Guy's and St Thomas' NHS Foundation Trust

About: Guy's and St Thomas' NHS Foundation Trust is a healthcare organization based out in London, United Kingdom. It is known for research contribution in the topics: Population & Medicine. The organization has 7686 authors who have published 9631 publications receiving 399353 citations. The organization is also known as: Guy's and St Thomas' National Health Service Foundation Trust & Guy's and St Thomas' National Health Service Trust.

Effectiveness of the HoloLens mixed-reality headset in minimally invasive surgery: a simulation-based feasibility study.

Abstract: The advent of Virtual Reality technologies presents new opportunities for enhancing current surgical practice. Studies suggest that current techniques in endoscopic surgery are prone to disturbance of a surgeon’s visual-motor axis, influencing performance, ergonomics and iatrogenic injury rates. The Microsoft® HoloLens is a novel head-mounted display that has not been explored within surgical innovation research. This study aims to evaluate the HoloLens as a potential alternative to conventional monitors in endoscopic surgery. This prospective, observational and comparative study recruited 72 participants consisting of novices (n = 28), intermediate-level (n = 24) and experts (n = 20). Participants performed ureteroscopy, within an inflatable operating environment, using a validated training model and the HoloLens mixed-reality device as a monitor. Novices also completed the assigned task using conventional monitors; whilst the experienced groups did not, due to their extensive familiarity. Outcome measures were procedural completion time and performance evaluation (OSATS) score. A final evaluation survey was distributed amongst all participants. The HoloLens facilitated improved outcomes for procedural times (absolute difference, − 73 s; 95% CI − 115 to − 30; P = 0.0011) and OSAT scores (absolute difference, 4.1 points; 95% CI 2.9–5.3; P < 0.0001) compared to conventional monitors. Feedback evaluation demonstrated 97% of participants agreed or strongly agreed that the HoloLens will have a role in surgical education (mean rating, 4.6 of 5; 95% CI 4.5–4.8). Furthermore, 95% of participants agreed or strongly agreed that the HoloLens is feasible to introduce clinically and will have a role within surgery (mean rating, 4.4 of 5; 95% CI 4.2–4.5). This study demonstrates that the device facilitated improved outcomes of performance in novices and was widely accepted as a surgical visual aid by all groups. The HoloLens represents a feasible alternative to the conventional setup, possibly by aligning the surgeon’s visual-motor axis.

Defining the optimal method for measuring baseline metabolic tumour volume in diffuse large B cell lymphoma.

Abstract: Metabolic tumour volume (MTV) is a promising prognostic indicator in diffuse large B cell lymphoma (DLBCL). Optimal thresholds to divide patients into ‘low’ versus ‘high’ MTV groups depend on clinical characteristics and the measurement method. The aim of this study was to compare in consecutive unselected patients with DLBCL, different software algorithms and published methods of MTV measurement using FDG PET. Pretreatment MTV was measured on 147 patients treated at Guy's and St Thomas’ Hospital. We compared 3 methods: SUV ≥2.5, SUV ≥41% of maximum SUV and SUV ≥ mean liver uptake (PERCIST) and compared 2 software programs for measuring SUV ≥2.5; in-house ‘PETTRA’ software and Hermes commercial software. There was strong correlation between MTV using the 4 methods, although derived thresholds were very different for the 41% method. Optimal cut-offs for predicting PFS ranged from 166–400cm3. All methods predicted survival with similar accuracy. 5y-PFS was 83–87% vs. 42–44% and 5y-OS was 85–89% vs. 55–58% for the low- and high-MTV groups, respectively. Interobserver variation in 50 patients showed excellent agreement, though variation was lowest using the SUV ≥ 2.5 method. The 41% method was the most complex and took the longest time. All methods predicted PFS and OS with similar accuracy, but the derived cut-off separating good from poor prognosis varied markedly depending on the method. The choice of the optimal method should rely primarily on prognostic value, but for clinical use needs to take account of ease of use and reproducibility. In this study, all methods predicted prognosis, but SUV ≥ 2.5 had the best inter-observer agreement and was easiest to apply.

The relationship among thromboelastography, hemostatic variables, and bleeding after cardiopulmonary bypass surgery in children.

Abstract: BACKGROUND: Mediastinal bleeding is common after pediatric cardiopulmonary bypass (CPB) surgery. Thromboelastography (TEG ® ) may predict bleeding and provide insight into likely mechanisms. We aimed to (a) compare perioperative temporal profiles of TEG ® and laboratory hemostatic variables between patients with significant hemorrhage (BLEED) and those without (CONTROL), (b) investigate the relationship between TEG ® variables and routine hemostatic variables, and (c) develop a model for prediction of bleeding. METHODS: TEG ® and laboratory hemostatic variables were measured prospectively at 8 predefined times for 50 children weighing <20 kg undergoing CPB. RESULTS: Patients who bled demonstrated different TEG ® profiles than those who did not. This was most apparent after protamine administration and was partly attributable to inadequate heparin reversal, but was also associated with a significantly lower nadir in mean (SD) fibrinogen for the BLEED group compared with CONTROL group: 0.44 (0.18) and 0.71 (0.40) g/L, respectively (P = 0.01). Significant nonlinear relationships were found between the majority of TEG ® and laboratory hemostatic variables. The strongest relationship was between the maximal amplitude and the platelet-fibrinogen product (logarithmic r 2 = 0.71). Clot strength decreased rapidly when (a) fibrinogen concentration was <1 g/L, (b) platelets were <120 × 10 9 /L, and (c) platelet-fibrinogen product was <100. A 2-variable model including the activated partial thromboplastin time at induction of anesthesia and TEG ® mean amplitude postprotamine discriminated well for subsequent bleeding (C statistic 0.859). CONCLUSIONS: Hypofibrinogenemia and inadequate heparin reversal are 2 important factors contributing to clot strength and perioperative hemorrhage after pediatric CPB. TEG ® may be a useful tool for predicting and guiding early treatment of mediastinal bleeding in this group.

Functional outcome measures for NF1-associated optic pathway glioma clinical trials

Abstract: Objective: The goal of the Response Evaluation in Neurofibromatosis and Schwannomatosis Visual Outcomes Committee is to define the best functional outcome measures for future neurofibromatosis type 1 (NF1)-associated optic pathway glioma (OPG) clinical trials. Methods: The committee considered the components of vision, other ophthalmologic parameters affected by OPG, potential biomarkers of visual function, and quality of life measures to arrive at consensus-based, evidence-driven recommendations for objective and measurable functional endpoints for OPG trials. Results: Visual acuity (VA) assessments using consistent quantitative testing methods are recommended as the main functional outcome measure for NF1-OPG clinical trials. Teller acuity cards are recommended for use as the primary VA endpoint, and HOTV as a secondary endpoint once subjects are old enough to complete it. The optic disc should be assessed for pallor, as this appears to be a contributory variable that may affect the interpretation of VA change over time. Given the importance of capturing patient-reported outcomes in clinical trials, evaluating visual quality of life using the Children’s Visual Function Questionnaire as a secondary endpoint is also proposed.