Usability Evaluation of Applied Low-dose CT When Examining Urinary Calculus Using Computed Tomography

컴퓨터 단층촬영을 이용한 요로결석 검사에서 저선량 CT의 적용에 대한 유용성 평가

  • 김현진 (가야대학교 방사선학과) ;
  • 지태정 (가야대학교 방사선학과)
  • Received : 2017.02.02
  • Accepted : 2017.03.06
  • Published : 2017.06.28


The aim of this study was to evaluate the usability of applied Low dose Computed Tomography(LDCT) protocol in examining urinary calculus using computed tomography. The subjects of this study were urological patients who visited a medical institution located in Busan from June to December 2016 and the protocol used in this study was Adaptive Statistical Iterative Reconstruction: low-dose CT with 50% Adaptive Statistical Iterative Reconstruction (ASIR). As results of quantitative analysis, the mean pixel value and standard deviation within kidney region of image(ROI)of the axial image were $26.21{\pm}7.08$ in abdomen CT pre scan and $20.03{\pm}8.16$ in low-dose CT. Also the mean pixel value and standard deviation within kidney ROI of the coronal image were $22.07{\pm}7.35$ in abdomen CT pre scan and $21.67{\pm}6.11$ in low dose CT. The results of qualitative analysis showed that four raters' mean values of observed kidney artifacts were $19.14{\pm}0.36$ when using abdomen CT protocol and $19.17{\pm}0.43$ in low-dose CT, and the mean value of resolution and contrast was $19.35{\pm}0.70$ when using abdomen CT protocol and $19.29{\pm}0.58$ in low-dose CT. Also the results of a exposure dose analysis showed that the mean values of CTDIvol and DLP in abdomen CT pre scan were 18.02 mGy and $887.51mGy{\cdot}cm$ respectively and the mean values of CTDIvol and DLP when using low-dose CT protocol were 7.412 mGy and $361.22mGy{\cdot}cm$ respectively. The resulting dose reduction rate was 58.82% and 59.29%, respectively.


Computed Tomography Dose Index;Low Does CTl;Dose Report;Urinary Calculus


  1. G. C. Curhan, "Epidemiology of stone disease," Urologic Clinics of North America, Vol. 34, Issue.3, pp. 287-293, 2007.
  2. S. Yilmaz, T. Sindel, G. Arslan, C. Ozkaynak, K. Karaali, A. Kabaalioglu, and E. Luleci, "Renal colic: comparison of spiral CT, US and IVU in the detection of ureteral calculi," European radiology, Vol. 8, Issue.2, pp. 212-217, 1998.
  3. B. S. Kim, S. N. Kung, H. C. Kim, W. C. Hwang, I. S. Lee, I. K. Hwang, H. C. Kim, S. H. Bae, S. K. Lee, and S. H. Lee, "Usefulness of Unenhanced Helical CT in Patients with Suspected Ureteral Colic," Journal of the Korean Society of Radiology, Vol. 47, No. 1, pp. 61-67, 2002.
  4. B. S. John, U. Patel, and K. Anson, "What radiation exposure can a patient expect during a single stone episode?," Journal of endourology, Vol. 22, No. 3, pp. 419-422, 2008.
  5. D. J. Brenner and E. J. Hall, "Computed tomography an 14 increasing source of radiation exposure," The New England ournal of medicine, Vol. 357, No. 22, pp. 2277-2284, 2007.
  6. M. Lopez and B. Hoppe, "History, epidemiology and regional diversities of urolithiasis," Pediatric nephrology, Vol. 25, No. 1, pp. 49-59, 2010.
  7. V. P. Sukumar, J. Collingwood, T. Crawley, D. Schofield, J. Henson, K. Lakin, D. Connolly, and J. Giles, "Low dose computed tomography in suspected acute renal colic," Clin Radiol, Vol. 56, No. 11, pp. 873-876, 2001
  8. P. Rogalla, C. Kluner, and M. Taupitz, "Ultra-low dose CT to search for stones in kidneys andcollecting system [in German]," AktuelleUrol, Vol. 35, No. 4, pp. 307-309, 2004.
  9. R. Bartoletti, T. Cai, N. Mondaini, F. Melone, F. Travaglini, M. Carini, and M. Rizzo, "Epidemiology and risk factors in urolithiasis," Urologia Internationalis, Vol. 79, Suppl.1, 2007.
  10. National Research Council, Health Risks from Exposure to Low Levels of Ionizing Radiation: BEIR VII Phase 2, The National Academies Press, 2006.