用于脊柱手术椎弓根螺钉置入质量保证的已知组件三维-二维配准
Known-component 3D-2D registration for quality assurance of spine surgery pedicle screw placement.
作者信息
Uneri A, De Silva T, Stayman J W, Kleinszig G, Vogt S, Khanna A J, Gokaslan Z L, Wolinsky J-P, Siewerdsen J H
机构信息
Department of Computer Science, Johns Hopkins University, Baltimore, MD 21218, USA.
出版信息
Phys Med Biol. 2015 Oct 21;60(20):8007-24. doi: 10.1088/0031-9155/60/20/8007. Epub 2015 Sep 30.
A 3D-2D image registration method is presented that exploits knowledge of interventional devices (e.g. K-wires or spine screws-referred to as 'known components') to extend the functionality of intraoperative radiography/fluoroscopy by providing quantitative measurement and quality assurance (QA) of the surgical product. The known-component registration (KC-Reg) algorithm uses robust 3D-2D registration combined with 3D component models of surgical devices known to be present in intraoperative 2D radiographs. Component models were investigated that vary in fidelity from simple parametric models (e.g. approximation of a screw as a simple cylinder, referred to as 'parametrically-known' component [pKC] registration) to precise models based on device-specific CAD drawings (referred to as 'exactly-known' component [eKC] registration). 3D-2D registration from three intraoperative radiographs was solved using the covariance matrix adaptation evolution strategy (CMA-ES) to maximize image-gradient similarity, relating device placement relative to 3D preoperative CT of the patient. Spine phantom and cadaver studies were conducted to evaluate registration accuracy and demonstrate QA of the surgical product by verification of the type of devices delivered and conformance within the 'acceptance window' of the spinal pedicle. Pedicle screws were successfully registered to radiographs acquired from a mobile C-arm, providing TRE 1-4 mm and <5° using simple parametric (pKC) models, further improved to <1 mm and <1° using eKC registration. Using advanced pKC models, screws that did not match the device models specified in the surgical plan were detected with an accuracy of >99%. Visualization of registered devices relative to surgical planning and the pedicle acceptance window provided potentially valuable QA of the surgical product and reliable detection of pedicle screw breach. 3D-2D registration combined with 3D models of known surgical devices offers a novel method for intraoperative QA. The method provides a near-real-time independent check against pedicle breach, facilitating revision within the same procedure if necessary and providing more rigorous verification of the surgical product.
本文提出了一种三维-二维图像配准方法,该方法利用介入设备(如克氏针或脊柱螺钉,称为“已知部件”)的知识,通过提供手术产品的定量测量和质量保证(QA)来扩展术中放射成像/荧光透视的功能。已知部件配准(KC-Reg)算法使用稳健的三维-二维配准,并结合术中二维放射照片中已知存在的手术设备的三维部件模型。研究了保真度不同的部件模型,从简单的参数模型(如将螺钉近似为简单圆柱体,称为“参数已知”部件[pKC]配准)到基于特定设备CAD图纸的精确模型(称为“精确已知”部件[eKC]配准)。使用协方差矩阵自适应进化策略(CMA-ES)解决了来自三张术中放射照片的三维-二维配准问题,以最大化图像梯度相似度,从而确定设备相对于患者术前三维CT的放置位置。进行了脊柱模型和尸体研究,以评估配准精度,并通过验证所植入设备的类型以及在椎弓根“接受窗口”内的一致性来证明手术产品的质量保证。使用简单的参数(pKC)模型,椎弓根螺钉成功与从移动C形臂获取的放射照片配准,平均配准误差(TRE)为1-4毫米,角度偏差小于5°,使用eKC配准进一步提高到小于1毫米和小于1°。使用先进的pKC模型,检测出与手术计划中指定的设备模型不匹配的螺钉的准确率超过99%。相对于手术计划和椎弓根接受窗口的已配准设备的可视化提供了潜在有价值的手术产品质量保证,并可靠地检测出椎弓根螺钉穿破。三维-二维配准与已知手术设备的三维模型相结合,为术中质量保证提供了一种新方法。该方法提供了一种近乎实时的针对椎弓根穿破的独立检查,如有必要便于在同一手术过程中进行修正,并为手术产品提供更严格的验证。