Performance evaluation of a high-resolution brain PET scanner using four-layer MPPC DOI detectors

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Instrumentation

Background:

• Positron Emission Tomography (PET) is crucial for brain imaging.
• High-resolution imaging is needed for detailed brain studies.
• Existing PET scanners may have limitations in resolution and field of view for comprehensive brain analysis.

Purpose of the Study:

• To develop and evaluate a novel high-resolution PET scanner specifically designed for brain imaging.
• To assess the performance characteristics, including spatial resolution and sensitivity, of the new PET scanner.
• To demonstrate the imaging capabilities of the scanner for both human and small animal brains.

Main Methods:

• Designed a four-layer depth of interaction detector with finely segmented LYSO scintillators and multi-pixel photon counters.
• Assembled 32 detector modules into a ring with a 430 mm diameter and 168 detector rings with a 1.2 mm pitch.
• Evaluated intrinsic and system spatial resolutions using a 0.25 mm diameter 22Na point source and list-mode dynamic RAMLA (LM-DRAMA), respectively.
• Measured system sensitivity using an 18F line source and assessed high count rate capability with a cylindrical phantom.

Main Results:

• Achieved system spatial resolutions less than 1.0 mm FWHM throughout the field of view.
• Measured a system sensitivity of 21.4 cps/kBq.
• Demonstrated high count rate capability with peak true counts of 249 kcps and noise equivalent count rate (NECR_2R) of 27.9 kcps at 11.9 kBq/ml.
• Successfully imaged human and small animal brains with acceptable quality for high-resolution determination.

Conclusions:

• The developed high-resolution PET scanner meets the requirements for detailed brain imaging.
• The scanner's performance, including sub-millimeter resolution and high sensitivity, is suitable for advanced clinical and pre-clinical research.
• This technology offers significant potential for advancing neuroscience and the diagnosis of neurological disorders.