Psychogyios, Dimitrios;
(2025)
Deep Learning Architectures for
Disparity Estimation and
Segmentation in Surgery.
Doctoral thesis (Ph.D), UCL (University College London).
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Abstract
The introduction of robotics in the operating room has addressed significant limitations of minimally invasive surgery. By incorporating stereo endoscopic cameras, 3D displays, and intuitive control interfaces, robotic surgery systems provide surgeons with tools to enable more precise operations, while allowing the integration of computer-assisted intervention pipelines. A detailed 3D representation of the surgical environment is essential for existing computer-assisted intervention systems and holds promise for the advancement of surgical automation. This thesis focuses on the development of learning-based methods for estimating 3D information from stereo-endoscopic videos and addresses challenges related to data generation and stereo-matching approaches. To enhance data-driven algorithms that depend on high-quality training data, this thesis introduces a new stereoscopic dataset tailored for surgical environments, facilitating the evaluation and adaptation of 3D reconstruction techniques. Building on this foundation, a multi-task learning framework was developed for the simultaneous estimation of stereo disparity and surgical tool segmentation. This framework leverages shared network architectures to mitigate data scarcity and optimize inference time. Validation studies demonstrated that cross-task learning can enhance performance, enabling the model to adapt its disparity estimation capabilities using only monocular segmentation data, thus illustrating domain transferability. In addition, the thesis explores the application of neural rendering techniques through the development of realistic endoscopic illumination models based on Neural Radiance Fields. The introduced method extends conventional neural radiance field architectures to accurately model the unique illumination conditions found in surgical settings, enhancing the realism and fidelity of synthetic data generation. The integration of this illumination modelling technique facilitates the generation of realistic looking training datasets with low-noise depth, and pose data, contributing to the improvement of learning-based 3D reconstruction and depth estimation in surgical applications. The results highlight that such realistic synthetic data can be used for training and evaluation of deep learning models in surgery, ultimately helping to reduce the domain gap for machine learning models in surgical environments.
| Type: | Thesis (Doctoral) |
|---|---|
| Qualification: | Ph.D |
| Title: | Deep Learning Architectures for Disparity Estimation and Segmentation in Surgery |
| Open access status: | An open access version is available from UCL Discovery |
| Language: | English |
| Additional information: | Copyright © The Author 2025. Original content in this thesis is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by-nc/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request. |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Computer Science |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10210001 |
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