针对婴幼儿颅缝早闭的颅骨重塑手术模拟方法

Simulation method of skull remodellingsurgeryfor infant with craniosynostosis

婴幼儿颅缝早闭引起的颅面畸形严重影响着婴幼儿正常发育。针对婴幼儿颅缝早闭的颅骨重塑手术的目的是颅骨的扩容和美观,目前颅骨重塑手术没有标准规范的切割和拼接方案,而且对于术后效果缺乏合理的评估。针对这一难题,本文以矢状缝早闭导致的舟状头为对象,通过对舟状头的形态特征分析,将患儿颅骨畸变区域与理想颅骨模型进行点云配准,生成颅骨切割与错位拼接方案;建立婴幼儿颅骨生长有限元模型,预测颅骨重塑术后生长趋势;最后以一位典型矢状缝早闭患儿为例进行了模拟手术的实验研究。评估结果显示该切割拼接方案有效地改善了颅骨发育异常部位的形态,并具有理想的生长趋势。本文所研究患儿的术前头颅指数(CI)为65.31%,经过9个月的生长模拟后增长至71.50%。颅骨重塑方案的模拟给后期手术方案设计提供了参考标准。该方案能够大幅度改善术后效果,可以推广至其他类型颅缝早闭手术的切割拼接方案生成与术后效果评价。

Craniofacial malformation caused by premature fusion of cranial suture of infants has a serious impact on their growth. The purpose of skull remodeling surgery for infants with craniosynostosis is to expand the skull and allow the brain to grow properly. There are no standardized treatments for skull remodeling surgery at the present, and the postoperative effect can be hardly assessed reasonably. Children with sagittal craniosynostosis were selected as the research objects. By analyzing the morphological characteristics of the patients, the point cloud registration of the skull distortion region with the ideal skull model was performed, and a plan of skull cutting and remodeling surgery was generated. A finite element model of the infant skull was used to predict the growth trend after remodeling surgery. Finally, an experimental study of surgery simulation was carried out with a child with a typical sagittal craniosynostosis. The evaluation results showed that the repositioning and stitching of bone plates effectively improved the morphology of the abnormal parts of the skull and had a normal growth trend. The child’s preoperative cephalic index was 65.31%, and became 71.50% after 9 months’ growth simulation. The simulation of the skull remodeling provides a reference for surgical plan design. The skull remodeling approach significantly improves postoperative effect, and it could be extended to the generation of cutting and remodeling plans and postoperative evaluations for treatment on other types of craniosynostosis.