Abstracts vii238 NEURO-ONCOLOGY • November 2022 QLTI-16. ENHANCED RECOVERY AFTER LASER ABLATION SURGERY: A PRELIMINARY ANALYSIS OF A NOVEL PROGRAM Martin Merenzon 1 , Adam Levy 2 , Tiffany Eatz 2 , Alexis Morell 2 , Dominique Higgins 2 , Nitesh Patel 2 , Michael Kader 2 , Daniel Eichberg 2 , Ashish Shah 2 , Michael Silva 2 , Victor Lu 2 , Evan Luther 2 , Marc Bloom 2 , Ricardo Komotar 2 , and Michael Ivan 2 ; 1 University of Miami Hospital, Miami, FL, USA, 2 University of Miami Hospital, Miami, USA INTRODUCTION: The concept of enhanced recovery after sur- gery (ERAS) due to standardized interventions has been gaining more relevance within neurosurgery. Advances were made both in protocols for spine and cranial surgery. These experiences described many bene- fts such as less psychological stress, reduction in hospitalization days, and lower hospital costs, without increasing the incidence of compli- cations. However, no experience has described to date the applicability of an ERAS program for laser ablation thermal therapy (LITT). OB- JECTIVE: To describe our initial experience with the frst enhanced re- covery program reported for laser ablation for brain tumors. Secondly, to summarize the perioperative clinical outcomes of ERAS applied to LITT. METHODS: We performed a retrospective analysis of all adult patients who underwent LITT for oncological lesions from 2013 to 2021. A multidisciplinary program was created by protocolizing inter- ventions carried out along the path of the patient's hospitalization. Each recommendation was individually assessed for its appropriateness for enhancing recovery and for its validity with a focused literature review process. RESULTS: A total of 184 patients were included, with a mean age of 60.7 ± 13.5 years, 35% males. 167 tumors were located in the supratentorial compartment, and 17 were infratentorial; the mean tumor diameter was 1.84 ± 1.04 cm. Among the pathologies treated 50.0% were metastasis, and 36.9% were glioblastomas. The mean postoperative day discharge was 1.2 ± 0.8 days. The readmission rate due to surgical com- plications within 30 days of surgery was 2.7%. These readmission rates fall into what is expected according to published literature without an ERAS program and longer hospital admissions. One death was recorded in the perioperative period. CONCLUSION: Clinical interventions that could constitute an ERAS program are feasible in laser ablation of brain tumors. This study could be useful as a preliminary framework for the development of future guidelines. QLTI-17. PROPHYLACTIC VANCOMYCIN REDUCES OMMAYA RESERVOIR-ASSOCIATED BACTERIAL MENINGITIS: A 12-MONTH PROSPECTIVE STUDY Mara Trifoi 1 , Krishana Sichinga 2 , Matthew Levit 3 , Dawit Aregawi 2 , Brad Zacharia 3 , Alireza Mansouri 4 , and Michael Glantz 5 ; 1 Penn State College of Medicine, Hershey, PA, USA, 2 Penn State Health, Hershey, PA, USA, 3 Penn State Health, Hershey, USA, 4 Penn State Hershey Medical Center, Hershey, PA, USA, 5 Penn State Health Milton S. Hershey Medical Center, Hershey, PA, USA INTRODUCTION: Intraventricular chemotherapy administered through an Ommaya reservoir (OR) constitutes the mainstay of therapy for adults with leptomeningeal metastases from solid and hematologic malignancies. Unfortunately, OR-associated bacterial meningitis remains a relatively frequent, costly, often morbid, and occasionally fatal com- plication, limiting the beneft of this approach. We investigated the po- tential effcacy, cost savings, and toxicity of intraventricular vancomycin co-administered with intraventricular chemotherapy. METHODS: De- tailed demographic, treatment, and outcome data were collected pro- spectively between 5/1/21 and 4/30/22 for 63 consecutive patients at our institution who underwent OR placement and subsequent intraventricular chemotherapy, co-administered with 10 mg of intraventricular vanco- mycin at each treatment.  Reservoir-associated bacterial meningitis was defned as 2 consecutive positive cultures from the cerebrospinal fuid of the same organism or 1 positive culture in the presence of any other clinical or laboratory evidence of infection, or signs of infection at the surgical site. RESULTS: The infection rate was 0% [95% CI 0-6.75%] among the 63 patients and 0% [0-0.76%] in the 501 consecutive treat- ments administered over the 12-month study period compared to 10.25% [7.39- 14.0%] in 322 patients and 1.71% [1.22-2.39%] in 1932 treat- ments over the preceding 5 years. The absolute risk reduction was 10.3% [3.83 - 14.04], p = 0.0049. The number needed to treat was 10 [7-26]. Cost per vancomycin dose was $10.00 ($5,010 over 12 months). The cost of non-surgical treatment of one OR-associated infection is $88,337.70, which translates into a $618,363.90 savings for the estimated 7 patients over 12 months spared an OR-associated infection. Savings were even fur- ther increased if OR removal and subsequent replacement was required. The only other covariate associated with (increased) infection risk on multivariable analysis was treatment number. No treatment-associated toxicity was observed. CONCLUSION: Prophylactic intraventricular vancomycin eliminated OR-associated infection in patients receiving intraventricular chemotherapy. Dramatic cost savings were achieved without added toxicity. QLTI-18. LIQUID BIOPSY: CLINICALLY INTEGRATED RESEARCH IN THE MODERN PANDEMIC ERA Abhinav Nannapaneni 1 , Amanda Wigand 1 , Kelly Tundo 1 , Tobias Walbert 1 , and James Snyder 1 ; 1 Henry Ford Health, Detroit, MI, USA The COVID-19 pandemic forced a redesign of clinical research to adapt to an ever-changing situation while minimizing patient and provider risks and preserving scientifc discovery. During the initial surge of COVID-19, elective healthcare services and non-critical research operations were halted. These changes inspired dispersed health care operations and streamlined clinical research. The frst wave of COVID-19 hit Detroit, Michigan, in March 2020, consuming Henry Ford Health (HFH), in COVID-19 emergency care. HFH has a clinically integrated liquid biopsy (LB) program where enrolled pa- tients provide an LB sample via venipuncture within 7 days of each MRI, typically in the clinic at the point-of-care. Prior to COVID-19, 183 neuro- oncology patients were actively providing LB samples in clinic with a mean of 29.9 specimens monthly. Institutional COVID-19 restrictions on non- critical interactions resulted in months were nearly all outpatient encoun- ters utilized telemedicine and decentralized testing off-site from research operations. This halted LB procurement to 4.55 specimens monthly during early pandemic months. To reduce patient-provider exposure, LB specimens were then procured with the venipuncture for MRI which streamlined LB operations and improved the patient experience. After this change, LB spe- cimen procurement returned to near pre-pandemic levels with a mean of 28.1 monthly specimens, despite a signifcant population utilizing video visits and imaging at satellite or non-HFH centers. The pandemic forced adaptations to patient encounters that have changed how healthcare is de- livered, resulting in parallel changes in research that must be considered in the design of future studies. QLTI-19. EVALUATION OF INTRA-OPERATIVE BRAIN TUMOUR DIAGNOSTIC SERVICES – A LARGE TERTIARY UK CENTRE EXPERIENCE Richard Digby 1 , Piravin Ramakrishnan 2 , Saad Moughal 2 , Arundhati Chakrabarty 1 , and Ryan Mathew 2 ; 1 Department of Histopathology, Leeds Teaching Hospitals NHS Trust, Leeds, England, United Kingdom, 2 Department of Neurosurgery, Leeds Teaching Hospitals NHS Trust, Leeds, England, United Kingdom INTRODUCTION: Brain tumour intraoperative diagnosis (smear cytology, frozen section) is a commonly performed, routine diagnostic service. Cur- rently, samples must be transported from the operating room (OR) to path- ology, impacting turnaround time (TAT), carbon emissions (if cross-site), and motivation for repeat sampling. We performed a broad evaluation of current practice in a large, tertiary, UK brain tumour centre, to identify potential gains in real-time tissue diagnosis. METHODS: All brain tumour samples (n=228) sent for intraoperative diagnosis in 2021 were analysed retrospectively. TAT was assessed by capturing different timepoints along the pathway. Concordance be- tween diagnoses at the following stages was determined: preoperatively based on radiology, intraoperatively (frozen section or smear), provisional paraffn and fnal integrated. Additionally, we anonymously surveyed neurosurgeons’ opinions (n=18) on the current service. RESULTS: The mean (±SD) specimen transportation time was 10.6±2.0 minutes, with an estimated total TAT of 30-60 minutes. Intraoperative diagnosis provided a slightly higher rate of con- cordance with provisional paraffn diagnosis than preoperative radiological diagnosis (89.5% vs 86.3%). Non-concordance was most commonly due to non-representative sampling (e.g., predominantly necrotic), with no repeat sample being sent/available intraoperatively. Prevailing neurosurgical opinion of the intraoperative diagnostic service was dissatisfaction or neutrality (50% and 39% of respondents), with a minority being positive (11%). Reasons for this included: intraoperative delay due to TAT (47%), perceived inaccuracy of results (41%), and perceived reduced out-of-hours availability (56%). CON- CLUSIONS: Current brain tumour intraoperative diagnostic practice relies on physical sample transportation and manual processing; the resultant long TAT causes surgeon dissatisfaction and dissuades repeat analysis in the case of non-representative sampling. Real-time tissue diagnostic technologies such as OR-sited probe-based confocal endomicroscopy, scanners and Raman spectros- copy should be considered to facilitate faster and repeated examination. The latter may have additional benefts in real-time expert pathology feedback, tu- mour margin-zone analysis and increased extent of resection. QLTI-20. DIGITAL SOLUTIONS TO IMPROVE DATA QUALITY IN NEUROONCOLOGY RESEARCH Amit Ray 1 , Arka Sanka 2 , Kiran Prathapa 2 , Vijay Sreegiriraju 2 , KVRN Kiran Kumar 3 , Yadagiri Balagoni 3 , Samyuktha Sunkara 3 , Ravi Teja Sunkara 3 , Sharath Chandra Nandoori 3 , Sarath Vuyyuru 2 , Pankaj Mishra 3 , and Surya Prakash Madiraju 3 ; 1 Apollo Hospitals, Hyderabad, India, 2 Exsegen Genomics Research Pvt. Ltd., Hyderabad, India, 3 Exsegen Genomics Pvt. Ltd., Hyderabad, India PROBLEM: Data quality impacts the validity of results obtained through clinical research due to several reasons. These include degradation of tumor Downloaded from https://academic.oup.com/neuro-oncology/article/24/Supplement_7/vii238/6826798 by guest on 30 March 2023