Ophthalmoscopic image characteristics and relation with vision and course of disease in nonarteritic anterior ischemic optic neuropathy

Abstract

Objective To observe the characteristics of fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) in nonarteritic anterior ischemic optic neuropathy (NAION),and investigate its relation with visual acuity and course of disease. Methods The clinical data of 47 patients (47 eyes) with NAION were retrospectively analyzed. All the patiens had undergone visual acuity, fundus and visual field examination ,meanwhile FFA and OCT were carried out at first visit. FFA and visual field were carried out by routine. OCT was carried out by line and circle shape scanning in macula and optic disc.Thirty-five NAION patients were checked with OCT at half, one, two, three and six month after onset in respectively. Take the healthy fellow eyes of 36 NAION patiens as control group. The FFA, visual field, OCT characteristics and relation with visual acuity and course disease were comparatively analyzed. Results FFA showed that all the eyes appear as delayed filling of the optic disc in early stage and hyperfluorescence leakage of the optic disc in late stage,besides hyperfluorescence presented to macular area in 24 eyes. OCT showed that optic papilla swelling and physiological depression narrow or nearly disappearance, neuroepithelial layer thickening or neuroepithelial layer eminence and subretinal fluidity area opaca between optic disc and macula. There were 14 eyes with normal physiological depression and 22 eyes with small physiological depression or non- physiological depression in control group. Half month after onset, the neuroepithelial layer thickness of macula fovea, the maximum thickness of neuroepithelial layer between optic disc and macula, and the average retinal nerve fiber layer ( RNFL) thickness in NAION group were higher than those in the control group,the difference were statistically significant (F=6. 51,26. 12,75. 49; P<0. 05). Two months after onset,the maximum thickness of neuroepithelial layer between optic disc and macula, the average RNFL thickness, and the RNFL thickness of temporal optic disc in NAION group were significant thinner, but the elevated height of the optic disc in NAION group were near those of the control group. Three months after onset, the average RNFL thickness and the RNFL thickness of temporal optic disc in NAION group decreased continually, they were lower than those of the control group, the difference were statistically significan(F=75. 49,37. 92;P<0. 05). Visual field showed that inferior defect were found in 21 eyes (45%). With progress, the superior RNFL thickness obviously decreased, coincidence with appearance of visual field. It indicate that the superior optic atrophy serious. Visual acuity had significant negative correlation with the neuroepithelial layer thickness of macula fovea, the neuroepithelial layer maximum thickness between optic disc and macula, the average RNFL thickness, the RNFL thickness of temporal optic disc(r=-0.394,-0. 424,-0. 412,-0. 464; P<0. 05). Conclusions FFA showes that hyperfluorescence leakage appearanced in part macula. OCT showes that RNFL becomes thinner as the disease duration increases. The results of OCT and visual field examinaion in the configuration of optic disc and changes of RNFL are accordant. Key words: Optic neuropathy,ischemic/diagnosis; Fluorescein angiography/utilization; Tomography,optical coherence/utilization; Perimetry/utilization