Non-invasive CT-based simulation of third ventricle puncture: Identifying optimal surface landmark-guided...

The third ventricle is surrounded by critical deep brain nuclei, making direct cannulation a high-risk procedure with a substantial likelihood of complications. These risks have limited systematic clinical investigation of third-ventricle puncture techniques. CT-based virtual simulation offers a promising non-invasive alternative. Although prior studies have explored CT-based simulation for lateral ventricular access, most rely on proprietary navigation software, limiting their broader applicability. In this study, we propose a non-invasive simulation framework for third-ventricle puncture based on CT imaging and the open-source platform 3D Slicer.

CT datasets from 155 adult patients were processed using 3D Slicer to reconstruct patient-specific cranial anatomy and generate virtual puncture trajectories. Eight frontal entry points were evaluated in combination with three sagittal targeting strategies based on surface anatomical landmarks: nasion-lambda (NL), medial canthi midpoint-lambda (ML), and rinion-lambda (RL). The probability of each trajectory successfully reaching the third ventricle was analyzed.

The reconstructed trajectories demonstrated that when the entry point was located 1.5 cm anterior to the coronal suture and 2.5 cm lateral to the midline, the probability of successful third-ventricle access was highest for the RL trajectory (99%), followed by ML (97%) and NL (83%).

CT-based trajectory reconstruction using the open-source 3D Slicer platform provides a feasible, safe, and cost-effective approach for studying third-ventricle puncture. This method is particularly advantageous in resource-limited settings and in research scenarios where recruitment for invasive procedures is challenging.