Grading of EVD Placement

  1. Grade I
    • optimal placement in the ipsilateral frontal horn or third ventricle
  2. Grade 2
    • functional placement in the contralateral ventricle or noneloquent (parenchyma)
  3. Grade 3
    • suboptimal placement in the eloquent cortex [(parenchyma) or nontarget CSF space, with or without functional drainage


Kakarla, Udaya K. et al. “Safety and accuracy of bedside external ventricular drain placment”. Operative Neurosurgery 63 (2008): ONS162-ONS167.


Ghajar Guide

The Ghajar guide is a device used to improve the accuracy of external ventricular drain (EVD) insertion.  The EVD catheter is traditionally inserted blindly by the neurosurgeon, based on anatomical landmarks (s.a. Kocher’s point).

The Ghajar device is a tripod that is mounted on the skull surface, which guides the path of entry of the EVD catheter.  The investigators of this device noted fewer passes and better accuracy with the use of this device.  Of note, the Neurocritical Care Society guidelines for EVD mentions the Ghajar guide in passing, but recommends the use of Kocher’s point and a trajectory perpendicular to the skull or targeting the contralateral medial canthus as landmarks during EVD insertion.

This device was invented by Jamshid B. G. Ghajar.  See url below for patent details.





Fried, Herbert I. et al. “The Insertion And Management Of External Ventricular Drains: An Evidence-Based Consensus Statement”. Neurocritical Care 24.1 (2016): 61-81. Web.