Hyphema in Dogs

Hyphema is the presence of blood within the front (anterior) chamber of the dog’s eye and is a symptom of either serious ophthalmic or systemic disease. The amount of blood within the front chamber can vary. Mild hyphema may appear only as a pinkish-red discoloration to the fluid in the front of the eye, or as red blood settled out on the bottom of the chamber. Severe hyphema is when the entire chamber is filled with blood and the animal is rendered blind.

Hyphema usually originates from bleeding of the iris blood vessels, but the blood may also originate from the ciliary body (tissue behind the iris), choroidal blood vessels (tissue layer beneath the retina), or retinal blood vessels.

Causes of Hyphema in Dogs

Some common causes of hyphema include:

• Direct blunt or penetrating trauma to the head or eye
• Choking or applying excessive pressure around the neck
• Severe uveitis (inflammation of the iris, ciliary body and choroid)
• Certain systemic infections, such as the tick-borne diseases
• Blood clotting disorders
• Systemic hypertension (elevated arterial blood pressure)
• Retinal detachment or tearing
• Chronic glaucoma
• Tumors (cancer) within the eye
• Congenital defects in the eye (rare)

Traumatic and congenital causes are more common in young dogs, while hypertension and most tumors are more common in older dogs. The other causes may occur at any age. In some animals the cause is never determined.

Signs of Hyphema in Dogs

Think your dog might have hyphema? Watch out for the following warning signs:

• Redness within the eye located between the cornea (the clear front covering the eye) and the iris/pupil. The blood may hide a portion of the iris or pupil. It may settle to the bottom of the anterior chamber due to gravity, or it may form an actual blood clot in the chamber.
• Other signs of trauma (bruising, wounds), inflammation or irritation (redness, discharge) to the eye
• Possibly pain with squinting or holding the eye closed
• Decreased vision or blindness in the affected eye(s)

Diagnosis of Hyphema in Dogs

Diagnostic tests may include one or more of the following in your dog:

• Complete medical history and physical examination
• Complete ophthalmic examination. This should include pupillary light reflex testing, Schirmer tear tests, staining of the cornea with fluorescein, tonometry (measurement of pressure within the eye), and examination of the front and back chambers of the eye under magnification
• Complete blood count (CBC), including a platelet count
• Serum biochemistry tests to look for involvement of other organs
• Possibly a urinalysis
• Specialized blood tests to evaluate the blood’s ability to clot
• Blood pressure testing
• Specialized serum tests to detect the presence of certain infections or cancerous processes
• Possible X-rays if there are signs of other organ involvement

Treatment of Hyphema in Dogs

Treatment of the eye is often initiated while a diagnostic work-up is underway and may include:

• Topical corticosteroids, in the form of eye drops or ointments, are used to reduce inflammation within the anterior chamber.
• Topical atropine (1%), in the form of eye drops or ointments, is often indicated to dilate the pupil. Dilation of the pupil helps to relieve pain and to minimize adhesions between the iris and the lens.
• Oral non-steroidal anti-inflammatory medications, such as aspirin or carprofen, are not initially used in most dogs with hyphema because these drugs may interfere with platelet function and increase the risk of further bleeding.
• Treatment for glaucoma is indicated in eyes with elevated intraocular pressure. See the Client Education article on Glaucoma.

Home Care for Dogs with Hyphema

Restrict your dog’s activity and reduce the risk of further bleeding by confining your dog to a small room or crate until the cause of the hyphema is determined and the treatment is well underway.

Because vision is impaired in some cases, do not allow your dog to go outdoors unattended or unsupervised. Do not administer human over-the-counter medications, such as Visine® or other ophthalmic products designed to reduce eye redness or irritation, because these products are ineffective for hyphema.

Do not delay in bringing your dog to your veterinarian, because some causes of hyphema are not only vision threatening, but may also be also life-threatening.