mGluR₅ and GABA_A receptor-specific parametric PET atlas construction-PET/MR data processing pipeline, validation, and...

Area of Science:

• Neuroscience
• Radiology
• Medical Imaging

Background:

• Glutamate (mGluR5) and GABA (GABA-A) neuroreceptors are implicated in psychiatric disorders.
• In vivo distribution data for these neuroreceptors is limited.
• Accurate neuroreceptor maps can aid clinical studies and advanced neuroimaging analyses.

Purpose of the Study:

• To develop a comprehensive processing pipeline for creating standard-space, in vivo distribution maps of neuroreceptor binding potential (BP_ND) and total distribution volume (V_T).
• To generate atlases for mGluR5 and GABA-A neuroreceptors using simultaneously acquired PET and MR data.
• To validate the accuracy and utility of the generated maps and pipeline.

Main Methods:

• A processing pipeline was designed for simultaneous bolus-infusion PET and MR data.
• The pipeline was applied to [11C]ABP688-PET/MR and [11C]Flumazenil-PET/MR data from healthy male subjects.
• Generated V_T and BP_ND atlases were validated by assessing registration accuracy and percent error in standard space.

Main Results:

• Activity concentration templates, V_T, and BP_ND atlases for mGluR5 and GABA-A were successfully generated.
• Validation showed low percent errors (δABP = 3.0 ± 1.0%, δFMZ = 3.8 ± 1.4%) compared to tracer variabilities.
• PET-to-PET registrations using the new maps demonstrated higher accuracy than standard templates.

Conclusions:

• The generated neuroreceptor atlases are valuable resources for neuroscience research.
• The proposed processing pipeline is a robust tool for creating standardized PET data distributions.
• This work facilitates more accurate in vivo neuroreceptor quantification and analysis in clinical and research settings.