A型肉毒毒素对肌皮瓣超量扩张的影响

EFFECT OF BOTULINUM TOXIN TYPE A ON EXCESSIVE EXPANSION OF MYOCUTANEOUS FLAP

目的观察A型肉毒毒素(botulinum toxin type A,BTXA)辅助下肌皮瓣超量扩张的速度及血运情况。方法成年清洁级贵州小型香猪7只,雌雄不限,体重16～20kg。取小型猪左、右侧腰肋部对称区域,随机选取一侧于皮肌层分24点注射2.4mL含96U的BTXA溶液(实验组,n=7),另一侧同法注射等量生理盐水(对照组,n=7)。注射3d后于两侧腰肋部皮肌层下植入200mL扩张器,植入后1周开始注水,每4天注水1次,每次注水使囊内压达到11.97kPa,累计注水达400mL后,对照组和实验组分别维持扩张3周及5周。然后取出扩张器形成扩张肌皮瓣进行原位缝合,同时取肌皮瓣行组织学观察及毛细血管计数。观察两组扩张完成时间及肌皮瓣情况,于扩张器植入后1周、扩张器取出前和扩张肌皮瓣原位缝合术后5d采用红外热像扫描仪观察肌皮瓣血运。结果实验动物均存活至实验完成。实验组扩张完成时间为(54.0±3.1)d,较对照组的(67.0±3.9)d显著提前(t=—8.107,P=0.000)。原位缝合术后肌皮瓣均顺利成活。红外热像扫描仪观察示,除扩张器植入后1周实验组肌皮瓣远端温度高于对照组(P<0.05),原位缝合术后5d实验组中部温度高于对照组(P<0.05)外,其余各时间点两组比较差异均无统计学意义(P>0.05)。组织学观察示,实验组真皮层以及包膜与肌肉层间组织的毛细血管数均高于对照组(P<0.05)。结论肌皮瓣超量扩张时,BTXA可加快肌皮瓣扩张速度,同时改善肌皮瓣血运。

Objective To investigate the effects of botulinum toxin type A（BTXA） on the excessive expansion speed and blood supply of myocutaneous flap.Methods 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 symmertrically 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.Results 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 thermograhy 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）.Conclusion When excessive expansion is performed,BTXA can accelerate the expansion rate and improve the blood supply of expanded myocutaneous flaps