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/ Source: TODAY
By A. Pawlowski

Democratic presidential candidate Joe Biden was talking about climate change Wednesday night, but it was his eye that caught many viewers’ attention.

The former vice president was taking part in a televised town hall when the outward corner of his left eye seemed to fill with blood.

It appeared to be a subconjunctival hemorrhage, which the U.S. National Library of Medicine simply defines as “a bright red patch appearing in the white of the eye.”

It’s not painful and doesn’t cause changes in vision or swelling, so many people may not even know they have it until they look in the mirror.

A subconjunctival hemorrhage, close up.Alamy Stock Photo

Why does it happen?

The white of the eye is covered by the conjunctiva, clear tissue that contains many tiny blood vessels, the American Academy of Ophthalmology noted.

The capillaries can break and bleed when a person:

  • sneezes, coughs, strains while using the toilet or otherwise experiences a spike in blood pressure.
  • rubs his eyes too hard
  • wears contact lenses
  • has high blood pressure or is taking blood thinners
  • has a viral infection
  • has undergone eye surgery or suffered an eye injury
  • has diabetes

Confined to the conjunctiva, the blood stays in place and can’t be wiped away. The bright red spot looks frightening, but it’s usually harmless, the American Academy of Ophthalmology said.

Such hemorrhages are common in newborns, likely caused by the pressure changes in the baby’s body during childbirth, the U.S. National Library of Medicine noted.

How is it treated?

A subconjunctival hemorrhage usually heals on its own and goes away without any treatment in a matter of days or weeks, depending on its size. Its color may change as it heals.

When is it a concern?

In rare cases, it may be a sign of a serious vascular disorder in older people. Patients who frequently experience such broken capillaries in the eye may get tests to try to find an underlying cause, such as a blood clotting disorder, the Cleveland Clinic noted.

If the redness comes with pain, it could be a sign of a hyphema, a more serious condition where blood collects inside the front of the eye.