X-ray computed tomography
From Citizendium, the Citizens' Compendium
X-ray computerized tomography is a type of computed tomography and is defined as "tomography using x-ray transmission and a computer algorithm to reconstruct the image."[1]
Classification
Newer types of X-ray computerized tomography
- Spiral CT. Spiral CT, also called helical CT is "computed tomography where there is continuous X-ray exposure to the patient while being transported in a spiral or helical pattern through the beam of irradiation. This provides improved three-dimensional contrast and spatial resolution compared to conventional computed tomography, where data is obtained and computed from individual sequential exposures".[2] Examples include computed tomographic pulmonary angiography for detecting pulmonary embolism, computed tomographic cardiac angiography for detecting coronary heart disease[3], and computed tomographic colonography (virtual colonoscopy).
- Cone CT is uses a cone or pyramid-shaped beam of radiation.[4]
Adverse effects
The risk associated with a CT scan (the increased risk of cancer associated with the radiation doses) is extremely low for any one person. However, given the increasing number of CT scans being obtained, the increasing exposure to radiation in the population may be a public health issue in the future. [5]
References
- ↑ Anonymous, (2009) X-ray computed tomography (English). Medical Subject Headings. U.S. National Library of Medicine.
- ↑ Anonymous, (2009) Tomography, Spiral Computed (English). Medical Subject Headings. U.S. National Library of Medicine.
- ↑ Stein PD, Yaekoub AY, Matta F, Sostman HD (August 2008). 64-slice CT for diagnosis of coronary artery disease: a systematic review. The American journal of medicine 121 (8): 715–25. DOI:10.1016/j.amjmed.2008.02.039. PMID 18691486.
- ↑ Anonymous, (2009) Cone-Beam Computed Tomography (English). Medical Subject Headings. U.S. National Library of Medicine.
- ↑ Brenner DJ, Hall EJ (2007). "Computed tomography--an increasing source of radiation exposure". N Engl J Med 357: 2277–84. DOI:10.1056/NEJMra072149. PMID 18046031.
