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Observer performance for adaptive, image-based denoising and filtered back projection compared to scanner-based iterative reconstruction for lower dose CT enterography

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Abstract

Purpose

The purpose of this study was to compare observer performance for detection of intestinal inflammation for low-dose CT enterography (LD-CTE) using scanner-based iterative reconstruction (IR) vs. vendor-independent, adaptive image-based noise reduction (ANLM) or filtered back projection (FBP).

Methods

Sixty-two LD-CTE exams were performed. LD-CTE images were reconstructed using IR, ANLM, and FBP. Three readers, blinded to image type, marked intestinal inflammation directly on patient images using a specialized workstation over three sessions, interpreting one image type/patient/session. Reference standard was created by a gastroenterologist and radiologist, who reviewed all available data including dismissal Gastroenterology records, and who marked all inflamed bowel segments on the same workstation. Reader and reference localizations were then compared. Non-inferiority was tested using Jackknife free-response ROC (JAFROC) figures of merit (FOM) for ANLM and FBP compared to IR. Patient-level analyses for the presence or absence of inflammation were also conducted.

Results

There were 46 inflamed bowel segments in 24/62 patients (CTDIvol interquartile range 6.9–10.1 mGy). JAFROC FOM for ANLM and FBP were 0.84 (95% CI 0.75–0.92) and 0.84 (95% CI 0.75–0.92), and were statistically non-inferior to IR (FOM 0.84; 95% CI 0.76–0.93). Patient-level pooled confidence intervals for sensitivity widely overlapped, as did specificities. Image quality was rated as better with IR and AMLM compared to FBP (p < 0.0001), with no difference in reading times (p = 0.89).

Conclusions

Vendor-independent adaptive image-based noise reduction and FBP provided observer performance that was non-inferior to scanner-based IR methods. Adaptive image-based noise reduction maintained or improved upon image quality ratings compared to FBP when performing CTE at lower dose levels.

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References

  1. American College of Radiology. ACR Appropriateness Criteria. (http://www.acrorg/quality-safety/appropriateness-criteria) Accessed 25 Mar 2013, 2014

  2. Al-Hawary MM, Kaza RK, Platt JF (2013) CT enterography: concepts and advances in Crohn’s disease imaging. Radiol Clin North Am 51:1–16

    Article  PubMed  Google Scholar 

  3. Bruining DH, Siddiki HA, Fletcher JG, et al. (2012) Benefit of computed tomography enterography in Crohn’s disease: effects on patient management and physician level of confidence. Inflamm Bowel Dis 18:219–225

    Article  PubMed  Google Scholar 

  4. Higgins PD, Caoili E, Zimmermann M, et al. (2007) Computed tomographic enterography adds information to clinical management in small bowel Crohn’s disease. Inflamm Bowel Dis 13:262–268

    Article  PubMed  Google Scholar 

  5. Kerner C, Carey K, Mills AM, et al. (2012) Use of abdominopelvic computed tomography in emergency departments and rates of urgent diagnoses in Crohn’s disease. Clin Gastroenterol Hepatol 10:52–57

    Article  PubMed Central  PubMed  Google Scholar 

  6. Israeli E, Ying S, Henderson B, et al. (2013) The impact of abdominal computed tomography in a tertiary referral centre emergency department on the management of patients with inflammatory bowel disease. Aliment Pharmacol Ther 38:513–521

    Article  CAS  PubMed  Google Scholar 

  7. Guimaraes LS, Fidler JL, Fletcher JG, et al. (2010) Assessment of appropriateness of indications for CT enterography in younger patients. Inflamm Bowel Dis 16:226–232

    Article  PubMed  Google Scholar 

  8. Fletcher JG (2008) CT enterography technique: theme and variations. Abdom Imaging 34:283–288

    Article  Google Scholar 

  9. Allen BC, Baker ME, Einstein DM, et al. (2010) Effect of altering automatic exposure control settings and quality reference mAs on radiation dose, image quality, and diagnostic efficacy in MDCT enterography of active inflammatory Crohn’s disease. Am J Roentgenol 195:89–100

    Article  Google Scholar 

  10. Kambadakone AR, Prakash P, Hahn PF, Sahani DV (2010) Low-dose CT examinations in Crohn’s disease: impact on image quality, diagnostic performance, and radiation dose. Am J Roentgenol 195:78–88

    Article  Google Scholar 

  11. Kaza RK, Platt JF, Al-Hawary MM, et al. (2012) CT enterography at 80 kVp with adaptive statistical iterative reconstruction versus at 120 kVp with standard reconstruction: image quality, diagnostic adequacy, and dose reduction. Am J Roentgenol 198:1084–1092

    Article  Google Scholar 

  12. Del Gaizo AJ, Fletcher JG, Yu L, et al. (2013) Reducing radiation dose in CT enterography. Radiographics 33:1109–1124

    Article  PubMed  Google Scholar 

  13. Sagara Y, Hara AK, Pavlicek W, et al. (2010) Abdominal CT: comparison of low-dose CT with adaptive statistical iterative reconstruction and routine-dose CT with filtered back projection in 53 patients. Am J Roentgenol 195:713–719

    Article  Google Scholar 

  14. Prakash P, Kalra MK, Kambadakone AK, et al. (2010) Reducing abdominal CT radiation dose with adaptive statistical iterative reconstruction technique. Invest Radiol 45:202–210

    Article  PubMed  Google Scholar 

  15. Lee SJ, Park SH, Kim AY, et al. (2011) A prospective comparison of standard-dose CT enterography and 50% reduced-dose CT enterography with and without noise reduction for evaluating Crohn disease. Am J Roentgenol 197:50–57

    Article  Google Scholar 

  16. Baker ME, Dong F, Primak A, et al. (2012) Contrast-to-noise ratio and low-contrast object resolution on full- and low-dose MDCT: SAFIRE versus filtered back projection in a low-contrast object phantom and in the liver. Am J Roentgenol 199:8–18

    Article  Google Scholar 

  17. Goenka AH, Herts BR, Obuchowski NA, et al. (2014) Effect of reduced radiation exposure and iterative reconstruction on detection of low-contrast low-attenuation lesions in an anthropomorphic liver phantom: an 18-reader study. Radiology 272:154–163

    Article  PubMed  Google Scholar 

  18. Ehman EC, Yu L, Manduca A, et al. (2014) Methods for clinical evaluation of noise reduction techniques in abdominopelvic CT. Radiographics 34:849–862

    Article  PubMed  Google Scholar 

  19. Borgen L, Kalra MK, Laerum F, et al. (2012) Application of adaptive non-linear 2D and 3D postprocessing filters for reduced dose abdominal CT. Acta Radiol 53:335–342

    Article  PubMed  Google Scholar 

  20. De Geer J, Sandborg M, Smedby O, Persson A (2011) The efficacy of 2D, non-linear noise reduction filtering in cardiac imaging: a pilot study. Acta Radiol 52:716–722

    Article  PubMed  Google Scholar 

  21. Lubner MG, Pickhardt PJ, Kim DH, et al. (2015) Prospective evaluation of prior image constrained compressed sensing (PICCS) algorithm in abdominal CT: a comparison of reduced dose with standard dose imaging. Abdom Imaging 40:207–221

    Article  PubMed  Google Scholar 

  22. Nishimaru E, Ichikawa K, Okita I, et al. (2010) Development of a noise reduction filter algorithm for pediatric body images in multidetector CT. J Digit Imaging 23:806–818

    Article  PubMed Central  PubMed  Google Scholar 

  23. Li Z, Yu L, Trzasko JD, et al. (2014) Adaptive nonlocal means filtering based on local noise level for CT denoising. Med Phys 41:011908

    Article  PubMed  Google Scholar 

  24. Yu L, Fletcher JG, Grant KL, et al. (2013) Automatic selection of tube potential for radiation dose reduction in vascular and contrast-enhanced abdominopelvic CT. Am J Roentgenol 201:W297–W306

    Article  Google Scholar 

  25. Faubion WA Jr, Fletcher JG, O’Byrne S, et al. (2013) EMerging BiomARKers in Inflammatory Bowel Disease (EMBARK) study identifies fecal calprotectin, serum MMP9, and serum IL-22 as a novel combination of biomarkers for Crohn’s disease activity: role of cross-sectional imaging. Am J Gastroentero 108:1891–1900

    Article  CAS  Google Scholar 

  26. European Commission. European guidelines on quality criteria for computed tomography (EUR 16262 EN). In. Luxembourg: European Commission & The Office For Official Publications of the European Communities, 2000

  27. Murray G (2001) Points to consider on switching between superiority and non-inferiority. Clin Pharmacol 52:223–228

    Google Scholar 

  28. Chakraborty DP (1989) Maximum likelihood analysis of free-response receiver operating characteristic (FROC) data. Med Phys 16:561–568

    Article  CAS  PubMed  Google Scholar 

  29. Chakraborty DP, Berbaum KS (2004) Observer studies involving detection and localization: modeling, analysis, and validation. Med Phys 31:2313–2330

    Article  PubMed  Google Scholar 

  30. Dorfman DD, Berbaum KS, Metz CE (1992) Receiver operating characteristic rating analysis. Generalization to the population of readers and patients with the jackknife method. Invest Radiol 27:723–731

    Article  CAS  PubMed  Google Scholar 

  31. Samuel S, Bruining DH, Loftus EV, et al. (2012) Endoscopic skipping of the distal terminal ileum in Crohn’s disease can lead to negative results from ileocolonoscopy. Clin Gastroenterol Hepatol 10:1253–1259

    Article  PubMed  Google Scholar 

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Acknowledgments

Authors wish to acknowledge several key individuals for their contribution to this work. We thank Zhoubo Li and Dr. Armando Manduca for their development of the adaptive, image-based denoising method studied in this work, along with Drs. Dan Blezek and Brad Erickson, who were instrumental in adapting this method for implementation on a computer server that could be used in clinical practice. David Lake was extremely helpful in pilot work designed to refine the ANLM algorithm for clinical use. Kurt Augustine largely wrote the software, which the specialized computer workstations used for recording and matching of reader and reference markings. Sally Reinhart was invaluable in her assistance with manuscript preparation. This grant was supported by a Mayo Clinic Discovery and Translation Award.

Conflict of interest

A provisional patent application explaining the adaptive, image-based denoising method examined in this manuscript has been filed. Drs. Fletcher and McCollough are co-authors of the patent application. The other authors have no conflict of interest.

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Correspondence to Joel G. Fletcher.

Appendix: image quality assessment performed by radiologist readers

Appendix: image quality assessment performed by radiologist readers

Image quality criteria were performed after observer interrogation of each dataset. Readers could scroll through the data while evaluating image quality. Criteria and rankings are described below:

Overall image quality (5-point scale):

1 = non-diagnostic due to excessive noise artifacts

2 = diagnosis questionable due to excessive noise/artifacts; moderate decrease in diagnostic confidence

3 = diagnostic with moderate but acceptable noise/artifacts

4 = mild noise, no change in diagnostic confidence

5 = routine diagnostic image quality

Image sharpness (5-point scale):

1 = very sharp

2 = mildly unsharp edges, no diagnostic difference

3 = moderately unsharp, questionable diagnostic difference

4 = noticeable blur with poorly defined edges

5 = non-diagnostic

Image noise (4-point scale):

1 = less than usual

2 = optimal ‘routine’ noise

3 = increased noise, does not affect interpretation

4 = increased noise affecting interpretation

Noise texture (4-point scale):

0 = no noticeable change

1 = no noticeable change after window settings changed

2 = perceptible change

3 = blotchiness or change affecting confidence

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Fletcher, J.G., Hara, A.K., Fidler, J.L. et al. Observer performance for adaptive, image-based denoising and filtered back projection compared to scanner-based iterative reconstruction for lower dose CT enterography. Abdom Imaging 40, 1050–1059 (2015). https://doi.org/10.1007/s00261-015-0384-1

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  • DOI: https://doi.org/10.1007/s00261-015-0384-1

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