RT Journal Article
SR Electronic
T1 Effect of amplitude-based respiratory gating on image quantification
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1383
OP 1383
VO 56
IS supplement 3
A1 Arpit Gandhi
A1 Morand Piert
A1 Kirk Frey
YR 2015
UL http://jnm.snmjournals.org/content/56/supplement_3/1383.abstract
AB 1383 Objectives Respiratory motion causes blurring of lesions, underestimation of radionuclide uptake and overestimation of lesion volumes. Amplitude-based respiratory gating divides the respiratory cycle into different amplitude ranges and reconstructs images based on the range which corresponds to the smallest amount of respiratory motion. It thus reduces motion induced image blurring and improves quantification. This study sought to investigate the effect of a specific type of amplitude-based gating termed HD·Chest (HD) on image quantification1.Methods Whole body FDG-PET/CT was performed in 100 patients with lung lesions using a Siemens mCT scanner. Respiratory gating was performed using HD with images reconstructed with 35% of acquired PET data. The maximum standardized uptake value (SUVmax) and peak SUV (SUVpeak) of lung lesions were defined on gated and non-gated images. Lesions were grouped according to their anatomical location and histology. Differences in SUVmax and SUVpeak between gated and non-gated images were calculated and assessed using rank sign testing (Wilcoxon).Results With HD, SUVmax increased 14.4% (± 21.1) for all lesions, 10% (± 10.0) for lesions located in the upper lobes, and 20% (± 28.6%) for lesions located in the lower and middle lobes. SUVpeak increased by 8.3% (± 14.4) for all lesions with an average of 4.3% (± 5.8) increase in upper lobe and 13.5% (± 13.5) increase in lower and middle lobe lesions (p<0.05). HD increased measured FDG-uptake to a greater degree in lesions located in the lower and middle lobes compared to upper lobes (p<0.05). With HD, SUVmax increased similarly across tissue types. Adenocarcinomas demonstrated significantly lower SUVmax (11.3 ± 6.9) than squamous (16.4 ± 9.0) and small cell (20.0 ± 11.9) cancers consistent with previous reports2,3.Conclusions HD is a viable approach to correct the effect of respiratory motion on FDG PET image quantification with potential impact on diagnosis, response monitoring and radiation therapy planning.