Impulse Doppler study transmits ultrasound impulses in series . With this new pulse is sent after receiving reflected signal .
Required temporary delay for registration reflected signal limits maximum cha stota transmission pulses . therefore the mode not fits for registration high speed flows .
With speeds more than 2 m / s arises change by lariness blood flow, known as Effect distortions spectrum .
Impulse Doppler study provide begs the best quality spectrum at comparing with constantly wave that It has important value at calculations .
Impulse Doppler study used are calling for accurate localization abnormal speed streams identified at constantly – wave extra Plerovo research and colored doppler mapping .Indicators transmitral blood flow use for ratings diastolic functions left ventricle ( LV ). Indicators transaortic kro water flow use for calculations shock volume and cordial ejection .
PHYSICAL PRINCIPLES
Color Doppler study is an automat tizirovannymi option pulsed doppler research . Also this mode called doppler skim by research at real of time .
Color Doppler study allows in and zualize intracardiac blood flow at the form color cards blood flow . Color mapping blood flow sometimes called ” Non-invasive angiography, “so asat the same time men with information about functions rate and anatomy . After Togo as series pulses transmitted along one the lines scan by analogies with pulsed dopple rovskyresearch is reflected from red blood cells, is performed her analysis autocorrelator echocardiograph .
Autocorrelator compares frequency reflected signal with original frequency. After of this difference frequencies assigned to certain Colour by to a certain to the algorithm .
Analysis sets control volumes along each of sets lines scan allows to create coded different flowers card about land interest .
AT color map blood flow encoded information tion as about speed, so and about direction blood flow . With overlay color cards blood flow on grayish two-dimensional pictureappears opportunity is full valuable interpretations received information .
Flow directed to sensor, coded shade mi red as well directed from sensor – shades blue colors .
With increasing speeds blood flow shade blue or red colors becomes more light . So way low speeds seem dark as well high cue – bright and light .
Turbulent high speed blood flow mapping is at colored doppler mode at the form mosaic flow with shades blue, green, and yellow flowers .
Like Effect changes colors underlines high speed blood flow and arises at connections with is by sight doppler spectrum at mode pulsed Doppler – echocardiography .