Kozakiewicz Marcin
Department of Maxillofacial Surgery (Head: Marcin Kozakiewicz, DDS, PhD), Medical University of Lodz, Zeromskiego 113, Lodz, Poland.
J Craniomaxillofac Surg. 2014 Jun;42(4):283-9. doi: 10.1016/j.jcms.2013.05.015. Epub 2013 Jul 5.
Despite of well-known advantages of high molecular weight polyethylene (Medpor, Synpore) in orbital reconstructions, the thickness of those implants significantly exceeds 0.5 mm and precise modification of thickness is limited. The aim of this study was to present the application of a self-developed method of treatment orbital wall fracture by custom implant made of ultrahigh molecular weight polyethylene (UHMW-PE).
First, the test of influence of sterilization process upon implant deformation was performed (autoclaving, ethylene oxide, gas plasma, irradiation). Next, ten cases for delayed surgical treatment of orbital fracture were included into this study (7 males, 3 females). Based on CT scan and mirrored technique, a CAD model of virtual implant for repairing orbital wall was made. Then, an implant was manufactured with a computer numerical controlled milling machine from UHMW-PE block, sterilized and used during a surgical procedure. Clinically used implants had thickness from 0.2 to 4.0 mm.
The best method of sterilization is ethylene oxide process, and the worst is autoclaving. In this series of delayed surgical cases, functional results of orbital surgery are worse than in simpler, early treated cases, but long-term subsidence of diplopia is noticeable [10% poor results]. The results of the treatment depend on the initial level of diplopia where severe initial diplopia to be corrected requires thicker implants (p < 0.01). It also leads to longer surgical procedures (p < 0.01), but prolongation of the surgery had no negative influence upon results of any investigated follow-up examinations. Obviously, the orbital destruction intensity is related to injury-evoked initial diplopia but it also influences whole results of treatment up to 12 months post-op. Interesting result is presented by the relation of maximal implant thickness to 12-month diplopia evaluation. Thicker implants used result in lower residual diplopia (p < 0.05). This is important because of the correlation between the higher orbital destruction intensity with a thicker UHMW-PE implant (p < 0.05) applied in this series.
Patient-specific ultrahigh molecular weight polyethylene implants enable precise reconstructions of orbital wall. One should not be afraid of a significant eye globe reposition caused by these thickness modulated implants, as such repositioning is essential for an efficient correction of enophthalmos.
尽管高分子量聚乙烯（Medpor、Synpore）在眼眶重建中有众所周知的优点，但这些植入物的厚度明显超过0.5毫米，且厚度的精确调整有限。本研究的目的是介绍一种自行开发的方法，即使用超高分子量聚乙烯（UHMW-PE）定制植入物治疗眼眶壁骨折。
首先，进行了灭菌过程对植入物变形影响的测试（高压灭菌、环氧乙烷、气体等离子体、辐照）。接下来，本研究纳入了10例眼眶骨折延迟手术治疗的病例（7例男性，3例女性）。基于CT扫描和镜像技术，制作了修复眼眶壁的虚拟植入物CAD模型。然后，用计算机数控铣床从UHMW-PE块制造植入物，灭菌后在手术过程中使用。临床使用的植入物厚度为0.2至4.0毫米。
最佳灭菌方法是环氧乙烷处理，最差的是高压灭菌。在这一系列延迟手术病例中，眼眶手术的功能结果比简单的早期治疗病例差，但复视的长期消退很明显[10%效果不佳]。治疗结果取决于初始复视水平，严重的初始复视需要更厚的植入物来矫正（p<0.01）。这也导致手术时间更长（p<0.01），但手术时间延长对任何调查的随访检查结果没有负面影响。显然，眼眶破坏强度与损伤引起的初始复视有关，但它也会影响术后12个月的整体治疗结果。最大植入物厚度与12个月复视评估的关系呈现出有趣的结果。使用更厚的植入物会导致更低的残余复视（p<0.05）。这很重要，因为在本系列中应用的UHMW-PE植入物厚度越大，眼眶破坏强度越高（p<0.05）。
定制的超高分子量聚乙烯植入物能够精确重建眼眶壁。不应担心这些厚度可调的植入物会导致眼球明显复位，因为这种复位对于有效矫正眼球内陷至关重要。
