Prototype positron emission tomography insert with electro-optical signal transmission for simultaneous operation...

Area of Science:

• Medical Imaging
• Biophysics
• Neuroscience

Background:

• Simultaneous Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI) offers powerful capabilities for disease research and treatment monitoring.
• Existing systems face challenges with mutual interference between PET and MRI components.

Purpose of the Study:

• To develop a brain-sized PET detector ring insert for existing MRI systems.
• To achieve simultaneous PET and MRI acquisition of brain images without interference.
• To validate the feasibility of the PET insert for high-resolution imaging.

Main Methods:

• Utilized electro-optical coupling with analog modulated lasers and fiber optics to relay PET signals, electrically decoupling PET detectors from the MRI.
• Employed non-magnetic, MRI-compatible batteries for powering SiPM devices and low-power lasers.
• Applied compressed sensing techniques, specifically constant weight codes, to reduce electro-optical readout channels by 8-fold, leveraging the sparse nature of PET data.
• Constructed and tested two electro-optical detector modules within an RF-shielded gantry, both outside and inside a 3T MRI system.

Main Results:

• Demonstrated that electro-optical coupling effectively mitigates RF interference from the MRI system.
• Confirmed the feasibility of powering PET components using MRI-compatible batteries.
• Preliminary tests showed successful simultaneous PET/MRI data acquisition with reduced channel count.
• The system proved partially transmissive to the MRI's RF field, minimizing interference.

Conclusions:

• The developed brain-sized PET detector insert is a feasible technology for high-resolution simultaneous PET/MRI imaging.
• This innovation has significant potential for studying brain diseases, guiding novel treatments, and monitoring disease progression.
• The use of electro-optical coupling and compressed sensing represents a significant advancement in integrated PET/MRI system design.