OCT Angiography in Arteritic and Non Arteritic Anterior Ischemic Neuropathy

Study Overview
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Brief Summary
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Anterior ischaemic optic neuropathy results from infarction of retrolaminar portion of the optic nerve head, caused by occlusion of the posterior ciliary artery. Non arteritic anterior ischaemic optic neuropathy affects more frequently people between 50 and 70 years of age, with vasculopathic risk factors. Arteritic anterior ischaemic optic neuropathy is caused by the Horton disease, affects an older population and is an ophthalmologic emergency because of the bilateralisation's risk. The aim of this study is to compare the peripapillar vascular density of anterior ischaemic optic neuropathy eyes (arteritic and non arteritic) with normal eyes after the disappearance of the papillar edema, with oCT-angiography. The investigators will include patients with anterior ischaemic optic neuropathy and normal patients. For each participant, the investigators will estimate the best visual acuity, intra-ocular pressure, make a fondus, measurement of retinal nervous layer thickness, ganglionar cells layer thickness, and a macular and papillar OCT angiography during a consultation (duration 30 min). The investigators will be able to know if there is a modification of the peripapillary vascularisation subsequent to the occlusion of the posterior ciliary artery there is a difference between arteritic and non arteritic anterior ischaemic optic neuropathy, there is a repercussion of the neuropathy on the retinal layers, there is a difference in peripapillar vascularisation by age.

Detailed Description
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Anterior ischaemic optic neuropathy results from infarction of retrolaminar portion of the optic nerve head, caused by occlusion of the posterior ciliary artery. Non arteritic anterior ischaemic optic neuropathy affects more frequently people between 50 and 70 years of age, with vasculopathic risk factors. Arteritic anterior ischaemic optic neuropathy is caused by the Horton disease, affects an older population and is an ophthalmologic emergency because of the bilateralisation's risk. The aim of this study is to compare the peripapillar vascular density of anterior ischaemic optic neuropathy eyes (arteritic and non arteritic) with normal eyes after the disappearance of the papillar edema, with oCT-angiography. The investigators will include patients with anterior ischaemic optic neuropathy and normal patients. For each participant, the investigators will estimate the best visual acuity, intra-ocular pressure, make a fondus, measurement of retinal nervous layer thickness, ganglionar cells layer thickness, and a macular and papillar OCT angiography during a consultation (duration 30 min). The investigators will be able to know if there is a modification of the peripapillary vascularisation subsequent to the occlusion of the posterior ciliary artery there is a difference between arteritic and non arteritic anterior ischaemic optic neuropathy, there is a repercussion of the neuropathy on the retinal layers, there is a difference in peripapillar vascularisation by age.

Official Title
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Study of Peripapillary Vasculature With OCT-angiography in Arteritic and Non Arteritic Anterior Ischemic Neuropathy After Oedema Disappearance

Conditions
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Neuropathy, Optic

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with arteritic or non-arteritic anterior ischemic optic neuropathy ,> 3 months or after disappearance of papillary edema Control subjects, with normal optic nerve and symmetrical appearance , without diagnosed glaucoma (intraocular tension lower than 21mmHg) and without antecedent of retinal or intraorbital pathology. Patient with cataract can be included, within the limits of the good acquisition of images. Free, without tutorship or curatorship or subordination Benefiting from a Social Security scheme or benefiting through a third party Giving their non-opposition, after clear and fair information on the study Exclusion Criteria: with ocular or retinal pathology leading to irreversible visual impairment or macular involvement (strong myopia> 6 diopters, astigmatism> 3 diopters, retinitis pigmentosa, occlusion of the central artery of the retina or central vein of the retina , CRSC, diabetic retinopathy), or history of ocular or retinal surgery except cataract surgery. having an alteration of the optic nerve related to another pathology (NORB, glaucoma evolved with cup / disc> 0.7 or poorly balanced tension, optic neuritis), performing the exam impossible or poor image quality impossibility of giving one's non-opposition, not benefiting from a social security scheme or benefiting from it through a third person benefiting from enhanced protection, namely: minors, persons deprived of their liberty by a judicial or administrative decision, persons staying in a health or social institution, adults under legal protection.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with anterior ischaemic optic neuropathy<br>estimation of best visual acuity, fondus, measurement of retinal nervous layer thickness, ganglionar cells layer thickness, and a macular and papillar OCT angiography during a consultation | |
| control group. Normal eyes<br>estimation of best visual acuity, fondus, measurement of retinal nervous layer thickness, ganglionar cells layer thickness, and a macular and papillar OCT angiography during a consultation | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| compare peripapillary vascular density in eyes with anterior ischaemic optic neuropathy and in normal eyes with OCT angiography | Measurement of vascular density by percentage of area occupied by peripapillary vessels in patients with anterior ischemic optic neuropathy and control subjects | 10 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| compare vascular microvascular density at the macular level with angio-OCT in patients with anterior ischemic optic neuropathy and control subjects | Measurement of macular microvascular density by percentage of the area occupied by the vessels in patients with anterior ischemic optic neuropathy and control subjects, | 10 minutes | 
| Compare Peripapillary and Macular Mirovascular Differences in Arteritic and Non-Arteritic anterior ischemic optic neuropathy Patients | Measurement of microvascularisation density and its abnormalities (dilatation, defect) on peripapillary angio-OCT images in group with an arteritic optic neuropathy compared to patients with non-arteritic optic neuropathy | 10 minutes | 
| compare the microvascular density of the 2 optic discs in the same patient : with optic neuropathy and the healthy disc | Measurement of peripapillary microvascular density in the eye with anterior ischemic optic neuropathy and healthy contralateral eye in the same patient | 10 minutes | 
| compare the thickness of the peripapillary retinal nerve fibers and the thickness of the ganglionar complex layer in patients with anterior ischemic optic neuropathy and control group | Measurement of retinal nerve fiber thickness (RNFL), and thickness of ganglionic complex layer (GCC) with OCT in 2 groups | 5 minutes | 
| Compare peripapillary and macular microvascular density by age and by sex | Measurement of macular and peripapillary microvascular density on angio-OCT images for comparison between different age groups | 10 minutes |