Pediatric 99mTc-DMSA SPECT Performed by Using Iterative Reconstruction with Isotropic Resolution Recovery: Improved Image Quality and Reduced Radiopharmaceutical Activity

Purpose: To compare two methods of reconstructing technetium 99m (99mTc) dimercaptosuccinic acid (DMSA) renal single photon emission computed tomographic (SPECT) data—ordered subset expectation maximization with three-dimensional resolution recovery (OSEM-3D) and filtered back projection (FBP)—in children in terms of improving image quality and reducing the radiopharmaceutical activity and radiation dose.

Materials and Methods: The institutional review board approved this retrospective study and waived the requirement for informed patient consent. Fifty sequential pediatric patient 99mTc-DMSA SPECT studies of 98 kidneys were retrospectively analyzed by using a dual-detector gamma camera. FBP reconstruction with data from both detectors was compared with OSEM-3D reconstruction with half the gamma photon counts (ie, data from only one detector). Two nuclear medicine physicians blinded to the patients' medical histories and reconstruction techniques evaluated the studies. Scores for image quality, renal size, and relative function were compared by using paired t tests. Total scores for renal cortical defects were compared by using the Wilcoxon signed rank test. The κ coefficient was calculated as an indicator of the concordance between the OSEM-3D and FBP reconstruction methods.

Results: Image quality was significantly enhanced with OSEM-3D (P < .001, paired t test). Cortical defects were identified better on OSEM-3D images than on FBP images. Of the 98 kidney SPECT studies analyzed, 19 showed identical cortical defects and 75 showed none at both OSEM-3D and FBP. In four kidneys, OSEM-3D depicted cortical defects that were not seen with FBP. No significant difference in relative renal function between the two methods was observed (P = .973).

Conclusion: Compared with FBP, OSEM-3D yielded superior image quality in the evaluation of 99mTc-DMSA renal SPECT data, with the potential for markedly reduced radiation doses and/or shorter scanning times for patients.

© RSNA, 2009


  • 1 Patton JA, Slomka PJ, Germano G, Berman DS. Recent technologic advances in nuclear cardiology. J Nucl Cardiol 2007; 14(4): 501–513. Crossref, MedlineGoogle Scholar
  • 2 Mawlawi O, Erwin W, Pan T, et al. Can whole body bone SPECT replace planar imaging when acquired over a similar duration? J Nucl Med 2006; 47(suppl 1): 62P. Google Scholar
  • 3 Mawlawi O, Erwin W, Pan T, et al. What is the optimal minimum whole body bone SPECT scan duration that can replace planar bone scintigraphy? J Nucl Med 2006; 48(suppl 2): 120P. Google Scholar
  • 4 Petrocelli R, Barnhart S, Girton T, et al. Routine clinical use of SPECT OSEM-3D improves confidence and diagnostic performance. J Nucl Med 2006; 47(suppl 2): 373P. MedlineGoogle Scholar
  • 5 Piepsz A, Blaufox MD, Gordon I, et al. Consensus on renal cortical scintigraphy in children with urinary tract infection: Scientific Committee of Radionuclides in Nephrourology. Semin Nucl Med 1999; 29(2): 160–174. Crossref, MedlineGoogle Scholar
  • 6 Applegate KE, Connolly LP, Davis RT, Zurakowski D, Treves ST. A prospective comparison of high-resolution planar, pinhole, and triple-detector SPECT for the detection of renal cortical defects. Clin Nucl Med 1997; 22(10): 673–678. Crossref, MedlineGoogle Scholar
  • 7 Joseph DB, Young DW, Jordon SP. Renal cortical scintigraphy and single proton emission computerized tomography (SPECT) in the assessment of renal defects in children. J Urol 1990; 144(suppl 2, pt 2): 595–597. Crossref, MedlineGoogle Scholar
  • 8 Tarkington MA, Fildes RD, Levin K, Ziessman H, Harkness B, Gibbons MD. High resolution single photon emission computerized tomography (SPECT) 99mtechnetium-dimercapto-succinic acid renal imaging: a state of the art technique. J Urol 1990; 144(suppl 2, pt 2): 598–600. Crossref, MedlineGoogle Scholar
  • 9 Pretorius PH, King MA, Pan TS, de Vries DJ, Glick SJ, Byrne CL. Reducing the influence of the partial volume effect on SPECT activity quantitation with 3D modeling of spatial resolution in iterative reconstruction. Phys Med Biol 1998; 43(2): 407–420. Crossref, MedlineGoogle Scholar
  • 10 Wells RG, King MA, Simkin PH, et al. Comparing filtered back projection and ordered-subsets expectation maximization for small-lesion detection and localization in 67Ga SPECT. J Nucl Med 2000; 41(8): 1391–1399. MedlineGoogle Scholar
  • 11 Treves ST, Davis RT, Fahey FH. Administered radiopharmaceutical doses in children: a survey of 13 pediatric hospitals in North America. J Nucl Med 2008; 49(6): 1024–1027. Crossref, MedlineGoogle Scholar
  • 12 Römer W, Reichel N, Vija HA, et al. Isotropic reconstruction of SPECT data using OSEM3D: correlation with CT. Acad Radiol 2006; 13(4): 496–502. Crossref, MedlineGoogle Scholar
  • 13 Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977; 33(1): 159–174. Crossref, MedlineGoogle Scholar
  • 14 Conover WJ. Practical nonparametric statistics. 3rd ed. New York, NY: Wiley, 1999; 352:–363. Google Scholar
  • 15 Miller TR, Wallis JW. Fast maximum-likelihood reconstruction. J Nucl Med 1992; 33(9): 1710–1711. MedlineGoogle Scholar
  • 16 Vija AH, Zeintl J, Chapman JT, et al. Development of rapid SPECT acquisition protocol for myocardial perfusion imaging. In: 2006 IEEE Nuclear Science Symposium, Medical Imaging Conference and 15th International Workshop on Room-Temperature Semiconductor X- and Gamma-Ray Detectors, Special Focus Workshops, NSS/MIC/RTSD. Portland, Ore: Institute of Electrical and Electronics Engineers, 2006; 1811–1816. Google Scholar
  • 17 Brenner DJ, Hall EJ. Computed tomography: an increasing source of radiation exposure. N Engl J Med 2007; 357(22): 2277–2284. Crossref, MedlineGoogle Scholar
  • 18 International Council on Radiation Protection. ICRP report 80: radiation dose to patients from radiopharmaceuticals. London, England: Pergamon Press, 1999. Google Scholar

Article History

Published in print: 2009