Takao Masaki, Nishii Takashi, Sakai Takashi, Sugano Nobuhiko
Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
Comput Aided Surg. 2012;17(2):69-76. doi: 10.3109/10929088.2012.654823.
The aim of this study was to find the proper location of the fluoroscopic imaging center in order to apply a CT-based 3D fluoroscopy matching navigation system in the pelvic and femoral regions.
To simulate surgeries around the hip joint, a dry human pelvis and femur were used. A total of 16 fiducial markers, each consisting of a metal ball 1.5 mm in diameter, were fixed to the pelvis and femur. For the pelvis, the pubic symphysis, the acetabular fossa, and a site on the ilium 3 cm above the acetabular roof were selected as fluoroscopic imaging centers. For the proximal femur, the base of the femoral neck, the femoral shaft at the level of the lesser trochanter, and the inferior border of the great trochanter were selected as fluoroscopic imaging centers.
Target registration error (TRE) differed significantly among the selected fluoroscopic imaging centers. The best mean TRE for the pelvis was 0.8 mm (range: 0.2 to 1.6 mm) with the imaging center on the ilium (3 cm above the acetabular roof). The best mean TRE for the proximal femur was 1.1 mm (range: 0.2 to 2.0 mm) with the imaging center on the femoral shaft at the lesser trochanter level.
Fluoroscopic imaging center location had a significant effect on the accuracy of the CT-based 3D fluoroscopy matching navigation system in the pelvic and femoral regions. The proper fluoroscopic imaging centers for CT-3D fluoroscopic matching were, for the pelvis, a site on the ilium 3 cm above the acetabular roof, and for the proximal femur, the femoral shaft at the level of the lesser trochanter.
本研究旨在确定透视成像中心的合适位置，以便在骨盆和股骨区域应用基于CT的三维透视匹配导航系统。
为模拟髋关节周围手术，使用了一具干燥的人体骨盆和股骨。总共16个基准标记物，每个由直径1.5毫米的金属球组成，被固定在骨盆和股骨上。对于骨盆，选择耻骨联合、髋臼窝以及髋臼顶上方3厘米处的髂骨部位作为透视成像中心。对于股骨近端，选择股骨颈基部、小转子水平处的股骨干以及大转子下缘作为透视成像中心。
在所选的透视成像中心中，目标配准误差（TRE）存在显著差异。骨盆的最佳平均TRE为0.8毫米（范围：0.2至1.6毫米），成像中心位于髂骨（髋臼顶上方3厘米处）。股骨近端的最佳平均TRE为1.1毫米（范围：0.2至2.0毫米），成像中心位于小转子水平处的股骨干。
透视成像中心的位置对基于CT的三维透视匹配导航系统在骨盆和股骨区域的准确性有显著影响。对于CT-3D透视匹配而言，合适的透视成像中心，对于骨盆是髋臼顶上方3厘米处的髂骨部位，对于股骨近端是小转子水平处的股骨干。
