Imperial College London

MrHaniMarcus

Faculty of MedicineDepartment of Surgery & Cancer

Honorary Clinical Research Fellow
 
 
 
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hani.marcus10

 
 
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Paterson WingSt Mary's Campus

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Summary

 

Publications

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137 results found

Jashek-Ahmed F, Cabrilo I, Bal J, Sanders B, Grieve J, Dorward NL, Marcus HJet al., 2021, Intraoperative monitoring of visual evoked potentials in patients undergoing transsphenoidal surgery for pituitary adenoma: a systematic review, BMC Neurology, Vol: 21, ISSN: 1471-2377

BackgroundTranssphenoidal surgery is the gold standard for pituitary adenoma resection. Although rare, a serious complication of surgery is worsened vision post-operatively.ObjectiveTo determine whether, in patients undergoing transsphenoidal surgery for pituitary adenoma, intraoperative monitoring of visual evoked potentials (VEP) is a safe, reproducible, and effective technological adjunct in predicting postoperative visual function.MethodsThe PubMed and OVID platforms were searched between January 1993 and December 2020 to identify publications that (1) featured patients undergoing transsphenoidal surgery for pituitary adenoma, (2) used intraoperative optic nerve monitoring with VEP and (3) reported on safety or effectiveness. Reference lists were cross-checked and expert opinion sought to identify further publications.ResultsEleven studies were included comprising ten case series and one prospective cohort study. All employed techniques to improve reliability. No safety issues were reported. The only comparative study included described a statistically significant improvement in post-operative visual field testing when VEP monitoring was used. The remaining case-series varied in conclusion. In nine studies, surgical manipulation was halted in the event of a VEP amplitude decrease suggesting a widespread consensus that this is a warning sign of injury to the anterior optic apparatus.ConclusionsDespite limited and low-quality published evidence regarding intra-operative VEP monitoring, our review suggests that it is a safe, reproducible, and increasingly effective technique of predicting postoperative visual deficits. Further studies specific to transsphenoidal surgery are required to determine its utility in protecting visual function in the resection of complex pituitary tumours.

Journal article

Khan DZ, Ali AMS, Koh CH, Dorward NL, Grieve J, Layard Horsfall H, Muirhead W, Santarius T, Van Furth WR, Zamanipoor Najafabadi AH, Marcus HJet al., 2021, Skull base repair following endonasal pituitary and skull base tumour resection: a systematic review., Pituitary, Vol: 24, Pages: 698-713, ISSN: 1386-341X

PURPOSE: Postoperative cerebrospinal fluid rhinorrhoea (CSFR) remains a frequent complication of endonasal approaches to pituitary and skull base tumours. Watertight skull base reconstruction is important in preventing CSFR. We sought to systematically review the current literature of available skull base repair techniques. METHODS: Pubmed and Embase databases were searched for studies (2000-2020) that (a) reported on the endonasal resection of pituitary and skull base tumours, (b) focussed on skull base repair techniques and/or postoperative CSFR risk factors, and (c) included CSFR data. Roles, advantages and disadvantages of each repair method were detailed. Random-effects meta-analyses were performed where possible. RESULTS: 193 studies were included. Repair methods were categorised based on function and anatomical level. There was absolute heterogeneity in repair methods used, with no independent studies sharing the same repair protocol. Techniques most commonly used for low CSFR risk cases were fat grafts, fascia lata grafts and synthetic grafts. For cases with higher CSFR risk, multilayer regimes were utilized with vascularized flaps, gasket sealing and lumbar drains. Lumbar drain use for high CSFR risk cases was supported by a randomised study (Oxford CEBM: Grade B recommendation), but otherwise there was limited high-level evidence. Pooled CSFR incidence by approach was 3.7% (CI 3-4.5%) for transsphenoidal, 9% (CI 7.2-11.3%) for expanded endonasal, and 5.3% (CI 3.4-7%) for studies describing both. Further meaningful meta-analyses of repair methods were not performed due to significant repair protocol heterogeneity. CONCLUSIONS: Modern reconstructive protocols are heterogeneous and there is limited evidence to suggest the optimal repair technique after pituitary and skull base tumour resection. Further studies are needed to guide practice.

Journal article

COVIDSurg Collaborative, GlobalSurg Collaborative, 2021, SARS‐CoV‐2 infection and venous thromboembolism after surgery: an international prospective cohort study, Anaesthesia, ISSN: 0003-2409

SARS-CoV-2 has been associated with an increased rate of venous thromboembolism in critically ill patients. Since surgical patients are already at higher risk of venous thromboembolism than general populations, this study aimed to determine if patients with peri-operative or prior SARS-CoV-2 were at further increased risk of venous thromboembolism. We conducted a planned sub-study and analysis from an international, multicentre, prospective cohort study of elective and emergency patients undergoing surgery during October 2020. Patients from all surgical specialties were included. The primary outcome measure was venous thromboembolism (pulmonary embolism or deep vein thrombosis) within 30 days of surgery. SARS-CoV-2 diagnosis was defined as peri-operative (7 days before to 30 days after surgery); recent (1–6 weeks before surgery); previous (≥7 weeks before surgery); or none. Information on prophylaxis regimens or pre-operative anti-coagulation for baseline comorbidities was not available. Postoperative venous thromboembolism rate was 0.5% (666/123,591) in patients without SARS-CoV-2; 2.2% (50/2317) in patients with peri-operative SARS-CoV-2; 1.6% (15/953) in patients with recent SARS-CoV-2; and 1.0% (11/1148) in patients with previous SARS-CoV-2. After adjustment for confounding factors, patients with peri-operative (adjusted odds ratio 1.5 (95%CI 1.1–2.0)) and recent SARS-CoV-2 (1.9 (95%CI 1.2–3.3)) remained at higher risk of venous thromboembolism, with a borderline finding in previous SARS-CoV-2 (1.7 (95%CI 0.9–3.0)). Overall, venous thromboembolism was independently associated with 30-day mortality (5.4 (95%CI 4.3–6.7)). In patients with SARS-CoV-2, mortality without venous thromboembolism was 7.4% (319/4342) and with venous thromboembolism was 40.8% (31/76). Patients undergoing surgery with peri-operative or recent SARS-CoV-2 appear to be at increased risk of postoperative venous thromboembolism compared with patients with no his

Journal article

COVIDSurg Collaborative, GlobalSurg Collaborative, Shalhoub J, 2021, Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study, Anaesthesia, ISSN: 0003-2409

Journal article

Cabrilo I, Delaunay R, Heaysman CL, Ourselin S, Vitiello V, Vercauteren T, Marcus HJ, Dorward NLet al., 2021, A Novel Intraoperative Ultrasound Probe for Transsphenoidal Surgery: First-in-human study, SURGICAL INNOVATION, ISSN: 1553-3506

Journal article

Marcus HJ, Khan DZ, Borg A, Buchfelder M, Cetas JS, Collins JW, Dorward NL, Fleseriu M, Gurnell M, Javadpour M, Jones PS, Koh CH, Layard Horsfall H, Mamelak AN, Mortini P, Muirhead W, Oyesiku NM, Schwartz TH, Sinha S, Stoyanov D, Syro LV, Tsermoulas G, Williams A, Winder MJ, Zada G, Laws ERet al., 2021, Pituitary society expert Delphi consensus: operative workflow in endoscopic transsphenoidal pituitary adenoma resection, Pituitary, ISSN: 1386-341X

PurposeSurgical workflow analysis seeks to systematically break down operations into hierarchal components. It facilitates education, training, and understanding of surgical variations. There are known educational demands and variations in surgical practice in endoscopic transsphenoidal approaches to pituitary adenomas. Through an iterative consensus process, we generated a surgical workflow reflective of contemporary surgical practice.MethodsA mixed-methods consensus process composed of a literature review and iterative Delphi surveys was carried out within the Pituitary Society. Each round of the survey was repeated until data saturation and > 90% consensus was reached.ResultsThere was a 100% response rate and no attrition across both Delphi rounds. Eighteen international expert panel members participated. An extensive workflow of 4 phases (nasal, sphenoid, sellar and closure) and 40 steps, with associated technical errors and adverse events, were agreed upon by 100% of panel members across rounds. Both core and case-specific or surgeon-specific variations in operative steps were captured.ConclusionsThrough an international expert panel consensus, a workflow for the performance of endoscopic transsphenoidal pituitary adenoma resection has been generated. This workflow captures a wide range of contemporary operative practice. The agreed “core” steps will serve as a foundation for education, training, assessment and technological development (e.g. models and simulators). The “optional” steps highlight areas of heterogeneity of practice that will benefit from further research (e.g. methods of skull base repair). Further adjustments could be made to increase applicability around the world.

Journal article

Avery KNL, Wilson N, Macefield R, McNair A, Hoffmann C, Blazeby JM, Potter S, Core Outcomes for early pHasE Surgical Innovation and deVicEs COHESIVE study steering group Mr Alberto Casonato, TOKA HEALTHCARE, UK; Mr Thomas A Drake, University of Edinburgh, UK; Dr Camilla Fleetcroft, The Medicines and Healthcare Products Regulatory Agency, UK; Mr Matthew Gardiner, Kennedy Institute of Rheumatology, UK; Mr Henk Giele, University of Oxford, UK; Dr James Glasbey, University of Birmingham, UK; Mr Robert Hinchliffe, University of Bristol, UK; Ms Allison Hirst, University of Oxford, UK; Mr Stephen Johnston, Johnson & Johnson, USA; Mr Angelos Kolias, University of Cambridge, UK; Ms Vee Mapunde, National Institute for Health Research Surgical MedTech Co-operative, UK; Mr Hani Marcus, National Hospital for Neurology and Neurosurgery, UK; Dr Bethany Shinkins, University of Leeds, UK; Mr Neil Smart, Royal Devon & Exeter Hospital, UK; Dr Amie Smirthwaite, Medical Devices Group, British Standards Institution, UK; Mrs Sarah Squire, Patient representative, UK; Mr Alan Thomas, Patient representative, UK; Dr Emma Thomas-Jones, Cardiff University, UK; Mr Christopher Twine, North Bristol NHS Trust, UK; Dr Cherry-Ann Waldron, Cardiff University, UK; Mr Pete Wheatstone, Patient representative, UK; Professor Paula Williamson, University of Liverpool UKet al., 2021, A core Outcome Set for Seamless, Standardized Evaluation of Innovative Surgical Procedures and Devices (COHESIVE): A Patient and Professional Stakeholder consensus Study., Ann Surg

OBJECTIVE: To develop a core outcome set (COS), an agreed minimum set of outcomes to measure and report in all studies evaluating the introduction and evaluation of novel surgical techniques. SUMMARY BACKGROUND DATA: Agreement on the key outcomes to measure and report for safe and efficient surgical innovation is lacking, hindering transparency and risking patient harm. METHODS: (I) Generation of a list of outcome domains from published innovation-specific literature, policy/regulatory body documents, and surgeon interviews; (II) Prioritization of identified outcome domains using an international, multi-stakeholder Delphi survey; (III) Consensus meeting to agree the final COS. Participants were international stakeholders, including patients/public, surgeons, device manufacturers, regulators, trialists, methodologists and journal editors. RESULTS: 7,972 verbatim outcomes were identified, categorized into 32 domains, and formatted into survey items/questions. 410 international participants (220 professionals, 190 patients/public) completed at least one round 1 survey item, of which 153 (69.5%) professionals and 116 (61.1%) patients completed at least one round 2 item. 12 outcomes were scored 'consensus in' ('very important' by ≥70% of patients and professionals) and 20 'no consensus'. A consensus meeting, involving 19 professionals and 10 patient/public representatives, led to agreement on a final 8-domain COS. Six domains are specific to a surgical innovation context: modifications, unexpected disadvantages, device problems, technical procedure success, whether the overall desired effect was achieved, surgeons'/operators' experience. Two domains relate to intended benefits and expected disadvantages. CONCLUSIONS: The COS is recommended for use in all studies prior to definitive RCT evaluation to promote safe, transparent, and efficient surgical innovation.

Journal article

COVIDSurg Collaborative, GlobalSurg Collaborative, 2021, Timing of surgery following SARS‐CoV‐2 infection: an international prospective cohort study, Anaesthesia, Vol: 76, Pages: 748-758, ISSN: 0003-2409

Peri‐operative SARS‐CoV‐2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS‐CoV‐2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre‐operative SARS‐CoV‐2 infection were compared with those without previous SARS‐CoV‐2 infection. The primary outcome measure was 30‐day postoperative mortality. Logistic regression models were used to calculate adjusted 30‐day mortality rates stratified by time from diagnosis of SARS‐CoV‐2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre‐operative SARS‐CoV‐2 diagnosis. Adjusted 30‐day mortality in patients without SARS‐CoV‐2 infection was 1.5% (95%CI 1.4–1.5). In patients with a pre‐operative SARS‐CoV‐2 diagnosis, mortality was increased in patients having surgery within 0–2 weeks, 3–4 weeks and 5–6 weeks of the diagnosis (odds ratio (95%CI) 4.1% (3.3–4.8), 3.9% (2.6–5.1) and 3.6% (2.0–5.2), respectively). Surgery performed ≥ 7 weeks after SARS‐CoV‐2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5% (0.9–2.1%)). After a ≥ 7 week delay in undertaking surgery following SARS‐CoV‐2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2–8.7) vs. 2.4% (95%CI 1.4–3.4) vs. 1.3% (95%CI 0.6–2.0%), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS‐CoV‐2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.

Journal article

Dimitrakakis E, Lindenroth L, Dwyer G, Aylmore H, Dorward NL, Marcus HJ, Stoyanov Det al., 2021, An intuitive surgical handle design for robotic neurosurgery, International Journal of Computer Assisted Radiology and Surgery, Vol: 16, Pages: 1131-1139, ISSN: 1861-6410

PurposeThe expanded endoscopic endonasal approach, a representative example of keyhole brain surgery, allows access to the pituitary gland and surrounding areas through the nasal and sphenoid cavities. Manipulating rigid instruments through these constrained spaces makes this approach technically challenging, and thus, a handheld robotic instrument could expand the surgeon’s capabilities. In this study, we present an intuitive handle prototype for such a robotic instrument.MethodsWe have designed and fabricated a surgical instrument handle prototype that maps the surgeon’s wrist directly to the robot joints. To alleviate the surgeon’s wrist of any excessive strain and fatigue, the tool is mounted on the surgeon’s forearm, making it parallel with the instrument’s shaft. To evaluate the handle’s performance and limitations, we constructed a surgical task simulator and compared our novel handle with a standard neurosurgical tool, with the tasks being performed by a consultant neurosurgeon.ResultsWhile using the proposed handle, the surgeon’s average success rate was 80%, compared to 41% when using a conventional tool. Additionally, the surgeon’s body posture while using the suggested prototype was deemed acceptable by the Rapid Upper Limb Assessment ergonomic survey, while early results indicate the absence of a learning curve.ConclusionsBased on these preliminary results, the proposed handle prototype could offer an improvement over current neurosurgical tools and procedural ergonomics. By redirecting forces applied during the procedure to the forearm of the surgeon, and allowing for intuitive surgeon wrist to robot-joints movement mapping without compromising the robotic end effector’s expanded workspace, we believe that this handle could prove a substantial step toward improved neurosurgical instrumentation.

Journal article

Davids J, Makariou S-G, Ashrafian H, Darzi A, Marcus HJ, Giannarou Set al., 2021, Automated Vision-Based Microsurgical Skill Analysis in Neurosurgery Using Deep Learning: Development and Preclinical Validation, WORLD NEUROSURGERY, Vol: 149, Pages: E669-E686, ISSN: 1878-8750

Journal article

Bandyopadhyay S, Khan DZ, Marcus HJ, Schroeder BE, Patel V, ODonnell A, Ahmed S, Alalade AF, Ali AMS, Allison C, Al-Barazi S, Al-Mahfoudh R, Amarouche M, Bahl A, Bennett D, Bhalla R, Bhatt P, Boukas A, Cabrilo I, Chadwick A, Chowdhury YA, Choi D, Cudlip SA, Donnelly N, Dorward NL, Dow G, Fountain DM, Grieve J, Giamouriadis A, Gilkes C, Gnanalingham K, Halliday J, Hanna B, Hayhurst C, Hempenstall J, Henderson D, Hossain-Ibrahim K, Hirst T, Hughes M, Javadpour M, Jenkins A, Kamel M, Mannion RJ, Kolias AG, Khan H, Khan MS, Lacy P, Mahmood S, Maratos E, Martin A, Mathad N, McAleavey P, Mendoza N, Millward CP, Mirza S, Muquit S, Murray D, Naik PP, Nair R, Nicholson C, Paluzzi A, Pathmanaban O, Paraskevopoulos D, Pollock J, Phillips N, Piper RJ, Ram B, Robertson I, Roman E, Ross P, Santarius T, Sayal P, Shapey J, Sharma R, Shaw S, Shoakazemi A, Sinha S, Solomou G, Stapleton S, Statham P, Stew B, Shumon S, Soon WC, Thomas N, Tsermoulas G, Tysome JR, Varma A, Weir P, Williams A, Youssef Met al., 2021, CSF rhinorrhea after endonasal intervention to the skull base (CRANIAL) - Part 2: impact of COVID-19, World Neurosurgery, Vol: 149, Pages: 1090-1097, ISSN: 1878-8750

BackgroundDuring the pandemic, there has been a concern about the increased risk of perioperative mortality for patients with COVID-19, and the transmission risk to healthcare workers, particularly during endonasal neurosurgical operations. The Pituitary Society produced recommendations to guide management during this era. We sought to assess contemporary neurosurgical practice and the impact of COVID-19.MethodsA multicentre, prospective, observational cohort study was conducted at twelve tertiary neurosurgical units (UK and Ireland). Data were collected from March 23rd-July 31st, 2020 inclusive. Data points collected were patient demographics, pre-operative COVID-19 testing, intra-operative operative modifications, and 30-day COVID infection rates.Results124 patients were included. 116 patients (n=116/124, 94%) underwent COVID-19 testing pre-operatively (TSA: 97/105, 92%; EEA: 19/19, 100%). One patient (n=1/115, 1%) tested positively for COVID-19 pre-operatively, requiring a delay of operation until the infection was confirmed as resolved. Asides from transient diabetes insipidus; no other complications were reported for this case. All theatre staff wore at least level 2 PPE. Adaptations to surgical techniques included minimising drilling, draping modifications, and using nasal iodine wash. At 30 days postoperatively, there was no evidence of COVID infection (symptoms or on formal testing) in our cohort, and no mortality.ConclusionsPreoperative screening protocols and operative modifications have facilitated endonasal neurosurgery during the COVID-19 pandemic, with Pituitary Society guidelines followed for the majority of these operations. There was no evidence of COVID infection in our cohort, and no mortality, supporting the use of risk mitigation strategies to continue endonasal neurosurgery in subsequent pandemic waves.

Journal article

Khan DZ, Marcus HJ, Horsfall HL, Bandyopadhyay S, Schroeder BE, Patel V, ODonnell A, Ahmed S, Alalade AF, Ali AMS, Allison C, Al-Barazi S, Al-Mahfoudh R, Amarouche M, Bahl A, Bennett D, Bhalla R, Bhatt P, Boukas A, Cabrilo I, Chadwick A, Chowdhury YA, Choi D, Cudlip SA, Donnelly N, Dorward NL, Dow G, Fountain DM, Grieve J, Giamouriadis A, Gilkes C, Gnanalingham K, Halliday J, Hanna B, Hayhurst C, Hempenstall J, Henderson D, Hossain-Ibrahim K, Hirst T, Hughes M, Javadpour M, Jenkins A, Kamel M, Mannion RJ, Kolias AG, Khan H, Khan MS, Lacy P, Mahmood S, Maratos E, Martin A, Mathad N, McAleavey P, Mendoza N, Millward CP, Mirza S, Muquit S, Murray D, Naik PP, Nair R, Nicholson C, Paluzzi A, Pathmanaban O, Paraskevopoulos D, Pollock J, Rory J Piper NP, Ram B, Robertson I, Roman E, Ross P, Santarius T, Sayal P, Shapey J, Sharma R, Shaw S, Shoakazemi A, Sinha S, Solomou G, Stapleton S, Statham P, Stew B, Shumon S, Soon WC, Thomas N, Tsermoulas G, Tysome JR, Varma A, Weir P, Williams A, Youssef Met al., 2021, CSF rhinorrhoea after endonasal intervention to the skull base (CRANIAL) - Part 1: multicentre pilot study, World Neurosurgery, Vol: 149, Pages: 1077-1089, ISSN: 1878-8750

BackgroundCRANIAL (CSF Rhinorrhoea After Endonasal Intervention to the Skull Base) is a prospective, multicentre observational study seeking to determine: (1) the scope of skull base repair methods used; and (2) corresponding rates of postoperative CSF rhinorrhoea in endonasal transsphenoidal (TSA) expanded endonasal approaches (EEA) for skull base tumours. We sought to pilot the project - assessing the feasibility and acceptability by gathering preliminary data.MethodsA prospective, observational cohort pilot study was carried out at twelve tertiary UK neurosurgical units. Feedback regarding project positives and challenges were qualitatively analysed.Results187 cases were included, 159 TSA (85%) and 28 EEA (15%). The most common pathologies included: pituitary adenomas (n=141/187), craniopharyngiomas (n=13/187) and skull-base meningiomas (n=4/187). The most common skull base repair techniques used were tissue glues (n=132/187, most commonly Tisseel®), grafts (n=94/187, most commonly fat autograft or Spongostan™) and vascularised flaps (n=51/187, most commonly nasoseptal). These repairs were most frequently supported by nasal packs (n=125/187) and lumbar drains (n=22/187). Biochemically-confirmed CSF rhinorrhoea occurred in 6/159 (3.8%) TSA and 2/28 (7.1%) EEA. Four TSA (3%) and two EEA (7%) cases required operative management for CSF rhinorrhoea (CSF diversion or direct repair). Qualitative feedback was largely positive (themes included: user-friendly and efficient data collection, strong support from senior team members) demonstrating acceptability.ConclusionsOur pilot experience highlights the acceptability and feasibility of CRANIAL. There is a precedent for multicentre dissemination of this project, in order to establish a benchmark of contemporary skull base neurosurgery practice, particularly with respect to EEA cases.KeywordsCerebrospinal fluid rhinorrhoeaCSFCerebrospinal fluid leakskull base surgeryendoscopic endonasalEEA

Journal article

Brennan PM, Borchert R, Coulter C, Critchley GR, Hall B, Holliman D, Phang I, Jefferies SJ, Keni S, Lee L, Liaquat I, Marcus HJ, Thomson S, Thorne L, Vintu M, Wiggins AN, Jenkinson MD, Erridge Set al., 2021, Second surgery for progressive glioblastoma: a multi-centre questionnaire and cohort-based review of clinical decision-making and patient outcomes in current practice, Journal of Neuro-Oncology, Vol: 153, Pages: 99-107, ISSN: 0167-594X

PURPOSE: Glioblastoma prognosis is poor. Treatment options are limited at progression. Surgery may benefit, but no quality guidelines exist to inform patient selection. We sought to describe variations in surgical management at progression, highlight where further evidence is needed, and build towards a consensus strategy. METHODS: Current practice in selection of patients with progressive GBM for second surgery was surveyed online amongst specialists in the UK and Europe. We complemented this with an assessment of practice in a retrospective cohort study from six United Kingdom neurosurgical units. We used descriptive statistics to analyse the data. RESULTS: 234 questionnaire responses were received. Maintaining or improving patient quality of life was key to decision making, with variation as to whether patient age, performance status or intended extent of resection was relevant. MGMT methylation status was not important. Half considered no minimum time after first surgery. 288 patients were reported in the cohort analysis. Median time to second surgery from first surgery 390 days. Median overall survival 815 days, with no association between time to second surgery and time to death (p = 0.874). CONCLUSIONS: This is the most wide-ranging examination of contemporaneous practice in management of GBM progression. Without evidence-based guidelines, the variation is unsurprising. We propose consensus guidelines for consideration, to reduce heterogeneity in decision making, support data collection and analysis of factors influencing outcomes, and to inform clinical trials to establish whether second surgery improves patient outcomes, or simply selects to patients already performing well.

Journal article

Golahmadi AK, Khan DZ, Mylonas GP, Marcus HJet al., 2021, Tool-tissue forces in surgery: A systematic review, Annals of Medicine and Surgery, Vol: 65, Pages: 1-7, ISSN: 2049-0801

BackgroundExcessive tool-tissue interaction forces often result in tissue damage and intraoperative complications, while insufficient forces prevent the completion of the task. This review sought to explore the tool-tissue interaction forces exerted by instruments during surgery across different specialities, tissues, manoeuvres and experience levels.Materials & methodsA PRISMA-guided systematic review was carried out using Embase, Medline and Web of Science databases.ResultsOf 462 articles screened, 45 studies discussing surgical tool-tissue forces were included. The studies were categorized into 9 different specialities with the mean of average forces lowest for ophthalmology (0.04N) and highest for orthopaedic surgery (210N). Nervous tissue required the least amount of force to manipulate (mean of average: 0.4N), whilst connective tissue (including bone) required the most (mean of average: 45.8). For manoeuvres, drilling recorded the highest forces (mean of average: 14N), whilst sharp dissection recorded the lowest (mean of average: 0.03N). When comparing differences in the mean of average forces between groups, novices exerted 22.7% more force than experts, and presence of a feedback mechanism (e.g. audio) reduced exerted forces by 47.9%.ConclusionsThe measurement of tool-tissue forces is a novel but rapidly expanding field. The range of forces applied varies according to surgical speciality, tissue, manoeuvre, operator experience and feedback provided. Knowledge of the safe range of surgical forces will improve surgical safety whilst maintaining effectiveness. Measuring forces during surgery may provide an objective metric for training and assessment. Development of smart instruments, robotics and integrated feedback systems will facilitate this.

Journal article

Marcus HJ, Bennett A, Chari A, Day T, Hirst A, Hughes-Hallett A, Kolias A, Kwasnicki RM, Martin J, Rovers M, Squire SE, McCulloch Pet al., 2021, IDEAL-D Framework for Device Innovation: A Consensus Statement on the Preclinical Stage., Ann Surg

OBJECTIVE: To extend the IDEAL Framework for device innovation, IDEAL-D, to include the preclinical stage of development (Stage 0). BACKGROUND: In previous work, the IDEAL collaboration has proposed frameworks for new surgical techniques and complex therapeutic technologies, the central tenet being that development and evaluation can and should proceed together in an ordered and logical manner that balances innovation and safety. METHODS: Following agreement at the IDEAL Collaboration Council, a multidisciplinary working group was formed comprising 12 representatives from healthcare, academia, industry, and a patient advocate. The group conducted a series of discussions following the principles used in the development of the original IDEAL Framework. Importantly, IDEAL aims for maximal transparency, optimal validity in the evaluation of primary effects and minimisation of potential risk to patients or others. The proposals were subjected to further review and editing by members of the IDEAL Council before a final consensus version was adopted. RESULTS: In considering which studies are required before a first-in-human study, we have: (1) classified devices according to what they do and the risks they carry, (2) classified studies according to what they show about the device, and (3) made recommendations based on the principle that the more invasive and high risk a device is, the greater proof required of their safety and effectiveness prior to progression to clinical studies (Stage 1). CONCLUSIONS: The proposed recommendations for preclinical evaluation of medical devices represent a proportionate and pragmatic approach that balances the de-risking of first-in-human translational studies against the benefits of rapid translation of new devices into clinical practice.

Journal article

Piper RJ, Afshari FT, Soon WC, Kolias AG, Dyson EW, Watkins L, Laing R, Lo WB, Jayamohan Jet al., 2021, UK Chiari 1 Study: protocol for a prospective, observational, multicentre study, BMJ Open, Vol: 11, Pages: e043712-e043712, ISSN: 2044-6055

Introduction Chiari 1 malformation (CM1) is a structural abnormality of the hindbrain characterised by the descent of the cerebellar tonsils through the foramen magnum. The management of patients with CM1 remains contentious since there are currently no UK or international guidelines for clinicians. We therefore propose a collaborative, prospective, multicentre study on the investigation, management and outcome of CM1 in the UK: the UK Chiari 1 Study (UKC1S). Our primary objective is to determine the health-related quality of life (HRQoL) in patients with a new diagnosis of CM1 managed either conservatively or surgically at 12 months of follow-up. We also aim to: (A) determine HRQoL 12 months following surgery; (B) measure complications 12 months following surgery; (C) determine the natural history of patients with CM1 treated conservatively without surgery; (D) determine the radiological correlates of presenting symptoms, signs and outcomes; and (E) determine the scope and variation within UK practice in referral patterns, patient pathways, investigations and surgical decisions.Methods and analysis The UKC1S will be a prospective, multicentre and observational study that will follow the British Neurosurgical Trainee Research Collaborative model of collaborative research. Patients will be recruited after attending their first neurosurgical outpatient clinic appointment. Follow-up data will be collected from all patients at 12 months from baseline regardless of whether they are treated surgically or not. A further 12-month postoperative follow-up timepoint will be added for patients treated with decompressive surgery. The study is expected to last three years.Ethics and dissemination The UKC1S received a favourable ethical opinion from the East Midlands Leicester South Research Ethics Committee (REC reference: 20/EM/0053; IRAS 269739) and the Health Research Authority. The results of the study will be published in peer-reviewed medical journals, presented at scientif

Journal article

Collins JW, Marcus HJ, Ghazi A, Sridhar A, Hashimoto D, Hager G, Arezzo A, Jannin P, Maier-Hein L, Marz K, Valdastri P, Mori K, Elson D, Giannarou S, Slack M, Hares L, Beaulieu Y, Levy J, Laplante G, Ramadorai A, Jarc A, Andrews B, Garcia P, Neemuchwala H, Andrusaite A, Kimpe T, Hawkes D, Kelly JD, Stoyanov Det al., 2021, Ethical implications of AI in robotic surgical training: A Delphi consensus statement, European Urology Focus, ISSN: 2405-4569

ContextAs the role of AI in healthcare continues to expand there is increasing awareness of the potential pitfalls of AI and the need for guidance to avoid them.ObjectivesTo provide ethical guidance on developing narrow AI applications for surgical training curricula. We define standardised approaches to developing AI driven applications in surgical training that address current recognised ethical implications of utilising AI on surgical data. We aim to describe an ethical approach based on the current evidence, understanding of AI and available technologies, by seeking consensus from an expert committee.Evidence acquisitionThe project was carried out in 3 phases: (1) A steering group was formed to review the literature and summarize current evidence. (2) A larger expert panel convened and discussed the ethical implications of AI application based on the current evidence. A survey was created, with input from panel members. (3) Thirdly, panel-based consensus findings were determined using an online Delphi process to formulate guidance. 30 experts in AI implementation and/or training including clinicians, academics and industry contributed. The Delphi process underwent 3 rounds. Additions to the second and third-round surveys were formulated based on the answers and comments from previous rounds. Consensus opinion was defined as ≥ 80% agreement.Evidence synthesisThere was 100% response from all 3 rounds. The resulting formulated guidance showed good internal consistency, with a Cronbach alpha of >0.8. There was 100% consensus that there is currently a lack of guidance on the utilisation of AI in the setting of robotic surgical training. Consensus was reached in multiple areas, including: 1. Data protection and privacy; 2. Reproducibility and transparency; 3. Predictive analytics; 4. Inherent biases; 5. Areas of training most likely to benefit from AI.ConclusionsUsing the Delphi methodology, we achieved international consensus among experts to develop and reach

Journal article

Douglas DR, Choi D, Marcus HJ, Muirhead W, Reddy U, Stewart T, Luoma AMVet al., 2021, Wellbeing of Frontline Health Care Workers After the First SARS-CoV-2 Pandemic Surge at a Neuroscience Centre: A Cross-sectional Survey., J Neurosurg Anesthesiol

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has affected people of all ages, races, and socioeconomic groups, and placed extraordinary stress on health care workers (HCWs). We measured the prevalence of burnout and assessed wellbeing and quality of life (QoL) in HCWs at a single UK neuroscience center after the first pandemic surge. METHODS: A 38-item electronic questionnaire was disseminated through local team email lists between May 22 and June 7, 2020, to HCWs in a university neurosciences center. Burnout was measured using the single-item Emotional Exhaustion and Depersonalization scales, and wellbeing and QoL assessed using the Linear Analogue Self-Assessment Scale and the EuroQol-5 Dimension instrument. RESULTS: The response rate was 57.4% (n=234); 58.2% of respondents were nurses, 69.4% were women and 40.1% were aged 25 to 34 years. Overall, 21.4% of respondents reported burnout assessed by the Emotional Exhaustion scale; burnout was higher for nurses (23.5%) and allied health care professionals (22.5%) compared with doctors (16.4%). HCWs from ethnic minority groups reported a higher rate of burnout (24.5%) compared with white HCWs (15.0%). There were no differences in reported wellbeing or QoL between professional groups, or HCW age, sex, or race. Nurses (36.8%) and staff from ethnic minority groups (34.6%) were more fearful for their health than others. CONCLUSIONS: Our findings highlight the prevalence of HCW burnout after the first surge of the pandemic, with an increased risk of burnout among nurses and staff from ethnic minority groups. Both nursing and staff from ethnic minority groups were also more fearful for their health. With ongoing pandemic surges, the impact on HCW wellbeing should be continuously assessed to ensure that local strategies to support staff wellbeing are diverse and inclusive.

Journal article

COVIDSurg Collaborative, GlobalSurg Collaborative, 2021, SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study., British Journal of Surgery, ISSN: 0007-1323

Journal article

Zamanipoor Najafabadi AH, Khan DZ, Muskens IS, Broekman MLD, Dorward NL, van Furth WR, Marcus HJet al., 2021, Trends in cerebrospinal fluid leak rates following the extended endoscopic endonasal approach for anterior skull base meningioma: a meta-analysis over the last 20 years, Acta Neurochirurgica: the European journal of neurosurgery, Vol: 163, Pages: 711-719, ISSN: 0001-6268

OBJECTIVE: The extended endoscopic approach provides unimpaired visualization and direct access to ventral skull base pathology, but is associated with cerebrospinal fluid (CSF) leak in up to 25% of patients. To evaluate the impact of improved surgical techniques and devices to better repair skull base defects, we assessed published surgical outcomes of the extended endoscopic endonasal approach in the last two decades for a well-defined homogenous group of tuberculum sellae and olfactory groove meningioma patients. METHODS: Random-effects meta-analyses were performed for studies published between 2004 (first publications) and April 2020. We evaluated CSF leak as primary outcome. Secondary outcomes were gross total resection, improvement in visual outcomes in those presenting with a deficit, intraoperative arterial injury, and 30-day mortality. For the main analyses, publications were pragmatically grouped based on publication year in three categories: 2004-2010, 2011-2015, and 2016-2020. RESULTS: We included 29 studies describing 540 patients with tuberculum sellae and 115 with olfactory groove meningioma. The percentage patients with CSF leak dropped over time from 22% (95% CI: 6-43%) in studies published between 2004 and 2010, to 16% (95% CI: 11-23%) between 2011 and 2015, and 4% (95% CI: 1-9%) between 2016 and 2020. Outcomes of gross total resection, visual improvement, intraoperative arterial injury, and 30-day mortality remained stable over time CONCLUSIONS: We report a noticeable decrease in CSF leak over time, which might be attributed to the development and improvement of new closure techniques (e.g., Hadad-Bassagasteguy flap, and gasket seal), refined multilayer repair protocols, and lumbar drain usage.

Journal article

Tukra S, Marcus HJ, Giannarou S, 2021, See-Through Vision with Unsupervised Scene Occlusion Reconstruction., IEEE Trans Pattern Anal Mach Intell, Vol: PP

Among the greatest of the challenges of Minimally Invasive Surgery (MIS) is the inadequate visualisation of the surgical field through keyhole incisions. Moreover, occlusions caused by instruments or bleeding can completely obfuscate anatomical landmarks, reduce surgical vision and lead to iatrogenic injury. The aim of this paper is to propose an unsupervised end-to-end deep learning framework, based on Fully Convolutional Neural networks to reconstruct the view of the surgical scene under occlusions and provide the surgeon with intraoperative see-through vision in these areas. A novel generative densely connected encoder-decoder architecture has been designed which enables the incorporation of temporal information by introducing a new type of 3D convolution, the so called 3D partial convolution, to enhance the learning capabilities of the network and fuse temporal and spatial information. To train the proposed framework, a unique loss function has been proposed which combines perceptual, reconstruction, style, temporal and adversarial loss terms, for generating high fidelity image reconstructions. Advancing the state-of-the-art, our method can reconstruct the underlying view obstructed by irregularly shaped occlusions of divergent size, location and orientation. The proposed method has been validated on in-vivo MIS video data, as well as natural scenes on a range of occlusion-to-image (OIR) ratios.

Journal article

Horsfall HL, Palmisciano P, Khan DZ, Muirhead W, Koh CH, Stoyanov D, Marcus HJet al., 2021, Attitudes of the surgical team toward artificial intelligence in neurosurgery: an international two-stage cross-sectional survey., World Neurosurgery, Vol: 146, Pages: e724-e730, ISSN: 1878-8750

BACKGROUND: Artificial Intelligence (AI) has the potential to disrupt how we diagnose and treat patients. Previous work by our group has demonstrated that the majority of patients and their relatives feel comfortable with the application of AI to augment surgical care. The aim of this study was to similarly evaluate the attitudes of surgeons and the wider surgical team towards the role of AI in neurosurgery. METHODS: In a two-stage cross sectional survey, an initial open-question qualitative survey was created to determine the perspective of the surgical team on AI in neurosurgery, including surgeons, anaesthetists, nurses, and theatre practitioners. Thematic analysis was performed to develop a second stage quantitative survey that was distributed via social media. We assessed the extent to which they agreed and were comfortable with real-world AI implementation using a 5-point Likert scale. RESULTS: In the first stage survey, 33 participants responded. Six main themes were identified: imaging interpretation and pre-operative diagnosis; co-ordination of the surgical team; operative planning; real-time alert of hazards and complications; autonomous surgery; post-operative management and follow-up. In the second stage, 100 participants responded. Responders somewhat agreed or strongly agreed about AI utilised for imaging interpretation (62%), operative planning (82%), co-ordination of the surgical team (70%), real-time alert of hazards and complications (85%), and autonomous surgery (66%). The role of AI within post-operative management and follow-up was less agreeable (49%). CONCLUSION: This survey highlights that the majority of surgeons and the wider surgical team both agree and are comfortable with the application of AI within neurosurgery.

Journal article

Chari A, Budhdeo S, Sparks R, Barone DG, Marcus HJ, Pereira EAC, Tisdall MMet al., 2021, Brain-Machine Interfaces: The Role of the Neurosurgeon, WORLD NEUROSURGERY, Vol: 146, Pages: 140-147, ISSN: 1878-8750

Journal article

Hussein Z, Glynn N, Martin N, Alkrekshi A, Mendoza N, Nair R, McCullough K, Marcus HJ, Dorward N, Grieve J, Fersht N, Dyson E, Bouloux P-M, Druce M, Baldeweg SEet al., 2021, Temporal trends in craniopharyngioma management and long-term endocrine outcomes: a multicentre cross-sectional study., Clinical Endocrinology, Vol: 94, Pages: 242-249, ISSN: 0300-0664

BACKGROUND: The optimal management of craniopharyngiomas remains controversial. OBJECTIVES: To examine temporal trends in the management of craniopharyngioma with a focus on endocrine outcomes. METHODS: This was a cross-sectional, multicentre study. Patients treated between 1951 and 2015 were identified and divided into four quartiles. Demographics, presentation, treatment and outcomes were collected. RESULTS: In total, 142 patients with childhood onset craniopharyngioma (48/142; 34%) and adult onset disease (94/142; 66%) were included. The median follow-up was 15 years (IQR 5 - 23 years). Across quartiles, there was a significant trend towards using transsphenoidal surgery (p <0.0001). The overall use of radiotherapy was not different among the four quartiles (p = 0.33). At the latest clinical review, the incidence of GH, ACTH, gonadotrophins deficiencies as well as anterior panhypopituitarism fell significantly across the duration of the study. Anterior panhypopituitarism was not affected by treatment modality (surgery vs surgery and radiotherapy) (p = 0.23). There was no difference in the incidence of high BMI (≥ 25 kg/m2 ) among the four quartiles (p = 0.14). BMI was higher in patients who treated with surgery and radiotherapy than those treated with surgery only (p = 0.006). Tumour regrowth occurred in 51 patients (51/142; 36%) with no difference in regrowth among quartiles over the time course of the study (p = 0.15). CONCLUSION: We demonstrate a significant reduction in panhypopituitarism in craniopharyngioma patients over time, most likely because of a trend towards more transsphenoidal surgery. However, long term endocrine sequelae remain common and lifelong follow-up is required.

Journal article

Payne CJ, Dwyer G, Dimitrakakis E, Marcus HJet al., 2021, Basic concepts in robotics, Neuromethods, Pages: 3-34

This chapter aims to provide a practical introduction to the basic concepts in robotics relevant to neurosurgical robotic systems. We start by introducing different robotic architectures and discussing how these contrasting fundamental approaches are suited to different neurosurgical applications. We then examine the different actuators and mechanisms that give robots motion. Next, we look at the different sensing technologies that allow robots to sense themselves and their external environment. With some knowledge of robot architectures, actuation, and sensing, we then examine how these elements can be combined together into a controllable robotic system. Finally, we introduce the different user-interface paradigms applicable to neurosurgical robots.

Book chapter

Payne CJ, Vyas K, Bautista-Salinas D, Zhang D, Marcus HJ, Yang GZet al., 2021, Shared-control robots, Neuromethods, Pages: 63-79

This chapter reviews shared-control robots, a class of robotic device in which the surgeon and the robot simultaneously manipulate the surgical tool together. The shared-control approach seeks to exploit the superior aspects of humans and machines, to enable more precise interventions while ensuring the human surgeon retains executive control. Much of the technology discussed in this chapter is emerging research and many of the described systems have been developed for generic microsurgical interventions. Nonetheless, the broad concepts behind these surgical systems are highly applicable to neurosurgery and particularly to microsurgical procedures. We start by presenting an exemplar of a grounded, shared-control robot: the Steady-Hand system. We then review a series of handheld smart surgical devices, including Micron, a handheld tremor cancellation device. This chapter also presents handheld devices capable of augmenting haptic feedback to surgeons performing delicate neurosurgical tasks, image-guided handheld devices with embedded robotic actuation, and a new generation of handheld microscopic imaging devices for visualizing tumors.

Book chapter

Glasbey JC, Omar O, Nepogodiev D, Minaya-Bravo A, Bankhead-Kendall BK, Fiore M, Futaba K, Gabre-Kidan A, Gujjuri RR, Isik A, Kaafarani HMA, Kamarajah SK, Li E, Loeffler MW, McLean KA, Outani O, Ntirenganya F, Satoi S, Shaw R, Simoes JFF, Stewart GD, Tabiri S, Trout IM, Bhangu AA, Glasbey JC, Omar O, Bhangu AA, Siaw-Acheampong K, Benson RA, Bywater E, Chaudhry D, Dawson BE, Evans JP, Glasbey JC, Gujjuri RR, Heritage E, Jones CS, Kamarajah SK, Khatri C, Khaw RA, Keatley JM, Knight A, Lawday S, Li E, Mann HS, Marson EJ, McLean KA, Mckay SC, Mills EC, Nepogodiev D, Pellino G, Picciochi M, Taylor EH, Tiwari A, Simoes JFF, Trout IM, Venn ML, Wilkin RJW, Bhangu A, Glasbey JC, Smart NJ, Minaya-Bravo A, Evans JP, Gallo G, Moug S, Pata F, Pockney P, Di Saverio S, Vallance A, Vimalchandran D, Griffiths EA, Kamarajah SK, Evans RPT, Townend P, Roberts K, McKay S, Isaac J, Satoi S, Edwards J, Coonar AS, Marchbank A, Caruana EJ, Layton GR, Patel A, Brunelli A, Ford S, Desai A, Gronchi A, Fiore M, Almond M, Tirotta F, Dumitra S, Kolias A, Price SJ, Fountain DM, Jenkinson MD, Hutchinson P, Marcus HJ, Piper RJ, Lippa L, Servadei F, Esene I, Freyschlag C, Neville I, Rosseau G, Schaller K, Demetriades AK, Robertson F, Alamri A, Shaw R, Schache AG, Winter SC, Ho M, Nankivell P, Biel JR, Batstone M, Ganly I, Vidya R, Wilkins A, Singh JK, Thekinkattil D, Sundar S, Fotopoulou C, Leung E, Khan T, Chiva L, Sehouli J, Fagotti A, Cohen P, Gutelkin M, Ghebre R, Konney T, Pareja R, Bristow R, Dowdy S, Rajkumar STS, Ng J, Fujiwara K, Stewart GD, Lamb B, Narahari K, McNeill A, Colquhoun A, McGrath J, Bromage S, Barod R, Kasivisvanathan V, Klatte T, Simoes JFF, Abbott TEF, Abukhalaf S, Adamina M, Ademuyiwa AO, Agarwal A, Akkulak M, Alameer E, Alderson D, Alakaloko F, Albertsmeiers M, Alser O, Alshaar M, Alshryda S, Arnaud AP, Augestad KM, Ayasra F, Azevedo J, Bankhead-Kendall BK, Barlow E, Beard D, Benson RA, Blanco-Colino R, Brar A, Minaya-Bravo A, Breen KA, Bretherton C, Buarque IL, Burke J, Caruet al., 2021, Preoperative nasopharyngeal swab testing and postoperative pulmonary complications in patients undergoing elective surgery during the SARS-CoV-2 pandemic, BRITISH JOURNAL OF SURGERY, Vol: 108, Pages: 88-96, ISSN: 0007-1323

Journal article

Marcus HJ, Payne CJ, 2021, Translation, Neuromethods, Pages: 81-91

Translation is the process by which medical innovations, such as neurosurgical robots, are brought from the laboratory into the operating room. This process has been described as a continuum punctuated by several well-defined chasms: first, the development of a robot culminating in a first-in-human study; second, the evaluation of a robot resulting in regulatory clearance or approval; and third, the adoption of a robot by neurosurgeons. In this chapter we discuss the process of innovation, and the stages of translation, the central tenet being that development and evaluation can and should proceed together in an ordered and logical manner. We also provide some practical advice on how innovators can optimize their likelihood of success.

Book chapter

Hutchinson PJ, Edlmann E, Bulters D, Zolnourian A, Holton P, Suttner N, Agyemang K, Thomson S, Anderson IA, Al-Tamimi YZ, Henderson D, Whitfield PC, Gherle M, Brennan PM, Allison A, Thelin EP, Tarantino S, Pantaleo B, Caldwell K, Davis-Wilkie C, Mee H, Warburton EA, Barton G, Chari A, Marcus HJ, King AT, Belli A, Myint PK, Wilkinson I, Santarius T, Turner C, Bond S, Kolias AG, British Neurosurgical Trainee Research Collaborative and Dex-CSDH Trial Collaboratorset al., 2020, Trial of dexamethasone for chronic subdural hematoma., New England Journal of Medicine, Vol: 383, Pages: 2616-2627, ISSN: 0028-4793

BACKGROUND: Chronic subdural hematoma is a common neurologic disorder that is especially prevalent among older people. The effect of dexamethasone on outcomes in patients with chronic subdural hematoma has not been well studied. METHODS: We conducted a multicenter, randomized trial in the United Kingdom that enrolled adult patients with symptomatic chronic subdural hematoma. The patients were assigned in a 1:1 ratio to receive a 2-week tapering course of oral dexamethasone, starting at 8 mg twice daily, or placebo. The decision to surgically evacuate the hematoma was made by the treating clinician. The primary outcome was a score of 0 to 3, representing a favorable outcome, on the modified Rankin scale at 6 months after randomization; scores range from 0 (no symptoms) to 6 (death). RESULTS: From August 2015 through November 2019, a total of 748 patients were included in the trial after randomization - 375 were assigned to the dexamethasone group and 373 to the placebo group. The mean age of the patients was 74 years, and 94% underwent surgery to evacuate their hematomas during the index admission; 60% in both groups had a score of 1 to 3 on the modified Rankin scale at admission. In a modified intention-to-treat analysis that excluded the patients who withdrew consent for participation in the trial or who were lost to follow-up, leaving a total of 680 patients, a favorable outcome was reported in 286 of 341 patients (83.9%) in the dexamethasone group and in 306 of 339 patients (90.3%) in the placebo group (difference, -6.4 percentage points [95% confidence interval, -11.4 to -1.4] in favor of the placebo group; P = 0.01). Among the patients with available data, repeat surgery for recurrence of the hematoma was performed in 6 of 349 patients (1.7%) in the dexamethasone group and in 25 of 350 patients (7.1%) in the placebo group. More adverse events occurred in the dexamethasone group than in the placebo group. CONCLUSIONS: Among adults with symptomatic

Journal article

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