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In physics, Continuous-wave (CW) Doppler is an ultrasound technique that continuously transmits and receives sound waves. This allows for the measurement of very high blood flow velocities, crucial in medical diagnostics where precise speed is paramount. Unlike pulsed-wave Doppler, CW Doppler doesn't suffer from aliasing, making it ideal for assessing rapid, turbulent flows in conditions…

In physics, wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It's a fundamental property of sound waves, light, and other periodic waves, inversely proportional to frequency. In medical ultrasound, understanding wavelength is critical, as it directly influences image resolution and penetration depth. Shorter wavelengths (higher frequencies) provide…

In physics, attenuation signifies the gradual loss of intensity as energy, such as sound waves or light, travels through a medium due to absorption or scattering. This fundamental concept is crucial in various scientific fields, including medical imaging and ultrasound, where understanding how sound waves lose energy in tissues directly impacts image quality and diagnostic…

In physics, reflection is the phenomenon where a wave, such as an ultrasound wave, bounces off a boundary between two different media, redirecting its path. This fundamental principle is crucial in medical ultrasound, as the echoes received by the transducer are reflections of sound waves from internal body structures. The degree of reflection depends on…

In physics, refraction is the bending of a wave as it passes from one medium to another, caused by a change in its speed. In medical ultrasound, this phenomenon occurs when sound waves encounter an interface between tissues with different propagation speeds, leading to a change in direction. This bending can distort the ultrasound image,…

In physics, scattering describes the redirection of waves, like sound or light, as they encounter obstacles or inhomogeneities within a medium. This fundamental phenomenon is crucial in medical imaging, particularly in ultrasound, where sound waves interact with various tissues. Understanding scattering helps explain the speckled appearance of ultrasound images and how different tissues reflect sound.…

In physics, impedance is the opposition a system presents to the flow of energy. In the context of medical ultrasound, acoustic impedance is a critical property of tissue, defined as the product of tissue density and the speed of sound within that tissue. This fundamental concept dictates how sound waves behave at interfaces between different…

In physics, the Doppler effect describes the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source. When the source and observer are moving closer, the frequency appears higher (shorter wavelength), and when they are moving apart, the frequency appears lower (longer wavelength). This…

In ultrasound physics, Pulse Repetition Frequency (PRF) is a critical parameter referring to the number of ultrasound pulses emitted by the transducer per second. Measured in Hertz (Hz) or kilohertz (kHz), PRF directly influences the maximum depth from which echoes can be accurately received before the next pulse is sent. A higher PRF allows for…