Placement accuracy of external ventricular drain when comparing freehand insertion to neuronavigation guidance in...

External ventricular drain (EVD) placement is a frequently performed neurosurgical procedure. Inaccuracies in drain positioning and the need for multiple passes using the classic freehand insertion technique is well reported in the literature, especially in the traumatic brain injury (TBI) population. The purpose of this study was to evaluate if electromagnetic neuronavigation guidance for EVD insertion improves placement accuracy and minimizes the number of passes in severe TBI patients.

Navigation was applied prospectively for all new severe TBI patients who required ventricular catheter placement over a period of 1 year, and compared with a retrospective cohort of severe TBI patients who had EVD inserted freehand in the preceding year. The placement accuracy was evaluated using the Kakarla grading system; the number of passes was also compared.

Fifty-four cases were recruited: 35 (64.8%) had their EVD placed using the freehand technique and 19 (35.2%) using navigation guidance. In the navigation group, the placement accuracy was: 94.7% (18/19) grade 1, 5.3% (1/19) grade 2, and none at grade 3. In comparison, freehand placement was associated with misplacement (grades 2 and 3) in 42.9% of the cases (p value = 0.009). The number of passes was significantly lower in the navigation group (mean of 1.16 ± 0.38), compared with the freehand group (mean of 1.63 ± 0.88) (p value = 0.018).

Using the navigation to guide EVD placement was associated with a significantly better accuracy and a lower number of passes in severe TBI patients.