Duan Chenwang, Xu Gang, Zhou Jianhong, Wei Gangqiang, Li Senkai
Department of Burn and Plastic Surgery, Tangshan Gongren Hospital, Tangshan Hebei 063000, PR China
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2011 Sep;25(9):1063-6.
To investigate the effects of botulinum toxin type A (BTXA) on the excessive expansion speed and blood supply of myocutaneous flap.
Seven adult Guizhou minipigs of clean grade were included, female or male and weighing 16-20 kg. The 2.4 mL BTXA solution (96 U) was injected in cutaneous muscle (24 points) of one side as experimental group (n = 7), the 2.4 mL saline in the other side as control group (n = 7). Two expanders (200 mL) were implanted beneath the cutaneous muscle on the bilateral flank of each pig symmetrically at 3 days after injection. One week later, the expanders were filled with saline every 4 days with an intracapsular pressure of 11.97 kPa, and accumulative total amounted to 400 mL for 3 weeks in control group and 5 weeks in experimental group. Then the expanders were taken out; the myocutaneous flaps formed and were sutured in situ. The myocutaneous flaps were cut for histological examination and capillary count. The expansion speed of the myocutaneous flap were recorded. The blood supply of the myocutaneous flap were observed by infrared thermography at 1 week after implantation expanders, before removing the expanders, and at 5 days after myocutaneous flap suture in situ.
All the animals survived to the end of the experiment. The total expansion time was (54.0 +/- 3.1) days in experimental group and (67.0 +/- 3.9) days in control group, showing significant difference (t = -8.107, P = 0.000). All myocutaneous flaps survived after being sutured in situ. Infrared thermograph revealed that the temperature of the distal myocutaneous flap in experimental group was significantly higher than that in control group at 1 week after implantation of expanders (P < 0.05); at 5 days after myocutaneous flap suture in situ, the temperature of the central flap in experimental group was significantly higher than that in control group (P < 0.05); and there was no significant difference between 2 groups at the other time points (P > 0.05). The histological observation showed that the blood vessel density of the dermal layer and tissue between the capsule and the muscle layer in experimental group was significantly higher than those in control group (P < 0.05).
When excessive expansion is performed, BTXA can accelerate the expansion rate and improve the blood supply of expanded myocutaneous flaps.
探讨A型肉毒毒素（BTXA）对肌皮瓣过度扩张速度及血供的影响。
纳入7只清洁级成年贵州小型猪，雌雄不限，体重16 - 20 kg。将2.4 mL BTXA溶液（96 U）注射于一侧的皮肤肌肉（24个点）作为实验组（n = 7），另一侧注射2.4 mL生理盐水作为对照组（n = 7）。注射后3天，在每只猪双侧胁腹的皮肤肌肉下对称植入两个扩张器（200 mL）。1周后，对照组每4天向扩张器内注入生理盐水，囊内压力为11.97 kPa，3周累计注入总量达400 mL，实验组为5周。然后取出扩张器；形成肌皮瓣并原位缝合。切取肌皮瓣进行组织学检查及毛细血管计数。记录肌皮瓣的扩张速度。在植入扩张器后1周、取出扩张器前以及肌皮瓣原位缝合后5天，通过红外热成像观察肌皮瓣的血供情况。
所有动物均存活至实验结束。实验组总扩张时间为（54.0±3.1）天，对照组为（67.0±3.9）天，差异有统计学意义（t = -8.107，P = 0.000）。所有肌皮瓣原位缝合后均存活。红外热成像显示，植入扩张器后1周，实验组肌皮瓣远端温度显著高于对照组（P < 0.05）；肌皮瓣原位缝合后5天，实验组皮瓣中央温度显著高于对照组（P < 0.05）；其他时间点两组间差异无统计学意义（P > 0.05）。组织学观察显示，实验组真皮层及囊与肌层之间组织的血管密度显著高于对照组（P < 0.05）。
在进行过度扩张时，BTXA可加快扩张速度并改善扩张后肌皮瓣的血供。
