Reduced-count myocardial perfusion SPECT with resolution recovery

Area of Science:

• Nuclear Medicine
• Medical Imaging

Background:

• Myocardial perfusion SPECT (single-photon emission computed tomography) is crucial for diagnosing cardiac conditions.
• Reducing administered radiopharmaceutical activity is desirable to minimize patient radiation dose.
• Resolution recovery (RR) algorithms aim to improve image quality in low-count SPECT data.

Purpose of the Study:

• To evaluate the diagnostic quality of myocardial perfusion SPECT images reconstructed with RR algorithms using reduced radiopharmaceutical activity.
• To determine if RR can enable a reduction in administered activity without compromising image interpretability.

Main Methods:

• Reduced-count (half-count) SPECT data were compared with full-count data from 53 routine myocardial perfusion scans.
• Reconstruction was performed using standard ordered subset expectation maximization (OSEM) without RR and with RR software (Evolution RR and Flash 3D RR).
• Image quality, myocardial functional values, and report outcomes were assessed and compared between full-count and reduced-count datasets.

Main Results:

• No degradation in image quality was observed for scans reconstructed with RR on the GE Infinia camera.
• Ten percent of scans on the Siemens c.cam showed slightly reduced quality with RR and reduced counts.
• While some functional values showed statistically significant differences, they were not clinically significant; reporting outcomes were largely consistent.

Conclusions:

• Resolution recovery algorithms can produce diagnostic quality myocardial perfusion SPECT images with reduced data counts.
• A 50% reduction in administered activity was deemed too significant, but a 33% reduction is considered acceptable.
• Implementing RR allows for consistently adequate diagnostic images with lower radiopharmaceutical doses.