Optimising Repair of the Thoracic Wall Following Thoracic Surgery

First Supervisor: Professor Kawal Rhode
Second Supervisor: Dr Christos Bergeles

Lung cancer is the most common cause of cancer death in the UK. Patients diagnosed in the early stages can undergo en-bloc resection surgery. The chest wall is resected to guarantee a good resection margin and has to be reconstructed. Adequate repair prevents lung herniation which would otherwise cause paradoxical breathing, shortness of breath and possibly recurrent infections. Current practice is to perform the repair using bone cement. The aim of this project is to develop and clinically test a novel patient-specific rib prosthesis based on accurate 3D reconstruction of the chest wall from the patient’s medical images. The prosthesis will be made using the same material previously used, i.e. methacrylate, adding the advantage of having a perfect 3D model of the chest wall, providing lung protection, better stability, improved breathing mechanics and better cosmetics while maintaining the low procedure cost. There will be significant potential socioeconomic impact.

Introduction
Lung cancer is the most common cause of cancer death in the UK. There are approximately 45,000 new cases per year and almost as many deaths per year. This is expected to increase by a factor of 1.5 over the next 15 years. The annual cost to the UK economy is an estimated £2.4b. Innovations in healthcare must take place to combat this disease.

Patients diagnosed in the early stages can undergo en-bloc resection surgery. Surgery in combination with chemotherapy or radiotherapy is a treatment option for locally advanced lung cancer involving the chest wall. The chest wall in this situation is resected to guarantee a good resection margin and has to be reconstructed. Adequate repair prevents lung herniation which would otherwise cause paradoxical breathing, shortness of breath and possibly recurrent infections. Current practice is to perform the repair using bone cement. Recently 3D titanium prostheses have been introduced but these are expensive.

Aims & Objectives
The aim of this project is to produce and clinically validate a novel patient-specific rib prosthesis based on accurate 3D reconstruction of the chest wall from the patient’s medical images. The prosthesis will be made using the same material previously used, i.e. methacrylate, adding the advantage of having a perfect 3D model of the chest wall, providing lung protection, better stability, improved breathing mechanics and a better cosmetics while maintaining the low procedure cost.

Workplan
Months1-3: Literature review and development of software skills;

Months4-9: Construct a statistical shape model of the ribs and sternum from historical patient imaging data and evaluate the use of this model for automated segmentation of new cases;

Months10-12: Write first paper and transfer report; apply for ethical approval for the clinical study;

Months13-24: Develop novel 3D printing technology to print a negative rib model and investigate methods to sterilise this model for use in the operating theatre; validate using historic patient data in terms of fidelity of the produced rib models; develop techniques using photogrammetry to track the chest wall surface in real-time and validate on healthy volunteers;

Months25-30: Carry out patient study in approximately 10 patients including post-operative assessment of chest wall motion; write second paper;

Months31-36: Investigate the use of 3D printers to directly print the rib models as a biological scaffold; write conference paper;

Months37-42: Write thesis.

Supervisory Team
Professor Rhode is an expert on translation healthcare technology research. He will bring expertise in the areas of medical imaging, statistical organ modelling, 3D printing and surface tracking technologies.
Dr Bergeles is an expert in medical mechatronics and will bring expertise in design and implementation of novel 3D printing technologies.
Mr Billie is an expert in thoracic malignancies and their treatment. He will provide the required clinical expertise to carry out this highly translation project.

The project has access to the excellent research facilities that are part of GSST and the School of Biomedical Engineering and Imaging Sciences that include dedicated research scanners, engineering laboratories and specialised hardware.