Ischemia of the anterior segment is uncommon because of its rich, collateral circulation.


Main blood supply to the anterior segment:

(1) anterior ciliary arteries (which travel with the extraocular muscles)

(2) posterior ciliary arteries


Causes of ischemia of the anterior segment:

(1) generalized cranial ischemia, often secondary to extensive atherosclerosis

(2) chronic anterior uveitis (including SLE)

(3) sickle cell anemia

(4) hyperviscocity syndrome

(5) surgery for Cranial Nerve III or VI palsy

(6) surgery for a carotid-cavernous sinus fistula

(7) strabismus surgery involving multiple extraocular muscles

(8) surgery for retinal detachment


Clinical findings:

(1) ocular pain

(2) corneal edema

(3) folds in Descemet's membrane

(4) uveitis and inflammation of the anterior chamber

Clinical Findings


reduced perfusion of the iris


Grade 1 plus pupil signs


Grade 2 plus uveitis


Grade 3 plus keratopathy (with corneal edema)




• The "pupil signs" were not defined. My guess is that should be an efferent pupillary defect resulting in anisocoria, which increases in bright light



(1) complicated cataract

(2) iris neovascularization

(3) possibly glaucoma


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