Patient-specific interactive software module for virtual preoperative planning and visualization of pedicle screw entry point and trajectories in spine surgery

• Published in: Neurology India Vol. 66; no. 6; pp. 1766 - 1770
• Main Authors: Muralidharan, Vetrivel, Swaminathan, Ganesh, Devadhas, Devakumar, Joseph, Baylis
• Format: Journal Article
• Language: English
• Published: India Wolters Kluwer India Pvt. Ltd 01.11.2018; Medknow Publications and Media Pvt. Ltd; Medknow Publications & Media Pvt. Ltd
• Subjects: Analysis; CAT scans; Healthcare industry software; Humans; Image processing; Image processing software; Lumbar Vertebrae - surgery; Medical imaging; Medical imaging equipment; Open source software; Pedicle Screws; Planning; Preoperative Care; Preoperative Period; Software; Spinal Fusion - methods; Spinal surgery; Surgeons; Surgery; Tomography; Vertebrae; Visualization; Visualization (Computer); United States > US; and identifies the ideal entry points; Pedicle screw; spine surgeryKey Message: An interactive software module has been proposed that provides orientation of each vertebra in three-dimensions; preoperative planning; angles of insertion and trajectories for lumbar pedicle screw insertion; spine surgery
• ISSN: 0028-3886; 1998-4022
• DOI: 10.4103/0028-3886.246281

Background: Lumbar pedicle screw insertion involves a steep learning curve for novice spine surgeons and requires image guidance or navigation. Small volume centers may be handicapped by the lack of cost-effective user-friendly tools for preoperative planning, guidance, and decision making. Objective: We describe a patient-specific interactive software module, pedicle screw simulator (PSS), for virtual preoperative planning to determine the entry point and visualize the trajectories of pedicle screws. Materials and Methods: The PSS was coded in Python for use in an open source image processing software, 3D Slicer. Preoperative computed tomography (CT) data of each subject was loaded into this module. The entry-target (ET) mode calculates the ideal angle from the entry point through the widest section of the pedicle to the desired target in the vertebral body. The entry-angle (EA) mode projects the screw trajectory from the desired entry point at a desired angle. The performance of this software was tested using CT data from four subjects. Results: PSS provided a quantitative and qualitative feedback preoperatively to the surgeon about the entry point and trajectories of pedicle screws. It also enabled the surgeons to visualize and predict the pedicle breach with various trajectories. Conclusion: This interactive software module aids in understanding and correcting the orientation of each vertebra in three-dimensions, to identify the ideal entry points, angles of insertion and trajectories for pedicle screw insertion to suit the local anatomy.