Ocular Ischemic Syndrome Clinical Presentation

Updated: Feb 03, 2023
  • Author: Tahira M Scholle, MD; Chief Editor: Andrew G Lee, MD  more...
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Decreased Vision

Decreased vision is the most common symptom associated with ocular ischemic syndrome, occurring in 91% of patients. In one study, most patients (67%) noted gradual vision loss over weeks to months, whereas 12% had decreased vision over days, and another 12% noted decreased vision over seconds to minutes. A history of transient vision loss is present in 10% to 15% of patients with ocular ischemic syndrome (OIS). [2]

Patients with ocular ischemic syndrome can present with variable degrees of visual loss. Up to two thirds of patients can present with visual acuities of 20/60 or worse. One third of patients will have visual acuities of counting fingers or worse. [2, 18]

Visual fields are variable and may show no defect, central scotoma, nasal defect, cecocentral defects, or presence of only a central or temporal island. [7]


About 40% of patients with ocular ischemic syndrome have eye pain. Pain secondary to ischemia is characteristically described as a dull ache over the brow, which begins gradually over a period of hours to days. Lying supine may decrease pain since blood flow is increased. Pain also can result from elevated intraocular pressure in the presence of neovascular glaucoma.



Ophthalmic Examination

Anterior segment

Corneal abnormalities: Descemet folds and corneal edema may be present secondary to ocular hypotony, increased intraocular pressure, or endothelial dysfunction due to ischemia. [2, 4]

Iris neovascularization: Iris neovascularization is encountered in 67% to 87% of affected eyes and can be caused by retinal ischemia, choroidal ischemia, or both.

Neovascular glaucoma: This is elevated intraocular pressure in the presence of angle neovascularization. Neovascular glaucoma is seen in about one third of patients with ocular ischemic syndrome. Lower arterial perfusion to the ciliary body may induce hypotony or normal intraocular pressure despite significant anterior chamber angle neovascularization due to decreased production of aqueous fluid.

Anterior chamber inflammation: Uveitis, characterized by the presence of cells and flare in the anterior chamber, was estimated to occur in up to 20% of eyes. In most cases, the inflammatory reaction is only mild and flare is more prominent than cells.

Cataract: Advanced degrees of lens opacities may be seen in patients with ocular ischemic syndrome. Asymmetric cataract may help support the diagnosis of ocular ischemic syndrome.

Posterior segment

Retinal vessels: Retinal arteries are typically narrow in eyes with ocular ischemic syndrome. The veins are usually irregularly dilated but not tortuous, which can help differentiate ocular ischemic syndrome from central retinal vein occlusion (CRVO). [2, 4, 19]

Retinal hemorrhages: Midperipheral dot-and-blot retinal hemorrhages are observed in 24% to 80% of eyes with ocular ischemic syndrome. Microaneurysms can also be seen.

Cotton-wool spots: These are seen in approximately 5% of eyes with ocular ischemic syndrome and are typically located in the posterior pole.

Neovascularization: Neovascularization of the optic nerve is seen in 13% to 35% of eyes with ocular ischemic syndrome. Retinal neovascularization is less common, and occurs in 3% to 8% of cases. Neovascularization of the optic nerve can be mild, or it can progress into extensive fibrous proliferation, causing secondary vitreous hemorrhage and tractional retinal detachment.

Cherry-red spot: The cherry-red spot appears as a result of ischemia involving the inner layers of the retina, as typically seen in cases of central retinal artery occlusion. It is noted in 12% of eyes with ocular ischemic syndrome.

Optic disc: Optic disc pallor, cupping, or edema are also noted in patients with ocular ischemic syndrome.



The most common cause of ocular ischemic syndrome is atherosclerosis of the carotid artery. In most cases, stenosis must be 90% or greater to cause ocular ischemic syndrome.

Other causes include the following:

  • Giant cell arteritis
  • Takayasu arteritis
  • Aortic arch syndrome


Potential complications include the following:

  • Decreased vision (total blindness is uncommon)
  • Neovascular glaucoma
  • Increased risk for heart attack, stroke, or death (The 5-year mortality rate in patients with ocular ischemic syndrome is about 40%, with the leading cause of death being myocardial infarction. [14] )