Organ localisation using supervised and semi supervised approaches combining reinforcement learning with imitation learning

TL;DR

This paper presents a semi-supervised and supervised approach for organ localization in CT images, effectively reducing the need for extensive annotated data while maintaining high accuracy.

Contribution

It introduces a novel method combining supervised and semi-supervised learning for multi-organ localization, addressing data scarcity issues in medical imaging.

Findings

Semi-supervised learning achieves comparable accuracy with less labeled data.

The method successfully localizes spleen and kidneys with fewer annotations.

SSL performs well across different labeled-unlabeled data mixes.

Abstract

Computer aided diagnostics often requires analysis of a region of interest (ROI) within a radiology scan, and the ROI may be an organ or a suborgan. Although deep learning algorithms have the ability to outperform other methods, they rely on the availability of a large amount of annotated data. Motivated by the need to address this limitation, an approach to localisation and detection of multiple organs based on supervised and semi-supervised learning is presented here. It draws upon previous work by the authors on localising the thoracic and lumbar spine region in CT images. The method generates six bounding boxes of organs of interest, which are then fused to a single bounding box. The results of experiments on localisation of the Spleen, Left and Right Kidneys in CT Images using supervised and semi supervised learning (SSL) demonstrate the ability to address data limitations with a much smaller data set and fewer annotations, compared to other state-of-the-art methods. The SSL performance was evaluated using three different mixes of labelled and unlabelled data (i.e.30:70,35:65,40:60) for each of lumbar spine, spleen left and right kidneys respectively. The results indicate that SSL provides a workable alternative especially in medical imaging where it is difficult to obtain annotated data.