The Effect of Low Dose CT Matrix Size Variation on Qualitative and Semi-Quantitative Analysis of Positron Emission Tomography (PET) Images

Document Type : Original Paper, Physics

Author

Nuclear Medicine Unit, Faculty of Medicine, Cairo University, Egypt.

Abstract

Objective: The purpose of the study was to
evaluate the qualitative and semiquantitative effects of using different lowdose computed tomography (CT) matrix
sizes for attenuation correction of PET
images. Methods: Co-registered 2-[F18]-
fluoro-2-deoxy-D-glucose (FDG)-PET and
CT images were acquired using a combined
PET/CT scanner according to a
standardized protocol. PET/CT
reconstruction was repeated using default
reconstruction protocols with different
matrix sizes for low dose CT (512,768 and
1024) in 25 patients. The resulting images
were analyzed qualitatively “image
quality” and semi-quantitatively using
“mean SUV & Signal to Noise Ratio
(SNR)”. Results: No significant difference
in the resulting attenuated corrected images
reconstructed with the different matrix
sizes either qualitatively or semiquantitatively.
Conclusion: The matrix size of the low
dose CT used in the attenuation correction
of PET images does not affect the image
quality or semi-quantitative parameters.


Keywords