椎管闭合不全的MRI诊断(附27例分析)

MRI diagnosis of spinal dysraphism(analysis of 27 cases)

目的:分析椎管闭合不全的MRI表现特点,评价MRI诊断和鉴别诊断的价值。方法:回顾性分析27例椎管闭合不全的MRI资料,经手术证实9例,MR表现典型18例。结果:MRI显示偏侧脊髓脊膜膨出1例,腰段椎管后裂开,脊髓裂开,左侧脊髓脊膜向后膨出。脊髓纵裂2例,脊髓硬膜囊被骨性或纤维间隔分开。脂肪脊髓裂5例,骶管裂开且皮下脂肪突入椎管内,脂肪瘤—基板界面位于骶管内。脂肪脊髓脊膜膨出2例,腰骶管后裂开且腰骶皮下脂肪瘤通过裂口疝入硬膜下,横断位见脂肪瘤—基板界面位于骶管外。脊膜膨出6例,腰骶背部皮下囊状突出物与蛛网膜下腔脑脊液相通。硬膜下脂肪瘤4例,硬膜下病变在T1WI及T2WI上呈高信号。终丝脂肪瘤4例,T1加权像上见终丝结节状、线条状脂肪信号。椎管内畸胎瘤2例,硬膜囊内不均匀信号团块状占位。骶管内脊膜囊肿1例,骶管内椭圆形在T1WI呈低信号,T2WI呈高信号影。结论:每型椎管闭合不全有相应的MRI表现特点,大多数MRI可准确诊断。

Objective： To analyze MRI features of spinal dysraphism in confirming MR diagnosis to it. Methods： To study MRI imagings of 27 spinal dysraphisms retrospectively. 9 cases were proved by operation and 18 cases were shown typically MR imagings. Results： MR imaging features were as follow： In 1 case with hemimyelomeningocele, lumbar spinal bifida, focal spinal cord was split and the left half was myelomeningocele. In 2 cases with split cord malformation, spinal cord or dural sac were separated by bony or fibrous septum. In 5 cases with lipomyeloschisis, subcutaneous lipoma projected into sacral canal which was bifida, lipoma/placode interface located into sacral canal. In 2 cases with lipomyelomeningocele, lurabar sacral spine bifida and subcutaneous lipoma of lumbar sacral herniated into subdural, lipoma/plaeode interface located outside sacral canal. In 6 cases with meningoeele, lumbosacral dorsal subcutaneous cystic mass connecting with subararchnoid space. In 4 eases with intradural lipoma, subdural lesion with high signal on T1WI and T2WI. In 4 cases with lipoma of ilium tenninale, on T1WI filum terminal had nodular or stringed lipoma signal. In 2 cases with spine canal teratoma, heterogeneous signal mass in the dural sac. In 1 case with spinal meningeal cyst, ovoid cyst with low signal on T1WI and high signal on T2WI in the sacral canal. Conclusion： Each type of spinal dysraphism had its corresponding MRI fcatures, MRI could diagnosis most of them precisely.