Self-supervised learning in vision-language processing exploits semantic alignment between imaging and text modalities. Prior work in biomedical VLP has mostly relied on the alignment of single image and report pairs even though clinical notes commonly refer to prior images. This does not only introduce poor alignment between the modalities but also a missed opportunity to exploit rich self-supervision through existing temporal content in the data. In this work, we explicitly account for prior images and reports when available during both training and fine-tuning. Our approach, named BioViL-T, uses a CNN-Transformer hybrid multi-image encoder trained jointly with a text model. It is designed to be versatile to arising challenges such as pose variations and missing input images across time. The resulting model excels on downstream tasks both in single- and multi-image setups, achieving state-of-the-art performance on (I) progression classification, (II) phrase grounding, and (III) report generation, whilst offering consistent improvements on disease classification and sentence-similarity tasks. We release a novel multi-modal temporal benchmark dataset, MS-CXR-T, to quantify the quality of vision-language representations in terms of temporal semantics. Our experimental results show the advantages of incorporating prior images and reports to make most use of the data.

本文提出一种名为 BioViL-T 的方法，使用了了同时训练和微调过程中的先前图像和报告，通过 CNN-Transformer 混合多图像编码器与文本模型协同训练，获得了最先进的性能，在单图像和多图像设置下实现了进展分类，短语接地和报告生成，并在疾病分类和句子相似性任务上持续提供改进，并使用一个新的多模态时间基准数据集 MS-CXR-T 表征了视觉语言表示的优劣。

利用时间结构进行生物医学视觉语言处理的学习