Search

Purpose The pathophysiology of nonarteritic anterior ischemic optic neuropathy (NAION) is not completely understood. Studies of the retinal vasculature phenotype in patients with NAION could help us to understand vascular abnormalities associated with the disease. Design Retrospective case series with matched control subjects. Methods Study population: 57 patients with NAION and 57 control subjects matched to NAION patients for sex, age, systemic hypertension, diabetes, and obstructive sleep apnea syndrome between September 2007 and July 2017. Main Outcome Measures All patients and control subjects underwent a complete ocular examination and 45° funduscopic color photographs. The widths of the 6 largest arteries in zone B (between 0.5 and 1 optic disc diameter from the optic disc), summarized by the central retinal artery equivalent (CRAE), the widths of the 6 largest veins in zone B, summarized by the central retinal vein equivalent (CRVE), the arteriole to venule ratio, tortuosity, and fractal dimension were measured on the 2 groups using Vessel Assessment and Measurement Platform for Images of the Retina, a software tool for efficient semiautomatic quantification of the retinal vasculature morphology in fundus camera images. The Wilcoxon signed-rank test and MacNemar χ2 test for paired sample and generalized estimating equations for modeling the Vessel Assessment and Measurement Platform for Images of the Retina parameters as dependent variables were used. Results CRVE and fractal dimension (D0a) were significantly higher in the NAION group when compared with the control group, whereas the arteriole to venule ratio and vascular tortuosity were significantly lower. Compared with control subjects, acute NAION yielded an increased CRAE value (174 ± 33 vs 160 ± 13 μm) while resolution NAION yielded a decreased CRAE value (152 ± 12 vs 156 ± 33 μm). Acute NAION yielded an increased CRVE value (244 ± 35 vs 210 ± 21 μm) while resolution NAION yielded an unchanged CRVE value. We found no difference between groups for age, refraction, optic disc diameter, CRAE, or fractal dimension. Conclusions Retinal vascular parameters were different in our sample between NAION and control patients, especially at the acute stage of the disease. Our results suggest a normalization of the same parameters at the resolution stage.

To determine whether the development of nonarteritic anterior ischemic optic neuropathy (NAION) is increased after receiving cataract surgery in a large general population.Nationwide, population-based, retrospective cohort study.Setting: A 12-year nationwide, population-based, retrospective cohort study including 1,025,340 beneficiaries in the 2002-2013 Korean National Health Insurance Service database.We identified 40,356 patients who had undergone cataract surgery and matched non-cataract surgery controls (1:2) using estimated propensity scores in reference to age, sex, demographics, comorbidities, and co-medications.Kaplan-Meier curves and Cox proportional hazard models were generated to determine the risk of developing NAION in the cataract surgery group compared to the non-cataract surgery group.Effect (hazard ratio [HR]) of cataract surgery on NAION development.The 10-year incidence probability of NAION was 0.70% (95% confidence interval [CI], 0.55%-0.86%) in the cataract surgery group and 0.27% (95% CI, 0.25%-0.29%) in the non-cataract surgery group (P.0001, log-rank test). The cataract surgery group had an increased risk of developing NAION compared to the non-cataract surgery group (HR = 1.80; 95% CIs, 1.46-2.21) even after adjusting for demographics, comorbidities, Charlson comorbidity index, and co-medications.Our results suggest that patients undergoing cataract surgery have an increased risk of NAION.

Purpose To determine whether nonarteritic ischemic optic neuropathy (NAION) raises the risk of subsequent stroke in the general population. Design Population-based, retrospective cohort study. Methods Setting : Nationwide, population-based, retrospective cohort study. Patients : Of 1 025 340 beneficiaries in the National Health Insurance Service–National Sample Cohort database (2002-2013), we included 400 952 eligible individuals in the analysis. Observations : To determine the effect of incident NAION on the occurrence of subsequent stroke, we used time-varying covariate Cox regression models. Model 1 included only incident NAION as a time-varying covariate. Model 2 included Model 1 and defined demographics. Model 3 included Model 2, comorbidity, co-medication, and Charlson index score. Main Outcome Measures : Effect (hazard ratio [HR]) of NAION on stroke development. Results Of 400 952 eligible individuals, 1125 patients developed NAION and 16 998 patients suffered from stroke. NAION was not associated with an increased risk of subsequent stroke in Model 1, with HR of 1.31 (95% confidence interval [CI], 0.89-1.92). This was consistent, after adjusting for demographics and/or confounding factors, in Model 2 (HR = 1.19, 95% CI, 0.81-1.75) and Model 3 (HR = 1.10, 95% CI, 0.75-1.62). Conclusions Our results suggest that NAION per se is not associated with a subsequent risk of stroke in the general population.

PURPOSE: To determine if there is an increased incidence rate of post-cataract surgery (pcs) anterior ischemic optic neuropathy (AION) compared to spontaneous AION (sAION). DESIGN: Retrospective, population-based cohort. METHODS: Patients diagnosed with AION from January 1, 1990 through December 31, 2016 while residing in Olmsted County, Minnesota. Patients with cataract surgery preceding AION were included in the pcsAION cohort defined in two ways: AION within two months and AION within one year of cataract surgery. The incidence rates of pcsAION and sAION were compared using Poisson regression models. RESULTS: During the study period, 102 residents developed AION. The median age was 65 years (range, 40-90 years), 44 (43.1%) were female. Twenty of 102 (19.6%) patients had previous cataract surgery, of which 2 and 9 developed AION within 2 months and 1 year of surgery, respectively. The annual incidence rate of pcsAION within two months of surgery (8.6 per 100,000) was not significantly greater than the annual incidence rate of sAION (6.9 per 100,000; p=0.78). However, the annual incidence rate of pcsAION within one year of surgery (38.9 per 100,000) was significantly higher than the incidence rate of sAION (6.5 per 100,000; p

Purpose To use spectral-domain optical coherence tomography (SD-OCT) to assess whether epipapillary vitreous traction from evolving posterior vitreous detachment (PVD) is mechanistically involved in the pathogenesis of nonarteritic anterior ischemic optic neuropathy (NAION). Design Retrospective cohort study. Methods Setting : Single academic center. Patient or Study Population : Eighty eyes in 74 subjects presenting within 2 weeks of symptom onset of NAION. Intervention or Observation Procedures : SD-OCT imaging of the optic nerve head, macula, and peripapillary retinal nerve fiber layer (pRNFL) were reviewed for PVD and vitreopapillary traction (VPT). Main Outcome Measures : Prevalence and incidence of PVD and VPT, logMAR best-corrected visual acuity (BCVA), mean deviation (MD) on automated perimetry, and pRNFL thickness at presentation and final follow-up. Results The co-prevalence of PVD at the time of acute presentation for NAION was 30% (n = 24/80). This was similar to the prevalence of PVD in contralateral uninvolved eyes (34.5%, n = 19/55). In 8 NAION eyes, PVD had been documented prior to the onset of NAION. No eyes had SD-OCT evidence of VPT on presentation or final follow-up. Only 5 eyes developed a PVD following the development of NAION, and this typically occurred months after resolution of optic disc edema. When comparing eyes with PVD and without PVD, there was no significant difference in BCVA, MD, and pRNFL thickness at baseline, final follow-up, or the change from baseline to final follow-up (all P > .10). Conclusions VPT was not mechanistically related to the development of classic NAION. Preexisting PVD did not preclude the future development of NAION. The co-prevalence of PVD with acute NAION had no impact on final visual outcome.

Purpose To investigate the risk of acute tubular necrosis (ATN) in patients with nonarteritic anterior ischemic optic neuropathy (NAION). Design Population-based cohort study. Methods This is a nationwide, population-based, retrospective study using data from the Korean national health claims database from 2011 through 2015. Patients with NAION and randomly selected control subjects from the entire population of South Korea were enrolled. A log-rank analysis was used to evaluate a risk of ATN in the group of patients with NAION (study group) compared to an age-, sex-, and comorbidities-matched control group. Comorbidities included diabetes, chronic lung disease, congestive heart failure, ischemic stroke, anemia, septic shock, and antibiotic use. A Cox proportional hazards regression analysis with cluster effect was performed to calculate the adjusted hazard ratio (aHR) of ATN. Results A total of 22 498 patients were included in the study group and 31 475 in the control group. Twenty-six cases of ATN were observed in the NAION group and 11 in the control group. The study group was more likely to have ATN (aHR = 2.55, 95% confidence interval: 1.50–5.91, P = .029) than the control group. Among the 26 newly developed cases of ATN, 13 (50%) occurred in the 0–6 months before/after NAION. Conclusions We demonstrated that subjects with NAION are at increased risk of ATN and suggested a possible common mechanistic link between the 2 diseases. These results provide significant evidence that proper patient education and further systemic evaluation of the possibility of ATN development are required in patients with NAION.

Purpose To reassess the prevalence and incidence of post–cataract surgery optic neuropathy (PCSON) in the modern era. Design Retrospective cohort study. Methods Setting: Single-center tertiary care practice. Study Population: All patients with a diagnosis of nonarteritic anterior ischemic optic neuropathy (NAION) seen in the Wilmer Eye Network system between January 1, 2010 and December 31, 2014 were included. Inclusion was based on the following: (1) a history of an acute unilateral decrease in vision, (2) a visual field defect consistent with NAION, (3) a relative afferent pupillary defect, (4) observed optic disc swelling, and (5) no other etiology being found. Main Outcome Measures: The prevalence and incidence of PCSON and the temporal association between surgery and onset of PCSON. The secondary outcome was the risk of PCSON in the fellow eye of patients with prior unilateral spontaneous NAION. Results One hundred eighty-eight patients had developed NAION during the study period. Of these, 18 (9.6%) had undergone cataract surgery (CS) during the year prior to developing NAION. There was no significant temporal pattern associated with the distribution of NAION cases ( P = .28). The incidence of PCSON in patients who had noncomplex CS was 10.9 cases per 100 000 (95% CI, 1.3, 39.4). Conclusions Our data indicate that both the prevalence and incidence of NAION after modern CS are comparable to those of the general population and that there is no significant temporal relationship between modern CS and the subsequent development of NAION in the operated eye. Thus, although this study has inherent biases owing to its retrospective nature, concern regarding an increased risk of PCSON in the fellow eye in patients who have experienced it or spontaneous NAION in 1 eye may be unwarranted.

To compare macular vasculature in patients with primary open-angle glaucoma (POAG) and atrophic nonarteritic anterior ischemic optic neuropathy (NAION).Prospective, cross-sectional study.Thirty-seven eyes with moderate and advanced POAG, 19 eyes with atrophic NAION, and 40 eyes of normal subjects were imaged using optical coherence tomography angiography (OCT-A). Macular ganglion cell complex (GCC) and peripapillary retinal nerve fiber layer (RNFL) thicknesses were measured in addition to macular superficial and deep vasculature after projection removal using custom software.Linear models showed that while averaged peripapillary RNFL and macular GCC were not different between NAION and POAG eyes, both were significantly thinner than control eyes. Whole image macular superficial vessel density was significantly lower in NAION and glaucoma eyes (P = .003 and.001, respectively) than in normal eyes, with lower vessel density in glaucoma than in NAION eyes (P = .01). Whole image and parafoveal deep macular vessels in glaucoma eyes (21.0%±8.7%, 24.4%±9.6%) were significantly lower than in control eyes (27.4%±8.6%, 31.9%±10.6%) (P = .01 and P = .01, respectively). No significant differences in deep vessels were observed between NAION and control eyes. Glaucomatous eyes had lower temporal and inferior parafoveal deep vasculature values than NAION eyes (P = .007 and .03, respectively).In NAION and POAG with similar RNFL and macular damage, macular OCT-A shows less involvement of superficial and deep vascular plexus in NAION in contrast to POAG, which might show a primary vascular insult in addition to secondary vascular damage due to ganglion cell damage.

Purpose To investigate the incidence and prevalence of nonarteritic anterior ischemic optic neuropathy (NAION), and to extrapolate the risk of cerebrovascular events following NAION. Design Retrospective cohort study. Methods We identified NAION patients first, and then looked for the diagnosis of stroke after the diagnosis of NAION. Setting: The study group was composed of patients diagnosed with NAION seeking ambulatory care from 2000 to 2011. The control group was extracted from a database by randomly selecting 2 patients for every NAION patient, matched by age and sex. Main Outcome Measures: Cox proportional hazards regression analysis was performed to calculate adjusted hazard ratio (aHR) of stroke for the 2 groups. Subgroup analysis of subjects with or without comorbidities was also investigated. Results Four hundred and fourteen patients were included in the study group and 789 in the control group. The mean follow-up period was 5.9 years. The incidence of NAION was 3.72/100 000 person-years in Taiwan, and the prevalence of NAION was 48.18/100 000 persons. The study group was more likely to have ischemic stroke (aHR = 2.03, P = .003), but not hemorrhagic stroke (aHR = 1.24, P = .696), than the control group. Among the subgroup with comorbidities, the risk of ischemic stroke among the subjects with NAION was 3.35 times higher than those without NAION (95% confidence interval: 1.67, 6.70). Conclusions Patients with NAION have an increased risk of ischemic stroke. Physicians should refer all patients with NAION for systemic survey of vasculopathy and control of modifiable risk factors to prevent irreversible neurological sequelae.

Purpose To measure and compare the cytokine concentrations in the aqueous humor of patients with acute nonarteritic anterior ischemic optic neuropathy (NAION) and normal age-related cataract controls. Design Prospective, comparative observational study. Methods Aqueous humor samples were obtained in 10 patients with acute NAION (within 14 days of symptom onset) and 15 control patients with age-related cataract. The levels of 6 cytokines—vascular endothelial growth factor (VEGF), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-2, IL-6, and IL-8—were determined using a multiplex bead immunoassay. The clinical characteristics of patients were also collected for correlation analysis. Results The mean concentration of VEGF (94.1 ± 40.4 pg/mL) was significantly higher in the NAION group compared to the cataract controls (52.2 ± 20.8 pg/mL; P = .010) and the mean concentration of IL-2 (5.56 ± 1.27 pg/mL) was significantly lower in the NAION group than in the cataract controls (16.6 ± 14.0 pg/mL; P = .002). There were no differences in the concentration of TNF-α, IL-1β, IL-6, and IL-8. There was a strong negative correlation between the VEGF concentration and the peripapillary retinal nerve fiber layer (RNFL) thickness at presentation (r = −0.657, P = .055). There was no significant correlation between the RNFL thickness and any other cytokines, the mean deviation on 24-2 Humphrey visual fields, or the duration of vision loss. Conclusions Acute NAION is associated with higher VEGF and lower IL-2 concentrations without a change in other inflammatory cytokines. This has implications for future therapeutic interventions and diagnostic testing in patients with this acute optic neuropathy.

Purpose To report three cases of nonarteritic anterior ischemic optic neuropathy (NAION) that occurred in patients with sleep apnea syndrome (SAS) while being treated with continuous positive airway pressure (CPAP). Design A prospective, noncomparative case series. Methods Prospective review of 108 patients with NAION diagnosed between 2002 and 2003 to identify any patients who developed NAION while being treated for SAS with CPAP. Results One patient had bilateral sequential NAION and two patients had unilateral NAION despite treatment with CPAP for SAS. All the patients were being treated with CPAP for a period ranging from 4 months to 6 years before the onset of NAION. Conclusions In this series, CPAP did not prevent the development of NAION in SAS patients. Larger observational studies are needed to study the benefit of CPAP in preventing NAION in patients with SAS.

Purpose To examine choroidal thickness in nonarteritic anterior ischemic optic neuropathy (AION). Design Retrospective case control study. Methods In the eye clinic of the University Medical Center in Mannheim, Germany, we studied a group that consisted of patients with nonarteritic AION and a control group that consisted of individuals with normal fundus. Choroidal thickness was measured by the enhanced-depth imaging of spectral-domain optical coherence tomography. The main outcome measure was choroidal thickness. Results The study group consisted of 20 patients: 11 patients with acute nonarteritic AION and an unaffected contralateral eye and 9 patients with acute unilateral nonarteritic AION and previously nonarteritic AION in the contralateral eye. The control group consisted of 58 patients (58 eyes). In multivariate analysis, thinner subfoveal choroidal thickness was associated with the diagnosis of nonarteritic AION ( P = 0.001; regression coefficient B, −55.1), after adjusting for age ( P P = 0.20). Similarly, unaffected eyes contralateral to eyes with acute nonarteritic AION as compared to control eyes showed thinner subfoveal choroidal thickness ( P = 0.037) after adjusting for age ( P = 0.001) and refractive error ( P = 0.06). In a reverse manner, nonarteritic AION was associated with thinner subfoveal choroidal thickness ( P = 0.007) after adjusting for age, optic disc diameter, gender, and refractive error. Conclusions Eyes affected by nonarteritic AION and unaffected contralateral eyes showed significantly thinner macular choroids than eyes of a control group after adjusting ocular and systemic parameters. A thin choroid may be added to the diagnostic features of nonarteritic AION. Future studies may examine the pathophysiologic meaning of the finding.

PURPOSE: To investigate the effects of topical beta-blocker eyedrops on nocturnal arterial hypotension and heart rate and on visual field deterioration. METHODS: We prospectively investigated 275 white patients, 161 with glaucomatous optic neuropathy and 114 with nonarteritic anterior ischemic optic neuropathy, by 24-hour ambulatory blood pressure monitoring and diurnal curve of intraocular pressure, in addition to detailed ophthalmic evaluation. Of the patients with glaucomatous optic neuropathy, 131 had normal-tension glaucoma and 30 had primary open-angle glaucoma. Of the 275 patients, 114 were using topical beta-blocker eyedrops twice daily (76 with normal-tension glaucoma, 26 with primary open-angle glaucoma, and 12 with anterior ischemic optic neuropathy). RESULTS: Hourly average blood pressure data analyses showed overall a drop in blood pressure as well as heart rate during sleep, and a significantly greater drop in mean diastolic blood pressure ( P = .009) at night in normal-tension glaucoma than in anterior ischemic optic neuropathy. Also, patients using beta-blocker eyedrops experienced a significantly greater percentage drop in diastolic blood pressure at night ( P = .028), lower minimum nighttime diastolic blood pressure ( P = .072), and lower minimum nighttime heart rate ( P = .002) than did those not using them. In normal-tension glaucoma, eyes receiving beta-blocker eyedrops showed visual field progression significantly ( P = .0003) more often than those not receiving beta-blockers. CONCLUSIONS: The findings of our studies, as well as those of others, suggest that any factor that increases nocturnal arterial hypotension is a potential risk factor in vulnerable individuals with glaucomatous optic neuropathy or anterior ischemic optic neuropathy. The present study suggests that the use of beta-blocker eyedrops, by aggravating nocturnal arterial hypotension and reducing the heart rate, may be a potential risk factor in susceptible individuals.

We investigated, in nonarteritic anterior ischemic optic neuropathy, the prevalence of various systemic diseases before or at its onset and the incidence of subsequent morbidity and mortality.We investigated prospectively the presence of systemic diseases before or at the onset of nonarteritic anterior ischemic optic neuropathy in 406 patients. The information was obtained by complete medical history and physical examination. The prevalence rates of systemic diseases in young, middle-aged, and elderly groups were compared with those in the general population. We also analyzed the influence of systemic diseases on subsequent morbidity and mortality.Compared with the prevalences reported in the general population, our patients in each of the three age groups showed a significantly higher prevalence of arterial hypertension (Por = .02), diabetes mellitus (P.01), and gastrointestinal ulcer (Por = .02). Also, middle-aged and elderly patients showed a significantly higher prevalence of ischemic heart disease (P.01) and thyroid disease (P.01). Middle-aged patients had significantly higher rates of chronic obstructive pulmonary disease and cerebrovascular disease (Por = .01). After onset of anterior ischemic optic neuropathy, patients with both arterial hypertension and diabetes mellitus had a significantly higher incidence of cerebrovascular disease (P.01).Nonarteritic anterior ischemic optic neuropathy is a multifactorial disease in which some systemic diseases may act as predisposing factors and others as precipitating factors. Patients with anterior ischemic optic neuropathy show no significant increase in mortality, but those with both arterial hypertension and diabetes mellitus have significantly (P.01) increased incidence of cerebrovascular disease.

We measured 24-hour ambulatory blood pressure monitoring and diurnal curve of the intraocular pressure in 166 white patients with anterior ischemic optic neuropathy, normal-tension glaucoma, primary open-angle glaucoma, and other optic nerve head disorders. Hourly average blood pressure data analyses showed a significant (P.0001) decrease in mean systolic (26%) and diastolic (33%) blood pressure measurements at night. A significantly (P = .0028) lower nighttime mean diastolic blood pressure and a significantly (P = .0044) greater mean percentage decrease in diastolic blood pressure were noted in normal-tension glaucoma than in anterior ischemic optic neuropathy. Patients with arterial hypertension taking oral hypotensive therapy showed a significant association between progressive visual field deterioration and nocturnal hypotension, particularly in anterior ischemic optic neuropathy. Intraocular pressure showed no significant correlation with visual field deterioration in any of these conditions. Our findings suggest that nocturnal hypotension, in the presence of other vascular risk factors, may reduce the optic nerve head blood flow below a critical level, and thereby may play a role in the pathogenesis of anterior ischemic optic neuropathy and glaucomatous optic neuropathy; that is, nocturnal hypotension may be the final insult in a multifactorial situation. The same mechanisms may be true of a number of other ocular ischemic disorders. This finding opens a new dimension in the understanding and management of these visually disabling diseases.

Fundus fluorescein angiograms from 41 patients with nonarteritic anterior ischemic optic neuropathy of less than three weeks' duration were compared with those from 43 age-matched control subjects. Patients with disease showed statistically significant delay in both the onset and the time to completion of prelaminar optic disk filling. Neither onset nor completion of peripapillary choroidal filling were markedly delayed when compared with control subjects. Frequency of occurrence of delayed filling within peripapillary choroidal watershed zones was not increased in patients with disease. There was no consistent correlation by quadrant between optic disk filling delay, choroidal filling delay, optic disk swelling or hyperfluorescence, and visual field deficit. No trend for change in characteristics was found with increasing time interval from onset of symptoms to performance of angiography. Fluorescein angiography in nonarteritic anterior ischemic optic neuropathy demonstrates delayed optic disk filling without consistent relation to adjacent peripapillary choroidal filling delay or other disease findings.

Three patients with visual loss and normal fundi were discovered to have choroidal ischemia on fluorescein angiography. Each patient had a markedly increased Westergren erythrocyte sedimentation rate, but only one described symptoms of polymyalgia rheumatica, neck pain, and jaw claudication. Biopsy of the temporal artery confirmed giant cell arteritis in the two patients without constitutional symptoms. In one patient, typical anterior ischemic optic neuropathy developed the following day, whereas in the other two, anterior ischemic optic neuropathy later occurred despite the prompt administration of intravenous high-dose corticosteroids. Choroidal ischemia may be the first sign of giant cell arteritis in elderly patients with visual loss. Early diagnosis and treatment are mandatory in an attempt to forestall the development of anterior or posterior ischemic optic neuropathy, or central retinal artery occlusion in the affected or fellow eye.

PURPOSE: To report a case of anterior ischemic optic neuropathy after a trans-Atlantic airplane journey. DESIGN: An observational case report. METHODS: A 48-year-old healthy man presented with severe visual loss in his left eye within 12 hours after a 15-hour-long trans-Atlantic airplane flight. The patient underwent slit-lamp examination, funduscopy, fluorescein angiography, automated perimetry, and various blood examinations. RESULTS: Visual acuity was LE: 20/30, and a mild left eye relative afferent pupillary defect was noted. Funduscopic evaluation revealed an edematous optic disk in the left eye with a para-diskal retinal hemorrhage. Fluorescein angiography revealed a leaking optic disk, and perimetry showed an inferior hemi-field scotoma. Anterior ischemic optic neuropathy was diagnosed. CONCLUSION: Prolonged airplane travel may compromise vision either by a thromboembolic mechanism caused by prolonged immobilization or by a vasospasm mechanism induced by the low oxygen pressure during the flight.

First proposed by De Wecker! in 1872 as a treatment for neuroretinitis, optic nerve sheath decompression (or fenestration) is an operation that has caused much controversy. This surgical therapy was not seriously considered until Davidson" and Smith, Hoyt, and Newton" reintroduced it in 1969 as an alternative therapy for chronic disk edema. Over the next 19 years, however, only about 60 cases of optic nerve sheath decompression were described in the literature.v" This operation was not widely accepted until 1988, when Brourrnan, Spoor, and Ramocki.? Sergott, Savino, and Bosley." and Corbett and associates" simultaneously published their series of cases for which they used optic nerve sheath decompression as a treatment for pseudotumor cerebri. Keltner" stated the operation had merit and recommended that it be performed soon after failure of medical therapy for pseudotumor cerebri. Now, as optic nerve sheath decompression has finally become accepted as an effective and safe surgical treatment to limit visual loss in pseudotumor cerebri. great controversy surrounds its use as a treatment for anterior ischemic optic neuropathy. In 1989, Sergott and associates" suggested that optic nerve sheath decompression might improve the visual course in the progressive form of anterior ischemic optic neuropathy, a variant of anterior ischemic optic neuropathy that is characterized by progressive deterioration of visual function over several weeks." The relatively prolonged cadence of progressive anterior ischemic optic neuropathy suggested that surgical intervention might be of benefit. Sergott and associates'" used optic nerve sheath decompression in 14 eyes of 14 patients with progressive anterior ischemic optic neuropathy. They described visual improvement in 12 of these 14 eyes, compared with no improvement in 12 untreated eyes that were similarly afflicted. Other investi

PURPOSE: To report anterior ischemic optic neuropathy associated with systemic hypotension in a patient undergoing continuous ambulatory peritoneal dialysis. METHODS: Case report. A 58-year-old man undergoing continuous ambulatory peritoneal dialysis developed painless blurred vision in both eyes and bilateral optic disk swelling with an altitudinal field defect in the left eye. Twenty-four-hour ambulatory blood pressure monitoring was requested in addition to other routine investigations. RESULTS: Routine blood pressure measurement in the clinic was 130/86 mm Hg, but ambulatory blood pressure monitoring demonstrated pronounced early morning hypotension with individual readings as low as 91/41 mm Hg. CONCLUSIONS: Renal dialysis can render patients hypotensive, and this may be associated with anterior ischemic optic neuropathy. The overnight drop in blood pressure may not be appreciated with routine blood pressure measurement. Therefore, 24-hour ambulatory blood pressure monitoring should be considered when investigating patients with suspected anterior ischemic optic neuropathy who are undergoing renal replacement.

PURPOSE: To report clinical features of amiodarone-induced optic neuropathy and outline the differentiation of amiodarone optic neuropathy from nonarteritic anterior ischemic optic neuropathy. METHOD: We reviewed data from 73 patients reported to have developed an optic neuropathy while taking amiodarone. RESULTS: Amiodarone optic neuropathy is characterized by an insidious onset, slow progression, bilateral visual loss, and protracted disk swelling that tends to stabilize within several months of discontinuing the medication. Nonarteritic ischemic optic neuropathy is characterized by acute, unilateral visual loss that is usually complete at onset, with resolution of disk edema over several weeks. CONCLUSION: Unique clinical features of amiodarone-induced optic neuropathy may help clinicians diagnose and distinguish between amiodarone-induced optic neuropathy and nonarteritic anterior ischemic optic neuropathy.

PURPOSE: To report a case of sequential anterior ischemic optic neuropathy temporally related to the sequential use of a decongestant nasal spray. METHODS: A 43-year-old woman was evaluated for sequential bilateral vision loss following the use of oxymetazoline nasal spray. RESULTS: Thorough investigation of possible etiologies causing the bilateral anterior ischemic optic neuropathy was negative. Our patient had several predisposing risk factors for ischemic optic neuropathy, including diabetes mellitus, hypertension, and crowded optic nerve heads. Before each acute optic neuropathy, the patient used two to three puffs of oxymetazoline nasal spray. CONCLUSION: Decongestants have been associated with ischemic and hemorrhagic vascular events. Vasoconstriction secondary to oxymetazoline use may precipitate anterior ischemic optic neuropathy.

Purpose To characterize anterior ischemic optic neuropathy (AION) in patients younger than 50 years. Design Retrospective study. Methods Records of all AION patients seen between 1989 and 2006 were reviewed. Patients younger than 50 years when initial visual loss occurred were included. Results Of 727 consecutive patients with AION, 169 (23%) were younger than 50 years (median, 43 years; range, 13 to 49 years; 58% men; 93% White). Involvement was unilateral in 59% of patients and bilateral in 41%. At least one cardiovascular risk factor was found in 74% of patients. Hypercoagulable states and vasculitis were found in 8%. An underlying small or anomalous optic disk was found in 92% of eyes (210/230). Isolated disk anomalies (without systemic risk factors) were present in 26% of eyes. Final visual acuities were 20/40 or better in 64% of eyes and 20/200 or worse in 22%. Among patients with bilateral involvement, final visual acuity was similar in the two eyes in 70% of patients. Anemia and type I diabetes were associated significantly with fellow eye involvement. Recurrent AION in the same eye occurred in 6% of patients. Conclusions AION in younger patients is not uncommon and represents 23% of AION patients in a tertiary neuro-ophthalmic service. Except for giant cell arteritis, ocular and systemic risk factors and associated disorders are similar to those described in older AION patients. Younger AION patients have better visual acuity outcomes but a higher risk of fellow eye involvement than older AION patients.

Purpose To evaluate correlations between retinal nerve fiber layer (RNFL) thickness with visual field (VF) sensitivities in eyes with nonartertic anterior ischemic optic neuropathy (NAION). Design Case-control study in an academic, institutional setting. Methods One eye from 21 patients with NAION and 32 healthy participants were included in this prospective study. Humphrey visual field (HVF) sensitivities were obtained from standard achromatic HVF test (24-2 SITA). RNFL was measured with scanning laser polarimetry (SLP, GDx-VCC) and optical coherence tomography (OCT, StratusOCT). Correlations were evaluated between RNFL and sensitivities from global, hemifields, and regional locations of the VF pertinent to the RNFL distribution. A total of 15 NAION eyes had inferior altitudinal HVF defects, and their global and regional RNFL was compared with that of control eyes. The main outcome measure was correlation between HVF sensitivities and RNFL. Results Correlations of global, hemifield, and sectorial HVF sensitivities with RNFL were greater when RNFL was measured with OCT than with SLP, except for nasal and inferonasal sectors. RNFL thickness was far lower in the hemiretinas corresponding to the relative unaffected hemifield in eyes with altitudinal VF defect compared with controls. Conclusions In patients with NAION, RNFL measured by OCT provided better correlation to HVF changes than SLP did. Both instruments showed decreased RNFL in NAION eyes with altitudinal VF defects compared with control eyes, demonstrating loss of RNFL even in sectors of the optic disk that corresponded to relatively unaffected hemifield, suggesting greater damage beyond the extent estimated by VF methods.

We evaluated the effect of optic disk edema on spontaneous venous pulsations (SVP) in patients without elevated intracranial pressure (ICP).Prospective, cross-sectional comparison in an institutional setting.Twenty consecutive patients with unilateral optic disk edema due to anterior ischemic optic neuropathy (AION, n = 11) or optic neuritis (n = 9) were evaluated. The proportion of subjects with SVP in both eyes, the involved eye only, the uninvolved eye only, or neither eye was determined. Comparisons were made using the Exact McNemar Test.There was a significant difference in the proportion of uninvolved and involved eyes with SVP (60% [12/20] vs 5% [1/20], P.005). Spontaneous venous pulsations were present in the uninvolved eye of 12 patients and the nonedematous portion of the optic disk in 1 patient with segmental edema from AION.Optic disk edema may cause SVP cessation without ICP elevation.

PURPOSE: To examine the prevalence and incidence of second eye nonarteritic anterior ischemic optic neuropathy (NAION) and associated patient characteristics in patients enrolled in the Ischemic Optic Neuropathy Decompression Trial (IONDT) Follow-up Study. DESIGN: Randomized clinical trial with observational cohort. METHODS: Patients randomized to optic nerve sheath decompression surgery or careful follow-up had a diagnosis of acute unilateral NAION, visual acuity between 20/64 and light perception, and were aged 50 years or older. Eligible patients who declined randomization or whose visual acuity was better than 20/64 were not randomized but followed as part of an observational cohort. Follow-up examinations took place at 3, 6, 12, 18, and 24 months and annually thereafter. RESULTS: Four hundred eighteen patients were enrolled; 258 randomized and 160 observed. Previous NAION or other optic neuropathy was present in the fellow eye of 21.1% (88/418) of patients at baseline. Four patients developed optic neuropathy in the fellow eye at follow up that could not be conclusively diagnosed as NAION. New NAION in the fellow eye occurred in 14.7% (48/326) of patients at risk during a median follow up of 5.1 years. Randomized patients experienced a higher incidence (35/201; 17.4%) than nonrandomized patients (13/125; 10.4%). A history of diabetes and baseline visual acuity of 20/200 or worse in the study eye, but not age, sex, aspirin use, or smoking were significantly associated with new NAION in the fellow eye. Final fellow eye visual acuity was significantly worse in those patients with new fellow eye NAION whose baseline study eye visual acuity was 20/200 or worse. CONCLUSIONS: Follow-up data from the IONDT cohort provide evidence that the incidence of fellow eye NAION is lower than expected: new NAION was diagnosed in 14.7% of IONDT patients over approximately 5 years. Increased incidence is associated with poor baseline visual acuity in the study eye and diabetes, but not age, sex, smoking history, or aspirin use.

PURPOSE: To report the prevalence of recurrence of nonarteritic anterior ischemic optic neuropathy (NA-AION) in the same eye and possible contributing risk factors. DESIGN: Cohort study. METHODS: Setting: Institutional. STUDY POPULATION: The study includes 594 consecutive patients (829 eyes) with a diagnosis of NA-AION and follow-up of at least two months after the onset of NA-AION, examined in the Ocular Vascular Clinic since 1973. Simple progression of visual loss during an episode of NA-AION was not considered a fresh episode. INTERVENTION OR OBSERVATION PROCEDURES: Every patient had ophthalmic evaluation, including visual acuity, visual fields with a Goldmann perimeter, intraocular pressure, and slit lamp and ophthalmoscopic evaluation at initial visit and at each follow-up visit. The patients also had systemic evaluation; some patients had echocardiography (166 patients) and 24-hour ambulatory blood pressure (BP) monitoring—the latter was investigated in 80 patients (17 with and 63 without recurrence of NA-AION) who consented to participate in this study which was started in 1989. While optic disk edema was present, the patients were followed every 2 to 3 weeks. Once the optic disk edema resolved, they were followed up after 3 months, 6 months, and then at yearly intervals unless they had some new visual complaint. MAIN OUTCOME MEASURES: Prevalence of a fresh episode of NA-AION in the same eye, and comparison of ocular and systemic risk factors between patients with and without recurrence of NA-AION in the same eye. RESULTS: Of the 594 patients (829 eyes) in the study, recurrence of NA-AION in the same eye occurred in 45 patients (53 eyes) with a median follow-up of 3.1 years (range 2 months to 30.5 years) from the first onset of NA-AION. The Kaplan–Meier survival curve showed cumulative percentage of recurrence of NA-AION from first episode to second episode at three months 1.0%±0.4%(SE), at 6 months 2.7%±0.7%, at one year 4.1%±0.9%, and 2 years 5.8%±1.1%. There was no significant association between recurrence of NA-AION and the systemic conditions that were examined, except for nocturnal arterial hypotension. Overall patients with a recurrence of NA-AION had a significantly lower mean nighttime minimum diastolic BP ( P = .003) and greater mean percentage drop during sleep in diastolic BP ( P = .011) than those with no recurrence of NA-AION; all other measures of nocturnal hypotension were not significantly predictive. CONCLUSIONS: Recurrence of NA-AION in the same eye is uncommon (6.4%). Our study indicates that nocturnal diastolic arterial hypotension may be a risk factor; however, since this is a multifactorial disease, other so far unknown risk factors may also play a role. The role of various risk factors which may contribute to the recurrence of NA-AION is discussed.

PURPOSE: To report nonarteric anterior ischemic optic neuropathy (NAION) as an ocular manifestation in a woman with combined primary antiphospholipid syndrome and Factor V Leiden (FVL) mutation. METHODS: Case report of a middle-aged woman with hematological investigations confirming the diagnosis of both primary antiphospholipid syndrome and Factor V Leiden mutation, who presented with visual disturbance in her left eye. RESULTS: NAION was noted in her left eye. The patient was promptly treated with low molecular weight heparin, followed by warfarin, which resulted in the reversal of the ischemic optic neuropathy. CONCLUSIONS: Primary antiphospholipid syndrome and coexisting Factor V Leiden mutation should be considered in the differential diagnosis of NAION. Prompt treatment with anticoagulants can result in the reversal of the ischemic process.

PURPOSE: To report Nerve Fiber Analyzer (NFA/GDx; Laser Diagnostic Technologies, San Diego, California) measurements in a patient during the early phase of an anterior ischemic optic neuropathy. METHODS: Case report. A 58-year old man with acute anterior ischemic optic neuropathy had repeated NFA/GDx scans of the nerve fiber layer adjacent to the optic nerve head of the involved eye, as well as repeated HFA 30.2 (Humphrey Field Analyzer; Humphrey Systems, San Leandro, California) visual field examinations. RESULTS: At presentation (day 0), he had a normal superior nerve fiber bundle on the NFA/GDx, with a deep inferior hemifield scotoma. By day 21 and day 36, the superior nerve fiber bundle thinned on the NFA/GDx, whereas the scotoma remained practically unchanged. CONCLUSION: These findings suggest that after the onset of an anterior ischemic optic neuropathy, acute loss of axonal function results in scotoma, presumably from ischemia. This is followed by a gradual disappearance of nerve fiber tissue, as measured with the NFA/GDx, within several weeks.

PURPOSE: To report the development of a bilateral ocular ischemic syndrome despite corticosteroid treatment in a patient with giant cell arteritis. METHOD: Case report. RESULTS: Despite receiving high-dose intravenous methylprednisolone and oral prednisone for biopsy-proven giant cell arteritis that presented as a severe anterior ischemic optic neuropathy in the right eye, a patient developed progressive ocular ischemia in that eye as well as an ocular ischemic syndrome in the fellow eye. CONCLUSIONS: Some patients with giant cell arteritis, possibly patients with other underlying systemic vasculopathies, are refractory to what should be adequate treatment with systemic corticosteroids and may develop a bilateral ocular ischemic syndrome.

To investigate through the use of cerebral Doppler technology whether emboli are a more common cause of nonarteritic anterior ischemic optic neuropathy (NAION) than previously recognized.Eleven patients with a recent (121 days) history of nonarteritic anterior ischemic optic neuropathy and 10 age-matched controls (event121 days) were examined using a Nicolet Pioneer 2020 transcranial Doppler (TCD) unit with a 2-MHz bilateral continuous monitoring capability. The right and left middle cerebral arteries were evaluated simultaneously for 30 minutes at a depth of 50 to 55 mm, and the number of emboli, blood flow velocities, and pulsatility indices were recorded. Data were stored by computer, and hard-copy color recordings were made.None of 11 patients with a recent history of NAION demonstrated microemboli by TCD examination. One patient in the control group who had a remote history of NAION had a microembolic event rate of 12 per hour (six over 30 minutes). This patient had a history of prosthetic cardiac valve replacement and was taking anticoagulation medication at the time of the examination.Our study did not reveal an increased incidence of embolic events in patients with NAION when they were examined in a transcranial Doppler study of the middle cerebral arteries. This study does not support embolism as a frequent cause of NAION.

Purpose To determine the benefit of aspirin in reducing the risk of nonarteritic anterior ischemic optic neuropathy in the fellow eye following its occurrence in the first eye. Methods A retrospective cohort study was conducted on 431 patients, 153 of whom were and 278 of whom were not prescribed aspirin following the development of unilateral nonarteritic anterior ischemic optic neuropathy. Results The 2-year cumulative probability of nonarteritic anterior ischemic optic neuropathy in the fellow eye was 7% in the aspirin group and 15% in the no-aspirin group, and 5-year cumulative probabilities were 17% and 20%, respectively. Compared with the no-aspirin group, the rate ratio for nonarteritic anterior ischemic optic neuropathy in the fellow eye in the aspirin-user group was 0.43 (95% confidence interval, 0.19 to 0.92) over the first 2 years and 0.68 (95% confidence interval, 0.36 to 1.26) over the 5-year period. The overall calculated 5-year risk was 19%; however, if none of the patients with incomplete follow-up developed nonarteritic anterior ischemic optic neuropathy in the fellow eye, then the 5-year risk would be about 12%. Conclusions The 5-year risk of nonarteritic anterior ischemic optic neuropathy occurring in the second eye is far lower than that reported by previous studies. Our results suggest a possible short-term but little or no long-term benefit to aspirin in reducing the risk of nonarteritic anterior ischemic optic neuropathy in the fellow eye. However, this finding must be viewed with caution because this study was not conducted prospectively with a controlled protocol.

Purpose Nonarteritic anterior ischemic optic neuropathy is the most common acute optic nerve disease of adults over age 50 years. This study determined the incidence of acute nonarteritic anterior ischemic optic neuropathy in the circumscribed population of Olmsted County, Minnesota. Methods This was a retrospective study of the incidence of acute nonarteritic anterior ischemic optic neuropathy between 1981 and 1990. The Rochester Epidemiology Project medical records linkage system facilitates identification of the medical records of virtually all Olmsted County residents with a given diagnosis. All cases of acute nonarteritic anterior ischemic optic neuropathy that fulfilled certain inclusion and exclusion criteria were identified. Results Twenty-two cases in 21 patients (11 men and 10 women) were recorded. The crude annual incidence rate was 10.3 per 100,000 individuals (95% confidence interval [CI] = 5.1 to 18.4). When adjusted to the age and sex distribution of the 1990 United States white population, the incidence rate was 10.2 per 100,000 (95% CI=6.5 to 15.6). At diagnosis, the median age was 72 years, mean visual acuity was 20/200 in the affected eye, and the most common visual field defect was an altitudinal deficit (10 cases). Conclusions Although results of this small study should be interpreted cautiously, extrapolation of our findings to the United States white population indicates that nearly 5,700 new cases of acute nonarteritic anterior ischemic optic neuropathy may be expected to occur each year in this group.

Purpose To evaluate the effectiveness of hyperbaric oxygen therapy in reducing optic nerve damage in acute nonarteritic anterior ischemic optic neuropathy. Methods Twenty-two eyes in 20 patients with acute nonarteritic anterior ischemic optic neuropathy were treated with hyperbaric oxygen (100% oxygen, 2.0 absolute atmospheres of pressure) in two 90-minute inhalation sessions per day for ten days. Changes in mean visual acuity and mean sensitivity loss were compared with those of 27 untreated control patients with acute nonarteritic anterior ischemic optic neuropathy, and proportions of patients with a change in acuity or mean sensitivity loss were compared with controls. Similar analysis was performed on subgroups based on time delay from symptom onset to therapy. Results Mean values for visual acuity were increased at final examination in both groups; although the increase was greater in controls, the difference was not statistically significant. Mean visual field sensitivity loss was minimally increased; although the increase was smaller in controls, the difference between groups was not significant. There was no significant difference between groups in proportions of patients with change in acuity score or mean sensitivity loss. Stratification by time delay to therapy did not suggest that treatment within nine days produced better visual results than that for either controls or those treated later. Conclusions Hyperbaric oxygen therapy using 100% oxygen and 2.0 absolute atmospheres of pressure did not produce a significant improvement in visual acuity or visual field for patients with acute nonarteritic anterior ischemic optic neuropathy.

Purpose To examine the effect of aspirin use on the visual outcome of nonarteritic anterior ischemic optic neuropathy. Methods This retrospective case-controlled study included 23 patients who used aspirin regularly before and during the course of nonarteritic anterior ischemic optic neuropathy and 55 control patients with nonarteritic anterior ischemic optic neuropathy. Snellen visual acuity in logMAR and mean deviation on automated perimetry were compiled from the initial and final follow-up examinations. Results The comparisons of patients who took aspirin with control patients disclosed that neither initial logMAR (P = .36) nor the follow-up logMAR (P = .95) data differed significantly. There was no significant difference between the groups for the initial (P = .60) and the follow-up mean deviation (P = .41). Conclusion Aspirin use does not improve the visual outcome of patients with nonarteritic anterior ischemic optic neuropathy. Additional studies are needed to further elucidate this issue.

Purpose We conducted a pilot clinical trial to determine the efficacy of levodopa in promoting visual recovery in eyes with nonarteritic anterior ischemic optic neuropathy of greater than six months' duration. Methods This prospective, randomized, double-masked, placebo-controlled clinical trial involved 20 subjects with nonarteritic anterior ischemic optic neuropathy of 30 months' mean duration. Subjects were randomly assigned to receive either low-dose levodopa and carbidopa or a placebo for three weeks. At 12 weeks after the baseline visit, the levodopa group then was provided a higher, conventional dose of levodopa and carbidopa for three more weeks. Change in visual function was monitored at four, 12, 16, and 24 weeks after the baseline visit. Results At 12 weeks after the baseline visit, the levodopa group experienced a significant (P = .016) mean difference in improvement of visual acuity of 5.9 letters from the placebo group. At 24 weeks after the baseline visit, a significant treatment effect (P = .036) for visual acuity was still evident; the levodopa group had a mean gain in improvement of 7.5 letters difference from baseline from the placebo group. Three subjects in the levodopa group experienced a doubling of the visual angle as denoted by a gain of at least 15 letters. Significant improvement was not observed for color vision (P = .82) or mean deviation of visual field loss (P = .82). Conclusion The study found significant improvement of visual acuity among subjects receiving levodopa and carbidopa despite long-standing visual loss from nonarteritic anterior ischemic neuropathy. Confirmation of our results is awaited from larger population studies and with a longer follow-up time interval regarding the efficacy of levodopa in reversing visual loss in this disease.

PURPOSE: This study analyzes the temporal relationship between intraocular lens surgery and nonarteritic anterior ischemic optic neuropathy (NAION). DESIGN: Retrospective cohort study. METHODS: Eighteen cases of NAION in 17 subjects occurring within 1 year after lens-related surgery were identified with a retrospective review of patients diagnosed with NAION. The temporal relationship between NAION onset and surgery was evaluated by using an exact chi-square test of goodness of fit to compare the observed with a uniform distribution, which would be expected if intraocular surgery were not causal. RESULTS: All 18 cases occurred within 6 months of surgery (mean interval, 35 days; range, 1-130 days), which is significantly different from a uniform distribution (P

No effective treatment has been established for nonarteritic anterior ischemic optic neuropathy. Although most cases occur spontaneously, acute hypotension plays a clear role in a subset of patients. We examined three patients with severe visual loss from ischemic optic neuropathy induced by hypotension. The first patient developed anterior ischemic optic neuropathy after excessively rapid correction of malignant hypertension. In the second patient, anterior ischemic optic neuropathy occurred after an episode of orthostatic hypotension from systemic hypovolemia. The third patient developed anterior ischemic optic neuropathy after becoming hypotensive during a routine hemodialysis session. Measures were undertaken immediately to reverse the hypotension in all three patients. This intervention resulted in partial recovery of vision in each patient.

Proximal constriction (retinal arteries narrower near the disk than further down the stream in the retina) was present in 96 of 226 eyes (42%) with classic glaucoma or normal-tension glaucoma, but it was present in only 11 of 206 eyes (5%) that were normal, had ocular hypertension, or had retinal disease not affecting the optic nerve. In cases of glaucoma with proximal constriction over only part of the disk circumference, its location corresponded to the sector with the greatest cupping in 60 of 66 cases (91%) and likewise corresponded to the sector in which the peripapillary zone of absent retinal pigment epithelium was widest in 48 of 55 cases (87%). Proximal constriction was also present in 16 of 45 eyes (36%) with nonischemic types of nonglaucomatous optic atrophy. The nonarteritic form of anterior ischemic optic neuropathy had proximal constriction in 19 of 28 eyes (68%), which was more frequent than in those with glaucoma (P = .017). Only one of nine eyes with the arteritic form of anterior ischemic optic neuropathy had proximal constriction, which was a lower prevalence than in those with glaucoma (P = .066). General arterial narrowing (throughout the retinal course) was present in 111 of 204 (54%) of those with moderate optic nerve damage and 100 of 128 (78%) of those with severe optic nerve damage in all categories, compared with 29 of 208 (14%) of the controls with no optic nerve damage. Unlike proximal constriction, the generalized narrowing was related to severity of optic nerve damage and not to the disease category.

To test whether comparison of the correlation between optic disc rim area and retinal nerve fiber layer thickness (rim-RNFL correlation) can differentiate eyes with nonarteritic anterior ischemic optic neuropathy (NAION) from eyes with open-angle glaucoma (OAG).Prospective cross-sectional study.One hundred and thirteen eyes with OAG and 22 with NAION were included in this study. The rim-RNFL correlation in OAG eyes was analyzed in global and 12-clock-hour parameters using rim areas determined by Heidelberg retina tomography (HRT II) and RNFL thicknesses determined by optical coherence tomography (Cirrus OCT). The eyes with NAION were determined whether to be out of the 95% prediction interval (PI) for the rim-RNFL correlation of OAG in global and clock-hour parameters.A significant linear rim-RNFL correlation was observed in global and all clock-hour sectors, except the 3-, 4-, and 9-o'clock sectors, in OAG (0.045r(2)0.64, P.05, respectively). All eyes with NAION were outside the 95% PI of the rim-RNFL correlation of OAG in at least 1 clock-hour sector in terms of clock-hour parameters, as compared with 63.6% of eyes in terms of global parameter. All NAION eyes (n = 21) with 7- or 11-o'clock involvement had a rim-RNFL correlation outside the 95% PI of OAG for corresponding clock-hour sectors.By comparison of the rim-RNFL correlation, eyes with NAION were found to be well differentiated from OAG eyes, especially in clock-hour sectors. It might be an objective approach to discriminate NAION from OAG.

The anatomic characteristics of a relatively small optic nerve head, absent to small physiologic cup, abnormal branching pattern of central retinal vessels, and a lush nerve-fiber bundle layer elevating the disk margins are associated with the occurrence of certain ischemic disease states. These diseases include the following: (1) nonarteritic anterior ischemic optic neuropathy, (2) anterior ischemic optic neuropathy of the young, (3) the papillopathy in patients with juvenile insulin-dependent diabetes mellitus, and (4) Leber's hereditary optic neuropathy. The finding of such a disk at risk should signal the possible later development of visual dysfunction. Ordinarily, when an ophthalmologist discusses risk factors in relationship to the optic disk, the topic is that of open-angle glaucoma and the predictability of the ultimate development of visual field loss. In the early 1980s, Hoyt suggested that certain disk characteristics may predispose an individual to the development of nonarteritic anterior ischemic optic neuropathy (Hoyt, W. F., unpublished data, presented at the Rocky Mountain Neuro-Ophthalmologic Society Meeting, February 1982). Specifically, in these cases he noted that the unaffected eye has a small or absent physiologic cup. Several investigators went on to confirm Hoyt's observation that these crowded disks are at risk for developing nonarteritic anterior ischemic optic neuropathy."! The hallmarks of the disk at risk are as follows: (1) relatively small optic nerve head, (2) absent to small physiologic cup, (3) increased number of branches of the central retinal vessels within the disk, and (4) a normal, healthy-appearing nerve-fiber bundle layer with heaping up of at least the superior, nasal, and inferior fibers (Fig. 1). These disks are similar in many ways to those described by Rosenberg, Savino, and GlaserS,6 as being characteristic of pseudopapilledema. Presumably, a small physiologic cup is the

A 68-year-old man had visual loss secondary to isolated choroidal nonperfusion as a clinical manifestation of giant cell arteritis. Ophthalmoscopy disclosed scattered yellow-white lesions at the level of the retinal pigment epithelium in the posterior pole of the right eye. Intravenous fluorescein angiography demonstrated marked delay in choroidal filling of the macula in the right eye. There was no ophthalmoscopic or angiographic evidence of anterior ischemic optic neuropathy or central retinal artery occlusion. After approximately 72 hours of intravenous corticosteroid therapy, the patient's visual acuity improved and repeat intravenous fluorescein angiography showed normal choroidal circulation. Isolated choroidal ischemia is a potential cause of reversible visual loss in patients with giant cell arteritis.

This study was undertaken to understand better how damage to the anterior visual pathway may affect the relationship between the visual and pupillomotor systems. The relative afferent pupillary defect and the interocular difference in visual field mean deviation (determined by the Humphrey Field Analyzer Statpac program) were correlated in 137 patients. A moderate linear correlation (r = .66) was found. In 25 patients tested by both static and kinetic perimetry, the correlation could not be significantly improved by considering field loss outside of 30 degrees. The correlation was further studied in four subcategories of diagnosis: optic neuritis (n = 36), idiopathic intracranial hypertension (n = 26), compressive optic neuropathy (n = 14), and anterior ischemic optic neuropathy (n = 7). In compressive optic neuropathy and idiopathic intracranial hypertension, the difference in mean deviation between the two eyes was associated with a larger relative afferent pupillary defect than in optic neuritis and anterior ischemic optic neuropathy. In optic neuritis, the correlation was the poorest. These results indicate that diseases of the afferent visual system may not necessarily affect visual threshold (as tested by static perimetry) and the pupillary light reflex (a suprathreshold test) in the same way.

Clinical data and fundus fluorescein angiograms were analyzed from 35 patients with acute (onset less than four weeks) anterior ischemic optic neuropathy. Nineteen of the 35 patients (54%) had nonarteritic disease, and 16 patients (46%) had giant cell arteritis confirmed by biopsy. Patients with arteritis had higher erythrocyte sedimentation rates, larger cup/disk ratios, and delayed fluorescein dye appearance and choroidal filling times. Three additional patients with cranial arteritis confirmed by biopsy, but without visual loss, had angiographic characteristics similar to patients with arteritic ischemic neuropathy. We consider fluorescein angiography a valuable diagnostic adjunct in identifying patients with giant cell arteritis.