仰卧头偏侧体位处理侧后颅窝病变的价值研究

A study of the value of supine position with head laterally fixed in the treatment of lesions of the lateral part of posterior cranial fossa

目的研究仰卧头偏侧体位开颅显微手术入路在处理侧后颅窝病变的临床价值。方法对2017年1月~2019年6月在我科手术治疗的22例一侧后颅窝病变患者进行回顾性研究。其中表皮样囊肿2例,脑膜瘤3例,星形胶质细胞瘤5例,转移瘤2例,血管母细胞瘤1例,血肿3例,听神经瘤2例,蛛网膜囊肿2例,小脑梗死2例。手术采取仰卧位,垫高患侧肩并向背尾侧拉肩,头转向一侧并屈颈的头偏侧体位。常规依据病灶部位使用乙状窦后、经横窦中点直切口。结果该体位对一侧后颅窝病变暴露理想,所有患者除2例因原发病死亡,1例蛛网膜囊肿开窗不理想转外院手术外,其余均预后良好。结论仰卧头偏侧体位显微手术能有效暴露小脑岩面裂隙至小脑蚓旁病变。头端可探查小脑山坡,尾端可探查小脑扁桃体。可以处理大部分后颅窝病例,但跨中线的小脑蚓正中病变及四脑室病变手术处理可能有困难。

Objective To study the clinical value of microsurgical craniotomy approach in supine position with head laterally fixed in treating lesions of the lateral part of posterior cranial fossa.Methods A retrospective study was conducted on 22 cases of lesions of unilateral posterior cranial fossa receiving operative treatment in our department from January 2017 to June 2019.Among them,there were 2 cases of epidermoid cyst,3 cases of meningioma,5 cases of astrocytoma,2 cases of metastatic tumor,1 case of hemangioblastoma,3 cases of hematoma,2 cases of acoustic neuroma,2 cases of arachnoid cyst and 2 cases of cerebellar infarction.The operation was performed in supine position with head laterally fixed characterized by affected shoulder being raised and the shoulder being pulled toward the back,the head turned to one side and a bent neck.Conventionally,in light of the location of the lesion,a straight incision was made with the retrosigmoid sinus and through the midpoint of the transverse sinus.Results This position is ideal for exposing lesions of unilateral posterior cranial fossa.All cases had good prognosis,except two cases of death caused by primary disease and one case of arachnoid cyst transferred to other hospitals because of the unsatisfying fenestration.Conclusion Microsurgery in supine position with head laterally fixed can effectively expose cerebellar petrosal fissure to the lesions around cerebellar vermis.The clivis can be detected by the head end,and the cerebellar tonsil can be detected by the tail end.It can treat most lesions of posterior cranial fossa,but it might hardly treat cross midline lesions of median cerebellar vermis and the lesions in the fourth ventricle.