摘要
目的明确 SMAS 与面神经的关系。方法对12具(24侧)成人尸头行大体解剖观察。结果 SMAS 分布于面中部,向前逐渐变薄,于口角水平外侧有小范围的“洞区”。面神经出腮腺后,并非在 SMAS 深面,而是在咬肌筋膜深面走行。面神经额支在颧弓以下0.5cm 区域穿出深筋膜,跨过颧弓。在颊脂肪垫区,大部分面神经分支走行在垫内,小部分分支形成面神经丛,分布于其表面。在颧大肌表面上1/3恒定有一颧支跨过,支配眼轮匝肌下外侧9例(占37.5%);颧大、小肌及眼轮匝肌8例(占33.3%);颧大、小肌7例(占29.2%)。结论面部多层次剥离除皱术应在颧弓以下0.5cm 区域行 SMAS 下剥离,至面中部时,应注意保护颧大肌表面上1/3段的面神经颧支,只在颧大肌中下2/3段区域进行剥离,向内掀起颧脂肪垫;或通过下睑缘皮肤切口,向下掀起眼轮匝肌(注意保护位于颧大肌上1/3段的面神经颧支),与经耳前 SMAS 下剥离腔隙连通,如上操作可避免面神经损伤。
Objective To investigate the relationship between the SMAS and the facial nerve divi- sions in the cheek area.Method We dissected 12 cadaver heads(24 sides).Results①SMAS distribut- ed over the middle face.It became thinner as it extended forward and there was a small aperture lateral to the mouth.The branches of facial nerve lay directly beneath the parotidomassetric fascia after emerging from the parotid gland.②The frontal branch penetrated the deep fascia to the SMAS at about 0.5cm be- low the zygomatic arch.③Some buccal branches went through the cheek fat pad while the others lay on its surface directly under the thin SMAS.④There was constantly a zygomatic ramus went into the upper one third of the zygomaticus.It innervated the lower and lateral orbicularis oculi muscle in 9 of 24 sides (37.5%)of the cadaver heads,zygomaticus major and minor and orbicularis oculi muscle in 8 of 24 sides (33.3%),and the zygomaticus major and minor in 7 of 24 sides(29.2%).Conclusion During facelift- ing,wide dissection of the SMAS should be done directly above the parotidomassetric fascia and 0.5 cm below the zygomatic arch.While approaching the middle face,the dissection should be limited to the low- er two third of the zygomaticus,followed by elevating the zygomatic fat.The authors dissect the nasolabial fold through the lower eyelid incision,then the dissection should go downwards,under the orbicularis o- cull muscle,to the nasolabial area.In a clinical situation,care must be taken not to damage the facial nerve trunk,and dissection of the upper one third of the zygomaticus should be avoided.
