脊椎骨内神经鞘瘤的 CT、MRI 表现 （附 11 例报道及文献复习）

目的 探讨脊椎骨内神经鞘瘤（Intraosseous Schwannoma,IOS）的特征性影像学表现,以与其他脊椎溶骨性病 变区别开。方法 回顾性分析上海交通大学医学院附属第九人民医院经手术病理证实的脊椎 IOS 的临床资料及 CT 、MRI 等 影像学资料。该文收集了 11 例脊椎 IOS 患者,其中男性 7 例,女性 4 例,年龄 23 ～ 74 岁［平均年龄（51 ± 17）岁］ 。所 有患者均行 CT 和 MRI 检查。由两名高年资骨关节系统放射科医师对所有影像学征象进行评估,并复习了近几年来文献报 告的脊椎 IOS 影像学征象。结果 病变累及部位包括颈椎 3 例（3/11, 27.3%）,胸椎 1 例（ 1/11, 9.1%）,腰椎 5 例（5/11, 45.5%）,腰骶椎 2 例（2/11, 18.2%）,最大径（5.8±2.85）cm,形态均为不规则形。CT 显示偏心性膨胀性溶骨性骨质破坏, 密度不均匀,平扫 CT 值为（43.0 ± 11.55 ）HU 。增强后不均匀轻度强化,CT 值为（70.3 ± 12.22 ）HU,病灶边界清晰,有硬 化缘,未见骨膜反应,病灶易沿着椎间孔向椎管内外延伸。在 MRI 上,与肌肉组织相比,病灶在 T1WI 上呈等稍低信号, 在 T2WI 上呈混杂稍高信号,压脂后呈混杂高信号,DWI 未见弥散受限,ADC 值为（1.25±0.176）× 10-3mm2/s,增强后不 均匀明显强化,时间 - 信号强度曲线为 I 型,7 例患者病灶内发生囊性变。结论 脊椎 IOS 是一种罕见的良性肿瘤,影像学 表现具有一定的特征性,在鉴别诊断边界清晰的具有异质性的脊椎溶骨性病变时应予以考虑。

Imaging Features of Intraosseous Schwannoma Involving the Spine: Eleven Case Series and Review of the Literature

Objective To explore the imaging features of intraosseous schwannoma (IOS) involving the spine in order to differentiate it from other spinal osteolytic lesions. Methods We retrospectively analyzed the clinical data, CT and MRI of IOS involving the spine confirmed by surgery and pathology in Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine. We collected 11 cases of IOS involving the spine, including 7 males and 4 females, aged 23-74 years [average age (51 ± 17) years]. All patients underwent CT and MRI examinations. Two senior bone and joint system radiologists evaluated the imaging features and reviewed literatures reported in recent years. Results The IOS involved 3 cases of cervical spine (3/11, 27.3%), 1 case of thoracic spine (1/11, 9.1%), 5 cases of lumbar spine (5/11, 45.5%), and 2 cases of lumbosacral spine (2/11, 18.2%), with a maximum diameter of (5.8 ± 2.85) cm and an irregular shape. CT showed eccentric expansive osteolytic bone destruction with uneven density. The average CT values on plain scan were (43.0 ± 11.55) HU. After enhancement, the lesions showed uneven mild enhancement, with an average CT value of (70.3 ± 12.22) HU. The boundaries of the lesions were clear, with sclerotic edges and no periosteal reaction. The lesions were prone to extend along the intervertebral foramen to the inside and outside of the vertebral canal. On MRI, compared with muscle tissue, the lesions showed equal low signal intensity on T1WI,mixed slightly high signal intensity on T2WI, mixed high signal intensity after fat suppression, and no diffusion limitation on DWI with the average ADC value of 1.25 ± 0.176 × 10-3mm2/s. After enhancement, the lesions showed uneven and significant enhancement, with a time signal intensity curve (TIC) of type I and cystic changes occurring in 7 lesions. Conclusion IOS involving the spine is a rare benign tumor with certain characteristic imaging features, which should be considered in the differential diagnosis of heterogeneous spinal osteolytic lesions with clear boundaries.