Risk of Stroke After Nonarteritic Anterior Ischemic Optic Neuropathy.

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.

Bilateral optic neuropathy related to severe anemia in a patient with alcoholic cirrhosis: a case report and review of the literature.

Anemia appears frequently in patients with alcoholic liver disease (ALD) but has never been linked to bilateral nonarteritic anterior ischemic optic neuropathy (NAION). A 65-year-old woman with a medical history of alcoholic cirrhosis was admitted for bilateral NAION. On admission, she was found to have a low arterial pressure and severe normocytic anemia (48 g/L). The anemia was related to chronic bleeding due to antral gastritis along with other factors associated with ALD. The applied treatment consisted of urgent transfusion followed by high doses of proton-pump inhibitors, iron and vitamin supplementation, and support in lifestyle measures. Her hemoglobin levels remained stable after 2 years but the patient still suffered from visual loss. This case highlights the link between anemia and bilateral NAION in ALD patients. The optic nerve head is prone to infarction in this context due to the vascularization characteristics of ALD. Hemoglobin levels should be monitored in ALD patients to avoid the severe complication of NAION.

Seeing the sound after visual loss: functional MRI in acquired auditory-visual synesthesia.

Acquired auditory-visual synesthesia (AVS) is a rare neurological sign, in which specific auditory stimulation triggers visual experience. In this study, we used event-related fMRI to explore the brain regions correlated with acquired monocular sound-induced phosphenes, which occurred 2 months after unilateral visual loss due to an ischemic optic neuropathy. During the fMRI session, 1-s pure tones at various pitches were presented to the patient, who was asked to report occurrence of sound-induced phosphenes by pressing one of the two buttons (yes/no). The brain activation during phosphene-experienced trials was contrasted with non-phosphene trials and compared to results obtained in one healthy control subject who underwent the same fMRI protocol. Our results suggest, for the first time, that acquired AVS occurring after visual impairment is associated with bilateral activation of primary and secondary visual cortex, possibly due to cross-wiring between auditory and visual sensory modalities.

Progesterone treatment in two rat models of ocular ischemia.

PURPOSE: To determine whether the neurosteroid progesterone, shown to have protective effects in animal models of traumatic brain injury, stroke, and spinal cord injury, is also protective in ocular ischemia animal models. METHODS: Progesterone treatment was tested in two ocular ischemia models in rats: a rodent anterior ischemic optic neuropathy (rAION) model, which induces permanent monocular optic nerve stroke, and the middle cerebral artery occlusion (MCAO) model, which causes transient ischemia in both the retina and brain due to an intraluminal filament that blocks the ophthalmic and middle cerebral arteries. Visual function and retinal histology were assessed to determine whether progesterone attenuated retinal injury in these models. Additionally, behavioral testing and 2% 2,3,5-triphenyltetrazolium chloride (TTC) staining in brains were used to compare progesterone's neuroprotective effects in both retina and brain using the MCAO model. RESULTS: Progesterone treatment showed no effect on visual evoked potential (VEP) reduction and retinal ganglion cell loss in the permanent rAION model. In the transient MCAO model, progesterone treatment reduced (1) electroretinogram (ERG) deficits, (2) MCAO-induced upregulation of glutamine synthetase (GS) and glial fibrillary acidic protein (GFAP), and (3) retinal ganglion cell loss. As expected, progesterone treatment also had significant protective effects in behavioral tests and a reduction in infarct size in the brain. CONCLUSIONS: Progesterone treatment showed protective effects in the retina following MCAO but not rAION injury, which may result from mechanistic differences with injury type and the therapeutic action of progesterone.

Correlation between optic disc atrophy and aetiology: anterior ischaemic optic neuropathy vs optic neuritis.

BACKGROUND: The morphologic features of swollen disc in the acute stage of optic neuritis and anterior ischaemic optic neuropathy (AION) have been extensively investigated in contrast to the morphologic features of optic disc atrophy after these events. OBJECTIVE: : A prospective study to evaluate the morphologic features of optic disc atrophy 6 months or more after optic neuritis and nonarteritic AION. PATIENTS AND METHODS: A total of 35 optic discs after nonarteritic AION (n=27) and 24 after optic neuritis (n=19) in otherwise healthy subjects have been evaluated by direct fundoscopic examination with a +90 diopters lens and optic disc photography. The average age of patients at the onset of AION was 57.8 years (range: 38-80) and at the onset of optic neuritis was 32.6 (range: 19-46). The female:male ratio was 18 : 17 in the former and 15 : 9 in the latter. The evaluated parameters included: degree of rim pallor (0 to +3), location of rim pallor, height of rim above the retina, depth and width of cup, peripapillary retinal artery to vein (A : V) ratio, and peripapillary pigment epithelial atrophy. A comparison was made also with 17 age-matched normal discs of 17 patients. Statistical significance was calculated with chi(2) and Fisher's exact test. RESULTS: Most of the discs after AION were paler (+2: 70%, +3: 26%) than after optic neuritis (normal colour: 8%, +1: 58%, P< or =0.007). Rim segmental involvement after AION was usually either superior 'altitudinal' (53%) or inferior 'altitudinal' (29%), whereas after optic neuritis, it was usually either temporal-central (papillomacular) (42%) or diffuse temporal (42%, P<0.0001). Discs had lower A : V ratio (1 : 3, 40%) after AION compared with optic neuritis (1 : 3, 8%) (P=0.007). There were no significant differences between the two groups in height of the rim, cupping, and peripapillary atrophy. CONCLUSIONS: : A combination of the degree of rim pallor, location of rim pallor, and A : V ratio may be of value in assessing the aetiology of optic disc atrophy when no previous clinical data are available and a compressive lesion has been ruled out.