The Royal Free NHS Foundation Trust, Pond Street, London, NW3 2QG, UK; Division of Surgery and Interventional Science, University College London, Gower Street, London, WC1E 7HB, UK; University of Rochester Medical Center, 601 Elmwood Avenue Box 661, Rochester, NY, USA.
University of Rochester Medical Center, 601 Elmwood Avenue Box 661, Rochester, NY, USA.
Ann Anat. 2019 May;223:127-135. doi: 10.1016/j.aanat.2019.03.001. Epub 2019 Mar 22.
Animal models for the study of facial paralysis have been well developed, but concern has arisen regarding the accuracy of eye closure and whisker movement as outcome measures due to new data regarding interconnectivity between facial nerve branches and autonomic innervation. The posterior auricular nerve (PAN) is an isolated branch of the facial nerve which has been confirmed as the sole motor innervat or of the interscutularis muscle. This study was designed to develop a model for facial nerve palsy utilizing the PAN and interscutularis muscle.
A custom-made automated video capture system was built into a poly methyl methacrylate cage using a high definition monochrome digital camera and image sensor to record the animal as it drank from a water feeder. A copper floor pad and copper collar around the water feeder were connected to an electrical circuit for automatic saving of the video recording 10 s prior to and 30 s following the drinking event. A pre-operative baseline recording of ear movement during drinking was captured. Female YFP-16 mice at 6 weeks were assigned to sham (Sh, n = 5), nerve excision (Ex, n = 10), or nerve crush (Cr, n = 10) groups with all interventions performed on the right PAN. Sh mice were irrigated with 10 ml normal saline as were the Ex and Cr mice following operative intervention. In Ex mice, a 3 mm section of the PAN was sharply excised and nerve gap was confirmed with fluorescent microscopy. In Cr mice, the PAN was crushed 3 mm from the origin of the facial nerve trunk with size 5 jeweler's forceps for two periods of 20 s. Post-operative video recordings were collected on post-operative days (POD) 1, 10, 20, and 30. To determine the change in ear movement, the right ear was graphically compared to the left control side.
Sh animals exhibited a statistically significant reduction in ear movement at POD01 compared to other POD recordings (p < 0.05), but no significant change in right ear movement following POD05. Ex animals had a significant reduction in right ear movement at all PODs in comparison to the left ear (p < 0.05) with no significant change in right ear movement during the study period (p = 0.94). Cr animals showed a significant reduction in right ear movement compared to the left at POD01, POD10, and POD20 (p < 0.05). At POD30, there was no significant difference between ear movement on either side (p = 0.35). There was a significant change in right ear movement during the data collection period (p < 0.05).
The results show that significant differences were demonstrated between the experimental groups and that significant changes within the crush group were identifiable making this an acceptable model to develop as an accurate outcome measure following rodent facial nerve surgery.
用于研究面瘫的动物模型已经得到了很好的发展，但由于面神经分支与自主神经支配之间新的数据，对面部闭合和胡须运动等作为结果测量的准确性产生了担忧。耳后神经（PAN）是面神经的一个孤立分支，已被证实是皮肌唯一的运动神经支配。本研究旨在利用 PAN 和皮肌建立面神经瘫痪模型。
使用高清晰度单色数字相机和图像传感器，在聚甲基丙烯酸甲酯笼中构建了一个定制的自动化视频捕捉系统，以记录动物从水喂养器饮水的情况。铜地板垫和水喂养器周围的铜领与电路相连，用于在饮水事件前自动保存 10 秒和后 30 秒的视频记录。在术前捕获了耳部在饮水过程中的运动的基线记录。6 周龄的 YFP-16 雌性小鼠被分配到假手术（Sh，n=5）、神经切除（Ex，n=10）或神经挤压（Cr，n=10）组，所有干预均在右侧 PAN 上进行。Sh 组的小鼠用 10ml 生理盐水冲洗，与 Ex 和 Cr 组在手术后干预后冲洗。在 Ex 组中，用锋利的手术刀切除 3mm 节段的 PAN，并通过荧光显微镜确认神经间隙。在 Cr 组中，用 5 号珠宝商镊子将 PAN 在面神经干起源处挤压 3mm 长，持续 20s 两个周期。在术后第 1、10、20 和 30 天收集术后视频记录。为了确定耳朵运动的变化，将右耳与左侧对照侧进行图形比较。
Sh 动物在术后第 1 天与其他术后记录相比，耳部运动有统计学显著减少（p<0.05），但术后第 5 天右耳运动无显著变化。Ex 动物在所有 POD 与左耳相比，右耳运动均有显著减少（p<0.05），但在研究期间右耳运动无显著变化（p=0.94）。Cr 动物在术后第 1、10 和 20 天与左耳相比，右耳运动明显减少（p<0.05）。在术后第 30 天，两侧耳部运动无显著差异（p=0.35）。在数据收集期间，右耳运动有显著变化（p<0.05）。
结果表明，实验组之间存在显著差异，并且在挤压组内发生了显著变化，这使得该模型成为一种可接受的、准确的啮齿动物面神经手术后的结果测量方法。
