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The penetration depth of X-rays in water as function of photon energy. Penetration depth is a measure of how deep light or any electromagnetic radiation can penetrate into a material. It is defined as the depth at which the intensity of the radiation inside the material falls to 1/ e (about 37%) of its original value at (or more properly, just ...
Prehospital ultrasound is the specialized application of ultrasound by physicians and other [1] emergency medical services [2] (EMS) to guide immediate care and treatment procedures. [3] Like conventional ultrasound, it is a device that produces cyclic sound pressure to penetrate a medium (different body tissues) and reveal details about the ...
The ultrasound waves generated from this device allow for penetration through biological tissue by molecular oscillation of the biological tissue they travel through. [ 1 ] [ 3 ] The amplitude of the wave can be modified by manipulating the displacement of the ultrasound horn for each half cycle as they are proportional.
The motion artifact can be particularly problematic for clinical use. [5] Though ULM achieves resolutions under 10 micrometers, "motion in the body or from the ultrasound transducer can be several orders of magnitudes beyond this level". [3] [11] For example, body motion could be on the scale of 0.5 mm, while ULM resolutions may be 5 to 10 ...
[1] [2] Many existing cancer treatment strategies cause systemic toxicity or cannot penetrate tissue deep enough to reach the entire tumor; however, emerging ultrasound stimulated therapies could offer an alternative to these treatments with their increased efficiency, greater penetration depth, and reduced side effects. Sonodynamic therapy ...
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.
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 near-infrared (NIR) window (also known as optical window or therapeutic window) defines the range of wavelengths from 650 to 1350 nanometre (nm) where light has its maximum depth of penetration in tissue. [1] Within the NIR window, scattering is the most dominant light-tissue interaction, and therefore the propagating light becomes diffused ...