经枕下乙状窦后入路切开头后大直肌在听神经瘤手术中小脑保护的临床分析

Clinical analysis on cerebellar protection by dissection of musculi rectus capitis posterior major in acoustic neuroma surgery via suboccipital retrosigmoid approach

目的 探讨和总结听神经瘤手术中小脑牵拉损伤危险因素及保护策略。方法 回顾性分析2020年1月—2023年5月于首都医科大学三博脑科医院神经外科六病区手术治疗的46例原发听神经瘤患者的临床资料,其中男22例,女24例;年龄(51.4±16.5)岁。病灶位于左侧20例,右侧26例;肿瘤平均直径(32.0±10.8)mm;平均手术时间5 h 20 min。所有患者均行枕下乙状窦后开颅,其中开颅过程中分层切开肌肉并切开头后大直肌33例,传统开颅技术且未切开头后大直肌13例。所有患者术后1周左右行颅脑MRI检查,T2相及FLAIR相评估术后小脑是否牵拉损伤。结果 所有患者术中无椎动脉损伤,术后无死亡病例。46例患者术后早期MRI检查提示有14例患者出现小脑牵拉损伤(30.4%),其中33例开颅过程中切开头后大直肌组术后MRI检查提示小脑牵拉损伤为7例(21.2%);13例未切开头后大直肌组中小脑牵拉损伤7例(53.8%)。本组患者通过Spearman多因素相关性分析听神经瘤术后小脑牵拉损伤与开颅过程中是否切开头后大直肌具有相关性(P<0.05);与肿瘤侧别、患者年龄、肿瘤最大径、手术时长无相关性(P>0.05)。结论 听神经瘤手术开颅过程中切开头后大直肌可通过扩大骨瓣下方暴露范围,术中容易释放枕大池的脑脊液,可降低术中对小脑牵拉损伤的风险。

Objective To explore and summarize the risk factors and protective strategies of cerebellar traction injury in acoustic neuroma surgery.Methods A retrospective analysis was performed on clinical data of 46 patients with primary acoustic neuroma who underwent surgical treatment in our department from January 2020 to May 2023.There were 22 males and 24 females,with an average age of(51.4±16.5)years.The lesions were located on the left side in 20 cases and on the right side in 26.The average tumor diameter was(32±10.8)mm,and the average operation time was 5 hours and 20 minutes.Craniotomy was performed in all patients via suboccipital retrosigmoid approach.During the craniotomy,33 cases underwent layer-by-layer muscle incision combined with dissection of musculi rectus capitis posterior major,while 13 cases received conventional incision without dissection of musculi rectus capitis posterior major.About one week after surgery,all patients underwent head magnetic resonance imaging examination,T2 and liquid attenuated inversion recovery(FLAIR)phases were used to evaluate whether the cerebellum was pulled and damaged.Results There were no postoperative deaths and no vertebral artery injuries in all patients.Early postoperative magnetic resonance imaging examinations of the 46 patients indicated that 14(30.4%)had cerebellar traction injury.Of them,7 cases(21.2%)were from the 33 patients with dissection of musculi rectus capitis posterior major,and 7(53.8%)from the 13 cases without dissection of musculi rectus capitis posterior major.Spearman’s multi-factor correlation analysis showed a statistically significant correlation between cerebellar traction injury and whether the musculi rectus capitis posterior major was dissected during craniotomy in acoustic neuroma surgery(P<0.05).There were no correlations between cerebellar traction injury and tumor laterality,patient’s age,maximum tumor diameter,and operation time(P>0.05).Conclusion During craniotomy in acoustic neuroma surgery,dissection of musculi rectus capitis posterior major can expand the exposure scope under bone flap,thus facilitate releasing cerebrospinal fluid from the foramen magnum region and reducing the risk of cerebellar traction injury.