What is Ultrasound?
Ultrasound or ultrasonography is a medical imaging technique that uses high frequency sound waves and their echoes. The technique is similar to the echolocation used by bats, whales and dolphins, as well as SONAR used by submarines. In ultrasound, the following events happen:
The ultrasound machine transmits high-frequency (1 to 5 megahertz) sound pulses into your body using a probe.
The sound waves travel into your body and hit a boundary between tissues (e.g. between fluid and soft tissue, soft tissue and bone).
Some of the sound waves get reflected back to the probe, while some travel on further until they reach another boundary and get reflected.
The reflected waves are picked up by the probe and relayed to the machine.
The machine calculates the distance from the probe to the tissue or organ (boundaries) using the speed of sound in tissue (5,005 ft/s or1,540 m/s) and the time of the each echo's return (usually on the order of millionths of a second).
The machine displays the distances and intensities of the echoes on the screen, forming a two dimensional image like the one shown belowUltrasound also has therapeutic applications, which can be highly beneficial when used with dosage precautions:
According to RadiologyInfo,ultrasounds are useful in the detection of pelvic abnormalities and can involve techniques known as abdominal (transabdominal) ultrasound, vaginal (transvaginal or endovaginal) ultrasound in women, and also rectal (transrectal) ultrasound in men. Treating benign and malignant tumors and other disorders via a process known as high intensity focused ultrasound (HIFU), also called focused ultrasound surgery (FUS). In this procedure, a generally lower frequencies than medical diagnostic ultrasound is used (250-2000 kHz), but significantly higher time-averaged intensities. The treatment is often guided by magnetic resonance imaging (MRI)—this is called Magnetic resonance-guided focused ultrasound (MRgFUS). Delivering chemotherapy to brain cancer cells and various drugs to other tissues is called acoustic targeted drug delivery (ATDD). These procedures generally use high frequency ultrasound (1-10 MHz) and a range of intensities (0-20 watts/cm2). The acoustic energy is focused on the tissue of interest to agitate its matrix and make it more permeable for therapeutic drugs.[17][18] Enhanced drug uptake using acoustic targeted drug delivery (ATDD).Therapeutic ultrasound, a technique that uses more powerful ultrasound sources to generate local heating in tissue: Used in occupational therapy, physical therapy, athletic training, and cancer treatment. Cleaning teeth in dental hygiene. Focused ultrasound sources may be used for cataract treatment by phacoemulsification. Additional physiological effects of low-intensity ultrasound have recently been discovered, e.g. the ability to stimulate bone-growth and its potential to disrupt the blood-brain barrier for drug delivery. Ultrasound is essential to the procedures of ultrasound-guided sclerotherapy and endovenous laser treatment for the non-surgical treatment of varicose veins. Ultrasound-assisted lipectomy is lipectomy assisted by ultrasound. Liposuction can also be assisted by ultrasound. Doppler ultrasound is being tested for use in aiding tissue plasminogen activator treatment in stroke sufferers in the procedure called ultrasound-enhanced systemic thrombolysis. Low intensity pulsed ultrasound is used for therapeutic tooth and bone regeneration. Ultrasound can also be used for elastography. This can be useful in medical diagnoses, as elasticity can discern healthy from unhealthy tissue for specific organs/growths. In some cases unhealthy tissue may have a lower system Q, meaning that the system acts more like a large heavy spring as compared to higher values of system Q (healthy tissue) that respond to higher forcing frequencies. Ultrasonic elastography is different from conventional ultrasound, as a transceiver (pair) and a transmitter are used instead of only a transceiver. One transducer (a single element {or array of elements} acts as both the transmitter and receiver to image the region of interest over time. The extra transmitter is a very low frequency transmitter, and perturbs the system so the unhealthy tissue oscillates at a low frequency and the healthy tissue does not. The transceiver, which operates at a high frequency (typically MHz) then measures the displacement of the unhealthy tissue (oscillating at a much lower frequency). The movement of the slowly oscillating tissue is used to determine the elasticity of the material, which can then be used to distinguish healthy tissue from the unhealthy tissue. Ultrasound has been shown to act synergistically with antibiotics in bacterial cell killing. Ultrasound has been postulated to allow thicker eukaryotic cell tissue cultures by promoting nutrient penetration.Scientific Article Ultrasound in the low MHz range in the form of standing waves is an emerging tool for contactless separation, concentration and manipulation of microparticles and biological cells. The basis is the acoustic radiation force, a non-linear effect which causes particles to be attracted to either the nodes or anti-nodes of the standing wave depending on the acoustic contrast factor, which is a function of the sound velocities and densities of the particle and of the medium in which the particle is immersed.
The ultrasound machine transmits high-frequency (1 to 5 megahertz) sound pulses into your body using a probe.
The sound waves travel into your body and hit a boundary between tissues (e.g. between fluid and soft tissue, soft tissue and bone).
Some of the sound waves get reflected back to the probe, while some travel on further until they reach another boundary and get reflected.
The reflected waves are picked up by the probe and relayed to the machine.
The machine calculates the distance from the probe to the tissue or organ (boundaries) using the speed of sound in tissue (5,005 ft/s or1,540 m/s) and the time of the each echo's return (usually on the order of millionths of a second).
The machine displays the distances and intensities of the echoes on the screen, forming a two dimensional image like the one shown belowUltrasound also has therapeutic applications, which can be highly beneficial when used with dosage precautions:
According to RadiologyInfo,ultrasounds are useful in the detection of pelvic abnormalities and can involve techniques known as abdominal (transabdominal) ultrasound, vaginal (transvaginal or endovaginal) ultrasound in women, and also rectal (transrectal) ultrasound in men. Treating benign and malignant tumors and other disorders via a process known as high intensity focused ultrasound (HIFU), also called focused ultrasound surgery (FUS). In this procedure, a generally lower frequencies than medical diagnostic ultrasound is used (250-2000 kHz), but significantly higher time-averaged intensities. The treatment is often guided by magnetic resonance imaging (MRI)—this is called Magnetic resonance-guided focused ultrasound (MRgFUS). Delivering chemotherapy to brain cancer cells and various drugs to other tissues is called acoustic targeted drug delivery (ATDD). These procedures generally use high frequency ultrasound (1-10 MHz) and a range of intensities (0-20 watts/cm2). The acoustic energy is focused on the tissue of interest to agitate its matrix and make it more permeable for therapeutic drugs.[17][18] Enhanced drug uptake using acoustic targeted drug delivery (ATDD).Therapeutic ultrasound, a technique that uses more powerful ultrasound sources to generate local heating in tissue: Used in occupational therapy, physical therapy, athletic training, and cancer treatment. Cleaning teeth in dental hygiene. Focused ultrasound sources may be used for cataract treatment by phacoemulsification. Additional physiological effects of low-intensity ultrasound have recently been discovered, e.g. the ability to stimulate bone-growth and its potential to disrupt the blood-brain barrier for drug delivery. Ultrasound is essential to the procedures of ultrasound-guided sclerotherapy and endovenous laser treatment for the non-surgical treatment of varicose veins. Ultrasound-assisted lipectomy is lipectomy assisted by ultrasound. Liposuction can also be assisted by ultrasound. Doppler ultrasound is being tested for use in aiding tissue plasminogen activator treatment in stroke sufferers in the procedure called ultrasound-enhanced systemic thrombolysis. Low intensity pulsed ultrasound is used for therapeutic tooth and bone regeneration. Ultrasound can also be used for elastography. This can be useful in medical diagnoses, as elasticity can discern healthy from unhealthy tissue for specific organs/growths. In some cases unhealthy tissue may have a lower system Q, meaning that the system acts more like a large heavy spring as compared to higher values of system Q (healthy tissue) that respond to higher forcing frequencies. Ultrasonic elastography is different from conventional ultrasound, as a transceiver (pair) and a transmitter are used instead of only a transceiver. One transducer (a single element {or array of elements} acts as both the transmitter and receiver to image the region of interest over time. The extra transmitter is a very low frequency transmitter, and perturbs the system so the unhealthy tissue oscillates at a low frequency and the healthy tissue does not. The transceiver, which operates at a high frequency (typically MHz) then measures the displacement of the unhealthy tissue (oscillating at a much lower frequency). The movement of the slowly oscillating tissue is used to determine the elasticity of the material, which can then be used to distinguish healthy tissue from the unhealthy tissue. Ultrasound has been shown to act synergistically with antibiotics in bacterial cell killing. Ultrasound has been postulated to allow thicker eukaryotic cell tissue cultures by promoting nutrient penetration.Scientific Article Ultrasound in the low MHz range in the form of standing waves is an emerging tool for contactless separation, concentration and manipulation of microparticles and biological cells. The basis is the acoustic radiation force, a non-linear effect which causes particles to be attracted to either the nodes or anti-nodes of the standing wave depending on the acoustic contrast factor, which is a function of the sound velocities and densities of the particle and of the medium in which the particle is immersed.
The manufacture of Ultrasound :
Almana Medical Imaging
Ebrahim Mohammed Almana & Bros. Co. Ltd.P.O. Box 3568
Alkhobar 31952Kingdom of Saudi ArabiaT: +966 3 8679400F: +966 3 8962421
Email : sales@almanamedical.com
Epoka Medic Mission A/S
Hjulmagervej 21DK-9490 Pandrup Denmark
Phone: +45 96 886 500Fax: +45 96 886 515
E-Mail: medic@epoka.com
GE Medical Systems Information Technologies
Marquette Hellige GmbHMunzinger Str. 3,79111 Freiburg, Germanytel: +49 761 45 43 0Fax: + 49 761 45 43 446
Innomed Medical
Zrt.HUNGARYBudapest 1146, Szabo Jozsef u. 12Tel.: +36 1 460 9200Fax: +36 1 460 9222
Email: innomed@innomed.hu
B-K Medical A/S
Sandtoften 9, DK-2820,Gentofte DenmarkTel: (45) 45 97 01 00Fax: (45) 45 97 01 99New address from 15.05.2002B-K Medical A/SMileparken 34 DK-2730Herlev DenmarkTel: (45) 4452 8100Fax: (45) 4452 8199
Josef Betschart AG
Seewenstrasse 3PO BOX 55CH-6440 BrunnenT +41 041 825 60 80F +41 041 825 60 85
Philips Medical Systems UK and Ireland
The ObservatoryP.O Box 263Castlefield Road ReigateSurrey - RH2 OFYTel: +44 (0) 1737 230 400Fax: +44 (0) 1737 230 401
RTI Electronics AB
Flojelbergsgatan 8C 431 37 MolndalSwedenTel: +46 31 746 3600Fax: +46 31 270 573
E-mail: info@rti-e.se
Varian Medical Systems, Inc.
Corporate Headquarters3100 Hansen WayPalo Alto, CA 94304-1038USA
Tel: 1.650.493.4000
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