Energy Window and Collimator Optimization in Lutetium-177 Single-photon Emission Computed Tomography Imaging using...

Area of Science:

• Nuclear Medicine
• Medical Imaging Physics

Background:

• Lutetium-177 (Lu-177) SPECT imaging accuracy is compromised by scattered and penetrated photons.
• Scattered photon fractions must be assessed to optimize Lu-177 imaging and develop correction methods.

Purpose of the Study:

• To compare image quality using three different collimators for Lu-177 SPECT imaging.
• To determine optimal parameters for accurate Lu-177 activity quantification.

Main Methods:

• Simulated Siemens Medical System Symbia SPECT using SIMIND Monte Carlo code.
• Evaluated high-energy (HE), medium-energy (ME), and low-energy high-resolution collimators.
• Analyzed primary and scattered point spread functions across 20%, 15%, and 10% main-energy windows for Lu-177 point sources.

Main Results:

• A 20% main-energy window combined with an ME collimator was identified as optimal for Lu-177 imaging.
• The HE collimator is suitable when high resolution is not a primary requirement.

Conclusions:

• The study identifies the optimal energy window and collimator for Lu-177 SPECT imaging.
• Findings will aid in improving the quantification accuracy of Lu-177 in SPECT.