Accuracy of Freehand Versus Navigated External Ventricular Drainage and Comparison of Insertion Trajectories: A Systematic Review and Meta Analysis
In brief
Navigated external ventricular drains succeed in 85% vs 70% freehand
A meta-analysis of 30 studies found that image-guided ventriculostomy achieved an 85% success rate, compared with about 70% for the traditional freehand technique. The highest success (nearly 98%) was linked to a specific entry point 10-20 mm anterior to the coronal suture and 20-30 mm lateral to midline. The authors suggest navigation as the new standard, while freehand remains acceptable when resources are limited.
- Journal
- Clinical anatomy (New York, N.Y.) (Q1)
- Published
- 3 September 2026
- Study design
- Systematic review of cohort studies
- Evidence level
- Level 2, Moderate (CEBM 2a)
- Authors
- Adam Sedlák, Martin Černý, Adam Koza, David Kachlík, David Netuka, Lea Mladá, et al.
- PMID
- 42693668
- DOI
- 10.1002/ca.70215
Why clinicians should know about it
- Picked for Anatomy (paper of the day, 5 September 2026): Freehand vs navigated EVD accuracy, ventricular anatomy
Abstract
The external ventricular drainage is a routine neurosurgical procedure, most often performed by cannulating the frontal horn of the lateral ventricle. Various entry points and insertion trajectory definitions have been proposed; nevertheless, it remains unclear which approach yields the highest success rate. Furthermore, in contemporary clinical practice, generally more efficient navigated ventriculostomies are available. This study aims to compare success rates between freehand and navigated procedures and to compare various trajectory definitions. A search of the Cochrane, Embase, PubMed, and Scopus databases was conducted. Inclusion criteria were: (1) studies presenting an unequivocal definition of entrypoint and insertion trajectory; (2) studies reporting a statistically quantifiable outcome. A total of 30 articles met the inclusion criteria. The pooled success rate was 69.7% and 85.1% for freehand and navigated procedures, respectively (3528 vs. 464 cases, p < 0.001). The highest success rate (97.8%, CI 0.949-1.000) was observed for a trajectory defined by entry 10-20 mm anterior to the coronal suture and 20-30 mm lateral to the midline, with catheter direction toward the ipsilateral tragus in the sagittal plane and the ipsilateral medial canthus in the coronal plane. Navigated external ventricular drainage demonstrates significantly higher success rates compared to the freehand technique. Therefore, navigated ventriculostomy should be regarded as the preferred standard of care. In settings where time or resources are constrained, the freehand approach remains a justifiable alternative. Due to missing direct comparison, no single trajectory definition for nonnavigated insertion could be recommended over others.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.