Guidance of Minimally Invasive Surgery with Photoacoustic Imaging
Minimally invasive surgery (MIS) using laparoscopes and endoscopes is increasingly used to biopsy or resect abnormal tissue inside the body in ways that are less traumatic to patients than conventional open surgery. During MIS the surgeon has a restricted field of view and minimal tactile feedback so engineers, physicists and surgeons are working together on novel methods to integrate pre-operative imaging such as CT, PET and MR, with advanced methods of tissue sensing to provide the minimally invasive surgeon with greatly increased information on the nature of visualised tissues and their relationships to vital structures.
Accurately identifying the nature and extent of abnormal tissues such as tumours will increase the safety and adequacy of their removal. While intra-operative ultrasound imaging is currently available to look at the internal structure of organs it is poor at determining the nature of abnormal tissues (e.g. are they cancerous or pre-malignant), the extent of local spread and their effect on the surrounding tissues.
The objective of this translational project is to investigate the potential of photoacoustic imaging to improve the effectiveness and safety of minimally invasive surgery by providing real-time tissue characterisation. Photoacoustic imaging is a new modality that provides information about the molecular composition of tissues and vascularity, which is complementary to ultrasound imaging. With this modality, pulsed (nanosecond scale) excitation light is safely delivered to tissue; structures that absorb this light fractionally rise in temperature and generate ultrasound waves.
The main application for this work will be liver surgery in which we are seeking to transform surgical practice by dramatically increasing the number of liver tumour resections that can be done by laparoscopic (keyhole) rather than open surgery. Liver cancer, both primary and secondary, is increasing in incidence but currently only about 10% of surgical resections are undertaken laparoscopically. Our ultimate goal is to increase this three-fold.
We are seeking an enthusiastic and committed student with an excellent Engineering, Physics or Maths first degree who wants to work on cutting edge research in a highly multi-disciplinary environment. The student will be involved with hands-on experimental work to create tissue phantoms and to develop ex vivo and in vivo tissue models, and with medical image computing to reconstruct and analyse photoacoustic and ultrasound images and integrate photoacoustics into a surgical guidance system. The project will involve a close collaboration between Medical Physics, the Centre for Medical Image Computing at UCL and the Liver Surgery research group at Royal Free Campus, UCL.