First imaging result with an ultrahigh resolution stationary MR compatible SPECT system

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Biomedical Engineering

Background:

• Magnetic Resonance Imaging (MRI) and Single Photon Emission Computed Tomography (SPECT) are powerful imaging modalities.
• Integrating SPECT with MRI offers complementary functional and anatomical information.
• Existing SPECT systems face challenges with magnetic field interference and spatial resolution.

Purpose of the Study:

• To design and evaluate a novel, ultrahigh resolution, stationary SPECT system compatible with MRI (MRC-SPECT).
• To leverage energy-resolved photon-counting (ERPC) detectors for improved SPECT performance.
• To address magnetic field-induced distortions in SPECT imaging within an MRI scanner.

Main Methods:

• Assembly of twenty ERPC CdTe detector modules in a compact ring for high angular sampling and detection efficiency.
• Utilization of 3D-printed polyamide gantry for MR compatibility and a robust detector support structure.
• Development of a charge collection model to compensate for magnetic field-induced spatial distortions.

Main Results:

• The MRC-SPECT system utilizes ERPC CdTe detectors with 350μm intrinsic resolution and 3-4 keV energy resolution.
• A stationary ring configuration with platinum pinhole inserts and lead apertures was implemented.
• A charge collection model was developed to accurately predict and compensate for magnetic field effects on image data.

Conclusions:

• The designed MRC-SPECT system demonstrates potential for ultrahigh resolution imaging directly within an MRI scanner.
• The integration of ERPC detectors and a magnetic field compensation model advances MR-compatible SPECT technology.
• This system offers a promising platform for combined functional and anatomical imaging with enhanced diagnostic capabilities.