194 results about "Doppler ultrasound" patented technology

A wireless fetal and maternal monitoring system includes a fetal sensor unit adapted to receive signals indicative of a fetal heartbeat, the sensor optionally utilizing a Doppler ultrasound sensor. A short-range transmission unit sends the signals indicative of fetal heartbeat to a gateway unit, either directly or via an auxiliary communications unit, in which case the electrical coupling between the short-range transmission unit and the auxiliary communications unit is via a wired connection. The system includes a contraction actuator actuatable upon a maternal uterine contraction, which optionally is a EMG sensor. A gateway device provides for data visualization and data securitization. The gateway device provides for remote transmission of information through a data communication network. A server adapted to receive the information from the gateway device serves to store and process the data, and an interface system to permits remote patient monitoring.

Provided herein is a method for use in medical applications that permits (1) affordable three-dimensional imaging of blood flow using a low-profile easily-attached transducer pad, (2) real-time blood-flow vector velocity, and (3) long-term unattended Doppler-ultrasound monitoring in spite of motion of the patient or pad. The pad and associated processor collects and Doppler processes ultrasound blood velocity data in a three dimensional region through the use of a planar phased array of piezoelectric elements. The invention locks onto and tracks the points in three-dimensional space that produce the locally maximum blood velocity signals. The integrated coordinates of points acquired by the accurate tracking process is used to form a three-dimensional map of blood vessels and provide a display that can be used to select multiple points of interest for expanded data collection and for long term continuous and unattended blood flow monitoring. The three dimensional map allows for the calculation of vector velocity from measured radial Doppler.

A thinned array (greater than half-wavelength element spacing of the transducer array) is used to make a device of the present invention inexpensive and allow the pad to have a low profile (fewer connecting cables for a given spatial resolution). The full aperture is used for transmit and receive so that there is no loss of sensitivity (signal-to-noise ratio) or dynamic range. Utilizing more elements (extending the physical array) without increasing the number of active elements increases the angular field of view. A further increase is obtained by utilizing a convex non-planar surface.

A method of full-field or “ping-based” Doppler ultrasound imaging allows for detection of Doppler signals indicating moving reflectors at any point in an imaging field without the need to pre-define range gates. In various embodiments, such whole-field Doppler imaging methods may include transmitting a Doppler ping from a transmit aperture, receiving echoes of the Doppler ping with one or more separate receive apertures, detecting Doppler signals and determining the speed of moving reflectors. In some embodiments, the system also provides the ability to determine the direction of motion by solving a set of simultaneous equations based on echo data received by multiple receive apertures.

Minimally invasive systems and methods are described for measuring pulmonary circulation information from the pulmonary arteries. A transbronchial Doppler ultrasound catheter is advanced through the airways and in the vicinity of the pulmonary artery. Doppler ultrasound energy is sent through the airway wall and across the pulmonary artery to obtain velocity information of blood flowing through the artery. The velocity information is used to compute pulmonary circulation information including but not limited to flowrate.

A medical diagnostic system, the system comprising:

a) a non-ultrasound imaging module configured to generate a volumetric vascular map;

b) a controller configured to translate a 3D position co-ordinate from the map into an aiming instruction;

c) a Doppler ultrasound unit adapted to aim a transducer responsive to the aiming instruction; and

d) a registration module configured to register a position of the transducer with respect to the volumetric map.

A pulse Doppler ultrasound system and associated methods are described for monitoring blood flow and hemodynamics. The Doppler ultrasound system includes an ultrasound probe to emit ultrasound signals and detect reflected signals therefrom and further includes a processor coupled to the ultrasound probe and operable to process the detected reflected signals and calculate therefrom blood flow data for a plurality of locations at time intervals, the processor further operable to identify locations at which blood flow having a hemodynamic characteristic is present based on the blood flow data calculated for a plurality of the time intervals. A user interface coupled to the processor provides blood flow information based on the blood flow data, the blood flow information representative of detected blood flow and the presence of the hemodynamic characteristic.

Method and apparatus to non-invasively measure fetal blood oxygen saturation levels. Optical sensors capable of producing and detecting multiple wavelengths of tissue penetrating light are placed on the surface of the maternal abdomen, and the light beams directed to pass through at least a portion of the uterus containing the fetus. The fetal heart rate is monitored by Doppler ultrasound, and pure maternal optical signal related to maternal arterial blood flow are also measured. The optical sensors collect composite signals containing both maternal and fetal hemoglobin absorption spectral data and modulated by their respective pulsatile blood flows. The composite signals processed in the time domain and frequency domain, the pure maternal pulsatile optical signal used to extract the maternal contribution to the composite signal, and the fetal pulsatile signal is used to lock onto and extract the fetal contribution to the composite signal, and a fetal blood oxygen level deduced.

Tracheostomy apparatus includes a needle with a doppler ultrasound transducer mounted within it close to its patient end and connected to a monitor. Two electrodes are insulated from one another on the external surface of the needle close to its patient end. The electrodes are also connected to the monitor. The needle supports a catheter on its outer surface. As the needle is inserted through tissue overlying the trachea, the ultrasound transducer detects the presence of any nearby blood vessels and gives an audible indication on the monitor. The monitor also responds to a rise in impedance between the electrodes indicative of entry of the end of the needle into the trachea so that the needle can be removed to leave the catheter in place. A guide is then inserted through the catheter and the path into the trachea is enlarged with a dilator sufficiently to receive a tracheostomy tube.

An ultrasonic Doppler probe is provided for use in connection with non-invasive Doppler imaging of fluid flow within the human body. The Doppler probe can be selectively operated at more than one frequency during the course of a Doppler imaging examination thereby enhancing the resolution of the image obtained while also increasing the effective depth of the image. The probe of the present invention employs piezo-electric materials for the formation of acoustic transmitting and receiving transducers that are positioned within the probe to allow the probe to be selectively operated at a number of different frequencies spanning no more than one octave in frequency range.

A Doppler ultrasound signal processing system for processing reflected ultrasound signals detected by an ultrasound transducer for multiple carrier frequencies concurrently. Additionally, an embolus characterization system and method, and an ultrasound transducer are included as well.

An apparatus, method and system comprising an imaging tool for imaging an interventional device and its target organ using Doppler ultrasound are disclosed. The apparatus comprises an imaging tool and an interventional medical device; in some embodiments the imaging tool itself may be an interventional device or may comprise components of the interventional device. The imaging tool comprises a vibratory transducer and a vibratable element. The vibratory transducer is energized to generate a vibration motion in the vibratable element at first imaging frequency, which in turn is capable of oscillating a target organ at a second imaging frequency, the imaging frequencies being detectable by an ultrasound imaging system with Doppler mode. In certain applications the vibratory transducer may be energized to vibrate at a therapeutic frequency to effect treatment of the target organ, for example to clear a lumenal or vascular stenosis or to penetrate a vascular occlusion.

Doppler ultrasound may be used to detect stenosis in a blood vessel using a variety of approaches. In one approach, the flow envelope is extracted from the Doppler ultrasound measurements, and the extracted flow envelope is parameterized. Classification is then done based on those parameters (and optionally other parameters), to determine whether a stenosis exists. A second approach uses Doppler data that is acquired in a direction that is perpendicular to the direction of blood flow, and detects artifacts that are consistent with turbulences that usually appear downstream from stenoses.

A apparatus for automatically detecting a pregnancy status of a patient include a patch for adhering to human skin, a uterine contraction sensor, such as electromyography (EMG), coupled to the patch with at least two electrodes, and an inertial sensor for sensing fetal movement, or fetal heart rate (FHR) sensor, such as fetal EKG or a Doppler ultrasound. An electronic circuit is coupled to the patch, the EMG sensor and the inertial sensor, and/or FHR sensor. The circuit provides an output based on a uterine contraction signal from the EMG sensor (or the Doppler ultrasound) correlated in time to a fetal movement, and/or fetal heart rate. The apparatus may include a thermometer to aid in automatically providing an indication of a pregnancy complication or ovulation status of the patient, based on the output.

The invention provides a multi-parameter-based intracranial pressure noninvasive detection method and device. The method comprises the following steps of: pre-establishing an intracranial pressure evaluation function model for recording a function mapping relation between the change of the intracranial pressure and the changes of an electrocardiosignal, a visual evoked potential signal, a brain impedance signal and a transcranial Doppler ultrasonic signal and setting in a computer; and synchronously acquiring the electrocardiosignal, the visual evoked potential signal, the brain impedance signal and the transcranial Doppler ultrasonic signal into a computer and inputting the signals serving as the intracranial pressure evaluation function model to obtain the dynamic change process waveform of the intracranial pressure of an inspected object by performing multi-parameter and multi-direction operation. Due to the adoption of the method, invasive intracranial pressure detection is avoided; the device for implementing the method is easy to obtain; and meanwhile, various physiological and pathological signal parameters causing the change of the intracranial pressure are considered comprehensively in the intracranial pressure evaluation function model, so that the intracranial pressure noninvasive detection method has higher clinical detection accuracy.