High accuracy of external ventricular drainage placement using anatomical landmarks

Area of Science:

• Neurosurgery
• Medical Imaging

Background:

• The freehand method is conventional for external ventricular drainage (EVD) placement, but its safety as a standard technique is debated.
• Technical aids exist but are not widely adopted due to cost and complexity.
• Previous studies focused on final catheter position, with variable malpositioning rates, but rarely assessed adherence to cranial surface anatomy during insertion.

Purpose of the Study:

• To investigate parameters influencing the final intracranial catheter position in external ventricular drainage (EVD).
• To evaluate the accuracy and safety of the freehand EVD application technique.

Main Methods:

• Analysis of 100 pre- and postprocedural thin-layer computed tomography (CT) scans from EVD patients.
• Utilized JiveX® and OsiriX Lite® software for detailed assessment.
• Correlated anatomical parameters (intraventricular blood, midline shift) and procedural factors (burr-hole location, catheter entrance angle) with final catheter position.

Main Results:

• Most external ventricular drainages (EVDs) achieve optimal or near-optimal positions.
• The deviation of the catheter entrance angle significantly influences malpositioning.
• Burr-hole location demonstrates variability within several centimeters around the coronary suture.

Conclusions:

• Freehand EVD application is deemed safe if intracranial anatomy is largely intact.
• Precise surface measurements and perpendicular puncturing are crucial for safe EVD placement.
• Adherence to anatomical landmarks and proper technique minimize risks associated with freehand EVD insertion.