Carroll C M, Carroll S M, Schuschke D A, Barker J H
Department of Surgery, and the Center for Applied Microcirculatory Research, University of Louisville, KY 40292, USA.
Plast Reconstr Surg. 1998 Aug;102(2):407-15. doi: 10.1097/00006534-199808000-00018.
Distal muscle flap ischemia and necrosis is a recognized complication of acute elevation of large skeletal muscle flaps. The aim of this study was to investigate whether the angiogenic properties of platelet derived growth factor (PDGF) could be used to augment skeletal muscle flap survival through the induction of new blood vessel formation before flap elevation. We compared this form of flap augmentation with that achieved by subjecting the muscle to a bipedicled vascular delay procedure. The animal model used was the latissimus dorsi muscle of the male homozygous (hr/hr) hairless mouse. Four groups of animals were investigated in this study (n = 10 per group). Group 1 was the control group in which the entire muscle was elevated as a thoracodorsally based island flap. In group 2, the muscle was subjected to a bipedicled vascular delay procedure. In group 3, the muscle was treated with 500 microg of recombinant human platelet derived growth factor BB. In group 4, the muscle was treated with placebo. Ten days later the entire latissimus dorsi muscle was elevated as a thoracodorsally based island flap in groups 2, 3, and 4. Percentage muscle flap survival was quantitated in all groups 5 days after elevation of the entire muscle. Angiogenesis was then quantitated by analyzing capillary to muscle fiber ratios after alkaline phosphatase staining of representative latissimus dorsi muscle samples from the proximal, middle, and distal flap segments. Percentage muscle flap survival was significantly better in PDGF treated muscles when compared with the vascularly delayed muscles (p < 0.001). Histologic analysis of latissimus dorsi muscle flaps demonstrated a significantly greater number of capillaries in the middle (p < 0.001) and distal (p < 0.001) flap segments of PDGF-treated flaps when compared with the vascularly delayed flaps. Treatment of skeletal muscle with PDGF before flap creation resulted in survival of the entire muscle flap. Our results suggest that this survival may be secondary to PDGF-induced angiogenesis.
远端肌瓣缺血坏死是大型骨骼肌瓣急性提升术后公认的并发症。本研究的目的是探讨血小板衍生生长因子（PDGF）的血管生成特性是否可用于在肌瓣提升前通过诱导新血管形成来提高骨骼肌瓣的存活率。我们将这种肌瓣增强形式与通过双蒂血管延迟手术处理肌肉所达到的效果进行了比较。所用动物模型为雄性纯合（hr/hr）无毛小鼠的背阔肌。本研究共调查了四组动物（每组n = 10）。第1组为对照组，整块肌肉作为基于胸背血管的岛状肌瓣提升。第2组，肌肉接受双蒂血管延迟手术。第3组，肌肉用500微克重组人血小板衍生生长因子BB处理。第4组，肌肉用安慰剂处理。10天后，第2、3和4组将整块背阔肌作为基于胸背血管的岛状肌瓣提升。在整块肌肉提升5天后，对所有组的肌瓣存活百分比进行定量。然后通过对来自肌瓣近端、中段和远端的代表性背阔肌样本进行碱性磷酸酶染色后分析毛细血管与肌纤维的比例来定量血管生成。与血管延迟的肌瓣相比，PDGF处理的肌瓣的肌瓣存活百分比显著更高（p < 0.001）。背阔肌瓣的组织学分析表明，与血管延迟的肌瓣相比，PDGF处理的肌瓣在中段（p < 0.001）和远端（p < 0.001）肌瓣段的毛细血管数量显著更多。在创建肌瓣前用PDGF处理骨骼肌可使整块肌瓣存活。我们的结果表明，这种存活可能继发于PDGF诱导的血管生成。
