Incremental Cross-view Mutual Distillation for Self-supervised Medical CT Synthesis

TL;DR

This paper introduces a self-supervised method for increasing the resolution of medical CT slices by synthesizing intermediate slices through incremental cross-view mutual distillation, improving diagnostic detail without ground-truth data.

Contribution

It proposes a novel incremental cross-view mutual distillation strategy for self-supervised CT slice synthesis, enhancing inter-slice resolution without requiring ground-truth intermediate slices.

Findings

Outperforms state-of-the-art algorithms in CT slice synthesis

Effective in increasing inter-slice resolution in large-scale datasets

Demonstrates significant qualitative and quantitative improvements

Abstract

Due to the constraints of the imaging device and high cost in operation time, computer tomography (CT) scans are usually acquired with low intra-slice resolution. Improving the intra-slice resolution is beneficial to the disease diagnosis for both human experts and computer-aided systems. To this end, this paper builds a novel medical slice synthesis to increase the between-slice resolution. Considering that the ground-truth intermediate medical slices are always absent in clinical practice, we introduce the incremental cross-view mutual distillation strategy to accomplish this task in the self-supervised learning manner. Specifically, we model this problem from three different views: slice-wise interpolation from axial view and pixel-wise interpolation from coronal and sagittal views. Under this circumstance, the models learned from different views can distill valuable knowledge to guide the learning processes of each other. We can repeat this process to make the models synthesize intermediate slice data with increasing inter-slice resolution. To demonstrate the effectiveness of the proposed approach, we conduct comprehensive experiments on a large-scale CT dataset. Quantitative and qualitative comparison results show that our method outperforms state-of-the-art algorithms by clear margins.