青光眼视网膜神经纤维损害激光偏振光扫描测量的价值

Clinical observation of the damage of retinal nerve fiber layer in glaucoma

目的:探讨青光眼的视网膜神经纤维层缺损特征,评价激光偏振光扫描测量仪(GDxVCC)在青光眼早期诊断方面的应用价值。方法:采用激光偏振光扫描测量仪(GDxVCC,美国)对60例110眼正常人及46例85眼青光眼患者视网膜后极部水平方向40°、垂直方向20°范围进行激光偏振光扫描测量视网膜神经纤维层厚度(RNFL),同时进行中央30°视网膜光阈值检查(Humphrey视野分析仪,Central30-2thresholdtest,美国),并对结果进行统计分析。结果:正常眼RNFL厚度与性别、眼别无关,而与年龄呈负相关;各期青光眼患者的RNFL均值显著低于正常对照组(年龄匹配,P<0.01);早期、进展期、晚期青光眼患者的RNFL厚度均值比较也有显著性差异(P<0.001)。GDxVCC检测RNFL厚度值与Humphrey视野检查指数平均缺损值(MD)具显著正相关性(r=0.795,P<0.001)。青光眼的视网膜神经纤维层图像可表现为局限性变薄或缺损(85.2%)、弥漫性变薄(6.6%)、弥漫性变薄并局限性缺损(8.2%),以鼻上方的局限性变薄或缺损最常见(56.7%)。有23.3%的早期青光眼患者视野检测正常而GDxVCC检测发现有不同程度的视网膜神经纤维层缺损。结论:GDxVCC能准确定量检测RNFL厚度值,视网膜神经纤维层的检测能比视野检测更早地发现青光眼的视神经的损害,因而可作为青光眼患者早期诊断的重要指标之一。随着青光眼患者病情的发展,RNFL厚度逐渐变薄,视野的平均缺损值逐渐增加。GDxVCC联合视野检查对于追踪青光眼患者的病情变化,确立靶眼压的水平,制定个性化的治疗方案有着重要的价值。

AIM： To study the characteristics of retinal nerve fiber layer defect in glaucoma and to evaluate the value of GDxVCC in the early diagnosis of glaucoma. METHODS： Forty-six normal persons （85 eyes） and 60 cases （110 eyes） with glaucoma were tested by GDxVCC with laser polarized light scans in a field of 40° horizontally and 20° vertically to measure the thickness of retinal nerve fiber layer and with the light sensitivity test in the central 30 degree field （Humphrey field analyzer, American）. Finally, the results were analyzed statistically. RESULTS： The decrease of the retinal nerve fiber layer thickness with aging was found in normal Chinese, but there was no statistically significant difference between left and right eye, neither did the sex. Mean thickness of retinal nerve fiber layer at each stage of glaucoma was thinner significantly than that of normal controls （age matched, P〈0.01）; Mean thickness of retinal nerve fiber layer was strongly related to the visual index Mean Defect （r=0.795,P〈0.001）.The retinal nerve fiber layer of glaucoma patient showed local thinness or defect （85.2%）, diffuse thinness （6.6%）or combination of the above two types （8.2%）, especially local thinness or defect happened commonly in nasal superior （56.7%）. The 23.3 percent of early glaucoma patient was found to have different degree retinal nerve fiber layer defect whose visual field was normal. CONCLUSION： GDxVCC can quantitatively measure the thickness of retinal nerve fiber layer accurately ,the measurement of retinal nerve fiber layer is more early than visual field to find optic nerve damage of glaucoma, so it may become one of the important indices of the early diagnosis of glaucoma. The RNFL thickness is gradually decreased while visual field defect is increased with the development of glaucoma. GDxVCC combining with visual field plays an important role in observing the development of glaucoma, finding the level of target intraocular pressure, establishing individual treatment plan.