视神经炎的MRI表现及与视觉诱发电位的相关性研究

目的 探讨诊断视神经炎的有效MR检查序列、MRI表现及其与视觉诱发电位(VEP)的相关性.方法 对98例(154只眼)诊断为视神经炎、视神经乳头炎、多发性硬化、视神经脊髓炎的视力下降患者MRI资料进行分析,并与VEP结果及临床视力表现做x2检验、秩和检验和一致性分析.结果154只患眼中56条视神经增粗,76条形态不变,22条变细.MR短时间反转恢复(STIR)序列显示132条视神经呈异常高信号.异常信号累及范围包括视神经球壁段7条,眶内段135条,管内段109条,颅内段97条,视交叉受累56例,视束受累23条.54例行钆喷替酸葡甲胺(Gd-DTPA)增强枪查者,87只患眼中74条视神经强化.98例患者共196只眼中,视力下降同时视神经MRI信号异常者132只眼,视力正常、视神经MRI信号正常者26眼,MRI与视力表现之间的一致率为80.61%(Kappa=0.453,P＜0.01).住获得VEP结果的175只眼中,视力下降同时VEP异常者129只眼,视力正常、VEP正常者30只眼,VEP与视力表现之间的一致率为90.86%(Kappa=0.731,P＜0.01);视神经MRI信号异常及VEP异常者117只眼,MRI信号正常、VEP正常者24只眼,MRI表现与VEP之间的一致率为80.57%(Kappa=0.460,P＜0.01).结论MR STIR序列和Gd-DTPA增强扫描联合脂肪抑制技术有助于视神经炎定位和定性诊断,VEP有助于视神经炎的诊断和亚临床病灶发现,MRI结合VEP能提高视神经炎诊断的准确率.

MRI findings and correlative study of MRI and visual evoked potentials in optic neuritis

Objective To investigate the effective MRI sequences and describe the correlation between MRI and visual evoked potential(VEP)in diagnosing optic neuritis.Methods One hundred and fifty-four eyes with visual impairment of 98 patients with diagnoses of optic neuritis,papillitis,multiple sclerosis and Devic's disease underwent MRI and VEP examination. The MRI findings were analyzed and correlated with VEP results and clinical presentation by using x2 test,wilcoxon test and Kappa test.Results Out of the 154 sick eyes.56 eyes presented thickened optic nerves.76 eyes had normal diameter of the optic nerve,and 22 eyes had thin optic nerves.A total of 132 optic nerves showed abnormally high signal in STIR sequences.including involvement of intraocular segment in 7,intraorbitsl segment in 135,intracanalicular segment in 109,intracranial segment in 97,optic chiasm in 56,and optic tract in 23.A total of 54 patients underwent postcontrast MRI. Seventy-four optic nerves of 87 eyes showed enhancement.Among the 196 eyes of 98 patients,132 eyes presented visual impairment and simultaneous abnormal MR signal of the optic nerve.and 26 eyes had both normal vision and normal MR signal of optic nerve.The consistency of MRI findings and vision status was 80.61%(Kappa=0.453,P＜0.01).Among the 175 eyes with VEP results.129 eyes had visual loss with simultaneous VEP abnormalities,and 30 eyes had both normal vision and normal VEP results.The consistency of VEP and vision status was 90.86%(Kappa=0.731,P＜0.01).Among the 175 eyes with VEP results,117 eyes had abnormal MR signal of the optic nerve and simultaneous abnormal VEP,and 24 eyes had both normal MR signal of the optic nerve and normal VEP.The consistency of MRI findings and VEP was 80.57%(Kappa=0.460,P＜0.01).Conclusion STIR sequence and gadolinium-enhanced T1-weighted MR sequence combined with fatsuppression are helpful in diagnosis of optic neuritis.VEP is helpful in diagnosing optic neuritis and in finding subclinical visual problem.The MRI combined with VEP could improve the diagnostic accuracy of optic neuritis.