163 results found
Modi HN, SIngh H, Orihuela-Espina F, et al., 2017, Temporal stress in the operating room: brain engagement promotes "coping" and disengagement prompts "choking", Annals of Surgery, Vol: 267, Pages: 683-691, ISSN: 1528-1140
Objective:To investigate the impact of time pressure (TP) on prefrontalactivation and technical performance in surgical residents during a laparo-scopic suturing task.Background:Neural mechanisms enabling surgeons to maintain perform-ance and cope with operative stressors are unclear. The prefrontal cortex(PFC) is implicated due to its role in attention, concentration, and perform-ance monitoring.Methods:A total of 33 residents [Postgraduate Year (PGY)1 – 2¼15,PGY3– 4¼8, and PGY5¼10] performed a laparoscopic suturing taskunder ‘‘self-paced’’ (SP) and ‘‘TP’’ conditions (TP¼maximum 2 minutes perknot). Subjective workload was quantified using the Surgical Task LoadIndex. PFC activation was inferred using optical neuroimaging. Technicalskill was assessed using progression scores (au), error scores (mm), leakvolumes (mL), and knot tensile strengths (N).Results:TP led to greater perceived workload amongst all residents (meanSurgical Task Load Index score SD: PGY1 – 2: SP¼160.3 24.8 vs TP¼202.1 45.4,P<0.001; PGY3 – 4: SP¼123.0 52.0 vs TP¼172.5 43.1,P<0.01; PGY5: SP¼105.8 55.3 vs TP¼159.1 63.1,P<0.05).Amongst PGY1– 2 and PGY3– 4, deterioration in task progression, errorscores and knot tensile strength (P<0.05), and diminished PFC activationwas observed under TP. In PGY5, TP resulted in inferior task progression anderror scores (P<0.05), but preservation of knot tensile strength. Furthermore,PGY5 exhibited less attenuation of PFC activation under TP, and greateractivation than either PGY1 – 2 or PGY3 – 4 under both experimental con-ditions (P<0.05).Conclusions:Senior residents cope better with temporal demands and exhibitgreater technical performance stability under pressure, possibly due to
Gambini J, Quinn T, Vila R, et al., 2017, Upgraded portable Indocyanine Green (ICG) detection system - towards Image Guided Cancer Surgery, Annual Meeting of the Society-of-Nuclear-Medicine-and-Molecular-Imaging (SNMMI), Publisher: SOC NUCLEAR MEDICINE INC, ISSN: 0161-5505
St John E, White E, Balog J, et al., 2017, The intelligent knife for detection of invasive breast cancer at radial margins: An intraoperative feasibility trial, Publisher: SPRINGER, Pages: 194-195, ISSN: 1068-9265
Thiruchelvam P, Hadjiminas D, Cleator S, et al., 2017, Primary Radiotherapy And DIEP flAp reconstruction: The PRADA study, American Society of Breast Surgeons Annual Meeting, Publisher: SPRINGER, Pages: 199-200, ISSN: 1068-9265
Leff DR, St John ER, Takats Z, 2017, Reducing the Margins of Error During Breast-Conserving Surgery Disruptive Technologies or Traditional Disruptions?, JAMA SURGERY, Vol: 152, Pages: 517-518, ISSN: 2168-6254
Vyas K, hughes M, leff DANIEL, et al., 2017, Methylene-blue aided rapid confocal laser endomicroscopy of breast cancer, Journal of Biomedical Optics, Vol: 22, ISSN: 1083-3668
Breast conserving surgery allows complete tumor resection while maintaining acceptable cosmesis for patients. Safe and rapid intraoperative margin assessment during the procedure is important to establish the completeness of tumor excision and minimizes the need for reoperation. Confocal laser endomicroscopy has demonstrated promise for real-time intraoperative margin assessment using acriflavine staining, but it is not approved for routine in-human use. We describe a custom high-speed line-scan confocal laser endomicroscopy (LS-CLE) system at 660 nm that enables high-resolution histomorphological imaging of breast tissue stained with methylene-blue, an alternative fluorescent stain for localizing sentinel nodes during breast surgery. Preliminary imaging results on freshly excised human breast tissue specimens are presented, demonstrating the potential of methylene-blue aided rapid LS-CLE to determine the oncological status of surgical margins in-vivo.
Nabavi E, Qi J, Leiloglou M, et al., 2017, Preliminary Studies Of Simultaneous RGB And NIR Fluorescence Imaging Of Ex Vivo Human Breast Tissue Using Indocyanine Green (ICG), CLEO Pacific Rim
Leff DR, Yongue G, Vlaev I, et al., 2017, "Contemplating the next maneuver": functional neuroimaging reveals intraoperative decision-making strategies, Annals of Surgery, Vol: 265, Pages: 320-330, ISSN: 1528-1140
OBJECTIVE: To investigate differences in the quality, confidence, and consistency of intraoperative surgical decision making (DM) and using functional neuroimaging expose decision systems that operators use. SUMMARY BACKGROUND DATA: Novices are hypothesized to use conscious analysis (effortful DM) leading to activation across the dorsolateral prefrontal cortex, whereas experts are expected to use unconscious automation (habitual DM) in which decisions are recognition-primed and prefrontal cortex independent. METHODS: A total of 22 subjects (10 medical student novices, 7 residents, and 5 attendings) reviewed simulated laparoscopic cholecystectomy videos, determined the next safest operative maneuver upon video termination (10 s), and reported decision confidence. Video paradigms either declared ("primed") or withheld ("unprimed") the next operative maneuver. Simultaneously, changes in cortical oxygenated hemoglobin and deoxygenated hemoglobin inferring prefrontal activation were recorded using Optical Topography. Decision confidence, consistency (primed vs unprimed), and quality (script concordance) were assessed. RESULTS: Attendings and residents were significantly more certain (P < 0.001), and decision quality was superior (script concordance: attendings = 90%, residents = 78.3%, and novices = 53.3%). Decision consistency was significantly superior in experts (P < 0.001) and residents (P < 0.05) than novices (P = 0.183). During unprimed DM, novices showed significant activation of the dorsolateral prefrontal cortex, whereas this activation pattern was not observed among residents and attendings. During primed DM, significant activation was not observed in any group. CONCLUSIONS: Expert DM is characterized by improved quality, consistency, and confidence. The findings imply attendings use a habitual decision system, whereas novices use an effortful approach under uncertainty. In the presence of operative cues (primes), novices disengage
Qi J, Nabavi E, Hu Y, et al., 2017, A Light‐weight Near Infrared Fluorescence Endoscope Based On A Single Color Camera: A Proof‐of‐concept Study, CLEO Pacific Rim
Qi J, Nabavi E, Hu Y, et al., 2017, A light-weight near infrared fluorescence endoscope based on a single color camera: A proof-of-concept study
© 2018 Optics InfoBase Conference Papers. All rights reserved. Here we demonstrated a light-weight near infrared fluorescence endoscope based on a low-cost single color camera to perform real time white light and fluorescence imaging, thanks to advances in image sensors and electronically controllable LED light sources. We further explored frame interpolation to facilitate the reduction of frame rate of this endoscope system, compared to a typical dual camera based NIRF endoscope system.
Modi HN, Leff DR, Singh H, et al., 2016, Cognitive mechanisms of workload-related performance decline in surgical residents, American College of Surgeons Clinical Congress 2016, Publisher: Elsevier, Pages: S124-S125, ISSN: 1072-7515
Modi HN, Singh H, Athanasiou T, et al., 2016, Random effect modelling of prefrontal cortical haemodynamics to determine the influence of surgical expertise on executive control during temporal stress in the operating room, The Society for Functional Near-Infrared Spectroscopy, Publisher: fNIRS
Modi HN, Leff D, Singh H, et al., 2016, Time in training does not predict performance deterioration under pressure, Association for Medical Education in Europe, Publisher: AMEE
Modi HN, Leff DR, Singh H, et al., 2016, Temporal Demands Increase Workload and Degrade Surgical Performance, International Surgical Congress of the Association of Surgeons of Great Britain and Ireland, Publisher: Wiley, Pages: 52-53, ISSN: 1365-2168
St John ER, Al-Khudairi R, Ashrafian H, et al., 2016, Diagnostic accuracy of intraoperative techniques for margin assessment in breast cancer surgery: a meta-analysis, Annals of Surgery, Vol: 265, Pages: 300-310, ISSN: 1528-1140
OBJECTIVE: The aim of this study was to conduct a systematic review and meta-analysis to clarify the diagnostic accuracy of intraoperative breast margin assessment (IMA) techniques against which the performance of emerging IMA technologies may be compared. SUMMARY OF BACKGROUND DATA: IMA techniques have failed to penetrate routine practice due to limitations, including slow reporting times, technical demands, and logistics. Emerging IMA technologies are being developed to reduce positive margin and re-excision rates and will be compared with the diagnostic accuracy of existing techniques. METHOD: Studies were identified using electronic bibliographic searches up to January 2016. MESH terms and all-field search terms included "Breast Cancer" AND "Intraoperative" AND "Margin." Only clinical studies with raw diagnostic accuracy data as compared with final permanent section histopathology were included. A bivariate model for diagnostic meta-analysis was used to attain overall pooled sensitivity and specificity. RESULTS: Eight hundred thirty-eight unique studies revealed 35 studies for meta-analysis. Pooled sensitivity (Sens), specificity (Spec), and area under the receiver operating characteristic curve (AUROC) values were calculated per group (Sens, Spec, AUROC): frozen section = 86%, 96%, 0.96 (n = 9); cytology = 91%, 95%, 0.98 (n = 11); intraoperative ultrasound = 59%, 81%, 0.78 (n = 4); specimen radiography = 53%, 84%, 0.73 (n = 9); optical spectroscopy = 85%, 87%, 0.88 (n = 3). CONCLUSIONS: Pooled data suggest that frozen section and cytology have the greatest diagnostic accuracy. However, these methods are resource intensive and turnaround times for results have prevented widespread international adoption. Emerging technologies need to compete with the diagnostic accuracy of existing techniques while offering advantages in terms of speed, cost, and reliability.
Modi HN, Singh H, Yang GZ, et al., 2016, “Coping or choking”: sustained prefrontal activation and improved laparoscopic performance under time pressure, 9th Hamlyn Symposium on Medical Robotics
Modi HN, Singh H, Orihuela-Espina F, et al., 2016, Cortical haemodynamic changes associated with high and low cognitive demand in surgeons, 22nd Annual Meeting of the Organisation for Human Brain Mapping, Publisher: Organization for Human Brain Mapping
Boshier PRB, Sayers R, Hadjiminas D, et al., 2016, Systemic inflammatory response syndrome in a patient diagnosed with high grade inflammatory triple negative breast cancer: a case report of a potentially rare paraneoplastic syndrome, Experimental Hematology and Oncology, Vol: 5, ISSN: 2162-3619
BackgroundInflammatory breast cancer is a complex pathological entity associated with poor outcomes. This loco-regional disease is characterised by a rapid clinical course in the presence breast erythema and infiltration of dermal lymphatics by tumours cells. Herein we describe a case of inflammatory breast cancer with a rare presentation and disease course defined by a profound systemic inflammatory response in the absence of an infective cause.Case presentationThe patient presented with pyrexia and malaise following a recent tissue diagnosis of inflammatory breast cancer. At the time of admission the patient demonstrated clinical features of the systemic inflammatory response syndrome (SIRS) in the presence of a negative septic screen. Her condition deteriorated despite systemic broad spectrum intravenous antibiotics and she underwent surgical debulking of a 180 × 135 × 100 mm (821 g) primary tumour composed of oedematous, friable and haemorrhagic tissue (pT4,N1a,M0; oestrogen/progesterone/HER-2 receptor negative). Following surgery, the clinical picture dramatically improved with cessation of SIRS and normalisation of inflammatory markers. After 4 weeks the patient required readmission to hospital due to recurrent SIRS and negative septic screen. The patient received treatment with systemic chemotherapy showing transient clinical improvement and suppression of SIRS. Despite on going chemotherapy, systemic antibiotics and a trial of steroid therapy the patient died 5 months after her initial presentation to hospital. At the time of death she demonstrated persistent SIRS with elevated inflammatory markers.ConclusionThis is the first case report of inflammatory breath cancer associated with SIRS in the absence of clinically confirmed infection. Important learning points highlighted by this case are: (a) recognition of the diagnostic and therapeutic uncertainties that still exist in the context of inflammatory breast cancer; (b) appreciation of the potent
Singh H, modi H, Yang GZ, et al., 2016, A surgeon’s brain switch: cortical dynamics of cognitive load in surgeons, Publisher: Graz University of Technology, Pages: 163-163
Andreu-Perez J, Leff DR, Shetty K, et al., 2016, Disparity in frontal lobe connectivity on a complex bimanual motor task aids in classification of operator skill level., Brain Connectivity, Vol: 6, Pages: 375-388, ISSN: 2158-0022
Objective metrics of technical performance (e.g., dexterity, time, and path length) are insufficient to fully characterize operator skill level, which may be encoded deep within neural function. Unlike reports that capture plasticity across days or weeks, this articles studies long-term plasticity in functional connectivity that occurs over years of professional task practice. Optical neuroimaging data are acquired from professional surgeons of varying experience on a complex bimanual coordination task with the aim of investigating learning-related disparity in frontal lobe functional connectivity that arises as a consequence of motor skill level. The results suggest that prefrontal and premotor seed connectivity is more critical during naïve versus expert performance. Given learning-related differences in connectivity, a least-squares support vector machine with a radial basis function kernel is employed to evaluate skill level using connectivity data. The results demonstrate discrimination of operator skill level with accuracy ≥0.82 and Multiclass Matthew's Correlation Coefficient ≥0.70. Furthermore, these indices are improved when local (i.e., within-region) rather than inter-regional (i.e., between-region) frontal connectivity is considered (p = 0.002). The results suggest that it is possible to classify operator skill level with good accuracy from functional connectivity data, upon which objective assessment and neurofeedback may be used to improve operator performance during technical skill training.
Shetty K, Leff DR, Orihuela-Espina F, et al., 2016, Persistent Prefrontal Engagement Despite Improvements in Laparoscopic Technical Skill, JAMA Surgery, Vol: 151, Pages: 682-684, ISSN: 2168-6262
Teaching and assessment of laparoscopic skills are currently essential components of surgical training. The Fundamentals of Laparoscopic Surgery (FLS) is a widely adopted training program based on expert-derived benchmarks; technical skills are assessed and completion is a mandatory criterion for general surgery board certification in the United States.1 However, is attainment of technical proficiency synonymous with being a safe surgeon? Intraoperative errors persist and are thought to be related to errors in cognition2 as opposed to technical failure per se. The prefrontal cortex (PFC) is a brain region associated with attention and executive function serving as a scaffold to support novel task demands during effortful unrefined performance.3 Studies examining cortical correlates of technical skills acquisition have observed predictable attenuation in PFC response alongside improvement in technical performance4,5; however, this has not been adequately tested for challenging laparoscopic skills.
Thiruchelvam P, Cleator S, Wood S, et al., 2016, Primary Radiotherapy and DIEP [Deep Inferior Epigastric Perforator] Flap Reconstruction (PRADA) Study: Findings From the Pilot Study, 17th Annual Meeting of the American-Society-of-Breast-Surgeons, Publisher: SPRINGER, Pages: 159-160, ISSN: 1068-9265
St John ER, Al-Khudairi R, Balog J, et al., 2016, Rapid evaporative ionisation mass spectrometry towards real time intraoperative oncological margin status determination in breast conserving surgery, 38th Annual CTRC-AACR San Antonio Breast Cancer Symposium, Publisher: American Association for Cancer Research, Pages: P2-12-20-P2-12-20, ISSN: 1538-7445
St John ER, Al-Khudairi R, Balog J, et al., 2016, Abstract P2-12-20: rapid evaporative ionisation mass spectrometry towards real time intraoperative oncological margin status determination in breast conserving surgery, 38th Annual CTRC-AACR San Antonio Breast Cancer Symposium, Publisher: American Association for Cancer Research, ISSN: 1538-7445
Modi HN, Leff DR, Singh H, et al., 2016, The influence of cognitive load on technical ability among surgical trainees, Association of Surgeons in Training International Conference
Leff DR, Shetty K, Yang GZ, et al., Persistent Attentional Demands Despite Laparoscopic Skills Acquisition, JAMA Surgery, ISSN: 2168-6262
Flindall IR, Leff DR, Pucks N, et al., 2016, The Preservation of Cued Recall in the Acute Mentally Fatigued State: A Randomised Crossover Study., World Journal of Surgery, Vol: 40, Pages: 56-65, ISSN: 1432-2323
PURPOSE: The objective of this study is to investigate the impact of acute mental fatigue on the recall of clinical information in the non-sleep-deprived state. Acute mental fatigue in the non-sleep-deprived subject is rarely studied in the medical workforce. Patient handover has been highlighted as an area of high risk especially in fatigued subjects. This study evaluates the deterioration in recall of clinical information over 2 h with cognitively demanding work in non-sleep-deprived subjects. METHOD: A randomised crossover study involving twenty medical students assessed free (presentation) and cued (MCQ) recall of clinical case histories at 0 and 2 h under low and high cognitive load using the N-Back task. Acute mental fatigue was assessed through the Visual Analogue Scale, Stanford Scale and NASA-TLX Mental Workload Rating Scale. RESULTS: Free recall is significantly impaired by increased cognitive load (p < 0.05) with subjects demonstrating perceived mental fatigue during the high cognitive load assessment. There was no significant difference in the amount of information retrieved by cued recall under high and low cognitive load conditions (p = 1). DISCUSSION: This study demonstrates the loss of clinical information over a short time period involving a mentally fatiguing, high cognitive load task. Free recall for the handover of clinical information is unreliable. Memory cues maintain recall of clinical information. This study provides evidence towards the requirement for standardisation of a structured patient handover. The use of memory cues (involving recognition memory and cued recall methodology) would be beneficial in a handover checklist to aid recall of clinical information and supports evidence for their adoption into clinical practice.
Leff DR, Petrou G, Mavroveli S, et al., 2015, Validation of an oncoplastic breast simulator for assessment of technical skills in wide local excision., British Journal of Surgery, Vol: 103, Pages: 207-217, ISSN: 1365-2168
BACKGROUND: Simulation enables safe practice and facilitates objective assessment of technical skills. However, simulation training in breast surgery is rare and assessment remains subjective. The primary aim was to evaluate the construct validity of technical skills assessments in wide local excision (WLE). METHODS: Surgeons of different grades performed a WLE of a 25-mm palpable tumour on an in-house synthetic breast simulator. Procedures were videotaped (blinded), reviewed retrospectively, and independently rated against a procedure-specific global rating scale by two consultant breast surgeons. Specimen radiographs were obtained and the macroscopic distance from the 'tumour' edge to the resection margin was recorded in four cardinal directions. Expert consensus was used to construct an Oncoplastic Deviation Score (ODS), assigning points for excessively wide (more than 10 mm) and, conversely, close (less than 5 mm) macroscopic margins. RESULTS: Thirty-four surgeons (12 consultant surgeons, 12 specialty trainees and 10 core trainees) participated in the study. Video-based rating scores varied hierarchically with operator expertise (P < 0·050). Inter-rater reliability was excellent (α ≥ 0·80, P < 0·050 for all scales), and inter-rater agreement was moderate (κ = 0·132-0·361, P < 0·050 for all scales). Statistically significant differences were observed on pairwise comparisons between each grade of surgeon in scores for 'exposure', 'skin flap development', 'glandular remodelling', 'skin closure' and 'final product review' (P < 0·050). Consultants received significantly fewer ODS points than specialty trainees (P = 0·012) and core trainees (P = 0·028). Compared with experts (median 9·0 mm), wider margins were observed amongst specialty trainees (median 12·0 mm) and narrower margins amongst core trainees (median 7·1 mm) (P = 0·001). CONCLUSION: Video r
Crewther BT, Shetty K, Jarchi D, et al., 2015, Skill acquisition and stress adaptations following laparoscopic surgery training and detraining in novice surgeons., Surgical Endoscopy, Vol: 30, Pages: 1961-2968, ISSN: 0930-2794
BACKGROUND: Surgical training and practice is stressful, but adaptive changes in the stress circuitry (e.g. perceptual, physiological, hormonal, neural) could support skill development. This work examined skill acquisition and stress adaptations in novice surgeons during laparoscopic surgery (LS) training and detraining. METHODS: Twelve medical students were assessed for skill performance after 2 h (BASE), 5 h (MID) and 8 h (POST) of LS training in weeks 1-3, and then after 4 weeks of no training (RETEST). The stress outcomes included state anxiety, perceived stress and workload, heart rate (HR), heart rate variability (HRV), and salivary testosterone and cortisol concentrations. Functional near-infrared spectroscopy was used to assess cortical oxygenation change, as a marker of prefrontal cortex (PFC) activity. RESULTS: Skill performance improved in every session from BASE (p < 0.01), with corresponding decreases in state anxiety, stress, workload, low- and high-frequency HRV in the MID, POST and/or RETEST sessions (p < 0.05). Left and right PFC were symmetrically activated within each testing session (p < 0.01). The stress and workload measures predicted skill performance and changes over time (p < 0.05), with state anxiety, mean HR and the HRV measures also showing some predictive potential (p < 0.10). CONCLUSIONS: A 3-week LS training programme promoted stress-related adaptations likely to directly, or indirectly, support the acquisition of new surgical skills, and many outcomes were retained after a 4-week period without further LS training. These results have implications for medical training and education (e.g. distributed training for skill development and maintenance, stress resource and management training) and highlighted possible areas for new research (e.g. longitudinal stress and skill profiling).
Leff DR, James D, Orihuela-Espina F, et al., 2015, The impact of expert visual guidance on trainee visual search strategy, visual attention and motor skills, Frontiers in Human Neuroscience, Vol: 9, ISSN: 1662-5161
Minimally invasive and robotic surgery changes the capacity for surgical mentors to guide their trainees with the control customary to open surgery. This neuroergonomic study aims to assess a “Collaborative Gaze Channel” (CGC); which detects trainer gaze-behaviour and displays the point of regard to the trainee. A randomised crossover study was conducted in which twenty subjects performed a simulated robotic surgical task necessitating collaboration either with verbal (control condition) or visual guidance with CGC (study condition). Trainee occipito-parietal (O-P) cortical function was assessed with optical topography (OT) and gaze-behaviour was evaluated using video-oculography. Performance during gaze-assistance was significantly superior [biopsy number: (mean ± SD): control=5·6±1·8 vs. CGC=6·6±2·0; p< 0.05] and was associated with significantly lower O-P cortical activity [∆HbO2 mMol x cm [median (IQR)] control = 2.5 (12.0) vs. CGC 0.63 (11.2), p < 0.001]. A random effect model confirmed the association between guidance mode and O-P excitation. Network cost and global efficiency and global efficiency were not significantly influenced by guidance mode. A gaze channel enhances performance, modulates visual search, and alleviates the burden in brain centres subserving visual attention and does not induce changes in the trainee's O-P functional network observable with the current OT technique. The results imply that through visual guidance, attentional resources may be liberated, potentially improving the capability trainees to attend to other safety critical events during the procedure.
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.