相干光断层扫描检测Leber遗传性视神经病变视网膜神经纤维层厚度改变

摘要

目的 研究Leber遗传性视神经病变(LHON)携带者和各发病阶段患者的视网膜神经纤维层(RNFL)厚度变化特征.方法 病例对照研究.纳入经临床诊断和线粒体基因检测确诊的G11778A突变型LHON家系母系成员42例,其中LHON携带者组15例,包括眼底正常者10例,临床前期者5例；LHON患者组27例,包括早期患者9例,进展期患者5例,晚期患者13例.正常对照组1 00例.应用Stratus OCT 3000测量所有受试者的RNFL厚度,并分别计算正常对照组、LHON携带者组及LHON患者组的颞侧、上方、鼻侧、下方象限及全周RNFL厚度.组间各象限及全周RNFL厚度比较采用单因素方差分析,多个均数间的两两比较采用LSD-t检验(该软件仅提供P值).结果 LHON患者组病变早期颞侧、上方、鼻侧、下方象限及全周RNFL厚度分别为(97.3 ±8.7) 、(159.5±16.2)、(91.8±9.6)、(168.6±16.2)及(129.3±5.7)μm,较正常对照组增厚,至病变进展期和晚期各象限及全周RNFL厚度呈递进变薄趋势.LHON患者组、LHON携带者组及正常对照组间颞侧、上方、鼻侧、下方象限及全周RNFL厚度比较,差异均有统计学意义(F=33.094,35.350,25.04,81.619,183.982;P ＜0.05).眼底正常的LHON携带者各象限和全周RNFL厚度均正常；临床前期与早期LHON患者的各象限及全周RNFL厚度差异均无统计学意义(P=0.138～0.645)；但是临床前期与早期患者的颞侧、上方、下方象限及全周RNFL厚度均较正常对照组和眼底正常的LHON携带者明显增厚(P=0.000 ～0.018).进展期和晚期LHON患者的颞侧、下方象限及全周RNFL厚度分别较正常对照者、临床前期LHON携带者及早期LHON患者明显变薄(P=0.000 ～0.005).晚期LHON患者的各象限及全周RNFL厚度分别较正常对照者、LHON携带者、早期和进展期LHON患者明显变薄(P=0.000 ～ 0.037).结论 LHON临床前期携带者和不同发病阶段患者的RNFL厚度均有改变.LHON病变早期颞侧、上方及下方象限RNFL均明显增厚,进展期颞侧和下方象限RNFL变薄,晚期各个象限均显著变薄.%Objective To evaluate retinal nerve fiber layer (RNFL) thickness in patients and unaffected carriers of Leber hereditary optic neuropathy (LHON) by optical coherence tomography (OCT).Methods This case-control study enrolled 42 LHON maternal family members with mitochondrial DNA G11778A mutation and 100 normal volunteers.RNFL thickness was measured by Stratus OCT in each participant.Mean RNFL thickness of each quadrant,as well as 360° average were calculated and compared in normal controls,LHON carries and LHON patients.Results Among LHON maternal family members,15 cases were unaffected carriers who were subgrouped as normal-fundus-appearing carriers (10 cases) and preclinical carriers (5 cases).Twenty seven LHON patients included 9,5,and 13 cases in the early,advancing and advanced stages,respectively.Normal fundus-appearing carriers showed normal RNFL thickness of each quadrant and 360° average.Preclinical carriers and early-staged patients showed no significant difference in RNFL thickness of each quadrant and 360° average(P =0.138 to 0.645),yet both showed thicker RNFL in temporal,superior and inferior quadrant,as well as 360° average,if compared with normal controls (P =0.000 to 0.018).Compared with normal controls,preclinical carriers and early-staged patients,advancing LHON patients showed thinner RNFL in temporal and inferior quadrant,as well as 360° average (P =0.000 to 0.005).Advanced LHON patients showed thinner RNFL in each quadrant and 360° average,compared with normal controls,LHON carriers,and advancing cases (P =0.000 to 0.037).Conclusions RNFL thickness in LHON patients and unaffected carriers was characterized by OCT in this study,which would improve the understanding of the natural course of LHON.