During craniotomies, a portion of the calvarium or skull is removed to gain access to the intracranial space. When it is not possible to re-implant the flap, surgeons may repair the defect intraoperatively or at a later date. With larger defects being more difficult to repair intraoperatively, we investigated a method for the creation of patient-specific moulds for ad hoc bone flap reconstruction using rapid prototyping. Patient-specific moulds were created based on light scanned models of the defect, using custom software and rapid prototyping. Polymethylmethacrylate bone implants were created for three retrospective craniotomy cases and evaluated based on original flap and skull reconstruction accuracy. Bone implants created using our moulding method reconstruct the original flap and skull with an average reconstruction accuracy of 0.82 and 1.3 mm, respectively. Average skull reconstruction accuracy obtained by surgeons performing freehand implant reconstruction was 1.49 mm. Time needed to generate moulds was between 2 h and 45 min and 6 h and 20 min. Improvements to current printing technology will make this procedure technically feasible for future cranial procedures.

在开颅手术中，颅骨或颅骨的一部分被移除以进入颅内空间。当无法重新植入皮瓣时，外科医生可能会在术中或以后修复缺损。由于较大的缺损在术中更难修复，因此我们研究了一种使用快速原型制作特殊骨瓣重建患者特定模具的方法。基于缺陷的光扫描模型，使用定制软件和快速原型制作特定于患者的模具。为三个回顾性开颅手术病例制作了聚甲基丙烯酸甲酯骨植入物，并根据原始皮瓣和颅骨重建的准确性进行了评估。使用我们的成型方法创建的骨植入物以 0.82 和 1 的平均重建精度重建原始皮瓣和颅骨。分别为 3 毫米。外科医生进行徒手种植体重建获得的平均颅骨重建精度为 1.49 毫米。生成模具所需的时间介于 2 小时至 45 分钟和 6 小时至 20 分钟之间。对当前打印技术的改进将使该程序在技术上适用于未来的颅骨手术。