TY - JOUR
T1 - Validation of a method for accurate and highly reproducible quantification of brain dopamine transporter SPECT studies
AU - Jensen, Peter S
AU - Ziebell, Morten
AU - Skouboe, Glenna
AU - Khalid, Usman
AU - de Nijs, Robin
AU - Thomsen, Gerda
AU - Knudsen, Gitte M
AU - Svarer, Claus
PY - 2011/12/1
Y1 - 2011/12/1
N2 - In nuclear medicine brain imaging, it is important to delineate regions of interest (ROIs) so that the outcome is both accurate and reproducible. The purpose of this study was to validate a new time-saving algorithm (DATquan) for accurate and reproducible quantification of the striatal dopamine transporter (DAT) with appropriate radioligands and SPECT and without the need for structural brain scanning. Methods: In a reconstructed DAT SPECT image, DATquan automatically calculated the ratio at steady state of specifically bound radioligand to nondisplaceable radioligand in tissue (BP ND) within striatal ROIs that were delineated by use of a semiautomatic template-based alignment approach. DATquan was tested with 123I-N-(3-iodoprop- 2E-enyl)-2-β-carbomethoxy-3β-(4-methylphenyl) SPECT images from 15 patients. In each image, ROIs were first manually delineated, and then corresponding BP ND values were derived by an experienced physician. Afterward, 2 independent novice operators used DATquan to analyze the same 15 images. The resulting DATquan-derived BP ND data were compared with the data retrieved by manual delineation to assess the accuracy and reproducibility of DATquan. Also, the operational aspects of DATquan were assessed on the basis of measurements of the mean running time of the algorithm as well as on the basis of quantification of the overlap of the DATquandelineated ROIs obtained by the 2 operators. Results: The mean algorithm running time was 3 min, and the operators' striatal ROIs had a mean overlap of more than 82%. DATquanderived BP ND values obtained by the 2 operators showed high agreement (the mean difference was 0.00 [SD, 0.05] in the striatum, 0.02 [SD, 0.26] in the putamen, and 0.03 [SD, 0.43] in the caudate nucleus). The interoperator variability was 2.2% (SD, 1.3%) in the striatum, 11.7% (SD, 9.9%) in the putamen, and 12.9% (SD, 4.0%) in the caudate nucleus. DATquan-derived BP ND values showed high agreement with the values manually derived by the experienced delineator. Conclusion: DATquan is a freely available, accurate, and highly reproducible method for quantification of DAT binding in the brain by SPECT. Once implemented in clinics, DATquan will serve as a useful and time-saving tool.
AB - In nuclear medicine brain imaging, it is important to delineate regions of interest (ROIs) so that the outcome is both accurate and reproducible. The purpose of this study was to validate a new time-saving algorithm (DATquan) for accurate and reproducible quantification of the striatal dopamine transporter (DAT) with appropriate radioligands and SPECT and without the need for structural brain scanning. Methods: In a reconstructed DAT SPECT image, DATquan automatically calculated the ratio at steady state of specifically bound radioligand to nondisplaceable radioligand in tissue (BP ND) within striatal ROIs that were delineated by use of a semiautomatic template-based alignment approach. DATquan was tested with 123I-N-(3-iodoprop- 2E-enyl)-2-β-carbomethoxy-3β-(4-methylphenyl) SPECT images from 15 patients. In each image, ROIs were first manually delineated, and then corresponding BP ND values were derived by an experienced physician. Afterward, 2 independent novice operators used DATquan to analyze the same 15 images. The resulting DATquan-derived BP ND data were compared with the data retrieved by manual delineation to assess the accuracy and reproducibility of DATquan. Also, the operational aspects of DATquan were assessed on the basis of measurements of the mean running time of the algorithm as well as on the basis of quantification of the overlap of the DATquandelineated ROIs obtained by the 2 operators. Results: The mean algorithm running time was 3 min, and the operators' striatal ROIs had a mean overlap of more than 82%. DATquanderived BP ND values obtained by the 2 operators showed high agreement (the mean difference was 0.00 [SD, 0.05] in the striatum, 0.02 [SD, 0.26] in the putamen, and 0.03 [SD, 0.43] in the caudate nucleus). The interoperator variability was 2.2% (SD, 1.3%) in the striatum, 11.7% (SD, 9.9%) in the putamen, and 12.9% (SD, 4.0%) in the caudate nucleus. DATquan-derived BP ND values showed high agreement with the values manually derived by the experienced delineator. Conclusion: DATquan is a freely available, accurate, and highly reproducible method for quantification of DAT binding in the brain by SPECT. Once implemented in clinics, DATquan will serve as a useful and time-saving tool.
U2 - http://dx.doi.org/10.2967/jnmt.111.090324
DO - http://dx.doi.org/10.2967/jnmt.111.090324
M3 - Journal article
SN - 0091-4916
VL - 39
SP - 271
EP - 278
JO - Journal of Nuclear Medicine Technology
JF - Journal of Nuclear Medicine Technology
IS - 4
ER -