OCT Angiography in Arteritic and Non Arteritic Anterior Ischemic Neuropathy

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.

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.

Eligibility Criteria:
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.