Radiation dose reduction in myocardial perfusion imaging single-photon emission computed tomography/computed...

Area of Science:

• Radiology
• Nuclear Medicine
• Medical Physics

Background:

• Myocardial perfusion imaging (MPI) using single-photon emission computed tomography/computed tomography (SPECT/CT) involves radiation exposure.
• Optimizing SPECT/CT protocols is crucial for minimizing dosimetric impact while maintaining diagnostic quality.

Purpose of the Study:

• To evaluate the effectiveness of a dose-tracking software (Radimetrics) in optimizing SPECT/CT protocols for MPI.
• To assess the dosimetric improvements achieved through protocol optimization.

Main Methods:

• Utilized Radimetrics software to track and analyze dosimetric indices, including administered activity, CT dose index, dose length product, and size-specific dose estimates.
• Evaluated effective and equivalent organ doses before and after protocol optimization in a large patient cohort.

Main Results:

• Achieved a 17.8% reduction in administered activity for 2-day protocols and 4.5% for 1-day protocols.
• Reduced size-specific dose estimates by 50% per CT acquisition.
• Significantly decreased effective dose for 2-day MPI from 21.9±2.5 to 15.6±1.4 mSv and for 1-day MPI from 17.8±1.7 to 13.6±1.5 mSv.
• Nearly halved equivalent doses to organs like the heart and breast.

Conclusions:

• Dose-tracking software provides an effective and straightforward method for optimizing SPECT/CT protocols in MPI.
• Targeted adjustments to acquisition protocols can lead to considerable reductions in radiation dose.
• Real-time monitoring and corrective actions are facilitated by dose-tracking software, enhancing patient safety.