Borodic G E, Cozzolino D, Ferrante R, Wiegner A W, Young R R
Department of Ophthalmology, Massachusetts General Hospital, Boston 02114.
Ophthalmic Plast Reconstr Surg. 1991;7(1):54-60. doi: 10.1097/00002341-199103000-00007.
Motor points (areas of maximal sensitivity to electrical stimulation) were found in constant locations over orbicularis oculi when measured in both eyes of six normal subjects. All subjects had a motor point at the lateral terminus of the upper lid crease and the medial extent of the lower lid crease. A study of the innervation zone [distribution of neuromuscular junctions (NMJ)] was conducted on strips of pretarsal and preseptal portions of the upper eyelid orbicularis that had been removed routinely during involutional ptosis surgery. There was no significant difference in NMJ concentration between the medial and lateral sections, as determined by cholinesterase staining. Therefore, we concluded that the innervation zone is diffuse for the orbicularis muscle within this portion of the upper eyelid. Single-point injections of botulinum toxin were then compared to the conventional multiple injection sites on separate eyes in 10 patients with benign essential blepharospasm. Eight of the 10 patients reported greater relief on the side given injections into multiple points; the other two patients experienced no difference between the two methods. Both histologic data and clinical observation of response to botulinum toxin injection suggest the innervation zone for the upper orbicularis is diffuse. Thus, we conclude that multiple injections are superior to the injection of a single motor point.
在对6名正常受试者的双眼进行测量时，发现眼轮匝肌的运动点（对电刺激敏感度最高的区域）位于恒定位置。所有受试者在上睑皱襞外侧末端和下睑皱襞内侧范围均有一个运动点。对在眼睑皮肤松弛症手术中常规切除的上睑眼轮匝肌睑板前和眶隔前部分的条带进行了神经支配区[神经肌肉接头（NMJ）分布]研究。通过胆碱酯酶染色测定，内侧和外侧部分的NMJ浓度无显著差异。因此，我们得出结论，上睑这部分眼轮匝肌的神经支配区是弥散的。然后，在10例良性特发性眼睑痉挛患者的不同眼睛上，将肉毒杆菌毒素单点注射与传统的多点注射部位进行了比较。10例患者中有8例报告多点注射侧的缓解效果更好；另外2例患者在两种方法之间没有差异。肉毒杆菌毒素注射的组织学数据和临床反应观察均表明，上睑眼轮匝肌的神经支配区是弥散的。因此，我们得出结论，多点注射优于单点运动点注射。
