The local excision of rectal lesions : can improved visualisation and imaging optimise the chances of success?

• Main Author: Di Marco, Aimee Natasha
• Other Authors: Darzi, Ara W. ; Yang, Guang-Zhong
• Published: Imperial College London 2016
• Subjects: 610
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.733099

Rectal cancer and its precursor benign lesions are a significant health problem worldwide. The concept of their management has undergone a paradigm shift in recent years away from a focus solely on complete oncological clearance, towards a finely tuned balance between oncological outcome and functional results. This concept is of particular importance in the management of the elderly and of benign lesions, two areas likely to grow in demand with our aging populations and move towards adoption of screening programs. Historically, the local excision of rectal lesions was an operation of necessity in the absence of anaesthesia or antisepsis, but was reinvented as the Transanal Endoscopic MicroSurgical (TEMS) excision; a precise and highly skilled procedure designed to avoid the overtreatment and functional compromise of radical surgery. The technique and platform for TEMS requires significant financial outlay by an institution and even more commitment by a surgeon to undertake this ergonomically taxing operation. The need for a good method of local excision driven by population and attitudinal changes is therefore currently not met satisfactorily by the available platforms for local transanal excision. This thesis examines the context and development of the original TEMS platform and then analyses the subsequent developments, and the requirement for improvements. The key area of visualization: macroscopic and subsurface are selected for exploration: a phantom on which to test new concepts is validated and the introduction of a novel 3D macroscopic viewing system and a subsurface ultrasound imaging probe are described. Finally, the resulting 3D viewing system and ultrasound image augmentation are translated from bench to operating theatre in a patient case series: the process required to facilitate this and outcomes of this pilot study are presented. The hope is that this work will prepare the ground for further technical improvements to the platforms for transanal local excision and lead to a larger clinical trial.