Master's Thesis

Automatic Detection and Segmentation of Lung Lesions on CT scans using Deep Convolutional Neural Networks

João Francisco Lourenço Borges de Sá Carvalho2019

Key information

Authors:

João Francisco Lourenço Borges de Sá Carvalho (João Francisco Lourenço Borges de Sá Carvalho)

Supervisors:

Mário Alexandre Teles de Figueiredo (Mário Alexandre Teles de Figueiredo); Nickolas Papanikolaou

Published in

11/15/2019

Abstract

Lung cancer is the most pervasive and one of the deadliest types of cancer, leading to more than 2 million cases being diagnosed each year, and a mortality rate of 60%. CT screening trials have played a key role in improving early detection of lung cancer, which has shown to significantly improve patient survival. Apart from lesion detection, tumour segmentation is critical for developing radiomics signatures. In this work, we propose a novel hybrid approach for lung lesion detection and segmentation on CT scans, where the segmentation task is assisted by prior detection of regions containing lesions. For the detection task, we introduce a 2.5D residual deep CNN working in a sliding-window fashion, whereas segmentation is tackled by a modified residual U-Net with a weighted-dice plus cross-entropy loss. Experimental results on the LIDC-IDRI dataset and on the lung tumour task dataset within the Medical Segmentation Decathlon show competitive detection performance of the proposed approach (0.902 recall) and superior segmentation capabilities (0.709 dice score). Further validation of the models was also performed, with key components of both models tested through several ablation studies, in order to assess its contribution to the final models. These results confirm the high potential of simpler models, with lower hardware requirements, thus of more general applicability.

Publication details

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Fields of Science and Technology (FOS)

industrial-biotechnology - Industrial Biotechnology

Publication language (ISO code)

eng - English

Rights type:

Embargo lifted

Date available:

08/20/2020

Institution name

Instituto Superior Técnico