Comparative assessment of three image reconstruction techniques for image quality and radiation dose in patients undergoing abdominopelvic multidetector CT examinations.

OBJECTIVE To compare image quality and radiation dose of abdominal CT examinations reconstructed with three image reconstruction techniques. METHODS In this Institutional Review Board-approved study, contrast-enhanced (CE) abdominopelvic CT scans from 23 patients were reconstructed using filtered back projection (FBP), adaptive statistical iterative reconstruction (ASiR) and iterative reconstruction in image space (IRIS) and were reviewed by two blinded readers. Subjective (acceptability, sharpness, noise and artefacts) and objective (noise) measures of image quality were recorded for each image data set. Radiation doses in CT dose index (CTDI) dose-length product were also calculated for each examination type and compared. Imaging parameters were compared using the Wilcoxon signed rank test and a paired t-test. RESULTS All 69 CECT examinations were of diagnostic quality and similar for overall acceptability (mean grade for ASiR, 3.9±0.3; p=0.2 for Readers 1 and 2; IRIS, 3.9±0.4, p=0.2; FBP, 3.8±0.9). Objective noise was considerably lower with both iterative techniques (p<0.0001 and 0.0016 for ASiR and IRIS). Recorded mean radiation dose, i.e. CTDI(vol), was 24% and 10% less with ASiR (11.4±3.4 mGy; p<0.001) and IRIS (13.5±3.7 mGy; p=0.06), respectively, than with FBP: 15.0±3.5 mGy. CONCLUSION At the system parameters used in this study, abdominal CT scans reconstructed with ASiR and IRIS provide diagnostic images with reduced image noise and 10-24% lower radiation dose than FBP. ADVANCES IN KNOWLEDGE CT images reconstructed with FBP are frequently noisy on lowering the radiation dose. Newer iterative reconstruction techniques have different approaches to produce images with less noise; ASiR and IRIS provide diagnostic abdominal CT images with reduced image noise and radiation dose compared with FBP. This has been documented in this study.

[1]  M. V. van Leeuwen,et al.  A rational approach to dose reduction in CT: individualized scan protocols , 2001, European Radiology.

[2]  C. McCollough,et al.  CT dose reduction and dose management tools: overview of available options. , 2006, Radiographics : a review publication of the Radiological Society of North America, Inc.

[3]  L. Goldman.  Principles of CT and CT Technology* , 2007, Journal of Nuclear Medicine Technology.

[4]  Jean-Baptiste Thibault,et al.  A three-dimensional statistical approach to improved image quality for multislice helical CT. , 2007, Medical physics.

[5]  Rebecca S Lewis,et al.  Projected cancer risks from computed tomographic scans performed in the United States in 2007. , 2009, Archives of internal medicine.

[6]  Jun Zhao,et al.  A Filtered Backprojection Algorithm for Triple-Source Helical Cone-Beam CT , 2009, IEEE Transactions on Medical Imaging.

[7]  O. Linton,et al.  National Council on Radiation Protection and Measurements report shows substantial medical exposure increase. , 2009, Radiology.

[8]  T. Yoshizumi,et al.  Radiologic and nuclear medicine studies in the United States and worldwide: frequency, radiation dose, and comparison with other radiation sources--1950-2007. , 2009, Radiology.

[9]  Natalie N. Braun,et al.  Strategies for reducing radiation dose in CT. , 2009, Radiologic clinics of North America.

[10]  J. Remy,et al.  Chest computed tomography using iterative reconstruction vs filtered back projection (Part 2): image quality of low-dose CT examinations in 80 patients , 2011, European Radiology.

[11]  Alvin C. Silva,et al.  Innovations in CT dose reduction strategy: application of the adaptive statistical iterative reconstruction algorithm. , 2010, AJR. American journal of roentgenology.

[12]  Alexander Katsevich,et al.  Fast Exact/Quasi-Exact FBP Algorithms for Triple-Source Helical Cone-Beam CT , 2010, IEEE Transactions on Medical Imaging.

[13]  E. Samei,et al.  Low-tube-voltage, high-tube-current multidetector abdominal CT: improved image quality and decreased radiation dose with adaptive statistical iterative reconstruction algorithm--initial clinical experience. , 2010, Radiology.

[14]  D. Sahani,et al.  Reducing Abdominal CT Radiation Dose With Adaptive Statistical Iterative Reconstruction Technique , 2010, Investigative radiology.

[15]  Alvin C. Silva,et al.  Reducing the radiation dose for CT colonography using adaptive statistical iterative reconstruction: A pilot study. , 2010, AJR. American journal of roentgenology.

[16]  J. Remy,et al.  Chest computed tomography using iterative reconstruction vs filtered back projection (Part 1): evaluation of image noise reduction in 32 patients , 2011, European Radiology.

[17]  S. Achenbach,et al.  Iterative reconstruction in image space (IRIS) in cardiac computed tomography: initial experience , 2011, The International Journal of Cardiovascular Imaging.

[18]  R. Raupach,et al.  Iterative reconstruction algorithm for abdominal multidetector CT at different tube voltages: assessment of diagnostic accuracy, image quality, and radiation dose in a phantom study. , 2011, Radiology.

[19]  S. Park,et al.  A prospective comparison of standard-dose CT enterography and 50% reduced-dose CT enterography with and without noise reduction for evaluating Crohn disease. , 2011, AJR. American journal of roentgenology.

[20]  H. Krumholz,et al.  National trends in use of computed tomography in the emergency department. , 2011, Annals of emergency medicine.

[21]  C. Fink,et al.  Coronary CT angiography: image quality, diagnostic accuracy, and potential for radiation dose reduction using a novel iterative image reconstruction technique—comparison with traditional filtered back projection , 2011, European Radiology.

[22]  W. Huda,et al.  CT effective dose per dose length product using ICRP 103 weighting factors. , 2011, Medical physics.

[23]  T. Flohr,et al.  Iterative image reconstruction techniques: Applications for cardiac CT. , 2011, Journal of cardiovascular computed tomography.

[24]  Naveen M. Kulkarni,et al.  Low-dose MDCT and CT enterography of patients with Crohn disease: feasibility of adaptive statistical iterative reconstruction. , 2011, AJR. American journal of roentgenology.

[25]  Christian Stahl,et al.  Dose Reduction in Abdominal Computed Tomography: Intraindividual Comparison of Image Quality of Full-Dose Standard and Half-Dose Iterative Reconstructions With Dual-Source Computed Tomography , 2011, Investigative radiology.

[26]  H. Alkadhi,et al.  Raw data-based iterative reconstruction in body CTA: evaluation of radiation dose saving potential , 2011, European Radiology.

[27]  C Ghetti,et al.  CT iterative reconstruction in image space: a phantom study. , 2012, Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics.

[28]  D. Sahani,et al.  Impact of iterative reconstruction on image quality and radiation dose in multidetector CT of large body size adults , 2012, European Radiology.