Usually, if there is blood in the eye it’s because a tiny blood vessel on the eye has broken open, causing a portion or all of the white of the eye (sclera) to appear bright red.
This painless blood in the eye is called a subconjunctival hemorrhage; and though they look scary, subconjunctival hemorrhages are common and harmless and can be caused by something as simple as a sneeze or cough.
But, there’s a second type of bleeding in the front of the eye that’s much more serious — it’s called a hyphaema, and it requires immediate attention. (see the difference between the two, below).
What Is A Hyphaema?
A hyphaema is bleeding or a broken blood vessel inside the eye that causes blood to collect in the anterior chamber of the eye — the space between the cornea and the iris that’s normally filled with a clear liquid called the aqueous humor.
The severity of a hyphaema is graded by how much blood accumulates in the eye:
- Grade 0 (microhyphaema): No visible pooling of blood, but red blood cells can be seen within the anterior chamber upon microscopic examination.
- Grade 1: Pooling of blood in less than the lower third of the anterior chamber.
- Grade 2: Blood filling one third to one half of the anterior chamber.
- Grade 3: Blood filling one half to less than the entire anterior chamber.
- Grade 4: Total filling of the anterior chamber with blood. If the blood is bright red, this is called a total hyphaema. If it is dark red-black blood, it’s sometimes called an “8-ball hyphaema.” (see photo below)
In general, the higher the grade of hyphaema, the greater risk of vision loss and long-term damage to the eye. The dark red or black colour of an 8-ball hyphaema (the most dangerous type) is associated with decreased circulation of aqueous humor and decreased oxygen in the anterior chamber of the eye.
What Are Other Symptoms Of Hyphema?
In addition to the blood in the eye, the following symptoms usually are associated with hyphaema:
- Blurry or distorted vision
- Eye pain
- Light sensitivity (photophobia)
Eye pain, sensitivity to light and headache are especially likely to occur if a hyphaema is causing increased intraocular pressure (IOP).
What Causes Bleeding In The Eye?
The most common cause of hyphaema is trauma to the eye. In some cases, a traumatic hyphaema also can occur after eye surgery, including cataract surgery, but this is relatively rare.
It’s also possible for a hyphaema to occur spontaneously, particularly among people who are taking blood thinners (such as warfarin or aspirin) or have a blood clotting disorder (haemophilia). Diabetes also can increase the risk of a spontaneous hyphaema, as can tumour growth in the eye (ocular melanoma).
Is A Hyphema Serious? Are There Complications?
Usually, the blood that collects in the anterior chamber of the eye due to a hyphaema will be reabsorbed by the body without permanent damage to the eye.
In some cases, clotting of this blood will clog or damage the structure in the periphery of the anterior chamber that controls the normal outflow of aqueous humor from the eye. This can cause increased eye pressure that can lead to glaucoma and permanent vision loss.
Also, in some cases, re-bleeding can occur inside the eye after the initial eye injury that causes a traumatic hyphaema. This new bleeding (usually occurring within a few days after the injury) can be more severe and more dangerous than the initial bleeding.
People with sickle cell anaemia or those who simply have the genetic trait for this disease have an increased risk of eye damage from a hyphaema.
In the ED, ensure the patient is given analgesia. The patient should be prioritised and made a P3, and ensure a Doctor or ENP is aware.
Test visual acuities, and check for overlying corneal abrasions with Fluorescein. Check visual fields and eye movements.
All hyphaemas need to be discussed with the on-call Ophthalmologist out of hours, or sent to the Eye Hospital between 08:30 and 16:30. If the advice from the out of hours is to send the patient home and return in the morning, then the follow advice should be given to the patient:
- Limited physical activity
- Head elevation (including when sleeping)
- Wearing an eye shield (if advised to do so)
- Anti-inflammatory medicine (topical or oral)
In the case of a severe hyphaema, surgery may be required and the on-call Ophthalmologist will see the patient straight away.
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