Today in the office I saw the patient with the subconjunctival hemorrhage, or broken blood vessel in the eye, in this photo. It is always fun to see subconjunctival hemorrhage in the office because it is so easy to diagnose and the news is universally good. Nothing else really looks like a subconjunctival hemorrhage, but it certainly gets your attention if you have one. If you think of it as just a broken blood vessel in the eye you can imagine how it will look.
The part of the eye that can be seen from the outside consists of the iris and the pupil which are covered by the cornea, and the white part of the eye, the sclera, which is covered by a very thin layer of clear tissue called the bulbar conjunctiva. The conjunctiva covers the white part of the eyeball and wraps under the eyelids where it is called the palpebral conjunctiva. The tiny blood vessels that course through the conjunctiva are usually barely visible. When the conjunctiva is inflamed from allergy, viral or bacterial infection, or other causes of irritation these vessels become engorged and the eye appears pinkish. This is sometimes called pink eye.
When one of these tiny blood vessels in the bulbar conjunctiva breaks a tiny drop of blood leaks into the space between the conjunctiva and the tough leathery white of the eye. This blood spreads into a very thin but bright red layer making it look like the whole eye is covered with blood. It looks just like what it is, a broken blood vessel in the eye. The blood can spread to the whole white area of the eye, or just involve either the inner aspect or the outer aspect of the eye. This condition is called a subconjunctival hemorrhage. The “sub” prefix means beneath or under the conjunctiva.
There are several common causes of subconjunctival hemorrhage, but often a person has no idea how the blood vessel was broken. The most classic of the causes of subconjunctival hemorrhage is labor in pregnant women. The violent pushing required to expel the fetus commonly causes a broken blood vessel in the eye. Other fairly common reasons people get a broken blood vessel in the eye are minor trauma, i.e. being poked in the eye, blunt trauma, i.e. being punched in the eye, and sneezing, coughing or rubbing an eye that itches from allergies.
A subconjunctival hemorrhage gradually clears up over a few days to a few weeks time. The initial bright redness disperses and the blood is reabsorbed. Usually within 3-5 weeks the redness is completely gone and recovery is complete. In situations where a person is on an anticoagulant like warfarin or Pradaxa, or an anti-platelet agent like aspirin or Brilinta the bleeding from the broken blood vessel in the eye may be more extensive than usual, but even in these cases the blood usually is reabsorbed fairly quickly.
It is important to differentiate subconjunctival hemorrhage from hyphema. Hyphema is bleeding into the anterior chamber of the eye behind the cornea, and appears like blood is filling up the space behind the cornea. Hyphema is an ophthalmologic emergency and needs opthamologic consultation. Subconjunctival hemorrhage does not affect vision, whereas hyphema usually blocks the visual field. It is not usually difficult to tell the difference but if there is any question you should definitely see your physician to have your eye examined.
The bright redness of a subconjunctival hemorrhage is not at all like the pinkness of conjunctivitis. Conjunctivitis on close examination looks like the blood vessels in the conjunctiva are more noticible or injected looking. With subconjunctival hemorrhage it looks like a pool of blood is covering the eyeball, and looks just like what you would expect from a broken blood vessel in the eye once you understand the anatomy of the conjunctiva and the eye.
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