Computed Tomography: Are We Aware of Radiation Risks in Computed Tomography?

Abstract

Today, people are constantly exposed to varying radiation. While some people exposed to little radiation, others exposed to a lot. In Turkey 73 percent of the radiation sourced are used in medical sector while rest of them are used in industrial or other activities. Radiological examinations have an indispensable role in the diagnosis and treatment of disease, although radiation has been proven to have adverse biological effects on living organisms.

Computed Tomography (CT) is valuable imaging tool and plays a important role in the evaluation of many diseases. CT scan, is a special x-ray that scans an area one layer (slice) at a time. It is therefore imperative to understand how we missed the problem of excessive radiation so we can both remedy it and prevent unnecessary exposure with newer technologies such as computed radiography. The ALARA (as low as reasonably achievable) principle requires that patients should not be exposed to any radiation that is not required for producing an image of diagnostic quality. For computed tomography, dose reduction should be optimised by the adjustment of scan parameters. Some of this parameters are mA, kVp, and pitch and these can change according to patient weight or age, region, scanned and study indication.

Each CT exam must be appropriate for the individual patient. Justification is a shared responsibility between requesting clinicians and radiologists. Increase awareness for the need to decrease radiation dose to patient during CT scanning.

Keywords

• Computed Tomography, radiation, the ALARA

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