16层螺旋CT多平面重组和容积再现图像在中足跖跗骨复杂骨折中的临床应用价值

目的评价16层螺旋CT多平面重建(MPR)与容积再现(VR)对中足复杂骨折的诊断价值。方法 18例中足骨骨折患者先经X线平片(DR)和常规轴位CT扫描,而后将容积数据传送至工作站进行MPR与VR三维重建,并与DR及常规轴位CT比较。结果 18例中有中足跖跗骨折76处,其中64处骨折累及跖跗关节面。在DR像上,10例跖跗骨折为阴性,其余8例仅显示18处骨折,显示率为23.7%。常规轴位CT像显示骨折60处,显示率为78.9%。MPR对跖跗骨折的显示率为100%。VR图像对足舟骨、骰骨、跖骨及楔骨骨折的显示率分别为100%、75%、70.9%及60%,平均显示率为68.4%。VR图像能通过图像多角度旋转观察骨折细节,对怀疑累及关节面的骨折,利用勾画、删除技术及多方位切割技术对中足骨进行分离、重组、单独显示关节面情况。结论利用16层螺旋CT的MPR结合VR图像能显著提高中足跖跗骨折,尤其是深部骨折的诊断准确性。

Applied value of 16-slice spiral CT with MPR and VR in diagnosing the complicated fractures of midfoot tarsometatarsus bones

Objective To assess the applied value of 16-slice spiral CTwith multiplanar reconstruction（MPR） and volume rendering（VR） in diagnosing the complicated fractures of tarsometatarsus bones.Methods 18 patients with tarsometatarsal fracture underwent initially diagital radiography（DR） and conventional axial CT scaning.Subsequently,the volume data were transferred in to the workstation and postprocessed by MPR and VR and compared with DR and axial CT.Results There were 76 sites of tarsometatarsal fractures in 18 patients,which comprised 64 sites involving into the articular surface.On DR images,tarsometatarsal fractures in 10 patients were negative,while remainder 8 patients had only 18 sited of tarsometatarsal fractures,the detection rate was 23.7%.Axial CT scans showed 60 sites of tarsometatarsal fractures with a detection rate of 78.9%.MPR showed all 76 sited of tarsometatarsal fractures with a detection rate of 100%.The detection rate of VR for navicular,cuboid,metatarsal and cuneiform bone fracture were 100%,75%,70.9%and 60%,respectively.The mean of detection rate was 68.4%.The fracture details could be observed through multiangular image rotation with VR.Also depicting,removing and multidirectional cutting techniques could perform the detachment and reformation of midfeet bones in order to show the articular surface alone patients for suspected articular surface incolvement.Conclusion 16-slice spiral CT MPR combined with VR can significantly elevate the diagnosic accuracy of tarsometatarsal fractures,especially deep fractures.