Ultrasound+imaging

toc =Definition= Ultasound Image or Sonagraphy is a high frequency sound wave used to produce a picture of the soft organs inside the body. Its 20,000 or more vibrations per second creates a real time clear picture. Being in real time images ultasound allows you to see the flow of blood and also the way organs move and are working inside the body. This helps doctors to diagnose and treat a patient instantly. Unlike an x-ray which exposes the body to radiation the Ultrasonic image is safe and noninvasive to everyone. Sonograms, however, meet their limit with bones due to their high density and with air-filled structures. Therefore, ultrasound images only allow you to see soft tissue organs such as kidneys, liver, heart, lungs, breast, womb, etc.

//(Sonogram at 22 weeks, courtesy of [|Flickr.com user Captain Warren])//

=Medical Uses= The Ultrasound examination is commonly used in internal medicine. This is the area of medicine that pertains to the soft tissue organs such as the heart, kidneys, lungs gallbladder, etc. Because of ultrasounds ability to get clear 3-D or even 4-D images, this allows doctors to look and diagnose the conditions of the bodies organs and follow up on organs which are damaged by illness. Ultrasound is also used to clean teeth, generate regional heat in biological tissue, treat cysts and tumors, and can even be used to break up kidney stones. Although ultrasounds are most commonly used in the medical fields of Gynecology and Obstetrics to make a diagnosis, it can also be seen in different medical fields such as Cardiology and even Echocardiograms or cardiac sonograms. These are used to create images of the heart using two dimensional or even three-dimensional ultrasound to display the heart in real-time imaging. Several things such as the strength of the heart valves and the velocity of blood flow can be seen through these image processors. Also, defects such as a heart attack and tumors can be seen.

//(Sonogram of a liver that had metastases, courtesy of [|Flickr.com user robhengxr]//)

=How it works= Sonograms or ultrasounds, work by first producing a sound wave, receiving the echoes back, and then interpreting them. The sound wave is produced by a "piezoelectric transducer" within a probe. This sends pulsating waves into the body part wished to be viewed or treated. These sound waves sent are then vibrated back into the transducer, allowing the scanner to have enough information to produce the image. To form the image, it must determine three things: the strength of the echo, the direction of the echo and how long it took to transmit and receive the echo. The image is then created from the time it took to transmit and receive sound waves. For example, when an ultrasound is taken of a mother fetus, an image of the unborn infant is created because of the sound waves reverberating off of its body. With the use of the sonograms, a doctor can determine the sex of the baby, analyze if any defects or abnormalities are present and ultrasound can also be used to monitor the growth of the fetus, from the images the ultrasound produces. (//Right: Sonogram Machine, courtesy of [|Flickr.com user freeformkatia]// //Left:Sonogram of a human heart, courtesy of [|Flickr.com user Sam Felder])// =History of Ultrasounds= During the first uses of sonograms in medical practice, many had primarily used them for treatments, rather than for diagnostics because of its destructive abilities.In later years people began to use and recognize sonograms as a diagnostic tool and several doctors then began experimenting with sonography in medical diagnosis. Sonograms first started out as A-Mode, which detects fetal heart beat, and B-Mode, which detects the gestational sac. Ultrasounds then progressed to using a scan converter which removed calipers, scaled the picture and then applied the picture on-screen. This then created a new imaging process called gray scale. Since gray-scaling, it has advanced to three-dimensional and even four-dimensional ultrasound imaging. Although the history can sometimes be confusing, it is known it was first introduced in 1955. =Links= http://www.mayoclinic.com/health/ultrasound/PR00053 http://www.radiologyinfo.org/en/info.cfm?pg=genus http://brighamrad.harvard.edu/education/online/US/ http://www.ob-ultrasound.net/

=Sources= [|History of Ultrasounds in Obstetrics] [|Wikipedia: Ultrasonography] [|FLICKR.COM] [|Mayoclinic.com: Ultrasound]