应用海德堡视网膜断层扫描仪检测开角型青光眼的视盘改变

目的探讨海德堡视网膜断层扫描仪(Heidelberg retinal tomography,HRT)检测青光眼性视盘改变是否与视野损害的部位相一致,了解正常眼压性青光眼(normal tension glaucoma,NTG)与原发性开角型青光眼(primary open angle glaucoma,POAG)早或中期视盘形态是否异同.方法对64例(64只眼)仅有半侧视野异常的开角型青光眼(POAG27只眼、NTG37只眼)患者进行HRT检测,将Humphery视野与HRT的检测结果以0°～180°为界,分成上下两部分进行对应分析.结果与正常半侧视野对应的1/2视盘比较,显示异常半侧视野对应的1/2视盘HRT参数中,杯盘面积比、视杯形态测量值显著增大,而盘沿面积、视网膜神经纤维层厚度及视网膜神经纤维层横断面积值显著减少 (t=-2.625～3.025,P=0.003～0.05);NTG眼和POAG眼对应与异常半侧视野的HRT视盘参数差异无显著性(t=-0.98～1.511,P=0.14～0.97).结论 HRT参数能较准确反映与视野损害相一致的视盘变化,其中尤以杯盘面积比、盘沿面积、视杯形态测量、平均视网膜神经纤维厚度及视网膜神经纤维层横断面积测量值较为准确.NTG和POAG眼的视盘形态相似,可能具备某些相似的视神经损害发生机制.

Evaluation of optic disc in open-angle glaucoma with hemifield defect by Heidelberg retinal tomography

OBJECTIVE: To investigate whether the glaucomatous optic disc change demonstrated by Heidelberg retinal tomography (HRT) is consistent to the distribution of the visual field defects and whether Heidelberg retinal tomography, (HRT) parameters in primary open angle glaucoma (POAG) and normal tension glaucoma (NTG) are different. METHOD: Sixty-four eyes of 64 patients with open angle glaucoma (27 of POAG, 37 of NTG) and hemifield abnormality detected by Humphery Field Analyzer (HFA) were tested by HRT. The HRT parameters and the visual field results were divided into two parts (0 degree-180 degrees and 180 degrees-360 degrees) for the corresponding analysis. RESULTS: Comparing with the half disc corresponding to the intact hemifield, the half disc corresponding to the defective hemifield has significantly higher values of cup/disc area ratio and cup shape measure, but has significantly lower values of rim area, the thickness and cross-section area of the retinal nerve fiber layer. No significant differences were found between NTG and POAG eyes in the HRT parameters of the half disc corresponding to the defective hemifield. CONCLUSIONS: The optic disc changes detected by HRT are consistent to the distribution of the visual field defects, cup/disc area ratio, cup shape measure, rim area, mean thickness and cross-section area of the retinal nerve fiber layer, and they are the relatively sensitive parameters. That the HRT parameters of NTG and POAG are similar suggests they possibly have certain similar mechanisms in the development of glaucomatous neuropathy.