Objective To observe the relationship between shallow optic cup，small disc and occurrence in patients with nonarteritic anterior ischemic optic neuropathy (NAION).Methods Ninetysix patients（96 diseased eyes）who accorded with the diagnosis criteria for NAION，with duration ge; three months and optic disc edema in paracmasis were selected. The fellow eyes of 96 NAION patients and 80 normal eyes were selected in our study. The horizontal and vertical disc and cup diameters，optic cup depth, and peripapillary retinal nerve fiber layer (RNFL) thickness were measured by quot;crossquot; and quot;ringquot; scan of optical coherence tomography (OCT，Humphrey 2000，German Carl Zeiss Company) inspection system. The cup depth were classified four grades by cup shape according to OCT images：GradeⅠ，bottom of optic cup above the anterior plane of peripapillary neuroepithelial layer（PNL）；GradeⅡ，bottom of optic cup above the plane of PNL；Grade Ⅲ，bottom of optic cup between the plane of PNL and choroidal pigment epithelium；Grade Ⅳ，bottom of optic cup under the plane of choroidal pigment epithelium connection. The grades of optic cup and value in three groups were statistically analyzed. The follow up ranged from six months to three years.Results The disc diameter in horizontal scanning of diseased eyes，fellow eyes and normal eyes were (1.29plusmn;0.19), (1.32plusmn;0.17), (1.40plusmn;0.15) mm，and diameters in vertical scanning were (1.52plusmn;0.14), (1.49plusmn;0.17), (1.60plusmn;0.22) mm, respectively. Compared the diseased eyes and fellow eyes with normal eyes，the difference were statistically significant in horizontal scanning (t=4.291,3.315; P＜0.05) and in vertical scanning (t=2.812, 3.654; P＜0.05). Compared the diseased eyes with fellow eyes，the difference of average diameter were not statistically significant in horizontal and vertical scanning (t=1.153,1.335; P＞0.05). Of the diseased eyes，GradeⅠoptic cup in 36 eyes（37.50），Grade Ⅱ-Ⅲoptic cup in 52 eyes（54.17%），Grade Ⅳoptic cup in eight eyes（8.33%），and GradeⅠ-Ⅲ optic cup in 88 eyes（91.67%）were found. Of the fellow eyes，GradeⅠoptic cup in 18 eyes（18.75%），Grade Ⅱ-Ⅲoptic cup in 69 eyes（71.88%），Grade Ⅳoptic cup in nine eyes（9.34%），and GradeⅠ-Ⅲ optic cup in 87 eyes（9066%）were found. Compared the average RNFL thickness of diseased eyes with the fellow eyes and normal eyes，the differences were statistically significant in temporal, upper, nasal, lower quadrant(t=12.862，10.147，15.046，8.180，12.859，9.562，12.174，8.632；P＜0.001). Compared the average RNFL thickness of the fellow eyes and normal eyes，the differences were not statistically significant in all quadrants（t=1.040，1.576，1.062，1.192；P＞0.05）. During the followup，eight eyes with recurrence which optic cup were GradeⅠand Ⅱin diseased eyes；44 eyes（45.8%）occurred NAION. Correlation analysis showed that there was negative correlation between incidence of fellow eye and optic cup depth(t=-0.757, P=0.000). Conclusion Optic cup and disk in NAION patients are smaller than that in the normal，the anatomical characteristics of shallow cup and small disc was one of the NAION pathogenesis.
Objectives To evaluate the risk factors of nonarteritic a nterior ischemic optic neuropathy（NAION）in a population of China and to provide theory basis for clinical decision. Methods Demographic features and clinical data of NAION were recorded. Cerebral infarction (CI) patients were also collected as control group. Systemic evaluations including whole blood chemical test, brain MRI, carotid artery ultrasound and fundus photography were perfor med in NAION and CI patients. The fundus photography and cup/disk ratio were als o acquired in a healthy controlgroup with matched age and gender. Statistical a nalysis was done by SPSS11.5 software. Results Thirtyeight N AION patients and 40 CI patients with intact data were included. Fundus photography and cup/disk ratio were acquired in 41 healthy individuals. No statistically significant difference regard to incidences of diabetes, male gender and lipid metabolic abnormalities was found between NAION and CI patients (Pgt;0.05). H ypertension, clinical and subclinical cerebral vascular disease and carotid ar tery stenosis were statistically more commonin CI patients than in NAION patien ts (Plt;0.01, 0.05). Cup/disk ratio was statistically significant smaller in NAION than in CI patients while no statistical difference (Pgt;0.05) was fo und between the CI group and healthy individuals. Conclusions NAION shared similar risk factors with cerebral infarction, but exposure of these risk factors was different between NAION and cerebral infarction. Hypertension , cerebral vascular disease and carotid artery stenosis were more common in cere bral infarction while diabetes, male gender and lipid metabolic abnormalities were similar. Small cup/disk ratio was an independent and the most important risk factor for NAION. (Chin J Ocul Fundus Dis,2008,24:86-89)