871 Bedside Neuronavigation for External Ventriculostomy as a Training Tool for Success: A Single-institution Experience and Meta-Analysis of Patients Outcomes and Procedural Accuracy

INTRODUCTION: External ventricular drain (EVD) placement is the most universally performed neurosurgical procedure, frequently by trainees. Freehand insertion, which approximates anatomical landmarks to achieve percutaneous ventricular access, bodes a complication risk as high as 40%. Neuronavigation is widely used for neurosurgical procedures; however, its use case for EVD has been inadequately explored. METHODS: A single-institution retrospective cohort study was performed, including all EVDs inserted in 2022. A PRISMA-guided systematic review was then conducted, querying databases for relevant articles. Primary outcomes of interest were optimal positioning (using Kakarla grading) and number of passes for ventricular access. Secondary outcomes included postoperative ventricular enlargement, hemorrhage, edema, and drain malfunction. Clinical data was pooled between single-institution and systematic review for meta-analyses. Outcomes were compared using risk ratios (RR [95% CI]) and standardized mean differences (SMD). RESULTS: Forty-seven patients (49 EVDs) were included from a single institution (17 neuronavigation; 32 freehand). Through systematic review, 1,289 patients (255 neuronavigation; 1,034 freehand) were identified from 10 eligible studies. Pooled together, patients were predominantly male (52%) and adult-aged (90%). EVD indications most commonly included hemorrhage (61%), obstructive pathology (15%), trauma (10%), and infection (7%). 85% of EVDs were placed by neurosurgical trainees. Frequency of catheter malposition was significantly lower in the neuronavigation cohort compared to the freehand cohort (10% vs. 36%; RR, 0.41 [0.24-0.69]). However, number of catheter passes remained the same between cohorts (mean [SD]; 1.11 [0.42] vs. 1.16 [0.51]; SMD; 0.04 [0.48]). Moreover, frequencies of postoperative ventricular enlargement, hemorrhage, edema, and drain malfunction, although were higher in the freehand cohort, did not differ significantly. CONCLUSIONS: These findings suggest neuronavigation helps trainees achieve safe and accurate ventricular access. Neuronavigation-guided external ventriculostomy may offer a promising, accessible, and bedside-ready approach to minimize morbidity, while mastering the procedural technique.