Basic Research for Allograft of Omentum

近年来，利用大网膜瓣进行显微外科重建术取得了显著的进展。但是，在以前用过或切除过的情况下，我们不能使用大网膜皮瓣。因此，同种异体大网膜瓣移植将是一种有用的方法。本文报道了同种异体大网膜的基础研究。首先，最重要的是知道大网膜缺血时间的耐受限度。为此，我们提出了一项实验研究，在这项研究中，我们检查了不同时间止血后的大网膜状况。在成年Wistar大鼠的基础上，以胃网膜血管为基础，抬高大网膜瓣。从1~6h每小时制作一次大网膜缺血模型，以建立缺血时限的标准。10分钟后，大眼和显微镜下观察大网膜皮瓣的情况。分别于开放后10min、1d、2d、3d、7d观察2小时缺血大网膜模型的恢复过程，建立评价大网膜恢复的形态学标准。缺血2小时的大网膜模型在大体和微观上与正常大网膜相似。缺血大网膜时限估计为3~4小时。2小时缺血模型的组织学标本在3天后检查显示血管形成和成纤维细胞的浸润。术后7d观察2小时模型的组织学标本，发现部分胶原纤维重塑。在第二步中，由于同种异体移植使用了免疫抑制剂，所以我们观察了在裸鼠身上使用大网膜皮瓣的伤口愈合情况。正常皮肤上覆盖大网膜的创面基本愈合，无大网膜的创面愈合如疤痕。大网膜皮瓣对裸鼠创面愈合有一定的促进作用。我们的研究是同种异体大网膜移植的第一步。

Microsurgical reconstruction using the omental flap has recently made marked progress. However, we cannot use the omental flap in cases which it was used or resected before. So allograft of the omental flap will be useful. We report the basic research for the allograte of omentum. At first, what is of great importance knows the tolerance limits for omental ischemic time. For this reason, we present an experimental study in which we examined the condition of the omentum after hemostasis of various durations. The omental flaps were elevated based on gastroepiploic vessels in adult Wistar rats. Ischemic omental models were made hourly from 1 to 6 hours in order to establish a standard for ischemic time limit. After 10 minutes, the omental flaps were examined macroscopically as well as microscopically. The recovery process of 2-hour ischemic omental models was examined at 10 minutes, 1 day, 2 days, 3 days, and 7 days after declamping, to establish a morphological standard for the evaluation of omental recovery. Ischemic omental models of 2 hours were similar to normal omentum macroscopically and microscopically. The ischemic omental time limit was estimated to range from 3 to 4 hours. A histological specimen of 2-hour ischemic model examined 3 days after declamping showed vascularization and infiltration of fibroblasts. A histological specimen of 2-hour model examined 7 days after declamping showed remodeled collagen fiber partially. At second step, wound healing using the omental flap in nude mouse was examined, because immunosuppressant is used at allograft. The wound covered with omentum was almost healed in normal skin and the wound without omentum was healed such as a scar. The omental flap was useful for wound healing in nude mouse. Our research was a first step for the allograft of omentum.