ProfessorDaniel Leff

A) CLINICAL NEUROERGONOMICS

Neuroergonomics is the application of neuroscience to ergonomics and unlike traditional ergonomics that relies largely on psychological explanations for issues of human factors such as safety, response times and stress, neuroergonomics capitalizes on biological explanations and methods to improve human performance. “Surgical Neuroergonomics” seeks to capitalize on analyses of surgeons’ brain function to advance the understanding of learning, perception and decision-making in surgery through the use of functional brain imaging. Applications of this research include neuro-monitoring of the surgeon to improve objective assessment, training of future surgeons, through neural biofeedback enhance patient safety. Our teams' research work in this arena can be sub-categorised, as follows: 

• Surgical Skills Learning: to assess changes in cortical brain response associated with complex tasks acquisition and skills learning in surgery.

• Operative Decision-Making: to evaluate brain responses associated with operative decision-making and moderation of operative risk. 

• Fatigue Assessment and Fatigue Amelioration: fatigue leads to poor decision-making, skills degradation, and clinical errors. I capitalise on non-invasive functional brain imaging to detect critical fatigue-related changes in operator brain function. 

• Stress and Cognitive Load Assessment: to gain a better understanding of changes in the brain associated with dynamic temporal stress and cognitive workload.

B) IMAGING, SENSING & ROBOTICS FOR PRECISION BREAST SURGERY

Breast cancer incidence is increasing and it is the commonest cancer in females worldwide. Breast conserving surgery (BCS) is the most commonly performed surgical treatment for women with early stage breast cancer. Unfortunately, on average, approximately 20% of patients undergoing BCS require a re-operation for close or positive resection margins. Positive margins following excision of breast cancer correlates with a two-fold increase in ipsilateral breast tumour regional recurrence (IBTR). The reasons for high reoperation rates and ergo high positive or close margin rates following attempted BCS are multifactorial and include regional variation in histopathological definitions of margin status, ability to adequately image and localize impalpable disease, and the 3D perceptual skills of the operating surgeon as well as the desire to maintain cosmesis which may cause certain operators to be excessively conservative.

Research projects in this arena, include: 

• Confocal Microscopy: investigating the ability of custom built probe-based confocal laser endomicroscopy (pCLE) and commercial confocal systems (e.g. HistologTM, Samantree, Switzerland), an emerging imaging tool to image the morphology of neoplastic and non-neoplastic breast tissues for rapid in-vivo diagnostics. Co-lead of first UK prospective evaluation of HistologTM in "HiCOSH" Trial. 

• Near Infrared (NIR) Fluorescence Imaging: in collaboration with engineering colleagues at the Hamlyn Centre (Elson Lab) we are working to built, test and validate NIR imaging systems and fluorescence contrast agents (e.g. indocyanine green, 5-aminolevulinic acid) for image guided cancer surgery, providing a guiding light on oncoplastic wide excision (“GLOW”) towards curtiailing high rates of positive margins and re-operative interventions. In addition, working with leaders in academic chemistry (Tate) to develop new fluorescent probes to cancer targets we have identified.

 
• Intelligent Knife (iKnife): investigating the role of rapid evaporative ionisation mass spectroscopy (REIMS) which analyses the surgical smoke plume and is capable of differentiating between normal and malignant breast tissues based on differences in mass spectra and lipid metabolism. Co-lead of the CRUK funded “REI-EXCISE Trial”, a first in woman study which aims to validate the iKnife for oncological margin control in-vivo.

• Bio-Sensing: evaluating the application of a novel wireless tissue saturation monitor to assess autologous tissue flap health following reconstructive breast surgery, and wearable wireless wrist worn monitors (e.g. Axivity, Newcastle, United Kingdom) to track physical recovery following axillary surgery [“BRACELET study”] and to evaluate dynamic feedback to accelerate physical recovery ["OnTrack" Trials]. 

• “MAMMOBOT”: CI leading a multidisciplinary team to develop a novel flexible growing robot with navigation and sensing capabilities for early detection and treatment of breast cancer. 


C) TRIALS TO IMPROVE QUALITY OF LIFE FOR PATIENTS WITH BREAST DISEASES

• Reverse sequencing in breast reconstruction. Preoperative radiotherapy prior to autologous deep inferior epigastric artery (“PRADA” trial NCT02771938) reconstruction trial. Our work was published in Lancet Oncology [https://doi.org/10.1016/S1470-2045(22)00145-0] demonstrated that autologous abdominal based reconstruction and microsurgical anastomosis after radiotherapy is safe and technically feasible. Our ongoing work seeks to confirm clinical and cost effectiveness of reverse sequencing to improve breast related quality of life in breast cancer patients. Chief Investigator of the NIHR-HTA funded “PRADA-II” trial. 

https://www.imperial.ac.uk/department-surgery-cancer/research/surgery/clinical-trials/pradaii/

• Immediate versus delayed symmetrisation mammoplasty surgery. Our work explored the cost-benefit of performing two-team immediate contralateral symmetrisation surgery in women receiving therapeutic mammoplasty. Our work showed that immediate symmetrisation surgery led to a significant reduction in patient level information costs [10.1093/bjsopen/zrac073]. CI of the follow-up, prospective, controlled, non-randomised trial seeking to evaluate whether immediate symmetrisation surgery leads to improved patient experience, equivalent long term symmetry and to better assess the benefits of the approach for the wider NHS (“SYMMETRI” trial).

• Vacuum drainage of mammary abscess. Led the national quality improvement initiative investigating Mastitis and Mammary Abscess Management (“MAMMA”) http://mammastudy.com/ which demonstrated high national average rates of operative intervention for breast abscess [10.1093/bjs/znad333]. Chief Investigator of an NIHR RfPB funded randomised clinical trial seeking to explore the benefits of vacuum drainage of breast abscess for women in whom the standard of care is incision drainage and /or who have failed standard needle aspiration (“MAMMA-VAD” Trial). 

https://www.imperial.ac.uk/department-surgery-cancer/research/surgery/clinical-trials/mamma-vad-trial-management-of-mammary-abscess-with-vacuum-assisted-drainage/

D) TECHNICAL SKILLS ASSESSMENT IN ONCOPLASTIC BREAST SURGERY

Simulation may facilitate deliberate practice of index procedures in a safe environment, better prepare trainees prior to the real operating room experience and help bridge the gap between skills required for core breast surgical procedures and advanced techniques in an era of oncoplastic surgery. However, despite the diffusion of simulation training in certain surgical specialties such laparoscopic and vascular surgery, simulation training and skills assessment in breast surgery has been quiescent. Prior to our work in this area, breast trainees had yet to benefit from high-fidelity surgical simulations in order to refine and practice their skills, and assessment of technical competence amongst breast trainees remains subjective. There are few publications describing simulation training in breast surgery and reported are focused on axillary sentinel node surgery as opposed to surgery on the breast gland itself, and these studies lack objective validation. Recent and current projects include, as follows:

• Wide Local Excision: working with a model designer, on a project funded by Health Education England and the Pink Ribbon Foundation to co-develop a simulator to improve training and technical skills assessment in breast surgery.

• Axillary Node Clearance: In the era of “axillary de-escalation” trainees are struggling to achieve clinical competencies in axillary clearance. I co-developed and validated a simulator, developed a clinical assessment score and end-product assessment tool for objective evaluation of technical skills in axillary lymph clearance. The work was published in Annals of Surgery and presented in the prize section of Association of Breast Surgery. The simulator has been further developed to enable axillary reverse mapping and the Lymphatic Microsurgical Preventive Healing Approach (LYMPHA) and has been adopted by the American College of Surgeons for their advanced axillary management course. 

• Level II Oncoplastic Breast Conservation: co-developing simulation of advanced (level II) oncoplastic surgery such as mammoplasty models that facilitating large volume cancer resections and large breast parenchymal re-arrangements. This simulator was adopted by the European School of Surgery for training breast surgical training, and the American Society of Breast Surgery (ASBRS) to support their fellows breast surgery course, as well as their beginers, intermediate and advanced oncoplastic skills courses.

• Chest Wall Perforator Flap for Partial Breast Reconstruction: worked with SIMPEDIA to construct a chest wall perforator flap simulation that facilitates doppler assessment of LICAP and AICAP vessels, faciliates planning and mark-up, and enables surgical execution of partial breast reconstruction. The simulator has been adopted into the American Society of Breast Surgery (ASBRS) advanced oncoplastic course.