耳内镜下外耳道“锁孔”技术处理累及乳突的中耳胆脂瘤的初步实践

Application of External Auditory Canal“Key Hole”Technique in Endoscopic Management of Middle Ear Cholesteatoma Involving Mastoid Process:Preliminary Results

目的本文旨在探索耳内镜手术中的“锁孔”技术在中耳胆脂瘤手术中的临床应用价值。方法2017年1月至2018年12月间收治的65名单侧中耳胆脂瘤患者,27例患者术前的颞骨CT提示低密度影及骨质破坏局限于上鼓室,鼓窦和乳突区域未见异常;38例患者术前的颞骨CT显示上鼓室内形成的低密度影像,存在骨质破坏,而鼓窦及乳突内也存在类似的低密度影像,难以确定病变是否累及乳突腔。术中耳内镜下经耳道“锁孔”技术早期探查上鼓室、鼓窦和后方的乳突腔内的空间,确定胆脂瘤范围,修正手术方案、优化手术策略。结果术前通过颞骨薄层CT显示的胆脂瘤仅局限于上鼓室的27例患者中,其中17例患者的影像学病变范围与“锁孔”技术探查结果吻合;另外10例病变累及鼓窦及乳突。术前38例患者的影像学显示上鼓室胆脂瘤可能累及鼓窦和乳突,术中通过“锁孔”技术验证,29例为上鼓室胆脂瘤侵及乳突;9例为堵塞形成的黏膜增厚及肉芽组织等非胆脂瘤病变。患者术后随访时间均超过了2年,随访方式为耳内镜及颞骨CT,8例患者的鼓窦及乳突区存在可疑软组织影,进行了便捷的内镜下“锁孔”的探查,鼓窦及乳突区未见胆脂瘤复发,软组织影为增厚黏膜及肉芽。结论在耳内镜下经外耳道径路,可结合持续灌流模式,在耳道后上壁快速开放直径4-6mm的骨窗,通过“锁孔”可以早期明确和判断中耳胆脂瘤累及乳突、鼓窦、上鼓室的病变范围,有利于修正手术方式,减少不必要的骨质磨除,更利于微创的实现和便于手术中耳道重建。

Objective To evaluate clinical values of the"key hole"technique in endoscopic management of middle ear cholesteatoma.Methods A retrospective analysis was taken with respect to 65 patients with unilateral middle ear cholesteatoma admitted to our department between January 2017 and December 2018.Twenty-seven out of the 65 patients’preoperative temporal bone CT results showed low-density lesions and bone destruction confined to the epitympanum and normal antrum and mastoid cavity in 27 patients and suspected extension of lesions and bone destruction into the antrum and mastoid in the remaining 38 patients,in whom the"key hole"technique was used during the early stage of endoscopic operation to explore the epitympanum,tympanic antrum and mastoid,and confirm the location of cholesteatoma in comparison with CT findings.This allowed adjustment of surgical strategy when indicated.Results Exploration by the"key hole"technique confirmed CT results in 17 of the 27 patients whose preoperative CT scans showed cholesteatoma confined to the epitympanum,but showed epithelial sac extension into the antrum and mastoid in the other 10 patients.For the 38 patients whose preoperative CT results suggested cholesteatoma involving the epitympanum,antrum and mastoid,intraoperative findings were consistent with preoperative CT results in 29 cases,but showed only thickened mucosa and granulation tissue in the mastoid in the other 9 cases.During more than 2 years of postoperative follow-up by temporal bone CT,soft tissue shadows in the antrum and mastoid were seen in 8 patients,but cholesteatoma recurrence was ruled out by the easy and convenient endoscopic inspection through the key hole(second look).Conclusion Via the endoscope transcanal approach,surgeons can easily confirm the location and extent of cholesteatoma lesions through a small 4-6 mm hole on the posterior-superior external canal wall(key hole),which is not only helpful for adjusting surgery strategy at an early stage of surgery,but can also reduce unnecessary bone removal.