听神经鞘瘤CT、MR诊断与鉴别诊断

CT and MR Diagnosis and Differential Diagnosis of Acoustic Neurilemmoma

目的回顾总结听神经鞘瘤临床表现及CT、MRI影像表现,旨在提高听神经鞘瘤术前诊断的准确性。方法对55例病理诊断为听神经鞘瘤病例的临床资料及CT、MRI影像表现进行回顾性分析。结果55例患者中,双侧发病1例,单侧发病有54例;肿瘤伴囊变出血3例,血栓形成1例,52例密度及信号均匀,3例密度及信号混杂;38例内听道受侵犯,表现为内听道不同程度增大,部分呈漏斗状,12例患侧岩骨骨质不同程度吸收破坏,54例听神经鞘瘤外缘灶性突起并伸入内听道内,55例瘤周未见明确水肿带。55例患侧桥脑小脑角池扩大,脑桥、桥臂及小脑半球不同程度受压,第四脑室不同程度受压变形,向健侧移位,40例出现梗阻性脑积水。结论听神经鞘瘤作为桥小脑角区最常见的良性肿瘤,根据该肿瘤发病部位、密度以及信号、生长方式以及对内听道形态的改变,我们能作出明确诊断,为临床手术方案的制定提供重要意见。

Objective To retrospectively summarize the clinical manifestations,CT and MRI findings of acoustic neurilemmoma,in order to improve the accuracy of preoperative diagnosis of acoustic neurilemmoma.Methods The clinical data,CT and MRI findings of 55 cases of acoustic neurilemmoma diagnosed by pathology were retrospectively analyzed.Results Among 55 cases,1 case was bilateral,54 cases were unilateral,3 cases were cystic hemorrhage,1 case was thrombosis,52 cases were homogeneous in density and signal,3 cases were mixed in density and signal,38 cases were invaded by the internal auditory canal,showing different degrees of enlargement of the internal auditory canal,part of which was funnel shaped,12 cases were absorbed by the petrous bone in different degrees.Fifty-four cases of acoustic neurilemmoma were destroyed.Focal protrusions at the outer edge of the acoustic neurilemmoma extended into the internal auditory canal.No edema zone was found around the tumor in 55 cases.55 cases had enlarged pool of cerebellopontine angle,compression of pons,brachiopontine and cerebellar hemisphere,compression and deformation of the fourth ventricle to the contralateral side,40 cases had obstructive hydrocephalus.Conclusion Acoustic neurannoma is the most common benign tumor in the corner area of the cerebellum.A definite diagnosis can be made according to the location,density and signal intensity of the tumor,the mode of growth and the morphological changes of the internal auditory canal,which provides important suggestions for the formulation of clinical surgical plan.