Penney Graeme P, Edwards Philip J, Hipwell John H, Slomczykowski Mike, Revie Ian, Hawkes David J
Imaging Sciences Division, Guy's King's and St Thomas' Schools of Medicine, Kings College London, London SEI 3RB, UK.
IEEE Trans Biomed Eng. 2007 Jul;54(7):1342-8. doi: 10.1109/TBME.2007.890737.
A method to accurately measure the position and orientation of an acetabular cup implant from postoperative X-rays has been designed and validated. The method uses 2-D-3-D registration to align both the prosthesis and the preoperative computed tomography (CT) volume to the X-ray image. This allows the position of the implant to be calculated with respect to a CT-based surgical plan. Experiments have been carried out using ten sets of patient data. A conventional plain-film measurement technique was also investigated. A gold standard implant position and orientation was calculated using postoperative CT. Results show our method to be significantly more accurate than the plain-film method for calculating cup anteversion. Cup orientation and position could be measured to within a mean absolute error of 1.4 mm or degrees.
一种从术后X射线精确测量髋臼杯植入物位置和方向的方法已经设计并得到验证。该方法使用二维到三维配准，将假体和术前计算机断层扫描（CT）容积与X射线图像对齐。这使得可以根据基于CT的手术计划计算植入物的位置。已经使用十组患者数据进行了实验。还研究了传统的平片测量技术。使用术后CT计算了金标准植入物位置和方向。结果表明，在计算髋臼前倾角方面，我们的方法比平片方法明显更准确。髋臼的方向和位置测量平均绝对误差可控制在1.4毫米或度以内。
