Bernard S L, Picha G J
Department of Surgery, MetroHealth Medical Center, Cleveland, Ohio.
Plast Reconstr Surg. 1991 Jan;87(1):96-105; discussion 106-7.
An animal model was developed to determine the feasibility of vascularizing a porous biomaterial and transferring it as part of a free flap to a recipient site with enhanced resistance to infection due to the maintenance of a blood supply. To that end, the experiment was divided into three stages. Stage 1 compared the soft-tissue response of Interpore-200 to Interpore-500, both continuously porous hydroxyapatite materials implanted beneath the panniculus carnosus of the male Sprague-Dawley rat. Pore size was an important factor as it influenced vascular ingrowth, with Interpore-200 vascularizing earlier (complete at 1 week) and more intensely. Interpore-200 was therefore used for the remainder of the experiment. After 1 week of tissue ingrowth, the implants were moved from the abdomen to the skull on a vascular pedicle as a "biocomposite" free flap. Stage 2 was the histologic evaluation of 15 "biocomposite" free flaps over various time intervals up to 8 months. The free flaps formed a fibrous union to the skull, while a simple nonvascularized Interpore-200 onlay graft (stage 2 control) demonstrated a bony union in three of four implants placed up to 2 months. Stage 3 confirmed the free flap's resistance to bacterial infection. A highly significant difference (p less than 0.005) in infection rates was demonstrated between the "biocomposite" and nonvascularized stage 3 controls with no Pseudomonas growth from 9 of 10 cultures of the free flaps 5 days after exposure to 10(4) Pseudomonas aeruginosa, while stage 3 controls demonstrated Pseudomonas growth in all cultures (heavy growth in 8 of 10). The "biocomposite" free flap has excellent potential to provide form and structure to wounds requiring reconstruction where bacterial contamination is a significant risk factor.
开发了一种动物模型，以确定对多孔生物材料进行血管化并将其作为游离皮瓣的一部分转移到受区的可行性，该受区因维持血液供应而对感染具有增强的抵抗力。为此，实验分为三个阶段。第一阶段比较了Interpore - 200和Interpore - 500的软组织反应，这两种材料均为连续多孔的羟基磷灰石材料，植入雄性Sprague - Dawley大鼠的腹直肌下。孔径是一个重要因素，因为它影响血管长入，Interpore - 200血管化更早（在1周时完成）且更强烈。因此，在实验的其余部分使用Interpore - 200。组织长入1周后，将植入物通过血管蒂从腹部转移到颅骨，作为“生物复合材料”游离皮瓣。第二阶段是对15个“生物复合材料”游离皮瓣在长达8个月的不同时间间隔进行组织学评估。游离皮瓣与颅骨形成纤维连接，而简单的非血管化Interpore - 200覆盖移植（第二阶段对照）在长达2个月植入的四个植入物中有三个显示出骨连接。第三阶段证实了游离皮瓣对细菌感染的抵抗力。在“生物复合材料”和非血管化的第三阶段对照之间，感染率存在高度显著差异（p小于0.005），在暴露于10⁴铜绿假单胞菌5天后，10个游离皮瓣培养物中有9个没有铜绿假单胞菌生长，而第三阶段对照在所有培养物中均显示有铜绿假单胞菌生长（10个中有8个大量生长）。“生物复合材料”游离皮瓣具有极好的潜力，可为需要重建且细菌污染是重要危险因素的伤口提供形态和结构。
