Implementation of an iterative scatter correction, the influence of attenuation map quality and their effect on absolute quantitation in SPECT

We investigated the accuracy of qSPECT, a quantitative SPECT reconstruction algorithm we have developed which employs corrections for collimator blurring, photon attenuation and scatter, and provides images in units of absolute radiotracer concentrations (kBq cm(-3)). Using simulated and experimental phantom data with characteristics similar to clinical cardiac perfusion data, we studied the implementation of a scatter correction (SC) as part of an iterative reconstruction protocol. Additionally, with experimental phantom studies we examined the influence of CT-based attenuation maps, relative to those obtained from conventional SPECT transmission scans, on SCs and quantitation. Our results indicate that the qSPECT estimated scatter corrections did not change appreciably after the third iteration of the reconstruction. For the simulated data, qSPECT concentrations agreed with images reconstructed using ideal, scatter-free, simulated data to within 6%. For the experimental data, we observed small systematic differences in the scatter fractions for data using different combinations of SCs and attenuation maps. The SCs were found to be significantly influenced by errors in image coregistration. The reconstructed concentrations using CT-based corrections were more quantitatively accurate than those using attenuation maps from conventional SPECT transmission scans. However, segmenting the attenuation maps from SPECT transmission scans could provide sufficient accuracy for most applications.

[1]  High-resolution absolute SPECT quantitation for I-131 distributions used in the treatment of lymphoma: a phantom study , 2000 .

[2]  Irène Buvat,et al.  Quantitative accuracy of dopaminergic neurotransmission imaging with (123)I SPECT. , 2003, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[3]  B. Tsui,et al.  A new method for modeling the spatially-variant, object-dependent scatter response function in SPECT , 1996, 1996 IEEE Nuclear Science Symposium. Conference Record.

[4]  Matt A. King,et al.  A dual-photopeak window method for scatter correction. , 1992, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[5]  R. Jaszczak,et al.  Improved SPECT quantification using compensation for scattered photons. , 1984, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[6]  K. Ogawa,et al.  A practical method for position-dependent Compton-scatter correction in single photon emission CT. , 1991, IEEE transactions on medical imaging.

[7]  J. H. Hubbell,et al.  Atomic form factors, incoherent scattering functions, and photon scattering cross sections , 1975 .

[8]  Matt A. King,et al.  Evaluation of right and left ventricular volume and ejection fraction using a mathematical cardiac torso phantom. , 1997, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[9]  Freek J. Beekman,et al.  Efficient fully 3-D iterative SPECT reconstruction with Monte Carlo-based scatter compensation , 2002, IEEE Transactions on Medical Imaging.

[10]  R. G. Wells,et al.  Analytical calculation of scatter distributions in SPECT projections , 1995 .

[11]  D P Harrington,et al.  Quantitative reconstruction for myocardial perfusion SPECT: an efficient approach by depth-dependent deconvolution and matrix rotation. , 1994, Physics in medicine and biology.

[12]  A. Evans,et al.  Correction for partial volume effects in PET: principle and validation. , 1998, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[13]  G. Gullberg,et al.  A slice-by-slice blurring model and kernel evaluation using the Klein-Nishina formula for 3D scatter compensation in parallel and converging beam SPECT. , 2000, Physics in medicine and biology.

[14]  S. Blinder,et al.  Implementation of an analytically based scatter correction in SPECT reconstructions , 2003, IEEE Transactions on Nuclear Science.

[15]  Eric C Frey,et al.  A Monte Carlo and physical phantom evaluation of quantitative In-111 SPECT , 2005, Physics in medicine and biology.

[16]  K. W. Logan,et al.  Single photon scatter compensation by photopeak energy distribution analysis , 1992, IEEE Trans. Medical Imaging.

[17]  E C Frey,et al.  Fast implementations of reconstruction-based scatter compensation in fully 3D SPECT image reconstruction. , 1998, Physics in medicine and biology.

[18]  C Lartizien,et al.  GATE: a simulation toolkit for PET and SPECT. , 2004, Physics in medicine and biology.

[19]  Z Liang,et al.  Quantitative cardiac SPECT in three dimensions: validation by experimental phantom studies. , 1998, Physics in medicine and biology.

[20]  Ronald J. Jaszczak,et al.  Physical Factors Affecting Quantitative Measurements Using Camera-Based Single Photon Emission Computed Tomography (Spect) , 1981, IEEE Transactions on Nuclear Science.

[21]  The effect of SPECT reconstruction corrections on the absolute and relative quantitative accuracy of myocardial perfusion studies , 2004, IEEE Symposium Conference Record Nuclear Science 2004..

[22]  Stephan Blinder,et al.  Experimental verification of 3D detector response compensation using the OSEM reconstruction method , 2001, 2001 IEEE Nuclear Science Symposium Conference Record (Cat. No.01CH37310).

[23]  Zheng Chang,et al.  Problems created in attenuation-corrected SPECT images by artifacts in attenuation maps: a simulation study. , 2005, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.