Single-use optical tracking navigation for external ventricular drain placement: Preclinical 3D-Printed and cadaveric evaluation with a systematic review

Introduction: External ventricular drain (EVD) placement is common in neurosurgery, yet malposition occurs in up to 38% of cases. While technical adjuncts can improve placement accuracy, simpler and more user-friendly solutions are needed. Our novel single-use optical tracking navigation (OTN) device enables real-time image-guided EVD placement. This proof-of-concept study evaluates the accuracy and usability of this device in both 3D-printed and cadaveric head models. Research question: To evaluate the feasibility and accuracy of a single-use OTN system for EVD placement. Material and methods: Three neurosurgeons each performed three OTN-assisted placements in 3D-printed head models (n = 9). An attending neurosurgeon performed two placements in a cadaveric head (n = 2). The primary endpoint was Kakarla grading. Additional outcomes included fluoroscopy-derived tip-to-target distance, placement duration, and user satisfaction (likelihood to recommend (LTR)). Results: All placements were Kakarla grade 1 (total: 11/11, 100%; 95% CI: 0.72-1.00; 3D-printed: 9/9, 95% CI 0.66 -1.00; cadaveric: 2/2, 95% CI: 0.16 - 1.00). Mean fluoroscopy-derived procedural tip-to-target distance was 13.3 ± 6.4 mm in the 3D-printed models and 22.2 ± 3.2 mm in the cadaveric head. Mean procedure time, including registration and calibration, was 12.1 ± 2.1 min. User satisfaction was positive (mean LTR: 7/10). Discussion and conclusion: The OTN device enables accurate, real-time image-guided EVD placement in both bench and cadaveric models, independent of user experience. Main limitations include the small sample size, ex vivo design, and reliance on 2D fluoroscopy for verification. Larger cadaveric series and clinical trials are needed to confirm accuracy and assess clinical utility.