The Study of the New Occipital Ventricle Entry Point Using 3D-CT Simulation

Abstract

Background: Cerebrospinal fluid diversion procedures are perhaps the most common procedure in neurosurgery, which is sometimes accessed via a posterior approach. However, there are many variations either in entry points, trajectories, and questions for their clinical outcomes. This study aimed to reevaluate commonly used posterior approach entry points based on 3-dimensional computed tomography (3D-CT) technology.
Method: A total of 180 patients who were diagnosed with hydrocephalus were retrieved and craniometric evaluation was done with reconstruction technique for thin cut 3D-CT. Cartesian coordinates of the new entry point for posterior ventricular catheter insertion (or the “New occipital entry point” in this study) were calculated and the brain parenchymal thickness that is traversed by the catheter via three approaches (Keen’s, Frazier’s, and our New occipital entry point) were compared.
Result: The New occipital entry point for posterior ventricular catheter placement is approximately 4 cm above the inion and 6 cm from the midline for both the right and left sides. The traversed brain parenchymal thickness for the New occipital entry point was statistically significantly less than Frazier’s point on both sides (P < 0.001) but more than that of Keen’s point, with statistically significance on both sides (P < 0.001 for right side and P = 0.006 for left side). Keen’s point may have the least traversed brain parenchymal thickness but it might be difficult to access when the patient is set in a prone position.
Conclusion: Our study showed that the New occipital ventricle entry point for the posterior ventricular approach may decrease the amount of brain parenchymal traversed from catheter insertion. Clinical trials in real patients are needed for further evaluation of this entry point.