Background/aims To present a case series of patients with facial nerve palsy (FNP) undergoing lower eyelid surgery where inadequate horizontal tarsal length was encountered and managed with a periosteal flap. Methods A two-centre retrospective, non-comparative case series of all patients with FNP who underwent lower eyelid periosteal flap procedures. Theatre records identified all such procedures performed by, or under the supervision of, one of two surgeons (RM, BCP) between November 2018 and November 2020. Outcome measures, including the Cornea, static Asymmetry, Dynamic function, Synkinesis grading score, were measured preoperatively and postoperatively. Results All 17 patients had undergone medial canthal tendon (MCT) plication. Six had previously undergone MCT plication then were listed for further lower eyelid surgery. In 11 cases, horizontal deficiency was encountered intraoperatively, immediately following MCT plication. Four patients were surgery-naïve. 94% were within the ‘contraction phase’ of FNP (ie, greater than 1-year duration); eight (45%) had previously undergone lower eyelid shortening procedures (such as lateral tarsal strip procedure, LTS). All patients had improved lower eyelid position postoperatively, although at 1-year postoperation, four patients require redo lower eyelid surgery. Conclusions MCT plication and stabilisation appear to be closely linked to the need for lower eyelid lengthening procedures, particularly in patients who have also undergone LTS and/or those within the ‘contraction phase’ of FNP. Unnecessary loss of horizontal tarsal length (particularly during LTS procedures) must be avoided in patients with FNP. Surgeons managing such patients should take care to identify inadvertent eyelid shortening early and be prepared to perform a lateral periosteal flap when required. Data are available upon reasonable request. N/A.

中文翻译：

---

面神经麻痹下眼睑延长：什么时候需要骨膜瓣？

背景/目的 介绍一系列接受下眼睑手术的面神经麻痹 (FNP) 患者，其中遇到水平睑板长度不足的情况，并通过骨膜瓣进行处理。方法 对所有接受下眼睑骨膜瓣手术的 FNP 患者进行两中心回顾性、非比较性病例系列研究。手术室记录确定了 2018 年 11 月至 2020 年 11 月期间由两名外科医生（RM、BCP）之一执行或监督的所有此类手术。测量了结果指标，包括角膜、静态不对称性、动态功能、联动力分级评分术前和术后。结果 17例患者均行内眦肌腱（MCT）折叠术。六人之前曾接受过 MCT 折叠术，然后被列入进一步下眼睑手术的名单。11 例患者在术中、MCT 折叠后立即出现水平缺陷。四名患者未曾接受过手术。94% 处于 FNP 的“收缩阶段”（即持续时间超过 1 年）；八名 (45%) 之前曾接受过下眼睑缩短手术（例如外侧睑板剥离手术，LTS）。所有患者术后下眼睑位置均得到改善，尽管术后 1 年有 4 名患者需要重做下眼睑手术。结论 MCT 折叠和稳定似乎与下眼睑延长手术的需要密切相关，特别是对于也接受过 LTS 的患者和/或处于 FNP“收缩期”的患者。FNP 患者必须避免不必要的水平跗骨长度损失（特别是在 LTS 手术期间）。治疗此类患者的外科医生应注意及早发现无意的眼睑缩短，并准备在需要时进行侧骨膜瓣修复。数据可根据合理要求提供。不适用。