1. Department of Cellular Pathology, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK
2. Nuffield Department of Surgical Sciences, University of Oxford, Oxford OX3 9DU, UK
3. Department of Cellular Pathology, Royal Berkshire Hospital, Royal Berkshire NHS Foundation Trust, Reading RG1 5AN, UK
4. Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK
5. School of Electrical Engineering and Robotics, Queensland University of Technology, Brisbane, QLD 4000, Australia
6. Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford OX3 7LD, UK
7. NIHR Oxford Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK