X-rays and Ultrasound:
X-rays and ultrasound are two different modalities used for different things, so an ultrasound can do some things an X ray cannot, and vice versa, and so this makes them very difficult to directly compare. Ultrasound:
Above: An ultrasound machine.
Ultrasound is the use of energy generated by sound waves of 20,000 or more vibrations per second. Ultrasounds are generated by a device called a transducer. Bearing in mind that sound is a mechanical energy, the transducer uses a crystal driver to concert electrical energy into mechanical energy. The crystal can change shape via electrical stimulation, as the change in shape squeezes the crystal, causing it to generate an electrical signal. The transducer is used to send out a signal and then listen out for the echo, which generates the image seen on ultrasounds. Humans can hear 20 cycles per second, (cps or Hertz) to 20,000 cps. Most ultrasonic transducers work in an excess of 1,000,000!
Ultrasounds are most commonly used to show different fluid densities and things that are closer to the surface. As the ultrasound images have very low resolution most people have difficulty reading them, and only people with skills in the field can decipher the images. As ultrasound cannot penetrate very deeply thus obese patients and objects with a thick density cannot be viewed easily. As stated in the name, ultrasound makes use of extremely small sound waves to penetrate objects. Ultrasound was discovered by two researchers, namely Dr. Karl Theodore Dussik of Australia and Prof. Ian Donald of Scotland. Dr. Karl Theodore initially published his first book on the subject (medical ultrasonic’s) in 1942 based on his research which he did on the transmission of ultrasound within the brain. Prof. Ian Donald then developed the practical application of ultrasound in the 1950’s. Ultrasound is very useful as a medical tool and its uses grow by day, some of these uses include: - Confirmation of a pregnancy and...
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