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arXiv · 2109.01949

Improving Joint Learning of Chest X-Ray and Radiology Report by Word Region Alignment

Zhanghexuan Ji·Mohammad Abuzar Shaikh·Dana Moukheiber·Sargur Srihari·Yifan Peng·Mingchen Gao
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Abstract

Self-supervised learning provides an opportunity to explore unlabeled chest X-rays and their associated free-text reports accumulated in clinical routine without manual supervision. This paper proposes a Joint Image Text Representation Learning Network (JoImTeRNet) for pre-training on chest X-ray images and their radiology reports. The model was pre-trained on both the global image-sentence level and the local image region-word level for visual-textual matching. Both are bidirectionally constrained on Cross-Entropy based and ranking-based Triplet Matching Losses. The region-word matching is calculated using the attention mechanism without direct supervision about their mapping. The pre-trained multi-modal representation learning paves the way for downstream tasks concerning image and/or text encoding. We demonstrate the representation learning quality by cross-modality retrievals and multi-label classifications on two datasets: OpenI-IU and MIMIC-CXR

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Zhanghexuan Ji, Mohammad Abuzar Shaikh, Dana Moukheiber, Sargur Srihari, Yifan Peng, Mingchen Gao. 2021-09-04. Improving Joint Learning of Chest X-Ray and Radiology Report by Word Region Alignment. https://arxiv.org/abs/2109.01949

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