基于混合现实的三维测量技术辅助诊断颅底凹陷症

Diagnosis of basilar invagination with assistance of 3D measurement technique based on mixed reality

目的寻找基于混合现实的新型颅底凹陷症三维测量技术。方法选取19例颅底凹陷症患者的CT扫描数据(观察组),通过混合现实医学影像系统建立颅底-颈椎三维混合现实模型,确定枕骨大孔出口切面,判断齿突与该切面是否相交,测量枢椎齿突平均陷入体积和高度;同时对Chamberlain线和McGregor线等二维矢状面影像学指标进行测量。取同期19例正常人CT数据(对照组),分析两组测量结果,计算二维、三维测量指标的假阳性率和假阴性率。结果三维测量齿突平均陷入体积(456.0±141.2)mm^3,平均陷入高度(4.6±1.3)mm;无假阳性结果,假阴性率5%(1/19)。Chamberlain线二维测量假阳性率11%(2/19),假阴性率16%(3/19);McGregor线测量假阳性率5%(1/19),假阴性率26%(5/19)。结论基于混合现实的新型三维测量技术结果可靠,可用于辅助颅底凹陷症的影像学诊断。

Objective To find a new 3D measurement technique based on mixed reality for basilar invagination.Methods CT data of 19 patients with basilar invagination were selected as observation group,and were used to construct skull base-cervical vertebrae 3D mixed reality model by Mixed Reality Medical Image System.The cut of the outlet of foramen magnum was determined,the odontoid process intersected the cut was evaluated,and the mean volume and height of the convex odontoid tubercle were calculated.Meanwhile,2D sagittal image indexes such as Chamberlain line and McGregor line were measured.CT data from 19 normal people at the same period were also selected as control group,measurement results in two groups were analyzed,and the false positive and negative rates of 2D or 3D indexes were calculated.Results The 3D measurements,mean volume and height of convex odontoid tubercle were(456.0±141.2)mm3 and(4.6±1.3)mm respectively,there was no false positive result and the false negative rate was 5%(1/19);When chamberlain line and McGregor line measurements were used,the false positive rate was 11%(2/19),5%(1/19)and the false negative rate was 16%(3/19),26%(5/19)respectively.Conclusion New 3D measurement technique based on mixed reality could be used to assist the imaging diagnosis for basilar invagination due to its reliable results.