Search results
Results from the WOW.Com Content Network
Meanwhile, spectral Doppler ultrasonography consists of three components: B-mode, Doppler mode, and spectral waveform displayed at the lower half of the image. Therefore, "duplex ultrasonography" is a misnomer for spectral Doppler ultrasonography, and more exact name should be "triplex ultrasonography".
Duplex ultrasound (duplex) combines standard B-mode ultrasound and Doppler ultrasonography to evaluate both structural details of the carotid arteries and blood flow through the arteries. [2] During carotid duplex evaluation, the 2D B-mode structural image is superimposed with the doppler flow data, which provides a more realistic anatomical ...
An ultrasonic examination. Ultrasound is sound with frequencies greater than 20 kilohertz. [1] This frequency is the approximate upper audible limit of human hearing in healthy young adults.
Functional transcranial Doppler sonography (fTCD) is a neuroimaging tool for measuring cerebral blood flow velocity changes due to neural activation during cognitive tasks. [8] Functional TCD uses pulse-wave Doppler technology to record blood flow velocities in the anterior, middle, and posterior cerebral arteries.
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 ...
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Help; Learn to edit; Community portal; Recent changes; Upload file
Pseudonormal (E:A ratio appears normal) Restrictive filling (E:A ratio often > 2) Pseudonormalisation shows a transmitral profile that appears normal. However, with the use of pulmonary vein pulsed wave Doppler, it can be shown that the relaxation pattern is abnormal (systolic blunting, a decrease in the height of the S wave).
Ultrasound Doppler imaging can be used to obtain basic functional measurements of brain activity using blood flow. In functional transcranial Doppler sonography, a low frequency (1-3 MHz) transducer is used through the temporal bone window with a conventional pulse Doppler mode to estimate blood flow at a single focal location.