J Korean Soc Radiol.  2010 Feb;62(2):131-137. 10.3348/jksr.2010.62.2.131.

A Comparative Study of Image Quality and Radiation Dose with Changes in Tube Voltage and Current for a Digital Chest Radiography

• Park B
• Sung DW

• KMID: 2208950
• DOI: http://doi.org/10.3348/jksr.2010.62.2.131

Abstract

PURPOSE: High-voltage techniques applicable for analog radiographs are usually used in digital radiographs. We compared the image quality of the different exposure conditions to produce conditions of high image quality and low radiation dose.
MATERIALS AND METHODS
The tube voltage ranged from 70 to 133 kV, whereas the tube current ranged from 2 to 6.3 mAs. The digital radiograph images of a chest phantom were obtained at each setting. We measured the radiation doses of each condition, and counted the visible test objects. The numbers of objects for each condition were compared with the standards used at our institution.
RESULTS
The standard settings were set at 133 kVp and 2 or 4 mAs. Compared to the image quality at 133 kVp and 2 mAs, the radiation dose was lowest at a setting of 109 kVp and 2 mAs. Compared to the image quality of 133 kVp and 4 mAs, the radiation dose was lowest at 109 kVp and 4 mAs.
CONCLUSION
The results of our study suggest that radiation dose can be reduced without compromising image quality by a low-voltage technique in digitial radiography.

MeSH Terms

Radiation Dosage
Thorax

Figure

• 

  Fig. 1 Correlation of numbers of discs and radiation doses. Visible discs increase as the radiation dose increase.

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  Fig. 2 (A) 133kVp, 6.3 mAs. Radiation dose was the highest (241.2 µGy). On average, 49.17 discs were seen. (B) 70kVp, 2mAs. Radiation dose was lowest (16.9 µGy). On average, 32.38 discs were seen.

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  Fig. 3 (A) 109 kVp, 2mAs. Mean visible discs were 43.71 and not statistically different from that of in 133 kVp and 2mAs (B) (mean=45).

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  Fig. 4 (A) In condition of 109 kVp and 4 mAs, mean visible discs were 48.04 and not statistically different from that of 133 kVp, 4 mAs (B) (mean=49.13).

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