- 作者：Sungwon Lee ; Seung Eun Jung ; Sung Eun Rha ; Jae Young Byun
- 关键词：Kilovoltage ; CT urography ; Radiation dose ; 100 ; kVp
- 刊名：European Journal of Radiology
- 出版年：2012
- 出版时间：August, 2012
- 年：2012
- 卷：81
- 期：8
- 页码：e830-e834
- 全文大小：389 K
Objective
To compare 128-slice multidetector computed tomography (MDCT) at 100 kVp and 120 kVp for image quality and radiation dose.Materials and methods
Our study had approval of our institutional review board. We retrospectively selected 25 patients who underwent CT urography for the evaluation of hematuria. The CT scans were taken with 128-slice MDCT, with three phases (precontrast, nephrographic, and excretory), using an automatic tube current modulation with reference tube level of 180 mA s and tube voltages of either 100 kVp (n = 14, mean age 26.71) or 120 kVp (n = 11, mean age 25.54). The signal-to-noise-ratio (SNR) and contrast-to-noise-ratio (CNR) of the urinary tract, the subjective image quality of the urinary tract evaluated with a five point scale by two radiologists and the effective dose calculated on the basis of dose-length-product (DLP) and volume-CT-dose-index (CTDIvol) were compared between the groups with Student's t test or Mann-Whitney U test.
Results
There was no significant difference in the SNR (p = 0.358), CNR (p = 0.303) and the subjective image quality (p = 0.486) between the two protocols. The mean CTDIvol, DLP and the effective dose in the 100 kVp protocol were significantly lower than the 120 kVp protocol (p = 0.000, 0.000).
Conclusion
CT urography using 100 kVp protocol resulted in reduction of radiation dose without loss of objective or subjective image quality.