Localise to segment: crop to improve organ at risk segmentation accuracy
This work addresses the need for more accurate organ segmentation to reduce costs and complications in radiotherapy treatment, representing an incremental improvement in medical imaging methods.
The study tackled the problem of improving organ-at-risk segmentation accuracy in radiotherapy by comparing a two-stage localisation and segmentation approach to a single-stage baseline, finding that the two-stage method significantly increased accuracy for the spleen, pancreas, and heart, with greater benefits for smaller organs.
Increased organ at risk segmentation accuracy is required to reduce cost and complications for patients receiving radiotherapy treatment. Some deep learning methods for the segmentation of organs at risk use a two stage process where a localisation network first crops an image to the relevant region and then a locally specialised network segments the cropped organ of interest. We investigate the accuracy improvements brought about by such a localisation stage by comparing to a single-stage baseline network trained on full resolution images. We find that localisation approaches can improve both training time and stability and a two stage process involving both a localisation and organ segmentation network provides a significant increase in segmentation accuracy for the spleen, pancreas and heart from the Medical Segmentation Decathlon dataset. We also observe increased benefits of localisation for smaller organs. Source code that recreates the main results is available at \href{https://github.com/Abe404/localise_to_segment}{this https URL}.