Adaptive Iterative Dose Reduction Algorithm in CT: Effect on Image Quality Compared with Filtered Back Projection in Body Phantoms of Different Sizes

다국어 초록 (Multilingual Abstract)

Objective: To evaluate the impact of the adaptive iterative dose reduction (AIDR) three-dimensional (3D) algorithm in CT on noise reduction and the image quality compared to the filtered back projection (FBP) algorithm and to compare the effectiveness of AIDR 3D on noise reduction according to the body habitus using phantoms with different sizes.
Materials and Methods: Three different-sized phantoms with diameters of 24 cm, 30 cm, and 40 cm were built up using the American College of Radiology CT accreditation phantom and layers of pork belly fat. Each phantom was scanned eight times using different mAs. Images were reconstructed using the FBP and three different strengths of the AIDR 3D. Theimage noise, the contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) of the phantom were assessed. Two radiologists assessed the image quality of the 4 image sets in consensus. The effectiveness of AIDR 3D on noise reduction compared with FBP were also compared according to the phantom sizes.
Results: Adaptive iterative dose reduction 3D significantly reduced the image noise compared with FBP and enhanced the SNR and CNR (p < 0.05) with improved image quality (p < 0.05). When a stronger reconstruction algorithm was used, greater increase of SNR and CNR as well as noise reduction was achieved (p < 0.05). The noise reduction effect of AIDR 3Dwas significantly greater in the 40-cm phantom than in the 24-cm or 30-cm phantoms (p < 0.05).
Conclusion: The AIDR 3D algorithm is effective to reduce the image noise as well as to improve the image-quality parameters compared by FBP algorithm, and its effectiveness may increase as the phantom size increases.

참고문헌 (Reference)

1 Voress M, "The increasing use of CT and its risks" 79 : 186-190, 2007

2 Tatsugami F, "The effect of adaptive iterative dose reduction on image quality in 320-detector row CT coronary angiography" 85 : e378-e382, 2012

3 Kalender WA, "Technical approaches to the optimisation of CT" 24 : 71-79, 2008

4 McCollough CH, "Strategies for reducing radiation dose in CT" 47 : 27-40, 2009

5 Halliburton SS, "SCCT guidelines on radiation dose and doseoptimization strategies in cardiovascular CT" 5 : 198-224, 2011

6 Koshy S, "Review of radiation reduction strategies in clinical cardiovascular imaging" 20 : 139-144, 2012

7 Smith-Bindman R, "Radiation dose associated with common computed tomography examinations and the associated lifetime attributable risk of cancer" 169 : 2078-2086, 2009

8 황혜전, "Radiation Dose Reduction of Chest CT with Iterative Reconstruction in Image Space - Part I: Studies on Image Quality Using Dual Source CT" 대한영상의학회 13 (13): 711-719, 2012

9 황혜전, "Radiation Dose Reduction of Chest CT with Iterative Reconstruction in Image Space - Part II: Assessment of Radiologists’ Preferences Using Dual Source CT" 대한영상의학회 13 (13): 720-727, 2012

10 Berrington de González A, "Projected cancer risks from computed tomographic scans performed in the United States in 2007" 169 : 2071-2077, 2009

11 Gupta AK, "Optimization of eight-element multi-detector row helical CT technology for evaluation of the abdomen" 227 : 739-745, 2003

12 Yu L, "Optimal tube potential for radiation dose reduction in pediatric CT: principles, clinical implementations, and pitfalls" 31 : 835-848, 2011

13 Yamada Y, "Model-based iterative reconstruction technique for ultralow-dose computed tomography of the lung: a pilot study" 47 : 482-489, 2012

14 Mahesh M, "Medical radiation exposure with focus on CT" 25 : 69-74, 2010

15 Hara AK, "Iterative reconstruction technique for reducing body radiation dose at CT: feasibility study" 193 : 764-771, 2009

16 Martinsen AC, "Iterative reconstruction reduces abdominal CT dose" 81 : 1483-1487, 2012

17 Xu J, "Is iterative reconstruction ready for MDCT?" 6 : 274-276, 2009

18 Silva AC, "Innovations in CT dose reduction strategy: application of the adaptive statistical iterative reconstruction algorithm" 194 : 191-199, 2010

19 McCollough CH, "In defense of body CT" 193 : 28-39, 2009

20 Kanal KM, "Impact of operator-selected image noise index and reconstruction slice thickness on patient radiation dose in 64-MDCT" 189 : 219-225, 2007

21 Desai GS, "Impact of iterative reconstruction on image quality and radiation dose in multidetector CT of large body size adults" 22 : 1631-1640, 2012

22 Utsunomiya D, "Effect of hybrid iterative reconstruction technique on quantitative and qualitative image analysis at 256-slice prospective gating cardiac CT" 22 : 1287-1294, 2012

23 Prakash P, "Diffuse lung disease: CT of the chest with adaptive statistical iterative reconstruction technique" 256 : 261-269, 2010

24 Kalra MK, "Detection and characterization of lesions on low-radiationdose abdominal CT images postprocessed with noise reduction filters" 232 : 791-797, 2004

25 Brenner DJ, "Computed tomography--an increasing source of radiation exposure" 357 : 2277-2284, 2007

26 Pontana F, "Chest computed tomography using iterative reconstruction vs filtered back projection (Part 2): image quality of low-dose CT examinations in 80 patients" 21 : 636-643, 2011

27 Pontana F, "Chest computed tomography using iterative reconstruction vs filtered back projection (Part 1): evaluation of image noise reduction in 32 patients" 21 : 627-635, 2011

28 Rogalla P, "CT technology overview:64-slice and beyond" 47 : 1-11, 2009

29 Gervaise A, "CT image quality improvement using Adaptive Iterative Dose Reduction with wide-volume acquisition on 320-detector CT" 22 : 295-301, 2012

30 구현우, "CT Radiation Dose Optimization and Estimation: an Update for Radiologists" 대한영상의학회 13 (13): 1-11, 2012

31 Marin D, "Body CT:technical advances for improving safety" 197 : 33-41, 2011

32 Mitsumori LM, "Adaptive statistical iterative reconstruction versus filtered back projection in the same patient: 64 channel liver CT image quality and patient radiation dose" 22 : 138-143, 2012

33 Sagara Y, "Abdominal CT: comparison of low-dose CT with adaptive statistical iterative reconstruction and routine-dose CT with filtered back projection in 53 patients" 195 : 713-719, 2010

34 Thibault JB, "A threedimensional statistical approach to improved image quality for multislice helical CT" 34 : 4526-4544, 2007