Christian Andreas Doppler was born in Salzburg, Austria, on November 29, 1803. His father was a stonemason, and he was expected to join the family business, but due to his poor health condition, he persuaded academics. He graduated in physics from the Polytechnical Institute of Vienna in 1825 and later, he went to the University of Vienna to study mathematics, machines, and astronomy.[1] At the end of his study, he has worked with Professor Burg for 4 years and in 1831, he published his first paper “A contribution to the theory of parallels.”[1] Unfortunately, for many years, he failed to get an academic position, so he supported himself by working as a bookkeeper at a cotton factory near the city of Bruck. He was disappointed and decided to move to the USA where he was offered a position as a professor at the Technical Secondary School in Prague and later at the polytechnic school. In 1836, he married Mathilda Sturm and together the couple had five children.
2. Vashistha and Das: Christian Doppler
Journal of the Practice of Cardiovascular Sciences ¦ Volume 5 ¦ Issue 1 ¦ January-April 201954
of the moving target (v), transmitted frequency (ft), and
the angle between the direction of ultrasound beam and the
direction of the moving target, which is similar to the Doppler
equation.[5]
The information that is obtained from Doppler
echocardiography is flow velocity, direction of the flow, the
timing of the signal with the cardiac events, and intensity of
the flow. There are two forms of Doppler echocardiography:
the pulse wave and continuous wave.
The pulse‑wave Doppler samples velocity in a particular site
in the form of a pulse; therefore, limited range information can
be picked up. Color Doppler is based on pulse‑wave Doppler
and is mainly used to pick up valvular disease.[6]
Continuous‑wave Doppler transmits and receives continuous
signals from moving red blood cells. Continuous‑wave Doppler
is used in the evaluation of valve stenosis or regurgitation and
indirectly, it is used in determining the pulmonary arterial
systolic pressure.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
1. Coman IM. Christian Andreas Doppler – The man and his legacy. Eur J
Echocardiogr 2005;6:7‑10.
2. White DN. Johann Christian Doppler and his effect – A brief history.
Ultrasound Med Biol 1982;8:583‑91.
3. Holen J, Aaslid R, Landmark K, Simonsen S. Determination of pressure
gradient in mitral stenosis with a non‑invasive ultrasound Doppler
technique. Acta Med Scand 1976;199:455‑60.
4. Hatle L, Brubakk A, Tromsdal A, Angelsen B. Noninvasive assessment
of pressure drop in mitral stenosis by Doppler ultrasound. Br Heart J
1978;40:131‑40.
5. Anavekar NS, Oh JK. Doppler echocardiography: A contemporary
review. J Cardiol 2009;54:347‑58.
6. Katsi V, Felekos I, Kallikazaros I. Christian Andreas Doppler:
A legendary man inspired by the dazzling light of the stars. Hippokratia
2013;17:113‑4.
[Downloaded free from http://www.j-pcs.org on Sunday, June 30, 2019, IP: 117.237.220.216]