枕下乙状窦后入路显露颈静脉孔区的虚拟现实模拟研究

Simulation of jugular foramen region exposure through suboccipito-retrosigmoidal approach by virtual reality system

目的利用虚拟现实技术模拟人体枕下乙状窦后入路显露颈静脉孔区的局部解剖特征。方法 5例成人尸体头颅行头颅CT和MRI扫描,动脉系统和静脉系统依次灌注混合造影剂乳胶。分别于2次灌注后再次行头颅CT扫描。按照枕下乙状窦后入路解剖两侧尸体头颅,切除部分小脑半球显露脑干和颅神经,再次行头颅MRI扫描,影像数据输入Vitrea虚拟现实系统构建颈静脉孔区三维解剖模型并且模拟枕下乙状窦后入路。分别于尸体头颅和计算机模型中选择内听道入口上缘,颈静脉孔前缘,颈静脉孔后缘为骨性标志点测量距离,采用Bland-Altman方法进行测量结果一致性检验。结果虚拟现实颈静脉孔区三维解剖模型中神经、血管和骨性结构的空间关系清晰显示,尸体头颅标本和计算机模型中测量内听道入口上缘-颈静脉孔前缘、内听道入口上缘-颈静脉孔后缘以及颈静脉孔前后缘之间连线距离,经BlandAltman检验,偏倚分别为0.060、0.062和0.017,95%可信区间分别为-0.255~0.375、-0.357~0.481和-0.265~0.299,绘制散点图显示一致性良好。结论颈静脉孔区的三维解剖模型数据测量经尸体头颅解剖验证其准确性良好。

Objective To demonstrate the regional anatomy features of jugular foramen region in suboccipito-retrosigmoidal approach simulated by virtual reality technique.Methods CT and MRI scanning were performed to 5 adult cadaver heads,and then,silicone mixed with contrast agent was injected into the arterial and venous systems respectively.CT scanning were performed again after above 2 times of injection.Brainstem and cranial nerves were exposed after resecting partial cerebellar hemisphere by suboccipito-retrosigmoidal approach in the bilateral dissection of cadaver head.MRI scaning were performed again.Image data was inputted into Vitrea virtual reality system to establish three-dimensional anatomy model of jugular foramen region and simulate suboccipito-retrosigmoidal approach.Superior margin of inner acoustic canal entrance,anterior and posterior margin of jugular foramen were selected as osseous mark points to measure the distance in cadaver heads and computed models respectively.Bland-Altman method was used for the uniformity of checking.Results Spacial relationships of nerves,vessels and osseous structures were displayed well in virtual reality three-dimensional model of jugular foramen region.Comparative analysis between cadaver heads and computed models by Bland-Altman method showed that bias for distance between superior margin of inner acoustic canal entrance and anterior margin of jugular foramen,superior margin of inner acoustic canal entrance and posterior margin of jugular foramen,anterior and posterior margin of jugular foramen were 0.060,0.062,and 0.017,respectively,and 95% confidence intervals were-0.255 to 0.375,-0.357 to 0.481,and-0.265 to0.299,respectively.Good consistency was demonstrated in scatter diagram.Conclusion Data measured in three-dimensional anatomic model of jugular foramen region is proven to be accurate by cadaver dissection,which is helpful to launch research for protection of nerves and vessels.