Impact of Novel Incorporation of CT-based Segment Mapping into a Conjugated Gradient Algorithm on Bone SPECT Imaging: Fundamental Characteristics of a Context-specific Reconstruction Method

Document Type : Original Article

Authors

Department of Clinical Radiology, Tottori University Hospital, Tottori, Japan

Abstract

Objective(s): The latest single-photon emission computed tomography (SPECT)/computed tomography (CT) reconstruction system, referred to as xSPECT Bone™, is a context-specific reconstruction system utilizing tissue segmentation information from CT data, which is called a zone map. The aim of this study was to evaluate the
effects of zone-map enhancement incorporated into the ordered-subset conjugated gradient minimization (OSCGM) reconstruction method on SPECT images.
Methods: Image quality with zone-map enhanced OSCGM (OSCGMz) and nonenhanced OSCGM methods was compared using various reconstruction parameters. The compartment phantom had 3 radioactive sections with CT values of about 1000, 250, and 0 HU. SPECT data were acquired using a lowenergy high-resolution (LEHR) collimator, with a 256×256 matrix and 2.4-mm pixel size. The performances of the 2 reconstruction methods (OSCGM vs.OSCGMz) were evaluated on the basis of %error, coefficient of variation (%CV), and normalized mean squared error (NMSE), and adequate iterative update numbers were determined. The relative CV representing the ratio of smoothed images to non-smoothed images was calculated to evaluate the effects of the Gaussian filter on each section set with different CT values.
Results: On comparing the OSCGM and OSCGMz methods, it was found that the %error of the OSCGMz method tended to show convergence with fewer updates, especially in the high CT value section mimicking bone absorption. In the water
section, the %CV of the OSCGMz method was lower than that of the OSCGM method. The NMSE minimum values for the OSCGM and OSCGMz methods were obtained at 30 and 20 updates, respectively. The relative CV for the OSCGMz
method in the water section decreased remarkably according to the size of the full width at half maximum (FWHM) of the Gaussian filter.
Conclusion: The zone-map enhancement contributed to SPECT reconstruction for the reproduction of radioactive concentrations in bone tissues, using a low number of OSCGM updates. Our findings indicated that the incorporation of zone maps into SPECT reconstruction might improve image quality.

Keywords

Main Subjects


1. Ritt P, Sanders J, Kuwert T. SPECT/CT technology. Clin Transl Imaging. 2014;2(6):445-57.
2. Mariani G, Bruselli L, Kuwert, T, Kim EE, Flotats A, Israel O, et al. A review on the clinical use of SPECT/CT. Eur J Nucl Med Mol Imaging. 2010; 37(10):1959-85.
3. Palmedo H, Marx C, Ebert A, Kreft B, Ko Y, Türler A. Whole-body SPECT/CT for bone scintigraphy: diagnostic value and effect on patient management in oncological patients. Eur J Nucl Med Mol Imaging. 2014;41(1):59-67.
4. Utsunomiya D, Shiraishi S, Imuta M, Tomiguchi S, Kawanaka K, Morishita S, et al. Added value of SPECT/CT fusion in assessing suspected bone metastasis: comparison with scintigraphy alone and nonfused scintigraphy and CT. Radiology. 2006;238(1):264-71.
5. Hoogendam JP, Veldhuis WB, Hobbelink MG, Verheijen RH, van den Bosch MA, Zweemer RP. 99mTc SPECT/CT versus planar lymphoscintigraphy for preoperative sentinel lymph node detection in cervical cancer: a systematic review and metaanalysis. J Nucl Med. 2015;56(5):675-80.
6. Chowdhury FU, Scarsbrook AF. The role of hybrid SPECT-CT in oncology: current and emerging clinical applications. Clin Radiol. 2008;63(3):241-51.
7. Bailey D, Willowson K. An evidence-based review of quantitative SPECT imaging and potential clinical applications. J Nucl Med. 2013;54(1):83-9.
8. Dewaraja YK, Frey EC, Sgouros G, Brill AB, Roberson P, Zanzonico PB, et al. MIRD pamphlet no. 23: quantitative SPECT for patient-specific 3-dimensional dosimetry in internal radionuclide therapy. J Nucl Med. 2012;53(8):1310-25.
9. Zeintl J, Vija AH, Yahil A, Hornegger J, Kuwert T. Quantitative accuracy of clinical 99mTc SPECT/CTusing ordered-subset expectation maximization with 3-dimensional resolution recovery, attenuation, and scatter correction. J Nucl Med. 2010;51(6):921-8.
10. Seret A, Nguyen D, Bernard C. Quantitative capabilities of four state-of-the-art SPECT-CT cameras. EJNMMI Res. 2012;2(1):45.
11. Ritt P, Vija H, Hornegger J, Kuwert T. Absolute quantification in SPECT. Eur J Nucl Med Mol Imaging. 2011;38(Suppl 1):S69-77.
12. Ma J, Vija AH. Evaluation of quantitation accuracy for xSPECT. Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC); 31 Oct.-7 Nov. 2015. P. 1-4.
13. Vija AH. Introduction to xSPECT technology: evolving multi-modal SPECT to become contextbased and quantitative. White Paper. 2013;7:1-29.
14. Kuji I, Yamane T, Seto A, Yasumizu Y, Shirotake S, Oyama M. Skeletal standardized uptake values obtained by quantitative SPECT/CT as an osteoblastic biomarker for the discrimination of active bone metastasis in prostate cancer. Eur J Hybrid Imaging. 2017;1(1):2.
15. Armstrong IS, Hoffmann SA. Activity concentration measurements using a conjugate gradient (Siemens xSPECT) reconstruction algorithm in SPECT/CT. Nucl Med Commun. 2016;37(11):1212-7.
16. Okuda K, Nakajima K, Yamada M, Wakabayashi H, Ichikawa H, Arai H, et al. Optimization of iterative reconstruction parameters with attenuation correction, scatter correction and resolution recovery in myocardial perfusion SPECT/CT. Ann Nucl Med. 2014;28(1):60-8.
17. Matsutomo N, Nagaki A, Yamao F, Sasaki M. Optimization of iterative reconstruction parameters with 3-dimensional resolution recovery, scatter and attenuation correction in 123I-FP-CIT SPECT. Ann Nucl Med. 2015;29(7):636-42.
18. Cachovan M, Vija AH, Hornegger J, Kuwert T. Quantification of 99m Tc-DPD concentration in the lumbar spine with SPECT/CT. EJNMMI Res. 2013;3(1):45.
19. Knoll P, Kotalova D, Köchle G, Kuzelka I, Minear G, Mirzaei S, et al. Comparison of advanced iterative reconstruction methods for SPECT/CT. Z Med Phys. 2012;22(1):58-69.
20. Adams MC, Turkington TG, Wilson JM, Wong TZ. A systematic review of the factors affecting accuracy of SUV measurements. AJR Am J Roentgenol. 2010;195(2):310-20.
21. Beck M, Sanders JC, Ritt P, Reinfelder J, Kuwert T. Longitudinal analysis of bone metabolism using SPECT/CT and 99mTcdiphosphonopropanedicarboxylic acid: comparison of visual and quantitative analysis. EJNMMI Res. 2016;6(1):60.
22. Hippeläinen E, Tenhunen M, Mäenpää H, Sohlberg A. Quantitative accuracy of 177Lu SPECT reconstruction using different compensation methods: phantom and patient studies. EJNMMI Res. 2016;6(1):16.
23. Lee H, Kim JH, Kang YK, Moon JH, So Y, Lee WW. Quantitative single-photon emission computed tomography/computed tomography for technetium pertechnetate thyroid uptake measurement. Medicine. 2016;95(27):e4170.