Influence of the Pixel Sizes of Reference Computed Tomography on Single-photon Emission Computed Tomography Image...

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Radiology

Background:

• Advanced SPECT reconstruction systems like xSPECT utilize computed tomography (CT) coordinate systems for enhanced spatial referencing.
• Understanding the impact of CT resolution on SPECT reconstruction is crucial for optimizing image quality and diagnostic accuracy.

Purpose of the Study:

• To investigate the influence of high-resolution CT frame-of-reference on xSPECT reconstruction quality.
• To determine if variations in CT image resolution affect the final SPECT image fidelity.

Main Methods:

• Utilized 99mTc line-source and NEMA image quality phantoms scanned with a SPECT/CT system.
• Performed xSPECT reconstructions using reference CT images with varied display field-of-view (DFOV) and pixel sizes.

Main Results:

• Reconstructed xSPECT image pixel sizes remained consistent (~2.4 mm) regardless of CT resolution.
• Key image quality metrics, including FWHM, recovery coefficient, and background variability, were unaffected by CT DFOV size.

Conclusions:

• The resolution of the CT frame-of-reference does not significantly influence the image quality of xSPECT reconstructed SPECT images.
• This suggests a robustness in the xSPECT system, simplifying reconstruction protocols.