Imperial College London

Mr Daniel Richard Leff

Faculty of MedicineDepartment of Surgery & Cancer

Reader in Breast Surgery
 
 
 
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Contact

 

+44 (0)20 3312 1947d.leff

 
 
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Location

 

Queen Elizabeth the Queen Mother Wing (QEQM)St Mary's Campus

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Summary

 

Publications

Publication Type
Year
to

145 results found

Patel R, Ashcroft J, Patel A, Ashrafian H, Woods A, Singh H, Darzi A, Leff Det al., 2019, The impact of transcranial direct current stimulation on upper-limb motor performance in healthy adults: A systematic review and meta-analysis, Frontiers in Neuroscience, Vol: 13, ISSN: 1662-453X

Background: Transcranial direct current stimulation (tDCS) has previously been reported to improve facets of upper limb motor performance such as accuracy and strength. However, the magnitude of motor performance improvement has not been reviewed by contemporaneous systematic review or meta-analysis of sham vs. active tDCS.Objective: To systematically review and meta-analyse the existing evidence regarding the benefits of tDCS on upper limb motor performance in healthy adults.Methods: A systematic search was conducted to obtain relevant articles from three databases (MEDLINE, EMBASE, and PsycINFO) yielding 3,200 abstracts. Following independent assessment by two reviewers, a total of 86 articles were included for review, of which 37 were deemed suitable for meta-analysis.Results: Meta-analyses were performed for four outcome measures, namely: reaction time (RT), execution time (ET), time to task failure (TTF), and force. Further qualitative review was performed for accuracy and error. Statistically significant improvements in RT (effect size −0.01; 95% CI −0.02 to 0.001, p = 0.03) and ET (effect size −0.03; 95% CI −0.05 to −0.01, p = 0.017) were demonstrated compared to sham. In exercise tasks, increased force (effect size 0.10; 95% CI 0.08 to 0.13, p < 0.001) and a trend towards improved TTF was also observed.Conclusions: This meta-analysis provides evidence attesting to the impact of tDCS on upper limb motor performance in healthy adults. Improved performance is demonstrable in reaction time, task completion time, elbow flexion tasks and accuracy. Considerable heterogeneity exists amongst the literature, further confirming the need for a standardised approach to reporting tDCS studies.

Journal article

Hadjiminas D, Leff D, Cunningham D, Thiruchelvam P, Hogben K, Al Mufti R, Vella J, Zacharioudakis K, Kontoulis T, Ramakrishnan R, Zhao Jet al., 2019, Can we see what is invisible? The role of MRI in the evaluation and management of patients with pathological nipple discharge, Breast Cancer Research and Treatment, Vol: 178, Pages: 115-120, ISSN: 0167-6806

Introduction: The aim of this study was to determine the ability of MRI to identify and assess the extent of disease in patients with pathological nipple discharge (PND) with an occult malignancy not evident on standard preoperative evaluation with mammography and ultrasound.Methods: Patients presenting to the breast unit of Imperial College Healthcare NHS Trust between December 2009 and December 2018 with PND and normal imaging were enrolled in the study. Pre-operative bilateral breast MRI was performed in all patients as part of our protocol and all patients were offered diagnostic microdochectomy. Results: A total of 82 patients fulfilled our selection criteria and were enrolled in our study. The presence of an intraductal papilloma (IDP) was identified as the cause of PND in 39 patients (48%), 15 patients had duct ectasia (DE-18%) and 4 patients had both an IDP and DE. Other benign causes were identified in 10 patients (12%). Despite normal mammography and ultrasound a malignancy was identified in 14 patients (17%). Eleven patients had DCIS (13.4%) , two had invasive lobular carcinoma and one patient had an invasive ductal carcinoma. The sensitivity of MRI in detecting an occult malignancy was 85.71% and the specificity was 98.53 %. The positive predictive value was 92.31% and the negative predictive value was 97.1%.Conclusions: Although a negative MRI does not exclude the presence of an occult malignancy the high sensitivity and specificity of this diagnostic modality can guide the surgeon and alter the management of patients with PND.

Journal article

Berthelot M, Ashcroft J, Boshier P, Henry FP, Hunter J, Lo B, Yang G-Z, Leff Det al., 2019, Use of near infrared spectroscopy and implantable Doppler for postoperative monitoring of free tissue transfer for breast reconstruction: a systematic review and meta-analysis, Plastic and Reconstructive Surgery Global Open, Vol: 7, Pages: 1-8, ISSN: 2169-7574

Background: Failure to accurately assess the perfusion of free tissue transfer (FTT) in the early postoperative periodmay contribute to failure, which is a source of major patient morbidity and healthcare costs.Goal: This systematic review and meta-analysis aims to evaluate and appraise current evidence for the use of nearinfrared spectroscopy (NIRS) and/or implantable Doppler (ID) devices compared with conventional clinicalassessment (CCA) for postoperative monitoring of FTT in reconstructive breast surgery.Methods: A systematic literature search was performed in accordance with the PRISMA guidelines. Studies in humansubjects published within the last decade relevant to the review question were identified. Meta-analysis using randomeffects models of FTT failure rate and STARD scoring were then performed on the retrieved publications.Results: 19 studies met the inclusions criteria. For NIRS and ID, the mean sensitivity for the detection of FTT failure is99.36% and 100% respectively, with average specificity of 99.36% and 97.63% respectively. From studies withsufficient reported data, meta-analysis results demonstrated that both NIRS (OR = 0.09 [0.02, 0.36], P < 0.001) and ID(OR = 0.39 [0.27, 0.95], P = 0.04) were associated with significant reduction of FTT failure rates compared to CCA.Conclusion: The use of ID and NIRS provide equivalent outcomes in detecting FTT failure and were superior to CCA.The ability to acquire continuous objective physiological data regarding tissue perfusion is a perceived advantage ofthese techniques. Reduced clinical staff workload and minimised hospital costs are also perceived as positiveconsequences of their use.

Journal article

Muthuswamy K, Fisher R, Petrou F, Mavroveli S, Leff DRet al., 2019, Axillary lymph node dissection training in a post‐Z0011 era: A survey of UK breast surgery trainees, The Breast Journal, Vol: 25, Pages: 1037-1041, ISSN: 1075-122X

Journal article

Modi HN, Singh H, Fiorentino F, Orihuela-Espina F, Athanasiou T, Yang G-Z, Darzi A, Leff DRet al., 2019, Association of residents' neural signatures with stress resilience during surgery, JAMA Surgery, Vol: 154, ISSN: 2168-6254

Importance: Intraoperative stressors may compound cognitive load, prompting performance decline and threatening patient safety. However, not all surgeons cope equally well with stress, and the disparity between performance stability and decline under high cognitive demand may be characterized by differences in activation within brain areas associated with attention and concentration such as the prefrontal cortex (PFC). Objective: To compare PFC activation between surgeons demonstrating stable performance under temporal stress with those exhibiting stress-related performance decline. Design, Setting, and Participants: Cohort study conducted from July 2015 to September 2016 at the Imperial College Healthcare National Health Service Trust, England. One hundred two surgical residents (postgraduate year 1 and greater) were invited to participate, of which 33 agreed to partake. Exposures: Participants performed a laparoscopic suturing task under 2 conditions: self-paced (SP; without time-per-knot restrictions), and time pressure (TP; 2-minute per knot time restriction). Main Outcomes and Measures: A composite deterioration score was computed based on between-condition differences in task performance metrics (task progression score [arbitrary units], error score [millimeters], leak volume [milliliters], and knot tensile strength [newtons]). Based on the composite score, quartiles were computed reflecting performance stability (quartile 1 [Q1]) and decline (quartile 4 [Q4]). Changes in PFC oxygenated hemoglobin concentration (HbO2) measured at 24 different locations using functional near-infrared spectroscopy were compared between Q1 and Q4. Secondary outcomes included subjective workload (Surgical Task Load Index) and heart rate. Results: Of the 33 participants, the median age was 33 years, the range was 29 to 56 years, and 27 were men (82%). The Q1 residents demonstrated task-induced increases in HbO2 across the bilateral ventrolateral PFC (VLPFC) and right dorsolateral P

Journal article

Berthelot M, Henry FP, Hunter J, Leff D, Wood S, Jallali N, Dex E, Ladislava L, Lo B, Yang GZet al., 2019, Pervasive wearable device for free tissue transfer monitoring based on advanced data analysis: clinical study report, Journal of Biomedical Optics, Vol: 24, Pages: 067001-1-067001-8, ISSN: 1083-3668

Free tissue transfer (FTT) surgery for breast reconstruction following mastectomy has become a routineoperation with high success rates. Although failure is low, it can have a devastating impact on patient recovery,prognosis and psychological well-being. Continuous and objective monitoring of tissue oxygen saturation (StO2) hasshown to reduce failure rates through rapid detection time of postoperative vascular complications. We have developeda pervasive wearable wireless device that employs near infrared spectroscopy (NIRS) to continuously monitor FTTviaStO2measurement. Previously tested on different models, this paper introduces the results of a clinical study. Thegoal of the study is to demonstrate the developed device can reliably detectStO2variations in a clinical setting: 14patients were recruited. Advanced data analysis were performed on theStO2variations, the relativeStO2gradientchange, and, the classification of theStO2within different clusters of blood occlusion level (from 0% to 100% at 25%step) based on previous studies made on a vascular phantom and animals. The outcomes of the clinical study concurwith previous experimental results and the expected biological responses. This suggests the device is able to correctlydetect perfusion changes and provide real-time assessment on the viability of the FTT in a clinical setting.

Journal article

Modi H, Singh H, Fiorentino F, Orihuela-Espina F, Athanasiou T, Yang G-Z, Darzi A, Leff Det al., Neural signatures of resident resilience, JAMA Surgery, ISSN: 2168-6254

Importance: Intraoperative stressors may compound cognitive load, prompting performance decline and threatening patient safety. However, not all surgeons cope equally well with stress, and the disparity between performance stability and decline under high cognitive demand may be characterized by differences in activation within brain areas associated with attention and concentration such as the prefrontal cortex (PFC).Objective: To compare PFC activation between surgeons demonstrating stable performance under temporal stress with those exhibiting stress-related performance decline. The a priori hypothesis being that under temporal demand sustained prefrontal “activation(s)” reflect performance stability, whereas performance decline is manifest as “deactivation(s)”.Design: Cohort study conducted from July 2015 to September 2016. Setting: Single center (Imperial College Healthcare NHS Trust, United Kingdom). Participants: 102 surgical residents (PGY1 and above) were invited to participate, of which 33 agreed to partake (median age [range]: 33 [29-56] years, 27 [82%] males).Exposure: Subjects performed a laparoscopic suturing task under two conditions: ‘self-paced’ (SP; without time per knot restrictions), and ‘time pressure’ (TP; two-minute per knot time restriction). Main Outcomes and Measures: A composite deterioration score was computed based on between-condition differences in task performance metrics [(task progression score (au), error score (mm), leak volume (ml) and knot tensile strength (N)]. Based on the composite score, quartiles were computed reflecting performance stability (Q1) and decline (Q4). Changes in PFC oxygenated haemoglobin concentration (HbO2) measured at 24 different locations using functional near-infrared spectroscopy were compared between Q1 and Q4. Secondary outcomes included subjective workload (Surgical Task Load Index) and heart rate. Results: Q1 residents demonstrated task-induced incr

Journal article

Grant Y, Al-Khudairi R, St John E, Barschkett M, Cunningham D, Al-Mufti R, Hogben K, Thiruchelvam P, Hadjiminas DJ, Darzi A, Carter AW, Leff DRet al., 2019, Patient-level costs in margin re-excision for breast-conserving surgery, British Journal of Surgery, Vol: 106, Pages: 384-394, ISSN: 1365-2168

BackgroundHigh rates of reoperation following breast‐conserving surgery (BCS) for positive margins are associated with costs to healthcare providers. The aim was to assess the quality of evidence on reported re‐excision costs and compare the direct patient‐level costs between patients undergoing successful BCS versus reoperations after BCS.MethodsThe study used data from women who had BCS with or without reoperation at a single institution between April 2015 and March 2016. A systematic review of health economic analysis in BCS was conducted and scored using the Quality of Health Economic Studies (QHES) instrument. Financial data were retrieved using the Patient‐Level Information and Costing Systems (PLICS) for patients. Exchange rates used were: US $1 = £0·75, £1 = €1·14 and US $1 = €0·85.ResultsThe median QHES score was 47 (i.q.r. 32·5–79). Only two of nine studies scored in the upper QHES quartile (score at least 75). Costs of initial lumpectomy and reoperation were in the range US $1234–11786 and $655–9136 respectively. Over a 12‐month interval, 153 patients had definitive BCS and 59 patients underwent reoperation. The median cost of reoperations after BCS (59 patients) was £4511 (range 1752–18 019), representing an additional £2136 per patient compared with BCS without reoperation (P < 0·001).ConclusionThe systematic review demonstrated variation in methodological approach to cost estimates and a paucity of high‐quality cost estimate studies for reoperations. Extrapolating local PLICS data to a national level suggests that getting BCS right first time could result in substantial savings.

Journal article

Chidambaram S, Erridge S, Leff D, Purkayastha Set al., 2019, A randomized controlled trial of skills transfer: from touch surgery to laparoscopic cholecystectomy, Journal of Surgical Research, Vol: 234, Pages: 217-223, ISSN: 0022-4804

BackgroundSurgical training has traditionally involved teaching trainees in the operating room. However, intraoperative training is time-intensive and exposes patients to greater risks. Touch Surgery (TS) is an application that uses animation to provide simulation training via cognitive task analysis as an adjunct to intraoperative training.MethodsForty students were recruited and randomly allocated to either a control or intervention group. Each group received the same preparation before intervention, including a 10-min introduction to laparoscopic equipment and a 15-min educational tutorial on laparoscopic cholecystectomies. The participants then received training via either TS (intervention) or written information (control). Their performance was compared using a validated scoring tool on a porcine laparoscopic cholecystectomy model. Significance was defined as P < 0.050.ResultsIn total, n = 22 and n = 18 participants were randomly assigned to intervention and control groups, respectively. There was no significant difference between age (P = 0.320), year of medical school (P = 0.322), handedness (P = 1.000), or gender (P = 0.360) of the groups. The overall mean performance score was higher for intervention (mean ± SD = 41.9 ± 22.5) than control (mean ± SD = 24.7 ± 19.6; P = 0.016). There was no significant difference between scores for each intraoperative segment between the intervention and control group (P > 0.050).ConclusionsThis study demonstrates that TS is effective for providing cognitive training in laparoscopic cholecystectomies to medical students. It is likely that this effect will be seen across modules and other platforms that use cognitive task analysis alongside high-fidelity animation. Further work is necessary to extend this to other surgical procedures for evaluating its longitudinal effectiveness.

Journal article

Leiloglou M, Chalau V, Kedrzycki M, Qi J, Martin-Gonzalez P, Hanna G, Darzi A, Leff D, Elson Det al., Fluorescence Intensity Image Guided Breast Conserving Surgery (BCS)., European Molecular Imaging Meeting

Conference paper

Leiloglou M, Chalau V, Kedrzycki M, Avila-Rencoret F, Li Q, Lin J, Hanna G, Darzi A, Leff D, Elson Det al., Snapshot Fluorescence Hyperspectral System for Breast Cancer Surgery Guidance, Hamlyn Symposium Advanced Biophotonics Workshop

Conference paper

Kedrzycki M, Leiloglou M, Chalau V, Leff D, Elson Det al., Highlighting Breast Cancer: First-in-Human Testing of the Imperial Camera System for Fluorescence Guided Breast Cancer Surgery, London Surgery Symposium

Conference paper

Hall A, Leff D, Wojdecka A, Kinross J, Thompson P, Darzi Aet al., 2019, Beyond the healthcare paradigm: Co-creating a new model for collaborative transdisciplinary healthcare design education

© 2019 Institution of Engineering Designers, The Design Society. All rights reserved. Although healthcare has long been a focus for design research dating from the 1960’s and Bruce Archer’s Industrial Design (Engineering) research unit, there remain very few academic programmes in the field of healthcare design and even fewer that go beyond classic user driven models. This paper reports on a unique collaboration between the Royal College of Art and Imperial College in London to develop an innovative partnership and programme structure between two diverse collaborating institutions. Moreover, the partnership has shown how new design and healthcare research methods have been used for innovative practice-based healthcare design projects. We reflect on the diverse skill sets and approaches that have evolved through collaborative teamwork between healthcare practitioners, designers and diverse disciplinary backgrounds. Our conclusions illustrate how a context driven programme provides evidence of a new ‘post-disciplinary’ mindset and explores implications for research and practice for the future of healthcare design.

Conference paper

Ashcroft J, Patel R, Singh H, Darzi A, Leff Det al., The Impact of Transcranial direct current stimulation (tDCS) on a surgical knot-tying task, Surgery and Cancer Research Afternoon Abstract

Conference paper

Leff DR, Patani N, Finn M, Eshleby S, Omar A, Kaur A, Contractor K, Thiruchelvam P, Curtis S, Main J, Cunningham D, Hogben K, AlMufti R, Hadjiminas DJet al., 2018, A ‘best practice’ care pathway improves management of mastitis and breast abscess, British Journal of Surgery, Vol: 105, Pages: 1615-1622, ISSN: 1365-2168

Background: As a result of surgical sub-specialisation, mastitis and breast abscess may be managed with unnecessary hospitalisation, prolonged admission, variable antibiotic prescribing, incision and drainage rather than aspiration, and loss to follow-up. Objective: To evaluate a ‘best-practice’ algorithm to improve management across a multi-site NHS Trust; focusing on uniformity of antibiotic prescribing, ultrasound assessment, admission rates, length of stay, intervention by aspiration or incision and drainage, and follow-up. Methods: Management was initially evaluated in a retrospective cohort (Phase-I: “PRE-pathway”, n=53) and subsequently compared to two prospective cohorts (Phase II and III = “POST-pathway”, n=141), one immediately following pathway introduction (Phase II n=61), and a further loop-closing audit (Phase-III, n=80) to assess sustainability of quality improvements. Results: The management pathway and referral proforma improved compliance with antibiotic guidelines (Pre=34.0% vs. Post=58.2%, p<0.01), which was maintained (Phase-II=54.1% vs. III=61.3%, p=0.68) and sustainably increased ultrasound assessment (Pre=37.7% vs. Post=77.3%, p<0.001; Phase-II=75.4% vs. III=78.8%, p=0.89). Reductions in rates of incision and drainage (Pre=7.5% vs. Post=0.7%, p<0.01) were maintained (Phase-II=0% vs. III=1.3%, p=0.38), and follow-up consistently improved (Pre=43.4% vs. Post=95.7%, p<0.001; Phase-II=91.8% vs. III=98.8%, p=0.12). Reduced hospital admission (Pre=30.2% vs. Post=20.6%, p=0.25) and median length of stay [Pre=2 days (range=1-5) vs. Post=1 day (range=1-6), p=0.07] were not statistically significant.

Journal article

Modi H, Singh H, Yang G, Darzi A, Leff Det al., 2018, Neural correlates of stress resilience in the operating room, Journal of The American College of Surgeons, Vol: 227, Pages: e208-e208, ISSN: 1072-7515

IntroductionIntraoperative stressors can increase surgeons’ mental demands, precipitating technical performance decline and risking patient safety. However, the neural signatures of stress resilience among surgeons remain unknown. We aimed to compare activation in the prefrontal cortex (PFC)–important for attention and concentration–between residents demonstrating performance stability and those exhibiting performance decline when operating under time pressure.MethodsThirty-three surgical residents [median age (range) = 33 years (29 to 56), 27 males] performed a laparoscopic suturing task under ‘self-paced’ (no time restriction) and ‘time pressure’ (2-minute per knot time restriction) conditions. A composite deterioration score was calculated based on between-condition differences in technical performance, and subjects were divided into quartiles reflecting performance stability (Q1) and decline (Q4). Changes in oxygenated haemoglobin concentration (HbO2) measured at 24 prefrontal locations using functional near-infrared spectroscopy were compared between Q1 and Q4. Subjective workload was quantified using the Surgical Task Load Index (SURG-TLX).ResultsUnder time pressure, Q1 residents demonstrated task-induced increases in HbO2 in the bilateral ventrolateral PFC (VLPFC), whereas Q4 residents demonstrated HbO2 decreases. The amplitude of activation (ΔHbO2) was significantly greater in Q1 than Q4 in the bilateral VLPFC (left VLPFC: Q1=0.44±1.36μM, Q4=-0.03±1.83μM; right VLPFC: Q1=0.49±1.70μM, Q4=-0.32±2.00μM). There were no significant between-group differences in SURG-TLX scores.ConclusionsResilience to intraoperative stress is associated with sustained prefrontal activation indicating preserved attention and concentration. In contrast, sensitivity to stress is marked by prefrontal deactivation suggesting task disengagement. Future work will aim to develop interventions that recr

Journal article

Singh H, Modi HN, Ranjan S, Dilley J, Airantzis D, Yang G, Darzi A, Leff Det al., 2018, Robotic surgery improves technical performance and enhances prefrontal activation during high temporal demand, Annals of Biomedical Engineering, Vol: 46, Pages: 1621-1636, ISSN: 0090-6964

Robotic surgery may improve technical performance and reduce mental demands compared to laparoscopic surgery. However, no studies have directly compared the impact of robotic and laparoscopic techniques on surgeons’ brain function. This study aimed to assess the effect of the operative platform (robotic surgery or conventional laparoscopy) on prefrontal cortical activation during a suturing task performed under temporal demand. Eight surgeons (mean age ± SD = 34.5 ± 2.9 years, male:female ratio = 7:1) performed an intracorporeal suturing task in a self-paced manner and under a 2 min time restriction using conventional laparoscopic and robotic techniques. Prefrontal activation was assessed using near-infrared spectroscopy, subjective workload was captured using SURG-TLX questionnaires, and a continuous heart rate monitor measured systemic stress responses. Task progression scores (au), error scores (au), leak volumes (mL) and knot tensile strengths (N) provided objective assessment of technical performance. Under time pressure, robotic suturing led to improved technical performance (median task progression score: laparoscopic suturing = 4.5 vs. robotic suturing = 5.0; z = − 2.107, p = 0.035; median error score: laparoscopic suturing = 3.0 mm vs. robotic suturing = 2.1 mm; z = − 2.488, p = 0.013). Compared to laparoscopic suturing, greater prefrontal activation was identified in seven channels located primarily in lateral prefrontal regions. These results suggest that robotic surgery improves performance during high workload conditions and is associated with enhanced activation in regions of attention, concentration and task engagement.

Journal article

Leff DR, de Silva T, Henry F, Thiruchelvam P, Hadjiminas D, Al-Mufti R, Hogben K, Hunter J, Wood S, Jalalli Net al., 2018, Streamlining decision making in contralateral risk-reducing mastectomy: impact of PREDICT and BOADICEA computations, Annals of Surgical Oncology, Vol: 25, Pages: 3057-3063, ISSN: 1068-9265

Introduction.Patients with sporadic breast cancer (BC)have low contralateral breast cancer risk (CLBCR;approximately 0.7% per annum) and contralateral pro-phylactic mastectomy (CPM) offers no survival advantage.CPM with autologous reconstruction (AR) has majormorbidity and resource implications.Objective.The aim of this study was to review the impactof PREDICT survival estimates and lifetime CLBCRscores on decision making for CPM in patients with uni-lateral BC.Methods.Ofn= 272 consecutive patients undergoingmastectomy and AR, 252 were included. Five- and 10-yearsurvival was computed with the PREDICT(V2) onlineprognostication tool, using age and clinicopathologicalfactors. Based on family history (FH) and tumor biology,CLBCR was calculated using validated BODICEA web-based software. Survival scores were correlated againstCLBCR estimates to identify patients receiving CPM with‘low’ CLBCR (\30% lifetime risk) and poor prognosis (5-year survival\80%). Patients with ‘high’ CLBCRreceiving unilateral mastectomy (UM) were similarlyidentified (UK National Institute of Health and CareExcellence [NICE] criteria for CPM,C30% lifetime BCrisk). Justifications motivating CPM were investigated.Results.Of 252 patients, 215 had UM and 37 had bilateralmastectomy and AR. Only 23 (62%) patients receivingCPM fulfilled the NICE criteria. Of 215 patients, 5 (2.3%)failed to undergo CPM despite high CLBCR and goodprognosis. CPMs were performed, at the patient’s request,for no clear justification (n= 8), contralateral non-invasivedisease, and/or FH (n= 5), FH alone (n= 4) and ipsilateralcancer recurrence-related anxiety (n= 3).Conclusion.In the absence of prospective risk estimatesof CLBCR and prognosis, certain patients receive CPMand reconstruction despite modest CLBCR, yet a propor-tion of patients with good prognoses and substantial riskare not undergoing CPM

Journal article

Cutress RI, McIntosh SA, Potter S, Goyal A, Kirwan CC, Harvey J, Francis A, Carmichael AR, Vidya R, Vaidya JS, Fairbrother P, Benson JR, Reed MWR, Basu NN, Benson JR, Bundred NJ, Carmichael AR, Coombs N, Cutress RI, Dickson J, Dixon JM, Douek M, Fairbrother P, Francis A, Goyal A, Harcourt D, Harvey J, Holcombe C, Horsnell J, Iqbal FM, Khan LR, Kirwan CC, Leff DR, Maxwell AJ, McIntosh SA, Paraskeva N, Potter S, Rattay T, Reed MWR, Sami AS, Singer J, St John ER, Subramanian A, Tobias JS, Touqan N, Vaidya JS, Vidya R, Winters ZEet al., 2018, Opportunities and priorities for breast surgical research, The Lancet Oncology, Vol: 19, Pages: e521-e533, ISSN: 1470-2045

Journal article

Singh H, Modi H, Yang G, Darzi A, Leff Det al., 2018, Impact of escalating cognitive workload and temporal demands on surgeons cognitive function, 2nd International Neuroergonomics Conference, Publisher: Frontiers Media, ISSN: 1662-5161

Conference paper

Singh H, Modi H, Darzi A, Leff Det al., Robotic Surgery Improves Technical Performance and Enhances Prefrontal Activation During High Temporal Demand, Ara Darzi

Athanasiou Award Presentation

Conference paper

Osborne-Grinter M, Patel R, Modi H, Singh H, Darzi A, Leff Det al., Enhancing Surgical Performance Through Mental Rehearsal: An fNIRS Study, society of functional Near Infra-red Spectroscopy, Biennial meeting of society of functional Near Infra-red Spectroscopy (fNIRS-2018)

Background: Mental rehearsal (MR) is the cognitive rehearsal of a skill without movement to produce genuine sensory experiences. Mandates for new approaches to surgical skill acquisition have led to increased interest in MR as a method of practical learning supplementation. However, the neurophysiological mechanisms underpinning the psychomotor benefits of MR are poorly understood.Objective: To delineate the neural mechanisms that underpin mental imagery-related improvements in surgical performance.Methods: Twelve surgical trainees performed a laparoscopic suturing (LS) task (pre-intervention) followed by randomization to either MR (n=6) or textbook reading (TR; n=6). The LS task was repeated (post-intervention). Subjective workload was quantified using the Surgical Task Load Index and Spielberg State-Trait Anxiety Index. Mental imagery ability was assessed using a mental imagery questionnaire. Continuous heart rate (HR) monitoring captured stress responses. Cortical activation was recorded with optical neuroimaging (ETG-4000, Hitachi Medical Corp., Japan). Technical skill was assessed using progression scores (au), performance scores (units) and leak volumes (mL). Results: There were no baseline differences in demographics, mental imagery ability or laparoscopic performance between the two groups. MR significantly improved post-intervention performance scores (53.10 ± 28.00 a.u. vs. -61.32 ± 40.78 a.u., p=0.04) and reduced leak volume (3.48 ±0.44ml vs. 4.81 ± 0.61ml, p=0.04) when compared to TR. MR also led to significant improvement in subjective imagery ability (41.50 ± 4.59 a.u. vs 31.17 ± 9.11 a.u, P=0.009). There were no differences in subjective or objective stress measures between the two groups. Cortical activation was defined by a significant (p < 0.05) rise in oxygenated haemoglobin with a concurrent fall in deoxygenated haemoglobin. During MR, activation was demonstrated in the left supplementary motor area (S

Conference paper

Fisher R, Muthuswamy K, Petrou F, Mavroveli S, Thiruchelvam P, Fisher C, Leff Det al., 2018, The impact of the American College of Surgeons Oncology Group Z0011 Trial on axillary lymph node dissection cases worldwide: A systematic review, 19th Annual Meeting of the American-Society-of-Breast-Surgeons, Publisher: Springer (part of Springer Nature), Pages: 434-434, ISSN: 1068-9265

Conference paper

Deligianni F, Singh H, Modi H, Darzi A, Leff D, Yang GUANGet al., Expertise Related Disparity in Prefrontal-Motor Brain Connectivity, Hamlyn Symposium on Medical Robotics

Conference paper

Muthuswamy K, Fisher R, Petrou F, Mavroveli S, Leff Det al., 2018, Specialist trainee experiences in axillary lymph node dissection in a post-Z11-era survey indicates declining exposure and confidence, 19th Annual Meeting of the American-Society-of-Breast-Surgeons, Publisher: SPRINGER, Pages: 393-394, ISSN: 1068-9265

Conference paper

Thiruchelvam P, Fisher C, Leff DR, Domcheck Set al., 2018, Pervasive genetic testing, Lancet, Vol: 391, Pages: 2089-2091, ISSN: 0140-6736

Journal article

Erridge S, Chidambaram S, Leff DR, Purkayastha Set al., 2018, Validating touch surgery for training in laparoscopic cholecystectomies: a randomised controlled trial, Annual Meeting of the Society-of-Academic-and-Research-Surgery (SARS), Publisher: Wiley, Pages: 30-30, ISSN: 1365-2168

Background: Surgical training has traditionally involved teaching trainees in the operating theatre. However, this method is associated with longer operating times and complications, which is cost-inefficient and exposes patients to errors. Simulation modalities such as Touch Surgery, which utilises cognitive task analysis (CTA), have been designed to overcome these issues.Methods: Participants performed a laparoscopic cholecystectomy procedure using a box simulator and porcine liver and gall bladder. They were randomly allocated to either the control or the intervention group. Each group received the same preparation prior to intervention, including a 10-minute introduction to laparoscopic equipment and a 15-minute educational tutorial on laparoscopic cholecystectomies. The participants then received CTA training via either Touch Surgery (intervention) or via written information (control).Results: 40 participants were recruited to take part in the study and randomly assigned to either intervention (n=22) or control (n=18). There was no significant difference between age (p=0.320), year of medical school (p=0.322), handedness (p=1.000) or gender (p=0.360) of the groups. The overall mean performance score was higher for intervention (41.9±22.5) than control (24.7±19.6; p=0.016). The intervention group had consistently higher scores throughout all intraoperative segments although this was not statistically significant (p>0.050). Conclusion: This study shows that Touch Surgery is effective for providing cognitive training in laparoscopic cholecystectomies to medical students. It is likely that this effect will be seen across modules and other platforms that utilise CTA alongside high fidelity animation. Further work is necessary to extend this to other surgical procedures for evaluating its longitudinal effectiveness.Take Home Message: CTA training provided via high fidelity simulation is an effective and inexpensive method of providing surgical educat

Conference paper

Modi HN, Singh H, Yang G, Darzi A, Leff DRet al., Robotic surgery improves attention and concentration during times of intraoperative temporal stress, Association of Surgeons of Great Britain & Ireland International Surgical Congress, Publisher: Wiley, ISSN: 1365-2168

Conference paper

Leiloglou M, Qi J, Rees Whippey D, Curtis A, Price C, Copner N, Martin-Gonzalez P, Hanna G, Darzi A, Leff D, Elson Det al., Guiding Fluorescence-Augmented Imaging System for Breast Cancer Surgery, BMES Annual Meeting

Conference paper

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