Diagnostic ultrasound and radiography are both imaging modalities used for diagnosis. Each modality is better than the other for certain things, and they are often used in conjunction with one another to diagnose some conditions.
Function
Diagnostic ultrasound uses sounds waves at frequencies of about 2 to 16 megahertz. Radiography uses radiation and records x-ray photon absorption by the body's tissues.
Specializations
Ultrasound is the preferred modality for assessing pregnancies. It is also the ideal method of imaging for thyroid masses, scrotal masses and gallstones. Radiography is most commonly used for imaging bones (x-ray). It is also quite useful for detecting bowel obstructions.
Combined Imaging
Both ultrasound and radiography are useful for looking for kidney stones. They may be used together to assess the whole urinary tract. Ultrasound can image the kidneys well, but cannot see the ureters. Radiography is used to determine if a stone is in one of the ureters. Sound waves and radiation see things differently, which is why they are sometimes used together, as is the case with breast imaging.
Warning
Technicians of both imaging modalities follow the principle of ALARA--As Low As Reasonably Possible. Ultrasound currently has no known negative effects, but health care professionals use it conservatively to prevent any unknown effects. Radiography uses radiation, which has been shown to cause cancer at certain levels. Health care professionals strive to use as little radiation as possible. The levels of ultrasound and radiation used for diagnostic imaging are generally safe.
Potential
Research is currently being done to improve ultrasound, especially in the areas of reconstructions and 3D imaging. Radiography has advanced greatly, especially with the offshoot of computed tomography (CT). 3D reconstructions are currently used with CT. Fluoroscopy is a form of radiography that allows for the visualization of vascular structures and the bowel using intravenous and oral contrast, respectively.
Tags: both imaging, both imaging modalities, care professionals, Diagnostic ultrasound, imaging modalities