Search results
Results from the WOW.Com Content Network
Pulsus bisferiens, also known as biphasic pulse, is an aortic waveform with two peaks per cardiac cycle, a small one followed by a strong and broad one. [1] It is a sign of problems with the aorta , including aortic stenosis and aortic regurgitation , as well as hypertrophic cardiomyopathy causing subaortic stenosis.
Doppler ultrasonography consists of two components: brightness mode (B-mode) showing anatomy of the organs, and Doppler mode (showing blood flow) superimposed on the B-mode. Meanwhile, spectral Doppler ultrasonography consists of three components: B-mode, Doppler mode, and spectral waveform displayed at the lower half of the image.
A JVP waveform. The jugular venous pulsation has a biphasic waveform. The a wave corresponds to right atrial contraction and ends synchronously with the carotid artery pulse. The peak of the 'a' wave demarcates the end of atrial systole. The x descent follows the 'a' wave and corresponds to atrial relaxation and rapid atrial filling due to low ...
This mixing produces I(t) and Q(t). Phase coherence of the transmit signal is crucial for pulse-Doppler operation. In the diagram, the top shows phases of the wave-front in I/Q. Each of the disks shown in this diagram represent a single sample taken from multiple transmit pulses, i.e. the same sample offset by the transmit period (1/PRF).
The E/A ratio is measured by placing a pulsed wave Doppler across the mitral valve and measuring the velocities across the valve. Hence, there are other names for the test, such as transmitral velocity profile, transmitral flow profile, transmitral flow velocity profile or transmitral Doppler waveforms. [citation needed]
Carotid ultrasound is a low-cost, noninvasive, and accurate diagnostic imaging modality used to evaluate diseases of the carotid arteries. [2] It is most often used to diagnose carotid artery stenosis, a form of atherosclerosis, and has the capability to assess plaque morphology and characteristics. [1]
Doppler spectrum. Deliberately no units given (but could be dBu and MHz for example). This is an issue only with a particular type of system; the pulse-Doppler radar, which uses the Doppler effect to resolve velocity from the apparent change in frequency caused by targets that have net radial velocities compared to the radar device. Examination ...
Coupling multiple spatial channels with pulse-Doppler waveforms lends to the name "space-time." Applying the statistics of the interference environment, an adaptive STAP weight vector is formed. This weight vector is applied to the coherent samples received by the radar.