Ultrasound, AKA diagnostic sonography, ultrasonography and medical ultrasound, is a diagnostic imaging technique based on the application of ultrasound waves. It is a simple, painless and non-invasive medical procedure, with no exposure to radiation, performed for both diagnostic and therapeutic purposes. It is produced after the transducer of an ultrasound machine sends sound waves to the body area to be examined which are reflected by the tissues/organs and captured by a computer in the ultrasound scanner, which uses them to create an image. Ultrasound is used to see the internal tissues and organs of the body including tendons, joints, muscles, blood vessels and solid organs like the kidneys, spleen and liver.
Compared to other methods of medical imaging, ultrasound has several advantages. It is portable and can be brought to the bedside, has a significantly lower cost, does not use harmful ionizing radiation, has no side effects, is safe to use during pregnancy, and provides images in real-time, which makes it useful in some medical procedures like central venous access placement and biopsies.
Additional ultrasound techniques include biplanar ultrasound, omniplane ultrasound, Doppler ultrasonography (vascular, echocardiography, transcranial and fetal), contrast ultrasonography, molecular ultrasonography, elastography (ultrasound elasticity imaging), interventional ultrasonography and compression ultrasonography.