经皮内窥镜椎间孔腰椎间盘切除术前后位和侧位透视影像中轨迹的成角误差评估。

BACKGROUND: Anteroposterior (AP) and lateral fluoroscopies are often used to evaluate the intraoperative location and angulation of the trajectory in percutaneous endoscopic transforaminal lumbar discectomy (PETLD). Although the location of the trajectory shown in fluoroscopy is absolutely accurate, the angulation is not always reliable. This study aimed to evaluate the accuracy of the angle shown in the AP and lateral fluoroscopic views. METHODS: A technical study was performed to assess the angulation errors of PETLD trajectories shown in AP and lateral fluoroscopic views. After reconstructing a lumbar CT image, a virtual trajectory was placed into the intervertebral foramen with gradient-changing coronal angulations of the cephalad angle plane (CACAP). For each angulation, virtual AP and lateral fluoroscopies were taken, and the cephalad angles (CA) of the trajectory shown in the AP and lateral fluoroscopic views, which indicated the coronal CA and the sagittal CA, respectively, were measured. The angular relationships among the real CA, CACAP, coronal CA, and sagittal CA were further demonstrated with formulae. RESULTS: In PETLD, the coronal CA is approximately equal to the real CA, with a small angle difference and percentage error, whereas the sagittal CA shows a rather large angle difference and percentage error. CONCLUSION: The AP view is more reliable than the lateral view in determining the CA of the PETLD trajectory.

背景：经皮内窥镜椎间孔腰椎间盘切除术（PETLD）中，常通过前后位（AP）和侧位透视来评估手术过程中轨迹的位置和角度。虽然透视下显示的轨迹位置绝对准确，但角度并不总是可靠的。本研究旨在评估 AP 和侧位透视视图中显示的角度的准确性。

方法：本技术研究旨在评估 AP 和侧位透视视图中 PETLD 轨迹角度的误差。在重建腰椎 CT 图像后，将虚拟轨迹置于椎间孔内，头角平面（CACAP）的冠状角有梯度变化。对于每个角度，进行虚拟 AP 和侧位透视，并测量 AP 和侧位透视视图中轨迹的头角（CA），分别表示冠状 CA 和矢状 CA。进一步用公式展示真实 CA、CACAP、冠状 CA 和矢状 CA 之间的角度关系。

结果：在 PETLD 中，冠状 CA 约等于真实 CA，角度差异和百分比误差较小，而矢状 CA 则显示出较大的角度差异和百分比误差。

结论：在确定 PETLD 轨迹的 CA 时，AP 视图比侧位视图更可靠。