高眼压性和正常眼压性原发性开角型青光眼视神经损害特征的比较

A comparative study of optic nerve damage between primary open angle glaucoma and normal tension glaucoma

目的探讨高眼压性原发性开角型青光眼(POAG)和正常眼压性青光眼(NTG)患者视神经损害的不同特点。方法应用德国Heidelberg公司生产的视网膜断层扫描仪对高眼压性POAG39例(47只眼)和NTG32例(38只眼)进行定量视盘参数和神经纤维层检查,并行眼底立体照相观察视网膜神经纤维层(RNFL)缺损类型,检测静态定量视野,并对检查结果进行比较。结果(1)NTG组视盘总体参数和分区(除颞侧外)盘沿面积、沿/盘面积小于高眼压性POAG组,而C/D大于高眼压性POAG组;平均RNFL厚度和RNFL面积在颞下和颞上小于高眼压性POAG组;总体盘沿容积小于高眼压性POAG组,总体平均视杯深度和颞下视杯面积大于高眼压性POAG组,两组差异均有统计学意义(P<005)。两组颞侧视盘各参数比较,差异无统计学意义(P>005)。(2)RNFL缺损类型高眼压性POAG组RNFL弥漫性缺损占5319%,局限性缺损占426%;NTG组弥漫性缺损占2105%,局限性缺损占5526%。两组RNFL缺损类型构成比比较,差异有统计学意义(P<001)。结论NTG较高眼压性POAG具有较大的C/D值、C/D面积比和窄盘沿面积,RNFL丢失严重。高眼压性POAG患者的RNFL以弥漫性缺损为主,NTG患者的RNFL以局限性缺损为主。两者视神经损害具有不同特点,其损害机制可能不同。(中华眼科杂志,2005,41136140)

Objective To investigate the differences in the characteristics of optic nerve damage in patients with primary open angle glaucoma(POAG)and normal tension glaucoma (NTG). Method The optic disc parameters and retinal nerve fiber layer (RNFL) of 47 eyes of 39 subjects with POAG (IOP>24 mm Hg) and 38 eyes of 32 subjects with NTG (IOP<21 mm Hg) were measured by using a Heidelberg retina tomograph Ⅱ, color stereo-optic disc photographs, and an Octopus automated perimetry. Results^(1)Rim area, rim/disc area ratios and three sectors except temporal quadrant of optic disc were significantly smaller,whereas C/D was significantly larger in patients with NTG than those of POAG. The mean RNFL thickness and RNFL cross-sectional areas at temporal/interior and temporal/superior in those with NTG were significantly (P<0.05) smaller than those of POAG. The rim volume was significantly (P<0.05) smaller and mean cup depth was significantly (P<0.05) larger in patients with NTG than POAG.(2)The defect types of RNFL: RNFL diffuse loss and local defect ratio were 53.19% and 4.26%in POAG, respectively; while were 21.05% and 55.26%in NTG, respectively.The difference between the proportions of the defect type of RNFL in patients with POAG and those of NTG is statistically significant (P<0.01). Conclusions^Our results demonstrate that the varieties of C/D area ratio, rim area, RNFL thickness, and defect types of RNFL with NTG and POAG indicate that the different mechanisms are involved in optic nerve damage in the two types of glaucoma.(Chin J Ophthalmol,2005,41:136-140)