Background An orbital implant is used after enucleation or evisceration surgery to replace the volume lost and to aid in prosthesis fitting and movement. Different materials have been used through the years. The authors noted that with bone-derived hydroxyapatite orbital implants, some patients lose their orbital volume. Methods The operating theatre record was searched to find patients who had their hydroxyapatite orbital implant removed at Dunedin Hospital, New Zealand, between 2011 and 2015. The original implant size and size at removal were noted. Histological results were noted. Medical notes were reviewed. Results A total of six patients had hydroxyapatite orbital implants removed during this time. Four patients had implants that were smaller than their original sizes. All specimens had fibrovascular infiltration noted, three had chronic inflammatory cells and one had osteoclastic activity. Conclusions Bone-derived hydroxyapatite orbital implants can reduce in size, and this may occur due to osteoclastic activity. The surgeon must consider this scenario when choosing the type of implant to be used after enucleation or evisceration. All data relevant to the study are included in the article or uploaded as supplementary information.

中文翻译：

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缩小羟基磷灰石眶内植入物案例系列

背景 在摘除或内脏手术后使用眼眶植入物来补充丢失的体积并帮助假体装配和移动。多年来使用了不同的材料。作者指出，使用骨衍生的羟基磷灰石眼眶植入物，一些患者会失去眼眶体积。方法 搜索手术室记录，寻找 2011 年至 2015 年间在新西兰但尼丁医院移除羟基磷灰石眼眶植入物的患者。记录原始植入物尺寸和移除时的尺寸。记录了组织学结果。审查了医疗记录。结果 在此期间共有 6 名患者移除了羟基磷灰石眼眶植入物。四名患者的植入物小于其原始尺寸。所有标本均有纤维血管浸润，三个有慢性炎症细胞，一个有破骨细胞活性。结论 骨源性羟基磷灰石眼眶植入物可以缩小尺寸，这可能是由于破骨细胞活性所致。外科医生在选择摘除或取出内脏后使用的植入物类型时必须考虑这种情况。所有与研究相关的数据都包含在文章中或作为补充信息上传。