What is Boxcarring?

Over the course of about a month, the inner retina becomes atrophic as the swelling resolves. Examination of the retinal blood vessels shows segmental blood flow, classically described as boxcarring.

What does CRAO mean?

When 1 of the vessels that carry blood to your eye’s retina gets blocked, you can lose your eyesight. This problem often happens suddenly and without any pain. This is called a central retinal artery occlusion (CRAO).

How long can the retina survive without oxygen?

The retina may not survive after ischemia lasting longer than 90 minutes.

How is CRAO diagnosed?

A CRAO diagnosis is based on recognizing its clinical features from the patient history and ocular examination. CRAO presents as sudden nonpainful visual loss in one eye, with a Snellen VA of counting fingers or worse in 74% of patients. Ocular findings are based upon fundoscopy, fluorescein angiography, and OCT.

Can CRAO be cured?

Therefore, while CRAO is a disease that does not have a treatment, nevertheless it needs to follow the same principles of treatment as any other vascular end organ ischaemic disease. That is, to attempt to reperfuse ischemic tissue as quickly as possible and to institute secondary prevention early.

Is CRAO reversible?

Treatment and prognosis Unfortunately, there is no clinically proven treatment for CRAO. Several therapies may be used including: Hyperventilation—inhaling carbogen, a mixture of 95% oxygen and 5% carbon dioxide, to attempt to dilate the retinal arteries and cause the clot to dislodge.

What is boxcarring of the retinal vessels?

Examination of the retinal blood vessels shows segmental blood flow, classically described as boxcarring. This is best appreciated with slit-lamp biomicroscopy. Over about the course of a week, the vessels reperfuse. Central retinal artery occlusion with cilioretinal artery sparing

What happens when the central retinal artery is damaged?

The central retinal artery supplies the inner retina. Occlusion of the retinal arteries results in ischemia of the inner retina. When the inner retina is damaged, it first becomes very edematous. Over time, the edema resolves and the inner retina atrophies.

What is an occlusion of the retinal vessels?

It is an obstruction of retinal blood flow that may be due to an embolus causing occlusion or thrombus formation, vasculitis causing retinal vasculature inflammation, traumatic vessel wall damage, or spasm.

What is the prognosis of central retinal artery occlusion?

Over time, the edema resolves and the inner retina atrophies. In central retinal artery occlusion , the outer retina is perfused by the choroidal circulation and some inner retina tissue may survive, thus some vision is preserved. Over the course of about week, the occlusion may recannulate.