Highlights
- •Dependency of 177Lu SPECT calibration factors on phantom size.
- •Influence of volume of interests on 177Lu SPECT calibration factors.
- •Effect of attenuation maps on 177Lu SPECT calibration factor.
- •ESSE performed better than TEW in simulations.
- •Scatter energy windows are suggested for improved TEW scatter correction.
Abstract
Purpose
The objective of this study was to evaluate the image degrading factors in quantitative
177Lu SPECT imaging when using both main gamma photopeak energies.
Methods
Phantom measurements with two different vials containing various calibrated activities
in air or water were performed to derive a mean calibration factor (CF) for large
and small volumes of interest (VOIs). In addition, Monte Carlo simulations were utilized
to investigate the effect of scatter energy window width, scatter correction method,
such as effective scatter source estimation (ESSE) and triple energy window (TEW),
and attenuation map on the quantification of 177Lu. Results: The measured mean CF using large and small VOIs in water was 4.50 ± 0.80
and 4.80 ± 0.72 cps MBq−1, respectively. Simulations showed a reference CF of 3.3 cps MBq−1 for the water-filled phantom considering all photons excluding scattered events.
By using the attenuation map generated for 190 keV photons, the calculated CFs for
113 keV and 208 keV are 10% lower than by using the weighted mean energy of 175 keV
for 177Lu. The calculated CF using the TEW correction was 17% higher than using the ESSE
method for a water-filled phantom. However, our findings showed that an appropriate
scatter window combination can reduce this difference between TEW and ESSE methods.
Conclusions
The present work implies that choosing a suitable width of scatter energy windows
can reduce uncertainties in radioactivity quantification. It is suggested to generate
the attenuation map at 113 keV and 208 keV, separately. Furthermore, using small VOIs
is suggested in CF calculation.
Keywords
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References
- In vivo quantification of 177Lu with planar whole-body and SPECT/CT gamma camera imaging.EJNMMI Phys. 2015; 2: 20
- 177Lu-AMBA: synthesis and characterization of a selective 177Lu-labeled GRP-R agonist for systemic radiotherapy of prostate cancer.J Nucl Med. 2006; 47: 1144-1152
- Radiation dosimetry for 177Lu-PSMA I&T in metastatic castration-resistant prostate cancer: absorbed dose in normal organs and tumor lesions.J Nucl Med. 2017; 58: 445-450
- 177Lu-labeled RGD-BBN heterodimeric peptide for targeting prostate carcinoma.Nucl Med Commun. 2013; 34: 909-914
- Quantitative SPECT/CT imaging of 177Lu with in vivo validation in patients undergoing peptide receptor radionuclide therapy.Mol Imaging Biol. 2015; 17: 909-914
- MIRD pamphlet no. 23: quantitative SPECT for patient-specific 3-dimensional dosimetry in internal radionuclide therapy.J Nucl Med. 2012; 53: 1310-1325
- Quantitative Nuclear Medicine Imaging: Concepts, Requirements and Methods.International Atomic Energy Agency, 2014
- MIRD pamphlet no. 26: joint EANM/MIRD guidelines for quantitative 177Lu SPECT applied for dosimetry of radiopharmaceutical therapy.J Nucl Med. 2016; 57: 151-162
- Multi-centre evaluation of accuracy and reproducibility of planar and SPECT image quantification: an IAEA phantom study.Z Med Phys. 2017; 27: 98-112
- Quantitative SPECT reconstruction using CT-derived corrections.Phys Med Biol. 2008; 53: 3099-3112
- Dosimetry for 177Lu-DKFZ-PSMA-617: a new radiopharmaceutical for the treatment of metastatic prostate cancer.Eur J Nucl Med Mol Imaging. 2016; 43: 42-51
- Uncertainty propagation for SPECT/CT-based renal dosimetry in 177Lu peptide receptor radionuclide therapy.Phys Med Biol. 2015; 60: 8329-8346
- Improving quantitative dosimetry in 177Lu-DOTATATE SPECT by energy window-based scatter corrections.Nucl Med Commun. 2014; 35: 522-533
- Individualized dosimetry in patients undergoing therapy with 177Lu-DOTA-D-Phe1-Tyr3-octreotate.EJNMMI Phys. 2010; 37: 212-225
- Quantitative accuracy of 177Lu SPECT reconstruction using different compensation methods: phantom and patient studies.EJNMMI Res. 2016; 6: 16
- Gamma camera calibration and validation for quantitative SPECT imaging with 177Lu.Appl Radiat Isot. 2016; 112: 156-164
- Accuracy of 177Lu activity quantification in SPECT imaging: a phantom study.EJNMMI Phys. 2017; 4: 2
- Accuracy and precision assessment for activity quantification in individualized dosimetry of 177Lu-DOTATATE therapy.EJNMMI Phys. 2017; 4: 7
- Quantitative Bildgebung für die Dosimetrie mit SPECT/CT.Nuklearmediziner. 2018; 41: 24-36
- Quantitative comparison between the commercial software STRATOS® by Philips and a homemade software for voxel-dosimetry in radiopeptide therapy.Physica Med. 2015; 31: 72-79
- Determination of gamma camera calibration factors for quantitation of therapeutic radioisotopes.EJNMMI Phys. 2018; 5: 8
- Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy.PLoS One. 2017; 12e0182888
- Quantitative 177Lu SPECT imaging using advanced correction algorithms in non-reference geometry.Physica Med. 2016; 32: 1745-1752
- A Monte Carlo program for the simulation of scintillation camera characteristics.Comput Methods Programs Biomed. 1989; 29: 257-272
- The influence of triple energy window scatter correction on activity quantification for 177Lu molecular radiotherapy.Phys Med Biol. 2016; 61: 5107-5121
- Comparison of residence time estimation methods for radioimmunotherapy dosimetry and treatment planning: Monte Carlo simulation studies.IEEE Trans Med Imaging. 2008; 27: 521-530
- A new method for modeling the spatially-variant, object-dependent scatter response function in SPECT.IEEE Nucl Sci Symp. 1996; 2: 1082-1086
- Collimator-Detector response compensation in SPECT.in: Zaidi H. Quantitative analysis in nuclear medicine imaging. Springer, US, Boston, MA2006: 141-166
- Characteristics of Bremsstrahlung emissions of 177Lu, 188Re, and 90Y for SPECT/CT quantification in radionuclide therapy.Physica Med. 2016; 32: 691-700
- Optimization of GATE simulations for whole-body planar scintigraphic acquisitions using the XCAT male phantom with 177Lu-DOTATATE biokinetics in a Siemens Symbia T2.Phys Med. 2017; 42: 292-297
- Accelerated image reconstruction using ordered subsets of projection data.IEEE Trans Med Imaging. 1994; 13: 601-609
- Triple energy window scatter correction technique in PET.IEEE Trans Med Imaging. 1994; 13: 641-648
- Monte Carlo calculation in nuclear medicine.CRC Press, Taylor & Francis Group, Boca Raton, FL2013
- Effect of image registration on 3D absorbed dose calculations in 177Lu-DOTATOC peptide receptor radionuclide therapy.Physica Med. 2018; 45: 177-185
- Performance measurement of positron emission tomography.National Electrical Manufacturers Association, Washington, D.C.2001
- Analysis of a SPECT OSEM reconstruction method with 3D beam modeling and optional attenuation correction: phantom studies.in: 2003 IEEE Nuclear Science Symposium Conference Record (IEEE Cat No03CH37515). 2003: 2662-2666
- Molecular anatomic imaging: PET-CT and SPECT-CT integrated modality imaging.2nd ed. Lippincott Williams & Wilkins, Philadelphia, USA2007
- Calculation and validation of the use of effective attenuation coefficient for attenuation correction in In-111 SPECT.Med Phys. 2005; 32: 3628-3635
- Morphology supporting function: attenuation correction for SPECT/CT, PET/CT, and PET/MR imaging.Q J Nucl Med Mol Imaging. 2016; 60: 25-39
Article info
Publication history
Accepted:
November 15,
2018
Received in revised form:
November 7,
2018
Received:
July 7,
2018
Identification
Copyright
© 2018 Published by Elsevier Ltd on behalf of Associazione Italiana di Fisica Medica.
