Department of Orthopaedic Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
J Neurosurg Spine. 2011 Nov;15(5):479-85. doi: 10.3171/2011.6.SPINE10721. Epub 2011 Jul 15.
Use of computer-assisted spine surgery (CASS) technologies, such as navigation systems, to improve the accuracy of pedicle screw (PS) placement is increasingly popular. Despite of their benefits, previous CASS systems are too expensive to be ubiquitously employed, and more affordable and portable systems are desirable. The aim of this study was to introduce a novel and affordable computer-assisted technique that 3-dimensionally visualizes anatomical features of the pedicles and assists in PS insertion. The authors have termed this the 3D-visual guidance technique for inserting pedicle screws (3D-VG TIPS).
The 3D-VG technique for placing PSs requires only a consumer-class computer with an inexpensive 3D DICOM viewer; other special equipment is unnecessary. Preoperative CT data of the spine were collected for each patient using the 3D-VG TIPS. In this technique, the anatomical axis of each pedicle can be analyzed by volume-rendered 3D models, as with existing navigation systems, and both the ideal entry point and the trajectory of each PS can be visualized on the surface of 3D-rendered images. Intraoperative guidance slides are made from these images and displayed on a TV monitor in the operating room. The surgeon can insert PSs according to these guidance slides. The authors enrolled 30 patients with adolescent idiopathic scoliosis (AIS) who underwent posterior fusion with segmental screw fixation for validation of this technique.
The novel technique allowed surgeons, from office or home, to evaluate the precise anatomy of each pedicle and the risks of screw misplacement, and to perform 3D preoperative planning for screw placement on their own computer. Looking at both 3D guidance images on a TV monitor and the bony structures of the posterior elements in each patient in the operating theater, surgeons were able to determine the best entry point for each PS with ease and confidence. Using the current technique, the screw malposition rate was 4.5% in the thoracic region in corrective surgery for AIS.
The authors found that 3D-VG TIPS worked on a consumer-class computer and easily visualized the ideal entry point and trajectory of PSs in any operating theater without costly special equipment. This new technique is suitable for preoperative planning and intraoperative guidance when performing reconstructive surgery with PSs.
使用计算机辅助脊柱手术（CASS）技术，如导航系统，来提高椎弓根螺钉（PS）放置的准确性，这种技术越来越受欢迎。尽管它们有很多好处，但以前的 CASS 系统过于昂贵，无法广泛应用，因此需要更经济实惠且便携的系统。本研究旨在介绍一种新的、经济实惠的计算机辅助技术，该技术可以三维可视化椎弓根的解剖特征，并辅助 PS 插入。作者将其命名为椎弓根螺钉三维可视化引导技术（3D-VG TIPS）。
椎弓根螺钉放置的 3D-VG 技术仅需要一台具有廉价 3D DICOM 查看器的消费级计算机；不需要其他特殊设备。使用 3D-VG TIPS 为每位患者采集脊柱术前 CT 数据。在该技术中，与现有的导航系统一样，可以通过体积渲染的 3D 模型分析每个椎弓根的解剖轴，并且可以在 3D 渲染图像的表面上可视化每个 PS 的理想进钉点和轨迹。术中引导幻灯片由这些图像制成，并在手术室的电视监视器上显示。外科医生可以根据这些引导幻灯片插入 PS。作者纳入了 30 例接受后路融合节段性螺钉固定治疗青少年特发性脊柱侧凸（AIS）的患者，以验证该技术。
该新技术使外科医生可以在办公室或家中评估每个椎弓根的精确解剖结构和螺钉放置位置不当的风险，并在自己的计算机上进行螺钉放置的三维术前规划。外科医生在手术室中通过查看 TV 监视器上的 3D 引导图像和每个患者的后柱骨性结构，能够轻松、自信地确定每个 PS 的最佳进钉点。使用目前的技术，在 AIS 的矫正手术中，胸椎区域螺钉位置不当的发生率为 4.5%。
作者发现 3D-VG TIPS 可以在消费级计算机上运行，并且可以在没有昂贵特殊设备的任何手术室中轻松可视化 PS 的理想进钉点和轨迹。这种新技术适用于 PS 重建手术的术前规划和术中引导。
