Title: A miniature tethered drop-in laparoscopic molecular imaging probe for intraoperative decision support in minimally invasive prostate cancer surgery
Funder: Department of Health and Social Care

Abstract: Research question We will investigate how to provide essential navigational and visualisation tools for surgeons to use the tethered laparoscopic molecular probe in accurate image-guided prostate cancer surgery. The final system will be evaluated in a clinical usability study and we will aim to create an interface and guidance system that is intuitive and simple for the user. Background Although surgery remains one of the primary treatment options for prostate cancer, it is often unsuccessful due to difficulties in detecting cancerous tissue during a procedure, and there is an urgent medical need to improve the intra-operative detection of cancer and improve patient outcomes and reduce healthcare costs. Firstly, surgeons often fail to remove all the cancerous tissue surrounding the primary tumour, as evidenced by a positive surgical margin which is reported in 11-38% of patients. Secondly, due to the challenges of intra-operative detection of cancer, surgeons perform an extended pelvic lymph node dissection and extensively dissect healthy lymphatic tissue. Aims and objectives To integrate an image sensor onto the tethered molecular probe and a method of surface profilometry to interpret the site of target 99mTc-PSMA activity from the probe s perspective, even for large probe articulations within the tightly constrained prostate operating space; To analyse output data from the molecular probe to improve the spatial localisation of 99mTc-PSMA by augmenting the onboard camera view as the probe is manipulated; To combine pose information on the tethered probe recorded from the perspective of the operating laparoscope such that the target activity can be located on the standard surgical view; To carry out a full clinical usability study to confirm that the functional prototype performance meets clinical demands. Methods We will modify the EnLight laparoscopic molecular probe so that additional image-guidance can be provided to the surgeons. This will consist of integrating a camera into the probe so that the sensing area can be better visualised, as well as adapting the device to allow it to be externally tracked within the standard laparoscope view. The device will also be fitted with a simple structured lighting device to locate the sensing site on the tissue surface. Together, these adaptations will allow a registration of the tracer activity (prostate cancer or lymph nodes) onto the endoscopic image. Clinical usability will be evaluated and the findings will be used to prepare for obtaining regulatory approval for in human studies. Timelines for delivery This is a three year project divided into seven workpackages and twelve milestones covering the technical work and the clinical usability evaluation tasks. Anticipated impact and dissemination The molecular probe is subject two priority patent applications made by Lightpoint Medical, which we will build on to provide a case for commercialisation and dissemination. If successful we will immediately begin the CE marking process as well as initiating human trials. We are already in contact with early adopters and evaluated how the device fits within healthcare system finance models. The ultimate impact will be to enable safer, more effective and lower cost surgeries.

Lay abstract: A British company called Lightpoint Medical has developed a device called the EnLight to help detect prostate cancer and support decision making during keyhole surgery, the primary treatment method for this high occurrence disease. EnLight is particularly used for surgery carried out by robots, which is very common for treating the prostate. EnLight can be put into the abdomen and grasped and operated by one of the surgical instruments to point towards different parts of the tissue that is being operated on. The device picks up the radiation (or energy) produced by a radioactive tracer called 99Tc that binds to prostate specific membrane antigen (PSMA), a chemical on the surface of the tumour cells, allowing the area to be scanned for the presence of cancer. It is called a molecular imaging tethered drop-in laparoscopic probe . EnLight has great potential, but there are some difficulties in using the device for prostate surgery. Primarily, interpreting the information recorded by the device is hard because the surgeon cannot always accurately see where it is pointing, especially when using an endoscope. In this project we will combine Imperial s expertise in surgical technology development, guidance, imaging, and optics, to produce a prototype surgical guidance system &ndash; together with Lightpoint&ndash; that can expand the capabilities of the EnLight and make it into an intuitive and essential device for prostate cancer surgery. We will allow the location of the radioactive tracer to be viewed on a monitor in the operating theatre. This image will also be registered to the standard endoscope view so that the surgeon can see the tracer location. The EnLight can then be scanned within the body to build up a picture of the radiation and plan safe surgery avoiding nerves. This will be evaluated in models of the pelvis ( phantoms ) as well as using tissue samples. The work will be guided by user requirement analysis and specifications drawn up at the start of the project and evaluated through performance, integration and usability testing, which is a standard method to ensure that the device works well within the current clinical procedure and that feedback is obtained from oncology surgeons on the usability of the device. The workpackages will be delivered through close collaboration between Lightpoint and Imperial. If the project is successful then a CE mark will allow us to continue to trial the device with our collaborating surgeon network across the UK and Europe with the intention of launching a commercial product as soon as possible.

Research activity codes: 4.2 EVALUATION OF MARKERS AND TECHNOLOGIES;6.4 SURGERY
Health categories: CANCER AND NEOPLASMS