中耳膽脂瘤手術使用持續面神經監測的經驗報告

Experience of Intraoperative Facial Nerve Monitoring in Middle Ear Cholesteatoma Surgery

鄭仁信(Jen-Hsin Cheng) ； 楊昭輝(Chao-Hui Yang) ； 黃仲鋒(Chung-Feng Hwang)

《台灣耳鼻喉頭頸外科雜誌》 51卷4期 (2016/12) Pp. 219-227

https://doi.org/10.6286/2016.51.4.219

摘要

背景：由於膽脂瘤本身具有侵犯性及位於特殊解剖位置，在疾病自然進程及手術中有可能損及顏面神經並產生麻痺。除此之外，顏面神經管裂隙的存在也增加神經受損的機會。常規使用顏面神經監控，可幫忙辨別神經位置及裂隙並預防醫源性損傷。本研究提供膽脂瘤術中使用顏面神經監測的經驗，並探討顏面神經裂隙在耳科手術中之發生率。方法：回溯病歷總共62次膽脂瘤手術，使用面神經監測儀，術中使用單極刺激器偵測顏面神經裂隙，手術方法採耳後進入，合併或不合併乳突鑿開術。結果：62例膽脂瘤手術，患者年齡平均44.5歲。自發性神經裂隙的發生率為46.8% (30/62)，醫源性神經裂隙的發生率為4.8% (3/62)。手術性裂隙的比率為51.6% (33/62)，所有手術性裂隙的病例中，其最低反應電流強度皆不大於0.5 mA，判定電流性顏面神經裂隙標準為0.5 mA，因此電流性裂隙的比率為79.0% (49/62)。術後所有病患都沒有顏面神經麻痺的現象，醫源性神經麻痺的比率為0%。結論：在膽脂瘤手術中常規使用顏面神經監測，對避免醫源性神經損傷、尋找神經走向、偵測顏面神經裂隙相當有價值。安全的手術是建立在對手術部位的熟悉及正確、熟練的手術行為上，針對高風險解剖位置的手術、修正性手術及耳科結構異常的病人，術中使用顏面神經監測更加有其必要性。

關鍵字

cholesteatoma ； mastoidectomy ； intraoperative facial nerve monitoring ； nerve injury ； facial nerve dehiscence（膽脂瘤 ； 乳突鑿開術 ； 術中面神經監測 ； 神經傷害 ； 面神經裂隙）

並列摘要

BACKGROUND: Cholesteatomas originate in the temporal bone and tend to invade adjacent structures, causing irreversible physiological dysfunction. Facial paralysis is likely to happen resulting from progression of the disease or iatrogenic injury. Facial nerve is even more vulnerable with the presence of facial nerve dehiscence. Intraoperative facial nerve monitoring (IFNM) helps to locate the facial nerve and dehiscence, which consequently prevents iatrogenic nerve injury. The purpose of the study was to share our experience of using IFNM during surgeries for cholesteatomas. METHODS: This retrospective study included 62 cases who underwent middle ear and mastoid surgeries for cholesteatoma. INFM was used in all cases to prevent nerve injury and locate the facial nerve. Facial dehiscence was also searched by surgical exploration and then detected by a monopolar stimulator. Surgical methods are post-auricular approach, with or without mastoidecotmy. RESULTS: There were 62 cases who underwent surgeries for cholesteatoma enrolled with mean age of 44.5 years old. Spontaneous dehiscence accounted for 46.8% (30/62) and iatrogenic dehiscence accounted for 4.8% (3/62). Surgical dehiscence was found in 51.6% of cases (33/62). Given that all dehiscent facial nerve responded to 0.5 mA or less, the cutting point of electrical dehiscence was 0.5 mA, which made 79.0% of cases (49/62) to be electrically dehiscent. No post-operative facial palsy was noted in all patients. CONCLUSIONS: The study concluded that routine use of IFNM is recommended in surgeries for cholesteatomas. Continuous facial nerve monitoring offers great aid in preventing iatrogenic facial nerve injury, mapping the course of facial nerve and detecting potential facial nerve dehiscence. It is undeniably that a surgeon's familiarity of the surgical anatomy is the cornerstone of safety when working in a high-risk surgical field. To adopt facial nerve monitor during surgery can further minimize the risk of unwanted facial nerve injury. The device is even more valuable when performing highrisk surgeries, revision surgeries and surgeries involving aberrant otologic structures.

並列關鍵字

cholesteatoma ； mastoidectomy ； intraoperative facial nerve monitoring ； nerve injury ； facial nerve dehiscence