Konofaos Petros, Thompson Rebecca Helena, Wallace Robert D
From the *Department of Plastic Surgery, and †College of Medicine, University of Tennessee Health Science Center, Memphis, TN.
Ann Plast Surg. 2017 Nov;79(5):467-472. doi: 10.1097/SAP.0000000000001135.
Porous polyethylene (PP) has been used in craniofacial reconstruction but has been primarily relegated to small and moderate size defects. This series evaluates the long-term outcomes after alloplastic reconstruction of cranial defects larger than 5 cm using PP implants.
Eighteen patients who had reconstruction of large cranial defects, owing to tumor resection or trauma, using PP implants, with at least 2 years of postoperative follow-up, were included in the study. If soft tissue coverage was inadequate, tissue expansion was planned before final cranioplasty.
The frontal region was the most common area reconstructed (n = 10). Four patients required tissue expansion owing to soft tissue deficit. The major complication observed was implant exposure, seen in 3 patients (15%). Two of these healed with local wound care; 1 required removal of the implant. A statistically significant difference in risk of implant exposure was observed when tissue expansion was employed in reconstruction (P = 0.001).
This study confirms the material's low rate of infection and extrusion even in large craniofacial defects. Its neuroprotection properties are comparable with other first line alloplastic materials used for cranioplasty. Moreover, it can be shaped as required, there is no resorption with time and no concern for donor site morbidity. The higher exposure rate, in cases in which tissue expansion was also used, was owing to the poor quality of the soft tissue overlying the defect. These qualities make it an attractive option in alloplastic cranioplasty.
多孔聚乙烯（PP）已用于颅面重建，但主要用于中小型缺损。本系列研究评估了使用PP植入物对大于5 cm的颅骨缺损进行异体材料重建后的长期效果。
本研究纳入了18例因肿瘤切除或外伤使用PP植入物重建大型颅骨缺损且术后随访至少2年的患者。如果软组织覆盖不足，则在最终颅骨成形术前计划进行组织扩张。
额部是最常进行重建的区域（n = 10）。4例患者因软组织缺损需要进行组织扩张。观察到的主要并发症是植入物外露，3例患者（15%）出现此情况。其中2例经局部伤口护理愈合；1例需要取出植入物。在重建中采用组织扩张时，观察到植入物外露风险存在统计学显著差异（P = 0.001）。
本研究证实即使在大型颅面缺损中，该材料的感染和挤出率也较低。其神经保护特性与用于颅骨成形术的其他一线异体材料相当。此外，它可根据需要塑形，不会随时间吸收，也无需担心供区并发症。在同时使用组织扩张的病例中，较高的外露率是由于缺损上方软组织质量较差。这些特性使其成为异体材料颅骨成形术中一个有吸引力的选择。
