Jeong Woonhyeok, Oh Daemyung, Kwon Sunyoung, Kim Jinhee, Son Daegu
Department of Plastic and Reconstructive Surgery, Institute for Medical Science, Keimyung University School of Medicine, Daegu, South Korea.
Department of Pathology, Keimyung University School of Medicine, Daegu, South Korea.
J Tissue Viability. 2016 Nov;25(4):237-243. doi: 10.1016/j.jtv.2016.06.004. Epub 2016 Jun 16.
A chronic wound or non-healing wound is one that fails to heal for at least 30 days after injury. This study was designed to create delayed wound healing induced by irradiation and mechanical compression using silicone block. Two female pigs received a single fraction of 20 Gy with 6-MeV electrons to a 22 × 60 cm field on the dorsal body skin 7 weeks before experimentation. A 30 × 30 mm sized wounds were created with preservation of muscle fascia on the dorsum. In groups of six, wounds were designated to be control (C) or test areas of irradiation only (T0), irradiation with silicone blocks for 1 week (T1), irradiation with silicone blocks for 2 weeks (T2), and irradiation with silicone blocks for 3 weeks (T3). Wound contraction, bacterial culture, and histological analysis were performed at 1-week intervals for 4 weeks. Control wounds displayed complete re-epithelialization at Weeks 4; however, all experimental groups (T0, T1, T2, and T3 groups) showed necrosis and delayed healing at Week 4. The number of bacterial strains in control wounds differed significantly from values recorded for all experimental groups from Weeks 1-3 (p < 0.05). However, in comparing the various test wounds (T0, T1, T2, and T3 groups), the numbers of strains did not differ significantly from Weeks 1-4. In the histological analysis, the control wound showed a peak influx of acute and chronic inflammatory cell and diminished inflammation thereafter. However, all experimental groups showed no peak in inflammatory score and prolonged chronic inflammation. In conclusion, radiation exposure alone, which triggers intense inflammation and extensive recruitment of inflammatory cells, proved sufficient to prevent re-epithelialization of skin at 30 days. Insertion of silicone blocks had limited effects on promoting delayed wound healing. Consequently, we now recommend using irradiation alone to simulate delayed wound healing in an experimental setting.
慢性伤口或难愈合伤口是指受伤后至少30天仍未愈合的伤口。本研究旨在利用硅胶块制造由辐射和机械压迫诱导的延迟伤口愈合。在实验前7周，两只雌性猪接受了单次20 Gy的6 MeV电子照射，照射野为背部皮肤22×60 cm。在背部制造30×30 mm大小的伤口，保留肌肉筋膜。将伤口分为六组，分别为对照组（C）、仅照射的测试组（T0）、用硅胶块照射1周的组（T1）、用硅胶块照射2周的组（T2）和用硅胶块照射3周的组（T3）。在4周内每隔1周进行伤口收缩、细菌培养和组织学分析。对照组伤口在第4周显示完全重新上皮化；然而，所有实验组（T0、T1、T2和T3组）在第4周均出现坏死和延迟愈合。对照组伤口中的细菌菌株数量与第1 - 3周所有实验组记录的值有显著差异（p < 0.05）。然而，在比较各种测试伤口（T0、T1、T2和T3组）时，第1 - 4周菌株数量没有显著差异。在组织学分析中，对照组伤口显示急性和慢性炎症细胞大量涌入并随后炎症减轻。然而，所有实验组均未出现炎症评分峰值且慢性炎症持续时间延长。总之，单独的辐射暴露会引发强烈炎症和炎症细胞的大量募集，足以在30天时阻止皮肤重新上皮化。插入硅胶块对促进延迟伤口愈合的作用有限。因此，我们现在建议在实验环境中单独使用辐射来模拟延迟伤口愈合。
