Pulse wave doppler, Biology

Assignment Help:

Pulse wave  transducer has one Doppler  crystal. This crystal emits a short burst of ultrasound at a certain frequency [PULSE REPETITION FREQUENCY (PRF)].  The ultrasqund is reflected from moving rbc's  and is received by  the same crystal. 

2369_Pulse Wave Doppler.png

The pulse wave trbnsducer will not send out a new  burst of waves until  it has received returning echoes from previous pulse, which must travel to and Go  from the  location  indicdted by  the sample volume. The pulse wave Doppler gives velocity of blood now at the level of  sample volume placed along ultrasound beam.

Pulse repetition fitquency,  as well as transducer frequency, plays a role  in determining the maximum velocity  that can be measured using a pulsed Doppler method. These rellationships come into play  especially when  attempting to record or to measure  incteased velocities  that might occur in  the case of obstructive lesions  such as vilvular  stenosis. This maximal measured velocity  is called NYQUIST LIMIT.

The NYQUIST LIIMIT-It  is a sampling phenomenon, which limits the maximum  fiequemcy shift measurement to one half of  the  sampling frequency (PRF).

By  its nature, pulse wave Doppler is a sampling system while continuous wave Doppler is not. The nyquist limit  is  a theoretical maximum frequency that a sampling system can  accurately measure.


Related Discussions:- Pulse wave doppler

Zoology, what are the physical requirements to become a zoologist?

what are the physical requirements to become a zoologist?

List a few shortcomings of native starches, List a few shortcomings of nati...

List a few shortcomings of native starches which make it unacceptable in certain food applications. Lack of free-flowing properties of water repellence of the starch granules,

Explain the basic function and use of glycolysis, Q. What is the glycolysis...

Q. What is the glycolysis? And what are the products of this process? Glycolysis, the first stage of the aerobic cell respiration is a process in which glucose is degraded brok

Functions based on management principles, FUNCTIONS BASED ON MANAGEMENT PRI...

FUNCTIONS BASED ON MANAGEMENT PRINCIPLES: Planning: The objectives of nursing unit should be achieved through planning, good coordination and supervision. While planning nur

Which protein component include organic matter of skin, This main protein c...

This main protein component of connective tissue in mammals includes most of the organic matter of skin, bones, tendons, and teeth and occurs as fibrous inclusions in most other bo

Chromosomes and molecular homology, CHROMOSOME S AND MOLECULAR HOMOLOGY - ...

CHROMOSOME S AND MOLECULAR HOMOLOGY - The DNA content of diploid cells is similar. Hoyer et al in 1965 showed that DNA of humans was 100% similar with chimpanzee and 94%

Soils of tropical and temperate forests, Soils of Tropical and Temperate Fo...

Soils of Tropical and Temperate Forests Although soils of tropical forests are generally poor in nutrients they are able to maintain high productivity under natural conditions

Give detail explanation of aerobic exercises, Aerobic Exercises, Examples a...

Aerobic Exercises, Examples and their Do's and Don'ts In the aerobic exercises it requires activities performed for a longer period here we do like to mention certain activitie

Determine the assess mobility of prosthesis, Assess Mobility of Prosthesis ...

Assess Mobility of Prosthesis All implant-supported prostheses must be stable.  To detect mobility, place an explorer or scaler under the embrasures and apply gentle pressure i

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd