TY - JOUR
T1 - Towards standardization of absolute SPECT/CT quantification
T2 - a multi-center and multi-vendor phantom study
AU - Peters, Steffie M. B.
AU - van der Werf, Niels R.
AU - Segbers, Marcel
AU - van Velden, Floris H. P.
AU - Wierts, Roel
AU - Blokland, Koos J. A. K.
AU - Konijnenberg, Mark W.
AU - Lazarenko, Sergiy
AU - Visser, Eric P.
AU - Gotthardt, Martin
N1 - Funding Information:
The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007–2013) under grant agreement no. 602812 (BetaCure).
Publisher Copyright:
© 2019, The Author(s).
PY - 2019/12/26
Y1 - 2019/12/26
N2 - Absolute quantification of radiotracer distribution using SPECT/CT imaging is of great importance for dosimetry aimed at personalized radionuclide precision treatment. However, its accuracy depends on many factors. Using phantom measurements, this multi-vendor and multi-center study evaluates the quantitative accuracy and inter-system variability of various SPECT/CT systems as well as the effect of patient size, processing software and reconstruction algorithms on recovery coefficients (RC). Methods Five SPECT/CT systems were included: Discovery (TM) NM/CT 670 Pro (GE Healthcare), Precedence (TM) 6 (Philips Healthcare), Symbia Intevo (TM), and Symbia (TM) T16 (twice) (Siemens Healthineers). Three phantoms were used based on the NEMA IEC body phantom without lung insert simulating body mass indexes (BMI) of 25, 28, and 47 kg/m(2). Six spheres (0.5-26.5 mL) and background were filled with 0.1 and 0.01 MBq/mL Tc-99m-pertechnetate, respectively. Volumes of interest (VOI) of spheres were obtained by a region growing technique using a 50% threshold of the maximum voxel value corrected for background activity. RC, defined as imaged activity concentration divided by actual activity concentration, were determined for maximum (RCmax) and mean voxel value (RCmean) in the VOI for each sphere diameter. Inter-system variability was expressed as median absolute deviation (MAD) of RC. Acquisition settings were standardized. Images were reconstructed using vendor-specific 3D iterative reconstruction algorithms with institute-specific settings used in clinical practice and processed using a standardized, in-house developed processing tool based on the SimpleITK framework. Additionally, all data were reconstructed with a vendor-neutral reconstruction algorithm (Hybrid Recon (TM); Hermes Medical Solutions). Results RC decreased with decreasing sphere diameter for each system. Inter-system variability (MAD) was 16 and 17% for RCmean and RCmax, respectively. Standardized reconstruction decreased this variability to 4 and 5%. High BMI hampers quantification of small lesions (<10 ml). Conclusion Absolute SPECT quantification in a multi-center and multi-vendor setting is feasible, especially when reconstruction protocols are standardized, paving the way for a standard for absolute quantitative SPECT.
AB - Absolute quantification of radiotracer distribution using SPECT/CT imaging is of great importance for dosimetry aimed at personalized radionuclide precision treatment. However, its accuracy depends on many factors. Using phantom measurements, this multi-vendor and multi-center study evaluates the quantitative accuracy and inter-system variability of various SPECT/CT systems as well as the effect of patient size, processing software and reconstruction algorithms on recovery coefficients (RC). Methods Five SPECT/CT systems were included: Discovery (TM) NM/CT 670 Pro (GE Healthcare), Precedence (TM) 6 (Philips Healthcare), Symbia Intevo (TM), and Symbia (TM) T16 (twice) (Siemens Healthineers). Three phantoms were used based on the NEMA IEC body phantom without lung insert simulating body mass indexes (BMI) of 25, 28, and 47 kg/m(2). Six spheres (0.5-26.5 mL) and background were filled with 0.1 and 0.01 MBq/mL Tc-99m-pertechnetate, respectively. Volumes of interest (VOI) of spheres were obtained by a region growing technique using a 50% threshold of the maximum voxel value corrected for background activity. RC, defined as imaged activity concentration divided by actual activity concentration, were determined for maximum (RCmax) and mean voxel value (RCmean) in the VOI for each sphere diameter. Inter-system variability was expressed as median absolute deviation (MAD) of RC. Acquisition settings were standardized. Images were reconstructed using vendor-specific 3D iterative reconstruction algorithms with institute-specific settings used in clinical practice and processed using a standardized, in-house developed processing tool based on the SimpleITK framework. Additionally, all data were reconstructed with a vendor-neutral reconstruction algorithm (Hybrid Recon (TM); Hermes Medical Solutions). Results RC decreased with decreasing sphere diameter for each system. Inter-system variability (MAD) was 16 and 17% for RCmean and RCmax, respectively. Standardized reconstruction decreased this variability to 4 and 5%. High BMI hampers quantification of small lesions (<10 ml). Conclusion Absolute SPECT quantification in a multi-center and multi-vendor setting is feasible, especially when reconstruction protocols are standardized, paving the way for a standard for absolute quantitative SPECT.
KW - SPECT
KW - CT
KW - absolute quantification
KW - recovery coefficient
KW - performance evaluation
KW - QUANTITATIVE SPECT
KW - RADIONUCLIDE THERAPY
KW - MONTE-CARLO
KW - DOSIMETRY
KW - CANCER
KW - PET
KW - LU-177-DOTATATE
KW - ATTENUATION
KW - GUIDELINES
KW - QUALITY
U2 - 10.1186/s40658-019-0268-5
DO - 10.1186/s40658-019-0268-5
M3 - Article
C2 - 31879813
SN - 2197-7364
VL - 6
JO - EJNMMI Physics
JF - EJNMMI Physics
IS - 1
M1 - 29
ER -