视神经脊髓炎患者41例视神经磁共振分析

目的:探讨视神经脊髓炎(neuromyelitis optica,NMO)患者视神经的MRI表现特点。方法:对临床疑似NMO患者进行视神经、脑部和脊髓扫描,将满足NMO最新Wingerchuk诊断标准的41例患者纳为研究对象,进行随访研究,分析不同病程阶段视神经MRI表现特点,并与32位健康志愿者进行对照。同时,回顾性分析患者视神经诱发电位(visual evoked potential,VEP)检查结果,探讨MRI表现与VEP之间的关系。结果:正常志愿者MRI显示双侧视神经走行笔直,部分节段视神经鞘膜腔表现为稍高信号,但“双轨样”改变不明显。而NMO患者最常见的异常改变为视神经鞘膜腔信号显著增高,呈全程连续性“双轨样”改变,较健康志愿者明显不同。急性期,22例患者(53.7%)伴有视神经增粗或(和)扭曲； 17例(41.5%)可见视神经内点状高信号表现；31例(75.6%)在横断位T1WI上可见到视神经强化。缓解期,15例(36.6%)MRI上可见单侧或双侧视神经萎缩、变细和(或)扭曲。在本组研究结束时,共35例(80.5%)视神经内见点状高信号表现。对照VEP检查结果,MRI在反映视神经脱髓鞘改变上,敏感性为94.6%,但在急性期仅为43.6%,说明MRI检查具有一定的时间依赖性,不及VEP敏感。 结论:MRI能清晰显示NMO患者各个病理阶段视神经的形态改变,MRI可以成为视神经的首选影像学检查方法。

Optic magnetic resonance imaging findings in 41 patients with neuromyelitis optica

Objective:To investigate the optic magnetic resonance imaging (MRI) findings in patients with neuromyelitis optica (NMO).Methods: Patients with suspected NMO underwent brain,spinal cord and the optic MRI scanning and imaging analysis;41 patients who met the latest diagnosis criteria of NMO were enrolled in the present study and were the followed up.The MRI characteristics of the optic nerves at different stages were analyzed,and 32 healthy volunteers served as control.The results of visual evoked potential (VEP) were analyzed retrospectively to investigate whether there was difference between the positive rate of VEP and MRI findings.Results: MRI imaging showed that the shape of bilateral optic nerves was straight in healthy volunteers,and just a moiety of the optic showed slightly higher signal.In NMO patients,signals of the optic at unilateral or bilateral side were obviously intensified and appeared like railway lines,which was different from healthy volunteers.In acute phase,22 (53.7%) patients were accompanied by optic swelling and/or distortion,31 (76.5%) had enhanced T1WI,and 17 (41.5%) had high-point signal in the optic nerve.In the remission stage,15 (36.6%) had their optic nerves atrophied,thinned or even distorted on unilateral and/or bilateral side.At the end of the study,35 (80.5%) showed high-point signal in the optic nerve.The overall sensitivity of MRI was 94.6%,but in acute phase the sensitivity was just 43.6%,indicating the sensitivity of MRI was time-dependent and was not as sensitive as VEP.Conclusion: MRI can clearly demonstrate the changes at different stages of optic nerve atherosclerosis in NMO patients.MRI may be the first choice for diagnosis of NMO.