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Intensified ultrasound energy can be directed at cancer cells to heat them and kill them. Recent testing has shown that ultrasound can increase the effectiveness of cancer treatments such as chemotherapy and radiation therapy. This procedure is known as heat or hyperthermia therapy. By using the converted heat energy that ultrasound provides ...
Ultrasound can ablate tumors or other tissue non-invasively. [4] This is accomplished using a technique known as high intensity focused ultrasound (HIFU), also called focused ultrasound surgery. This procedure uses generally lower frequencies than medical diagnostic ultrasound (250–2000 kHz), but significantly higher time-averaged intensities.
Medical ultrasound includes diagnostic techniques (mainly imaging techniques) using ultrasound, as well as therapeutic applications of ultrasound. In diagnosis, it is used to create an image of internal body structures such as tendons, muscles, joints, blood vessels, and internal organs, to measure some characteristics (e.g., distances and velocities) or to generate an informative audible sound.
The sign is an imaging finding using a 3.5–7.5 MHz ultrasound probe in the fourth and fifth intercostal spaces in the anterior clavicular line using the M-Mode of the machine. This finding is seen in the M-mode tracing as pleura and lung being indistinguishable as linear hyperechogenic lines and is fairly reliable for diagnosis of a pneumothorax.
Any sudden changes in direction of blood flow produces audible sounds on the ultrasound machine. [3] In spectral Doppler, the y-axis shows the direction and velocity of the flow. Meanwhile, the x-axis (as known as "baseline") shows the flow over time. The gradient at any point on the waveform would therefore shows the acceleration of the flow ...
Ultrasound computer tomographs use ultrasound waves to create images. In the first measurement step, a defined ultrasound wave is generated with typically Piezoelectric ultrasound transducers, transmitted in direction of the measurement object and received with other or the same ultrasound transducers. While traversing and interacting with the ...
These procedures generally use lower frequencies than medical diagnostic ultrasound (from 0.7 to 2 MHz), but higher the frequency means lower the focusing energy. HIFU treatment is often guided by MRI. Focused ultrasound may be used to dissolve kidney stones by lithotripsy. Ultrasound may be used for cataract treatment by phacoemulsification.
Ultrasound is defined by the American National Standards Institute as "sound at frequencies greater than 20 kHz". In air at atmospheric pressure, ultrasonic waves have wavelengths of 1.9 cm or less. Ultrasound can be generated at very high frequencies; ultrasound is used for sonochemistry at frequencies up to multiple hundreds of kilohertz.