Developing a PET/CT Foundation Model for Cross-Modal Anatomical and Functional Imaging
Journal:
arXiv
Published Date:
Mar 4, 2025
Abstract
In oncology, Positron Emission Tomography-Computed Tomography (PET/CT) is
widely used in cancer diagnosis, staging, and treatment monitoring, as it
combines anatomical details from CT with functional metabolic activity and
molecular marker expression information from PET. However, existing artificial
intelligence-driven PET/CT analyses rely predominantly on task-specific models
trained from scratch or on limited datasets, limiting their generalizability
and robustness. To address this, we propose a foundation model approach
specifically designed for multimodal PET/CT imaging. We introduce the
Cross-Fraternal Twin Masked Autoencoder (FratMAE), a novel framework that
effectively integrates whole-body anatomical and functional or molecular
information. FratMAE employs separate Vision Transformer (ViT) encoders for PET
and CT scans, along with cross-attention decoders that enable synergistic
interactions between modalities during masked autoencoder training.
Additionally, it incorporates textual metadata to enhance PET representation
learning. By pre-training on PET/CT datasets, FratMAE captures intricate
cross-modal relationships and global uptake patterns, achieving superior
performance on downstream tasks and demonstrating its potential as a
generalizable foundation model.