Introduction:
The purpose of the present work was to evaluate the imaging characteristics of 89Zr-PET in
comparison with those obtained using fluorine-18 Fluorodeoxyglucose (18F-FDG) PET (a gold standard tracer in PET
imaging) using a small-animal NanoScan PET/CT scanner.
Methods:
The system’s spatial resolution, sensitivity, uniformity, and image quality were measured on a Nano Scan
small-animal PET/CT scanner according to the NEMA NU4-2008 protocols. For reconstruction images, we used 2D and
3D reconstruction algorithms. The reconstruction methods included filter back projection (FBP), the ordered subsets
expectation maximization (OSEM) algorithm, and the 3D Tera-Tomo algorithm, which are developed for the NanoScan
small-animal PET/CT scanner.
Results:
The results obtained showed a significant difference in the spatial resolution for 89Zr as compared to 22Na and
18F when using a 2D reconstruction algorithm. Where the spatial resolution values were much enhanced by using the 3D
Tera-Tomo reconstruction for each isotope, the Full width at half maximum (FWHM) values were less than 1 for all
isotopes at the center of the field of view (FOV). This difference in spatial resolution is dependent on the positron range,
energy and the reconstruction method.
Conclusion:
The long half-life of 89Zr makes it an ideal positron emitter for performing immuno-PET, which is matched
with the biological half-life of intact mAbs. 89Zr can also give several advantages over other long half-life positron
emitters in relation to the overall imaging performance because of its relatively short positron range and simpler decay
scheme. The values of 89Zr sensitivity that were obtained in the present study were less than those of previous studies.
Suppression of 18F-FDG signal in the bladder on small animal PET-CT