lattice of the adjacent layers. The mechanical characteristics of an outermost layer is so that when in place, the layer applies against a vessel wall, the other layers extending substantially along cylindrical surfaces distinct from the outermost layer so as to form a multi-layer mat which affects the haemodynamic of a flow of blood passing along or through this mat and preventing a growing of plaque.

The scanning speed of a sample in Doppler OCT, etc., is increased to enable quick measurement of blood flow rate, blood flow volume, etc. Wideband light from a light source 2 is linearly polarized by a polarization controller 3 and this linearly polarized beam is split into vertically polarized light and horizontally polarized light using a Wollaston prism 14 at a sample arm, which are then irradiated simultaneously onto two different locations of the sample in the scanning direction using a galvanometer mirror18, and reference light from a reference arm 5 and object light from a sample arm 6 are merged and caused to interfere with each other, with the resulting interference signal light passed through a diffraction grating 26 for spectroscopy, while the horizontal component and vertical component are separated by a polarized beam splitter 28, to simultaneously measure the components with two polarization-sensitive optical detectors 29, 30 and thereby obtain two tomography images of the same location at different times by one mechanical scan, thus allowing the amount of temporal change in phase to be measured using the two tomography images.

This invention relates to methods and devices providing transmyocardial blood flow or coronary revascularization for the treatment of coronary atherosclerosis and resulting myocardial ischemia by increasing the flow of blood from one or more oxygenated blood sources within the patient to one or more sites selected in the arterial vascular system of the heart using a channel for maintaining and regulating blood flow therebetween. A valved conduit or a self-maintained channel is created between the left ventricle reservoir of oxygenated blood and the coronary artery distal to an area of obstruction by surgical and percutaneous methods. Preferably, the conduit or self-maintained channel integrally regulates the flow of blood between the oxygenated blood source and the site selected in the arterial vascular system of the heart wherein an increase in blood flow is desired.

A method and apparatus for the prevention of deep vein thrombosis (DVT), pulmonary embolism (PE), lower extremity edema, and other associated medical conditions by adjusting the temperature of the muscles of a foot or a leg, and / or applying vacuum or negative pressure to increase blood flow. A human extremity such as a leg is exposed to a negative pressure environment and / or a thermally controlled environment within a medical device. In one aspect, the device is portable. A thermal exchange unit and, optionally, a vacuum or negative pressure unit, are provided to increase blood flow and vasodilation. The device can be programmed by a controller in a manner to stimulate the muscles of the extremity to reduce pooling of blood therein.

A method for increasing circulation and providing oxygen to a patient in cardiac arrest includes the step of coupling an interface to the patient's airway, the interface providing access to the patient's respiratory system. A valve system is operably attached to the interface. Oxygen is delivered through the interface a rate of between about 1.0 to about 10.0 L / min to provide a continuous supply of oxygen to the patient. While supplying the oxygen, a body structure of the patient is manipulated to increase the magnitude and duration of the patient's negative intrathoracic pressure. During the manipulation, the valve system prevents additional respiratory gases from entering the lungs until a negative intrathoracic pressure level in the range from about −1 cm H2O to about −15 cm H2O, the valve system assisting in increasing the magnitude and duration of negative intrathoracic pressure thereby enhancing the amount of blood flow in the heart and lungs and lowering intracranial pressure, therein further increasing blood flow to the brain.

A method of blood flow monitoring for a patient, the method comprising the steps of: a) receiving a first signal indicative of the real time cardiac output for the patient; b) processing the continuous wave Doppler signal to provide an estimate of blood flow velocity as a function of time; c) receiving a pressure measurement indicative of the blood flow resistance through the patient; and d) calculating an Inotropy measure indicative of the potential and kinetic energy of the cardiac output of the patient.

A 2D or 3D velocity field is reconstructed from a cross-correlation analysis of image pairs of a sample, without first reconstructing images of the sample spatial structure. The method can be implemented via computer tomographic x-ray particle image velocimetry, using multiple projection angles, with phase contrast images forming dynamic speckle patterns. Estimated cross-correlations may be generated via convolution of a measured autocorrelation function with a velocity probability density function, and the velocity coefficients iteratively optimised to minimise the error between the estimated cross-correlations and the measured cross-correlations. The method may be applied to measure blood flow, and the motion of tissue and organs such as heart and lungs.

A method for monitoring cardiac output (pulmonary blood flow) of a subject, the method including: measuring a first net pulmonary uptake or elimination of a breathed gas species by the subject and a first partial pressure of the gas species at a first time, and at a second time later than the first time, determining a first pulmonary blood flow of the patient at the first time, and determining a pulmonary blood flow of the subject at the second time on the basis of the first pulmonary blood flow, the first net pulmonary uptake or elimination, the second net pulmonary uptake or elimination, the first partial pressure, and the second partial pressure.

An apparatus and methodological framework are provided, named perfusion angiography, for the quantitative analysis and visualization of blood flow parameters from DSA images. The parameters, including cerebral blood flow (CBF) and cerebral blood volume (CBV), mean transit time (MTT), time-to-peak (TTP), and Tmax, are computed using a bolus tracking method based on the deconvolution of time-density curves on a pixel-by-pixel basis. Individual contrast concentration curves of overlapping vessels can be delineated with multivariate Gamma fitting. The extracted parameters are each transformed into parametric maps of the target that can be color coded with different colors to represent parameter values within a particular set range. Side by side parametric maps with corresponding DSA images allow expert evaluation and condition diagnosis.

There is provided a method for controlling a flow of fluid in the vas deferens in order to obtain a controlled male contraception. The method comprises gently constricting (i.e., without substantially hampering the blood circulation in the tissue wall) at least one portion of the tissue wall to influence the flow vas deferens, and stimulating the constricted wall portion to cause contraction of the wall portion to further influence the flow in the vas deferens. The method can be used for restricting or stopping the flow in the vas deferens, or for actively moving the fluid in the vas deferens, with a low risk of injuring the organ.

A prior application discloses a novel probe geometry that offers a wide field of view in an ultrasonic imaging device. That geometry is referred to as a "thinned array" of transducer elements. The application discloses an improved probe geometry permitting high-resolution imaging of a large volume of the subject's body. In this improved geometry, the array elements are non-uniform in size and spacing. The probe is intended for use, for example, in a method of determining parameters of blood flow, such as vector velocity, blood flow volume, and Doppler spectral distribution, using sonic energy (ultrasound) and a novel thinned array. Also in a method of tracking blood flow and generating a three dimensional image of blood vessel of interest that has much greater resolution than images produced using heretofore known ultrasound devices and methods.

The invention relates to an opto-acoustic brain function imaging method. The method realizes imaging of brain blood vessel structure distribution observation and function monitoring via the opto-acoustic tomographic image of the cortex blood vessels. Brain damage and cerebral hemorrhage variation degree can be monitored, and the parameters such as cerebral blood flow, brain oxygen consumption and brain oxygen saturation etc can be reflected via the blood vessel form distribution, blood diameter variation and opto-acoustic signal intensity variation of blood vessels. The laser generation component, acoustic signal acquisition component and computer among the devices realizing the mentioned method are electrically connected in turn. The rotary scanning mechanism is electrically connected with the computer. The sample fixation components are connected with the acoustic coupling components in turn. The invention is characterized by convenient operation and sensitive and quick performance, can make imaging analysis of blood vessels without damage, and then monitor brain function, which can thus provide imaging basis for brain function judgment.

A method is provided for increasing blood flow in or about a cardiac structure to prevent thrombosis. One step of the method includes providing an implantable sprayer having an elongated tubular body with proximal and distal end portions. The distal end portion includes at least one opening and an anchoring mechanism. The distal end portion of the implantable sprayer is inserted into a cardiac chamber that includes the cardiac structure. The anchoring mechanism is then deployed so that the distal end portion of the implantable sprayer is secured in or about the cardiac structure. Next, the proximal end portion is anastomosed with an artery so that blood flows through the elongated tubular body of the implantable sprayer and is sprayed out of the at least one opening to continuously circulate blood in or about the cardiac structure.

A medical blood access system used for hemodialysis treatment to enable blood withdrawal for processing of blood by an external apparatus and return the same blood to a patient, comprising an interfacial fluid conduit between the machine and patient's blood supply which is repeatedly connectable along a guided pathway passing through epidermis and subcutaneous tissue via a naturally formed tissue tract to enter blood space, providing improved patient safely, convenience, effective prophylaxis, without bleeding or tissue trauma or pain, and is executable by the patient to precisely connect and disconnect with minimal disfigurement or life restrictions, and is useable on virtually all patients soon after placement and is robust and safe to high blood flow.

A heart-rate sensor for detecting artery blood-flow volume per unit length change in a human or animal subject, which comprises an antenna for sensing the instantaneous volume of blood in the artery of the subject, to be measured; a RADAR unit for transmitting microwave signals into a subject's body part or limb representing tissue targets. The output of the RADAR unit includes a superposition of signals each of which corresponding to a different tissue target with amplitudes that relate to the target's reflection strength; a sampling circuitry for converting reflected signals to digital; a window function circuitry for suppressing unwanted spectral sidebands originating from the subsequent processor operating on time truncated data; an FFT processor following the window function circuitry, for splitting the superposition according to its relative frequency into a multiplicity of bins, each of which with an amplitude that represents the reflection magnitude of a target at a specific distance from the antenna; a signal processor for filtering out the effect of the sensor movement with respect to the subject body part, or the movement of the body part, and for generating a signal, the amplitude of which is proportional to the artery varying dilatation representing the heart-rate; a heart-rate estimator for measuring the frequency of the artery dilatation variations and for canceling the interference of the amplitude of any signal that does not originate from the artery; a battery for powering the sensor.