Hypoperfusion syndrome occurs when the eye lacks blood perfusion secondary to carotid artery blockage or ophthalmic artery blockage. Severe blockage (90%) can lead to progression from hypoperfusion into ocular ischemic syndrome.
Terminology debate: venous stasis retinopathy vs. hypoperfusion syndrome.
Presentation
- Patient may complain of dull, chronic ache in the affected eye, and photostress recovery time is almost always significantly increased. Reverse is also true.
- TIA symptoms (amaurosis fugax, etc.) may or may not be present.
Diagnosis
- Blockage in the carotid artery can be detected by the presence of a bruit and decreased pulse strength.
- A bruit is audible when the lumen of the artery is approximately between 30% and 85% occluded. A swishing sound is present as the blood is forced past the obstruction.
- Best detected with the bell of the stethoscope but the diaphragm may be used.
- Definitive diagnosis requires a combination of Doppler carotid ultrasounds and/or an angiogram of the artery. Doppler is less invasive but also less sensitive.
- Blockage of the ophthalmic artery is very difficult to detect and is essentially a diagnosis of exclusion.
- The typical ocular findings consist of dot and blot hemorrhages (due to pooled blood in damaged capillaries) in the mid to far periphery which spare the posterior pole. The veins become dilated but not tortuous. (In ocular ischemic syndrome, the same findings are accompanied by neovascularization of the disc, retina, and iris. Congestion of vessels, corneal edema, iritis, and a sluggish pupil are often present. Neovascular glaucoma is less common than would be expected.)
- Often unilateral but can be bilateral (20%) if there is significant blockage present on both sides
- If presented with these ocular findings, one must check the carotid arteries, question the patient regarding TIA symptoms, and order carotid testing, ESR, C-reactive protein.
Treatment
- Treatment consists of medical management of the blocked artery via diet, pharmaceuticals, or endarterectomy surgery. Surgery is not performed when there is 100 % blockage due to the very high risk of an embolic event and a stroke on the operating table.
- PRP and cryotherapy are often attempted in OIS but are generally less successful than in other conditions resulting in neovascularization.
Five-year mortality rate of 40%
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