ANATOMICAL REASONS FOR PROBLEMS AFTER NEURECTOMY FOR BLEPHAROSPASM: A STUDY IN CADAVERS

The purpose of this study is to clarify the mechanisms of the problems that develop after neurectomy for blepharospasm. The left facial nerves in 10 Japanese cadavers were dissected under a surgical microscope. The temporal, zygomatic, and buccal branches innervated to the orbicularis oculi muscle. These three groups formed a well-communicating plexus posterior to the orbicularis. The most inferior buccal branch curved in the deep layer in the lower part of the cheek. In the cheek, both the buccal and the temporal branches had ramifications of other facial muscles. The information given in previous anatomical textbooks did not specifically define the denervation of the orbicularis. When neurectomy was done in the past, the inferior buccal branch may have been kept intact, or other facial muscles as well as the orbicularis may have been denervated which caused the blepharospasm to recur and complications to develop after neurectomy.     

Selective facial neurectomy for spastic disorders of the facial nerve

Selective facial neurectomy in combination with bilateral musculocutaneous resection, plication brow lift, upper lid blepharoplasty, and limited rhytidectomy was performed on 18 patients with essential blepharospasm, eight with hemifacial spasm, and two with CNS vascular compression malformations. Microscopy showed the nerve tissues to be normal. Initial results were excellent. At 3 months there was a slight, persistent spastic twitching of the affected muscles in five nerves (a 14% failure rate in correcting blepharospasm). After 13 months there were four additional failures resulting from nerve regrowth in three and from one patient not completing therapy. The overall blepharospasm failure rate was 26%. On repeat neurectomy those with nerve regrowth presented with a diffuse, fine meshwork of nerve fibers reinnervating the mimetic facial musculature. In six of seven patients operated on again, spasticity was eliminated. The initial surgical failure rate has been corrected by resecting the frontal branch and the superior division of the buccal branch of the facial nerve. Only repeat neurectomy can correct long-term failures resulting from facial nerve regrowth.     

Angular nerve: new insights on innervation of the corrugator supercilii and procerus muscles.

BACKGROUND: Elimination of glabellar frown lines by direct denervation of the corrugator and procerus muscles has proven elusive. Furrows often persist after the frontal branch of the facial nerve has been divided. In order to find an explanation for these observations and to provide an anatomic basis for future surgical strategies, the pattern of innervation of these muscles was studied. METHODS: Two separate investigations were performed: (1) cadaveric anatomical dissection in 18 fresh cadaver hemi-faces utilizing loupe magnification, operating microscope, and template tracings; and (2) electrophysiologic testing performed in 12 healthy volunteers utilizing a Viking Ile nerve stimulator (Nicolet, Madison, WI). RESULTS: The corrugator was found to have a dual nerve supply with contributions from branches of the frontal, zygomatic and buccal branches of the facial nerve. The frontal branch passes deep to the orbicularis at the level of the eyebrow; and the buccal branch, after receiving a contribution from the zygomatic, forms the angular nerve, which then passes superiorly in front of the medial canthus to supply both corrugator and procerus. The procerus muscle was found to receive contributions from the angular nerve exclusively. CONCLUSIONS: Procedures designed to denervate the corrugator should be directed at both components of its redundant nerve supply, the frontal branch as well as the angular nerve. Division of the angular nerve will also denervate the procerus muscle. Both frontal nerve branches and angular nerve components are accessible through an upper blepharoplasty incision.     

现代面部除皱术的面神经解剖学研究

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。     

现代面中除皱术的面神经解剖学研究

目的 明确ＳＭＡＳ与面神经的关系。方法 对１２具（２４例）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,于口角水平外侧水小范围的“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     

面神经颊支和下颌缘支的解剖学研究及应用

目的 观察面神经颊支与下颌缘支肌外、肌内走行分布情况，为面瘫整复术中受区神经的选择和预防神经支损伤提供依据。方法 在24侧头部标本中，分别观测颊支和下颌缘支的分支数目、吻合情况、走行中的层次、颊支与腮腺导管以及下颌缘支与下颌骨下缘、面血管的关系，结合Sihler’s肌内神经染色，明确其支配肌肉和在肌内的分布规律；并在40例面瘫手术患者受区面神经分支的寻找和选择中进行验证。结果 腮腺导管体表投影较恒定，面神经颊支以2～3支为主，占87．5％，多数分布在导管上方10．7mm和下方9．3mm的范围内，支配中面部表情肌。下颌缘支以1～2支为主，占95．9％，多数分布在下颌骨下缘上方13．4mm和下方4．8mm的范围内，跨面动脉浅面，支配下唇诸肌。结论 面神经颊支与腮腺导管、下颌缘支与面动脉及下颌骨下缘有着紧密的关系。应用改良Sihler法，可以更为清晰的显示人面部表情肌的肌内神经分布情况。     

面神经分支在颞区的显微解剖学研究

目的 明确面神经在颞区的分布层次和范围，指导面部年轻化手术的操作入路。方法 12具(24侧)成人尸头标本，于5倍光学显微镜下行颞区的解剖观察。结果 颞区包含面神经的颞支和颧支：由面神经的上支分出，出腮腺上缘，颞支发出3～8个分支、颧支2～4个分支，行于颞浅筋膜深面。颞支越过颧弓至颞区，分布于额肌、眼轮匝肌、皱眉肌和耳周围肌等组织，主导其运动；颧支由腮腺上缘向前上方越过颧弓至外眦，支配眼轮匝肌和颧肌的运动；两支之间以及与眼神经的眶上神经和泪腺神经之间．都有交通支。结论 面神经的颞支和颧支分布在颞浅筋膜的深面和颞深筋膜的浅层之间的组织内，支配额部、眼周和耳部的表情肌运动；面部年轻化手术在分离颞区时．应避免在此层进行。     

Superselective neurectomy with periorbital primary reconstruction for blepharospasm. Case report.

A 66-year old man with blepharospasm and ptosis of the brow was treated with a combined procedure in which the branches of the facial nerve were excised at the margin of the orbicularis, and the periorbital area was reconstructed simultaneously. The condition improved after the treatment with no occurrence of either oral complications or facial anaesthesia.     

Split thoracodorsal nerve funicular graft combined with functional latissimus dorsi musculocutaneous flap transfer for immediate facial reanimation after tumor ablation

The authors report a case of immediate facial reanimation resulting from functional latissimus dorsi musculocutaneous flap transfer and funicular grafting of the thoracodorsal nerve after cheek tumor ablation. After wide excision of the tumor, including the facial nerve except the temporal branch and part of the zygomatic major muscle and masseter muscle, the authors reconstructed the cheek skin and provided movement by performing a small-segment latissimus dorsi musculocutaneous flap transfer using Harii's method and the defect of the buccal and marginal mandibular branches of the facial nerve by funicular grafting from one of the two funicles of the thoracodorsal nerve. After 6 months, the transplanted, small-segment latissimus dorsi muscle showed good voluntary movement, and the lower orbiculus oris and depressor oris presented good functional recovery. The authors believe the two funicles of the thoracodorsal nerve can be used independently for two purposes: one for functional segmental muscle transfer and the other for nerve grafting to defects of branches of the facial nerve. This concept makes it possible to reconstruct multiple facial movements while minimizing donor site morbidity by means of immediate facial reanimation.     

SUPERSELECTIVE NEURECTOMY WITH PERIORBITAL PRIMARY RECONSTRUCTION FOR BLEPHAROSPASM: Case report

A 66-year old man with blepharospasm and ptosis of the brow was treated with a combined procedure in which the branches of the facial nerve were excised at the margin of the orbicularis, and the periorbital area was reconstructed simultaneously. The condition improved after the treatment with no occurrence of either oral complications or facial anaesthesia.     

面神经在眶周区的解剖研究

目的探讨面神经颠支、颧支的终末分支进入眼轮匝肌位置和体表解剖。方法选择6具新鲜尸体标本。观察解剖面神经颠支、颧支，辨别出进入眼轮匝肌的颠支、颧支与外眦的关系。通过外眦做一垂线和水平线，使之分别与矢状面和冠状面平行。通过外眦的垂线和水平线来确定进入眼轮匝肌的神经分支与外眦的解剖关系。结果颠支进入眼轮匝肌时．位于外眦水平线平均为2．64cm，位于外眦垂线外平均为2．40cm。在眼轮匝肌的侧缘、颞支和颧支的垂直距离平均为1.54cm。结论位于面神经走行的上或下、与其平行的切口，不易损伤面神经分支。     

Efficacy of the "baby-sitter" procedure after prolonged denervation

This study was undertaken to evaluate whether 40 percent of the hypoglossal nerve, which showed optimal efficacy in restoring orbicularis oculi muscle (OOM) function after different percentages of partial neurectomy in a previous study would be effective after prolonged denervation time. Twenty Sprague-Dawley rats were divided into four groups. In first-stage surgery the left facial nerve of all animals was transected at the level of the stylomastoid foramen and main zygomatic branch. Group A (controls) consisted of animals with only left facial nerves transected (no repair). In Groups B, C, and D the facial nerve was transected and the facial musculature was denervated for a period of 4, 8, and 12 weeks respectively. During a second-stage procedure, a 40 percent neurectomy was performed on the hypoglossal nerve. Subsequently, a nerve transfer was performed by coaptations of a saphenous nerve graft to the neurectomized hypoglossal nerve and the main zygomatic branch of the facial nerve that innervated the OOM. Behavioral analysis of blink reflex, electrophysiology, and axon and motor end-plate counts in Groups B, C, and D showed superior results compared to Group A. There was no statistically significant difference observed among Groups B, C, and D (p > 0.05). Despite the diminished number of axons in the zygomatic branch and motor end-plates in the orbicularis oculi muscle after 12 weeks of denervation, there was still sufficient muscle target recovery to effect some eye closure in all groups except the controls. This study demonstrated in this model that the 40 percent partial neurectomy of the XII to VII component of the "baby-sitter" procedure was effective even after prolonged denervation.     

Paralysis of the lower lip and the selective neurectomy

Summary To restore facial symmetry in cases of paralyzed lower lip, we have followed the selective neurectomy procedure developed for the lower lip, by Marino [7] and Marino and Alurralde [8]. After cadaveric dissections carried out on 10 facial halves, we demonstrated that several other interconnected branches of the facial nerve innervate the lower lip musculature. This fact led us not to limit the operation to the sectioning of the proximal marginalis mandibularis, but to include in the neurectomy these peripheral branches also. As a result of the more extensive resection of motor nerves the return of movement to the denervated muscles can be avoided.     

Arterial anatomy of the lower lip.

The arterial anatomy of the lower lip was investigated in 12 sides of six fresh cadavers that had been injected systemically with a lead oxide and gelatin mixture. We found that the blood supply of the lower lip was derived from the facial artery and three dominant labial arteries: the inferior labial artery, the horizontal labiomental artery, and the vertical labiomental artery. The inferior labial artery was derived from the facial artery or superior labial artery, and ran through the submucous tissue horizontally. The horizontal labiomental artery arising from the facial artery was located between the depressor labii inferioris muscle and orbicularis oris muscle. The vertical labiomental artery arose from the submental artery. These three arteries provided small vessels that traversed vertically. These small vessels and the small branches of the facial artery, that run superficial and deep to the orbicularis oris muscle, formed a vascular network in subcutaneous and submucous tissues and minute vessels branched off to the skin, mucosa, and muscles.     

Subfascial and submuscular methods of temporal muscle dissection and their relationship to the frontal branch of the facial nerve. Technical note

The microsurgical anatomy of the temporal and zygomatic branches of the facial nerve are presented along with related local vasculature (frontal and parietal branches of the superficial temporal artery [STA]) as encountered when using subfascial and submuscular temporal muscle dissection techniques for anterolateral craniotomies. Twenty sides were studied in 10 cadaveric specimens that had been previously injected with latex. The rami of the temporal and zygomatic branches of the facial nerve and branches of the STA were dissected out through pterional and orbitozygomatic approaches by using a submuscular or subfascial temporal muscle dissection technique. The three rami of the temporal branch of the facial nerve (the auricularis, frontalis, and orbicularis) were found to run within the galeal plane of the scalp. The zygomatic branch of the facial nerve was found to course deeper than the most caudal extension of the galea, known as the superficial musculoaponeurotic layer. The frontal branch of the STA served as an important landmark for the subfascial or submuscular dissections because excessive reflection of the scalp flap inferior to the level of this vessel would inadvertently injure the frontalis branch of the facial nerve. Subfascial and submuscular dissections of the temporal muscle offer an alternative to the interfascial technique during anterolateral craniotomies. Scalp and temporal dissection performed with careful attention to anatomical landmarks (frontal branch of the STA and the suprafascial fat pad) provides a safe and expeditious alternative to the traditional interfascial technique.     

Static syndrome after cross-facial nerve transplantation

A cross-facial nerve graft connected to buccal branches of the healthy facial nerve may carry axons destined for the orbicularis oris muscle as well as axons destined for elevators and abductors of the corner of the mouth. If this nerve graft innervates a pedicled or free muscle flap, contractions of the flap or part of it will also occur when the patient purses his lips. This results in immobilization of the corner of the mouth. On the other hand, smiling may lead to simultaneous contraction of other erroneously reinnervated muscle fibers, equally immobilizing the corner of the mouth. Electromyography in these cases shows well-reinnervated musculature. The only solution to prevent this so-called static syndrome is to transplant smaller nerves connected at more peripheral levels to smaller facial nerve branches with more specific functions.     

颊肌黏膜瓣在宽大红唇及口轮匝肌缺损修复中的应用

目的探讨修复大面积的红唇及口轮匝肌缺损的手术方法。方法设计以面动脉前颊支为血管蒂的颊肌黏膜瓣,用以修复上或下唇宽大的红唇及口轮匝肌缺损。结果共治疗7例,5例患者术后无任何并发症,2例患者颊肌黏膜瓣尖端黏膜坏死,未累及肌层,术后创面通过黏膜上皮化而愈合,无其他并发症发生。术后早期即可测到温度觉、触觉,肌电图和电镜显示瓣内肌肉有运动神经支配。结论应用颊肌黏膜瓣可以修复用常规方法难以解决的宽大红唇及口轮匝肌缺损,并且可获得良好的形态、感觉和功能。     

Primary one-stage reconstruction of cheek defect after a shotgun blast to the face: use of the latissimus dorsi musculocutaneous free flap for soft-tissue repair and facial reanimation

The authors describe a case of a shotgun blast injury to the face in which early definitive repair of both facial soft tissues and facial reanimation was accomplished in one stage using a free flap. The trauma occurred 2 days before presentation via a hunting rifle fired at a short range. On examination, a 8 x 5-cm cheek defect was evident, involving the full thickness of the perioral facial mimetic muscles as well. A free latissimus dorsi musculocutaneous flap was transferred to the defect, with the thoracodorsal nerve coapted to an ipsilateral, severed buccal branch of the facial nerve. Postoperatively, the flap survived completely, with its skin paddle excised subsequently in two stages. Good muscle movement was obtained, providing resting symmetry and a pleasant smile. Other than soft-tissue and bony defects resulting from shotgun injuries, ablation of the facial nerve or facial mimetic muscles may be an important component of the defect that needs further consideration. The authors conclude that the current technique of one-stage, early definitive repair of soft tissues and facial reanimation in such cases of facial shotgun blast injury offers the advantages of achieving both goals with one flap and accomplishing the procedure primarily in one stage.     

Anatomic organization of the cat facial nerve

The location of efferent neurons supplying muscles innervated by the facial nerve was studied in the brain stem of the cat; horseradish peroxidase (HRP) was used as a tracer of retrograde protein transport. One to 15 microliters of HRP was injected into various muscles. Orbicularis oculi and orbicularis oris muscles were represented in the lateral division of the facial nucleus. The platysma, posterior belly of digastric, auricularis superior, and frontalis muscles were represented in the medial division of the facial nucleus. No labeled neuron was found in the trigeminal nerve nucleus or any other brain stem nuclei. The grouping of the motor neurons into relatively discrete areas of the nucleus and the fact that the facial nerve innervates various muscles through separate branches suggest that these motor neurons travel together in discrete groups within the facial nerve trunk. However, orientation of the facial nerve fibers was demonstrated by use of the Marchi method and an osmium stain after complete and partial transection of the nerve at the internal auditory meatus; this showed that the motor axons to the peripheral branches are diffusely located throughout the temporal course of the facial nerve.     

采用多重标记物示踪化学去细胞异体神经修复大鼠面神经缺损

[目的]探索用荧光金、量子点、固蓝"三标"逆行示踪方法来评价化学去细胞异体神经移植修复大鼠面神经缺损后颊支、下颌缘支、颈支的再生及神经的物质运输功能。[方法]外科显微镜下解剖、分离出鼠的左侧颅外段面神经主干及各分支(颞支、颧支、颊支、下颌缘支、颈支),在出茎乳孔处离断面神经主干,分别在距该断点10 mm处离断5个分支,移植化学去细胞异体全面神经,术后2个月暴露面神经,在颊支、下颌缘支、颈支吻合口远端分别注射荧光金、量子点、固蓝,3 d后脑干取材,冰冻切片,并在荧光显微镜下观察脑干内3种示踪剂的分布情况。[结果]将发源于脑干的面神经核团进行冰冻切片,荧光显微镜下观察到被荧光金、量子点、固蓝标记的神经元分别显示出黄色、红色和蓝色。[结论]根据神经轴浆运输的原理,采用多种标记物示踪法评价异体神经移植修复面神经损伤后神经干及各分支连续性的恢复情况,操作简便,可靠易行,是一种理想的评价方法。