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Optimisation of the OS-EM algorithm and comparison with FBP for image reconstruction on a dual-head camera: a phantom and a clinical 18F-FDG study

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Abstract

Iterative reconstruction algorithms, such as the ordered subsets expectation maximisation (OS-EM), are a promising alternative to filtered backprojection (FBP). The aims of this study were first to optimise the OS-EM algorithm in terms of iteration number and to study the usefulness of post-filtering, and second to compare OS-EM and FBP for image reconstruction on a fluorine-18 fluorodeoxyglucose (18F-FDG) dual-head camera (DHC). These two goals were addressed using phantom acquisitions. The performances of these algorithms were also studied in patient acquisitions performed on a DHC and a PET on the same day. Phantom experiments were performed on a DHC using a Jaszczak phantom containing six spheres filled with 18F-FDG, two background levels (0.95, 6.80 kBq/ml) and three object contrasts (5.9, 3.7, 2.7). The reconstruction algorithms were FBP with a Gaussian filter (FWHM 0.5–2 pixel width) and OS-EM using 8–128 equivalent iterations (equivalent to the ML-EM algorithm) with and without Gaussian post-filtering [OS-EM (iterations, pixel width)]. Contrast recovery coefficient (CRC) and noise characteristics were assessed. Twenty-two patients (21 male, one female; age 55±15 years) with lung cancer underwent, on the same day, PET (1 h post injection of 37 MBq/kg 18F-FDG) and DHC acquisitions (3 h post injection). DHC data were reconstructed using six methods: FBP (1), OS-EM (16), (40), (40,1), (64) and (64,1). These sets were evaluated by two observers and compared to PET reconstructed with OS-EM (16). The number of detected lesions and the visual quality were assessed. A marked improvement in CRC was observed with OS-EM as compared with FBP when more than 24 iterations were used. The CRC increased markedly from 8 to 40 iterations and then reached a plateau. The noise was stable until 40 iterations and then increased. The best compromise was obtained for OS-EM (32) and OS-EM (40,1). For the patient study, OS-EM provided images of better visual quality, but with no significant difference in detection sensitivity. OS-EM was superior to FBP in terms of contrast recovery and noise level. The optimal compromise between contrast recovery and noise was obtained for OS-EM (32) and (40,1) on the phantom study. The clinical study showed that OS-EM yielded images of better visual quality but with no improvement in terms of detection of lung cancer.

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References

  1. Ak I, Stokkel MP, Pauwels EK. Positron emission tomography with 2-[18F]fluoro-2-deoxy-d-glucose in oncology. Part II. The clinical value in detecting and staging primary tumours. J Cancer Res Clin Oncol 2000; 126:560–574.

    CAS  PubMed  Google Scholar 

  2. Ak I, Blokland JA, Pauwels EK, Stokkel MP. The clinical value of18F-FDG detection with a dual-head coincidence camera: a review. Eur J Nucl Med 2001; 28:763–778.

    Article  CAS  PubMed  Google Scholar 

  3. Bomanji JB, Costa DC, Ell PJ. Clinical role of positron emission tomography in oncology. Lancet Oncol 2001; 2:157–164.

    CAS  PubMed  Google Scholar 

  4. Meikle SR, Hutton BF, Bailey DL, Hooper PK, Fulham MJ. Accelerated EM reconstruction in total-body PET: potential for improving tumour detectability. Phys Med Biol 1994; 39:1689–1704.

    Article  Google Scholar 

  5. Liow JS, Strother SC. Practical tradeoffs between noise, quantitation, and number of iterations for maximum likelihood-based reconstructions. IEEE Trans Med Imaging 1991; 10:563–570.

    Article  Google Scholar 

  6. Liow JS, Strother SC. The convergence of object dependent resolution in maximum likelihood based tomographic image reconstruction. Phys Med Biol 1993; 38:55–70.

    Article  CAS  PubMed  Google Scholar 

  7. Hudson HM, Larkin RS. Accelerated image reconstruction using ordered subsets of projection data. IEEE Trans Med Imaging 1994; 13:601–609.

    Article  Google Scholar 

  8. Beekman FJ, Slijpen ET, Niessen WJ. Selection of task-dependent diffusion filters for the post-processing of SPECT images. Phys Med Biol 1998; 43:1713–1730.

    Google Scholar 

  9. Tiling R, Tatsch K, Sommer H, Meyer G. Technetium-99m-sestamibi scintimammography for the detection of breast carcinoma: comparison between planar and SPECT imaging. J Nucl Med 1998; 39:849–856.

    CAS  PubMed  Google Scholar 

  10. Blocklet D, Seret A, Popa N, Schoutens A. Maximum-likelihood reconstruction with ordered subsets in bone SPECT. J Nucl Med 1999; 40:1978–1984.

    CAS  PubMed  Google Scholar 

  11. Moka D, Eschner W, Voth E, Dietlein M, Larena-Avellaneda A, Schicha H. Iterative reconstruction: an improvement of technetium-99m MIBI SPET for the detection of parathyroid adenomas? Eur J Nucl Med 2000; 27:485–489.

    CAS  PubMed  Google Scholar 

  12. Zasadny KR, Wahl RL. Standardized uptake values of normal tissues at PET with 2-[fluorine-18]-fluoro-2-deoxy-d-glucose: variations with body weight and a method for correction. Radiology 1993; 189:847–850.

    CAS  PubMed  Google Scholar 

  13. Brix G, Zaers J, Adam LE, et al. Performance evaluation of a whole-body PET scanner using the NEMA protocol. National Electrical Manufacturers' Association. J Nucl Med 1997; 38:1614–1623.

    CAS  PubMed  Google Scholar 

  14. Martin WH, Delbeke D, Patton JA, Sandler MP. Detection of malignancies with SPECT versus PET, with 2-[fluorine-18]fluoro-2-deoxy-d-glucose. Radiology 1996; 198:225–231.

    CAS  PubMed  Google Scholar 

  15. Wahl RL, Cody RL, Hutchins GD, Mudgett EE. Primary and metastatic breast carcinoma: initial clinical evaluation with PET with the radiolabeled glucose analogue 2-[F-18]-fluoro-2-deoxy-d-glucose. Radiology 1991; 179:765–770.

    CAS  PubMed  Google Scholar 

  16. Muehllehner G, Buchin M, Dudek J. Performance parameters of a positron imaging camera. IEEE Trans Nucl Sci 1976; NS-23:528–537.

  17. Snyder DL, Miller MI, Thomas LJ, Politte DG. Noise and edge artifacts in maximum-likelihood reconstruction for emission tomography. IEEE Trans Med Imaging 1987; 6:228–238.

    Google Scholar 

  18. Wallis JW, Miller TR. Rapidly converging iterative reconstruction algorithms in single-photon emission computed tomography. J Nucl Med 1993; 34:1793–1800.

    CAS  PubMed  Google Scholar 

  19. Kadrmas DJ, Christian PE. Comparative evaluation of lesion detectability for 6 PET imaging platforms using a highly reproducible whole-body phantom with (22)Na lesions and localization ROC analysis. J Nucl Med 2002; 43:1545–1554.

    Google Scholar 

  20. Farquhar TH, Llacer J, Sayre J, Tai YC, Hoffman EJ. ROC and LROC analyses of the effects of lesion contrast, size, and signal-to-noise ratio on detectability in PET images. J Nucl Med 2000; 41:745–754.

    CAS  PubMed  Google Scholar 

  21. Farquhar TH, Llacer J, Hoh CK, et al. ROC and localization ROC analyses of lesion detection in whole-body FDG PET: effects of acquisition mode, attenuation correction and reconstruction algorithm. J Nucl Med 1999; 40:2043–2052.

    CAS  PubMed  Google Scholar 

  22. Ramos CD, Erdi YE, Gonen M, et al. FDG-PET standardized uptake values in normal anatomical structures using iterative reconstruction segmented attenuation correction and filtered back-projection. Eur J Nucl Med 2001; 28:155–164.

    Article  CAS  PubMed  Google Scholar 

  23. Paul AK, Tatsumi M, Yutani K, Fujino K, Hashikawa K, Nishimura T. Effects of iterative reconstruction on image contrast and lesion detection in gamma camera coincidence imaging in lung and breast cancers. Nucl Med Commun 2002; 23:103–110.

    Article  CAS  PubMed  Google Scholar 

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Acknowledgements

The authors thank R. Medeiros for his valuable advice in editing the manuscript. The author's research was supported in part by grants from the Ligue Régionale Contre le Cancer, Comité de l'Eure, and by grants allocated to the University Hospital of Bichat from the Direction of Clinical Research (DRC) of Assistance Publique of Paris (Protocol CEDIT 97).

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Correspondence to Pierre Véra.

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Gutman, F., Gardin, I., Delahaye, N. et al. Optimisation of the OS-EM algorithm and comparison with FBP for image reconstruction on a dual-head camera: a phantom and a clinical 18F-FDG study. Eur J Nucl Med Mol Imaging 30, 1510–1519 (2003). https://doi.org/10.1007/s00259-003-1246-6

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  • DOI: https://doi.org/10.1007/s00259-003-1246-6

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