Vision-Language Pre-training (VLP) has shown the merits of analysing medical
images, by leveraging the semantic congruence between medical images and their
corresponding reports. It efficiently learns visual representations, which in
turn facilitates enhanced analysis and interpretation of intricate imaging
data. However, such observation is predominantly justified on single-modality
data (mostly 2D images like X-rays), adapting VLP to learning unified
representations for medical images in real scenario remains an open challenge.
This arises from medical images often encompass a variety of modalities,
especially modalities with different various number of dimensions (e.g., 3D
images like Computed Tomography). To overcome the aforementioned challenges, we
propose an Unified Medical Image Pre-training framework, namely UniMedI, which
utilizes diagnostic reports as common semantic space to create unified
representations for diverse modalities of medical images (especially for 2D and
3D images). Under the text's guidance, we effectively uncover visual modality
information, identifying the affected areas in 2D X-rays and slices containing
lesion in sophisticated 3D CT scans, ultimately enhancing the consistency
across various medical imaging modalities. To demonstrate the effectiveness and
versatility of UniMedI, we evaluate its performance on both 2D and 3D images
across 10 different datasets, covering a wide range of medical image tasks such
as classification, segmentation, and retrieval. UniMedI has demonstrated
superior performance in downstream tasks, showcasing its effectiveness in
establishing a universal medical visual representation