Division of Neurosurgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire.
Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire.
Oper Neurosurg (Hagerstown). 2018 Jan 1;14(1):29-35. doi: 10.1093/ons/opx132.
The use of image guidance during spinal surgery has been limited by several anatomic factors such as intervertebral segment motion and ineffective spine immobilization. In its current form, the surgical field is coregistered with a preoperative computed tomography (CT), often obtained in a different spinal confirmation, or with intraoperative cross-sectional imaging. Stereovision offers an alternative method of registration.
To demonstrate the feasibility of stereovision-mediated coregistration of a human spinal surgical field using a proof-of-principle study, and to provide preliminary assessments of the technique's accuracy.
A total of 9 subjects undergoing image-guided pedicle screw placement also underwent stereovision-mediated coregistration with preoperative CT imaging. Stereoscopic images were acquired using a tracked, calibrated stereoscopic camera system mounted on an operating microscope. Images were processed, reconstructed, and segmented in a semi-automated manner. A multistart registration of the reconstructed spinal surface with preoperative CT was performed. Registration accuracy, measured as surface-to-surface distance error, was compared between stereovision registration and a standard registration.
The mean surface reconstruction error of the stereovision-acquired surface was 2.20 ± 0.89 mm. Intraoperative coregistration with stereovision was performed with a mean error of 1.48 ± 0.35 mm compared to 2.03 ± 0.28 mm using a standard point-based registration method. The average computational time for registration with stereovision was 95 ± 46 s (range 33-184 s) vs 10to 20 min for standard point-based registration.
Semi-automated registration of a spinal surgical field using stereovision is possible with accuracy that is at least comparable to current landmark-based techniques.
在脊柱手术中使用图像引导受到了一些解剖因素的限制，如椎间节段运动和脊柱固定无效。目前，手术区域与术前计算机断层扫描（CT）进行配准，通常是在不同的脊柱确认下进行，或者与术中的横截面成像进行配准。立体视觉提供了一种替代的配准方法。
通过原理验证研究，证明使用立体视觉介导人体脊柱手术区域配准的可行性，并对该技术的准确性进行初步评估。
共有 9 名接受图像引导的椎弓根螺钉植入术的患者也接受了术前 CT 成像的立体视觉介导配准。使用安装在手术显微镜上的经过跟踪和校准的立体相机系统获取立体图像。通过半自动方式处理、重建和分割图像。对重建的脊柱表面与术前 CT 进行多起点配准。将立体视觉配准和标准配准的表面到表面距离误差进行比较，以衡量配准精度。
立体视觉获取的表面的平均表面重建误差为 2.20±0.89mm。与使用标准基于点的配准方法相比，术中使用立体视觉进行的核心配准的平均误差为 1.48±0.35mm。使用立体视觉进行配准的平均计算时间为 95±46s（范围 33-184s），而标准基于点的配准方法的平均计算时间为 10 到 20 分钟。
使用立体视觉对脊柱手术区域进行半自动配准是可行的，其准确性至少与当前基于标志点的技术相当。
