摘要:
In a method and apparatus (400), a property of an optically diffuse medium comprising a first optical absorber having a first concentration and a second optical absorber having a second concentration is determined. A surface area (406) of the medium is imaged at multiple wavelengths around an isosbestic wavelength of the first absorber and the second absorber. A reflectance spectrum of the medium at the surface area at the multiple wavelengths is determined. A derivative of the determined reflectance spectrum around the isosbestic wavelength is determined. From the derivative, a concentration ratio of the first concentration and the second concentration is estimated.
摘要:
The technology described in this document can be embodied in a method that includes receiving optical data including information associated with a subject, and determining from the optical data, a first and a second dataset. The first dataset represents time-varying color change at a first body part of the subject. The second dataset represents time-varying characteristics at a second body part of the subject. The method includes identifying a first point in the first dataset, and a second point in the second dataset. The first point represents a time at which a pulse pressure wave traverses the first body part of the subject, and the second point represents a time at which the pulse pressure wave traverses the second body part of the subject. A pulse transit time (PTT) between the first and second body parts can be calculated as a difference between the first and second points.
摘要:
Various examples are provided for non-contact vital sign acquisition. Information can be provided regarding vibrations of a target using a radar signal such as, e.g., non-contact vital sign measurement. Examples include estimation of heart rate, change in heart rate, respiration rate, and/or change in respiration rate, for a human or other animal. Implementations can produce one or both rates of vibration and/or change in one or both rates of vibration for a target other than an animal or human experiencing two vibrations at the same time, such as a motor, a vehicle incorporating a motor, or another physical object. Some implementations can estimate the respiration movement in the radar baseband output signal. The estimated respiration signal can then be subtracted from radar signals in the time domain and, optionally, can be further enhanced using digital signal processing techniques, to produce an estimate of the heartbeat pulses.
摘要:
Medical devices and methods for making and using medical devices are disclosed. An example method may include a method of identifying an activation time in a cardiac electrical signal. The method may include sensing a cardiac electrical signal, generating an approximation signal based at least in part on one or more parameters of the cardiac electrical signal, identifying a fiducial point on the approximation signal and determining, based at least in part on a timing of the fiducial point in the approximation signal, an activation time in the cardiac electrical signal.
摘要:
System or method for treating heart tissue can include a control system and catheter device operated in a manner to intermittently occlude a heart vessel for controlled periods of time that provide redistribution of blood flow. The system can be configured to provide an estimation of the cumulative effects of the treatment. For example, the system or method can treat myocardium that is at risk of infarction by intermittently altering blood flow in a venous system to induce microcirculation within the myocardium, and can output a cumulative dosage value indicative of a measurement of progress of reducing an infarct size.
摘要:
The invention relates to a method and device including a system for identification and monitoring of pulmonary data. The invention allows for the collection of pulmonary function test data as well as the ability to compare and correlate newly collected data with historic patient data. The invention also allows for the ability to identify individual patients based on the analysis of pulmonary characteristics unique to the individual, such as measures of lung function to ensure integrity of a patient's historical data.
摘要:
A system and method are provided for determining electrophysiological data. The system comprises an electronic control unit that is configured to receive electrical signals from a set of electrodes, receive position and orientation data for the set of electrodes from a mapping system, compensate for position and orientation artifacts of the set of electrodes, compose cliques of a subset of neighboring electrodes in the set of electrodes, determine catheter orientation independent information of a target tissue, and output the orientation independent information to a display. The method comprising receiving electrogram data for a set of electrodes (80), compensating for artifacts in sensor positions in the mapping system (81), resolving the bipolar signals into a 3D vector electrogram in the mapping system coordinates (82), manipulating observed unipolar voltage signals and the tangent component of the e-field to estimate the conduction velocity vector (83), and outputting the catheter orientation independent information (84).
摘要:
The invention provides a body-worn system that continuously measures pulse oximetry and blood pressure, along with motion, posture, and activity level, from an ambulatory patient. The system features an oximetry probe that comfortably clips to the base of the patient's thumb, thereby freeing up their fingers for conventional activities in a hospital, such as reading and eating. The probe secures to the thumb and measures time-dependent signals corresponding to LEDs operating near 660 and 905 nm. Analog versions of these signals pass through a low-profile cable to a wrist- worn transceiver that encloses a processing unit. Also within the wrist- worn transceiver is an accelerometer, a wireless system that sends information through a network to a remote receiver, e.g. a computer located in a central nursing station.
摘要:
A method for detecting the onsets or offsets of heart depolarization or repolarization waves (e.g. QRS-complex or T-wave) includes determining a slope of a cardiac electrogram. A threshold value is determined based on a maximum of the slope of the cardiac electrogram, and a last point of the cardiac electrogram before the slope of the cardiac electrogram crosses the threshold is identified as one of an onset or an offset of a wave. The method may further include receiving an indication of local ventricular motion associated with a cardiac contraction, and determining an electromechanical delay between the identified onset and the local ventricular motion. Some examples include providing the electromechanical delay for configuration of cardiac resynchronization therapy (CRT), e.g. selection of pacing sites.
摘要:
본 발명은 생체의 생리적 특성을 측정하기 위한 생체 신호 처리방법을 개시한다. 본 발명에 따른 생체 신호 처리방법은: 서로 다른 파장 대역을 가지며 상기 생체의 생리적 특성을 나타내는 두 개의 신호 함수들 중 어느 하나의 신호 함수 P 1 (t)에 대한 미분 P 1 '(t)를 다른 하나의 신호 함수 P 2 (t)에 대한 미분 P 2 '(t)로 나누는 (a)단계; 그리고 하기 수학식 1을 이용하여 하기 함수 n 1 (t)의 상수 b와 함수 s 1 (t)의 주기를 획득하는 (b)단계를 포함하여 이루어진다. [수학식 1] (P 1 '(t)/P 2 '(t))| t=t1, t2, t3,… =k (상기 수학식 1에서, P 1 (t)=s 1 (t)+n 1 (t), P 2 (t)=s 2 (t)+n 2 (t), as 1 (t)=s 2 (t), bn 1 (t)=n 2 (t), a와 b와 k는 상수, 변수 t는 시간, n 1 (t)과 n 2 (t)는 각각 생체 신호 측정시 노이즈(Noise)에 의한 신호 함수임) 본 발명에 따르면, 사용자가 원하는 데이터, 즉 노이즈 성분이 제거된 데이터의 신호 주기를 간단한 처리과정을 통해 추출할 수 있으므로, 생리적 특성의 검출을 위해 소요되는 과정이 간략화될 수 있다.