Multicenter Study of Quantitative SPECT: Reproducibility of ^99mTc Quantitation Using a Conjugated-Gradient...

Area of Science:

• Nuclear Medicine
• Medical Imaging

Background:

• Quantitative SPECT imaging is crucial for accurate diagnosis and treatment monitoring.
• Reproducibility of SPECT image reconstruction methods is essential for reliable clinical application.

Purpose of the Study:

• To assess the interinstitutional reproducibility of a specific quantitative SPECT (single-photon emission computed tomography) image reconstruction method.
• To evaluate the impact of dose calibrator accuracy on quantitative SPECT imaging results.

Main Methods:

• A multicenter study involving 6 institutions using a common phantom and 99mTc-pertechnetate.
• Quantitative SPECT images were reconstructed using a commercially available ordered-subset conjugate-gradient minimization method.
• Interinstitutional variation was assessed using the coefficient of variation, and dose calibrator accuracy was investigated.

Main Results:

• Radioactivity concentrations showed minimal variation under standard and clinical conditions across institutions.
• Interinstitutional variation in radioactivity concentration was found to be 4.20%.
• Bias in SPECT image radioactivity concentrations correlated with dose calibrator accuracy.

Conclusions:

• The evaluated quantitative SPECT reconstruction method demonstrates high reproducibility, similar to PET imaging.
• The method is reliable for quantitative imaging of large, homogeneous objects.
• Dose calibrator accuracy is a critical factor influencing quantitative SPECT results.