Design of a Multi-Pinhole Collimator for I-123 DaTscan Imaging on Dual-Headed SPECT Systems in Combination with a...

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Neurology

Background:

• Current I-123 labeled DaTscan SPECT imaging for Parkinson's Disease (PD) focuses on the brain's interior.
• Accurate diagnosis and monitoring of PD require imaging the occipital lobe for striatal binding ratio (SBR) calculation.
• Existing SPECT systems face limitations in simultaneously acquiring high-resolution images of the brain interior and sufficient data from the occipital lobe.

Purpose of the Study:

• To propose and design a novel dual-collimator SPECT system combining multi-pinhole (MPH) and fan-beam collimators.
• To optimize the MPH collimator design for high resolution and sensitivity in imaging the brain's interior for PD diagnosis.
• To enable accurate SBR calculation by facilitating complete brain sampling, including the occipital lobe.

Main Methods:

• Analysis of 46 clinical DaTscan studies to define the volume of interest (VOI) and inform MPH collimator design.
• Setting a system spatial resolution of 4.7 mm for the MPH collimator, comparable to clinical PET systems.
• Comparison of system sensitivities for three MPH aperture array designs, selecting the 3x3 array for optimal performance.

Main Results:

• The designed MPH collimator achieves a spatial resolution of 4.7 mm, superior to typical SPECT fan-beam collimators.
• The 3x3 aperture array design demonstrated the highest sensitivity among the tested configurations.
• The combined sensitivity of the selected MPH apertures is comparable to ultra-high resolution fan-beam collimators (LEUHRF).

Conclusions:

• The proposed dual-collimator SPECT system, featuring MPH and fan-beam collimators, offers a promising approach for enhanced PD imaging.
• The MPH collimator design shows potential for high-resolution imaging of the brain's interior, crucial for early PD diagnosis.
• Further research involving simulations and combined reconstruction algorithms is recommended to validate and develop this innovative SPECT system.