Introduction
Caused by severe stenosis, or atherosclerotic plaques in the ipsilateral carotid artery, usually with an obstruction of 90% or more.
- Can be related to carotid artery dissection, Giant cell arteritis and inflammation like Behcet's disease.
- Significantly less blood getting to ophthalmic artery
Dead Giveaways
Unfortunately no features that can rapidly distinguish between this and other vascular disease.
Most notable to occur:
Arterial attenuation
Dilated non-tortuous veins
Differentiates from CRVO, or impending CRVO due to signs being dilated AND tortuous
MA and retinal haemorrhages in mid-periphery
Venous beading can occur
Telangiectatic capillaries may be found at macula
Note the dilated non-tortuous veins, slight arterial attenuation, but without the white opaque colour from RAO. Good to compare between the eyes.
diagnostic features
Signs that may occur:
Sluggish or fixed semi-dilated pupils due to ischaemia of the pupillary sphincter
RAPD
Iris atrophy
Hypotony due to ischaemia of the ciliary body
Dilated conjunctival and episcleral vessels
Spontaneous hyphema
Asymmetrical cataracts
Corneal oedema with folds
Bullous keratopathy
Ptosis
Ophthalmoplegia
Scleral melting
Most signs occur either due to vessels, or lack of blood supply and thus decreased metabolism
Presenting Symptoms:
The primary complaint is gradual vision loss (90%)
Of that, 67% have vision loss over weeks-months
12% have vision loss in seconds-minutes
37% have very severe vision loss
Severe vision loss is attributed to macular oedema due to capillary telangiectasia
Pain is typically attributed to NV glaucoma
Ache can be alleviated by lying down to help blood travel better