非单纯性眼眶骨折眶腔容积改变与眼球内陷相关性研究方法初探基于CT图像数据的计算机辅助测量

目的应用计算机辅助三维CT影像分析系统，测量分析非单纯性眼眶骨折术前术后眶腔容积变化，为定量诊断和矫治骨折继发眼球内陷探索可行性研究方法。方法2004年10月～12月北京大学口腔医院颌面创伤中心经治的7例颅颌面创伤合并单侧非单纯性眼眶骨折。投照薄断层（0．625mm）CT，将图像数据以DICOM格式输入图像分析软件，对眼眶及眶内容物进行三维重建。描述眶腔破坏特征。测量眼球突度、原骨折和虚拟恢复眶外缘后的眶腔容积，并做术前术后比较分析。结果应用该系统可形象直观地显示眼眶畸形部位、范围。定量明确眼眶体积扩大量。在该类眼眶骨折中，骨折可波及整个眶壁。与眶缘骨折相比较，眶壁骨折与眼球内陷关系密切。术前术后比较，眼球内陷得到不同程度的改善，健患侧眼眶体积之差进一步缩小。结论基于CT图像数据的计算机图像分析系统可以清晰直观的显示出骨折眶壁畸形，以及健患侧眶腔体积的差异。球前和球后眶腔容积差可以为进一步探求眼眶破坏与眼球内陷的相关关系及量化诊断提供重要参数。

A preliminary study on CT and computer-based method for unilateral post-traumatic enophthalmos associated with impure orbital fractures

Objective To preliminarily establish a method based on CT image and 3 - dimensional software for measurement of the injured orbit volume and its correlation to post - traumatic enophthalmos. Methods The morphology and volumes of the orbital content were investigated in 7 consecutive patients with unilateral impure orbital fractures before treatment by using a 3 - dimensional software program based CT image digital data. The variety in shape and volume between the normal and the injured orbit were analysed to find the alteration of orbital region and contribute to enophthalmos. According to the results, the operations were performed. The same items were assessed postoperativly, Results The change of the shape of the injured orbit can occur at the anterior, medium and posterior orbital wall and the normal conical shape were lost. Compared with orbital rim fractures, orbital wall fractures were closely relative to posttraumatic enophthalmos. Postoperatively, all patients had an obvious improvement in appearance, the degree of enophthalmos and the difference of the orbital volume were reduced. Conclusion Computer - assisted program enables the surgeon to predict reconstructive surgical steps and to evaluate the results of the surgery.