Ki sa ki koulè Doppler Flow Imaging?
Koulè Doppler D' koule (CDFI), ke yo rele tou de -Doppler, sèvi ak deteksyon faz, pwosesis otokorrelasyon, ak kodaj koulè gri an mwayèn Done vitès sikilasyon san yo parèt an koulè epi konbine ak supèrpoze sou B{ {1}}mode imaj gri. Li montre sikilasyon san plis entwisyon, epi li ka montre pwopriyete sikilasyon san ak distribisyon vitès koule nan kè a ak veso sangen yo pi vit ak plis entwisyon pase Doppler batman kè. Li gen avantaj inik nan ekspozisyon goch-a-dwat shunt san koule ak valv regurgitation san koule. Men, quantification nan sikilasyon san se pa bon jan vag batman kè ak vag kontinyèl Doppler.
Color Doppler flowmeter, like pulse wave and continuous wave Doppler, also uses the Doppler effect between red blood cells and ultrasound to achieve imaging. Color Doppler flowmeter includes two-dimensional ultrasound imaging system, pulse Doppler (one-dimensional Doppler) blood flow analysis system, continuous wave Doppler blood flow measurement system and color Doppler (two-dimensional Doppler) ) blood flow imaging system. The oscillator generates two quadrature signals with a difference of π/2, which are respectively multiplied by the Doppler blood flow signal. , after removing the low-frequency components generated by the vessel wall or valve, etc., it is sent to the autocorrelator for autocorrelation detection. Since each sampling contains the Doppler blood flow information produced by many red blood cells, the obtained signal is a mixed signal of multiple blood flow velocities after autocorrelation detection. The autocorrelation detection results are sent to the velocity calculator and the variance calculator to obtain the average velocity, which is stored in the digital scan converter (DSC) together with the blood flow spectrum information and two-dimensional image information after FFT processing. Finally, according to the direction and velocity of blood flow, the color processor encodes the blood flow data as pseudo-color and sends it to a color monitor for display, thereby completing color Doppler blood flow imaging.
Sous enfòmasyon eko yo jwenn nan D 'koule Doppler koule ki konsistan avèk Doppler espèk, distribisyon an ak direksyon sikilasyon san yo parèt nan de dimansyon, ak vitès diferan yo distenge pa koulè diferan. Sistèm ultrason Doppler Duplex, ki se yon imaj ultrason mòd B-ki montre kote veso sangen yo. Doppler mezire sikilasyon san, ak konbinezon sa a nan B-mòd ak sistèm Doppler ka lokalize pi presizeman nenpòt veso sangen bay yo.
