Blepharospasm is any abnormal contraction or twitch of the eyelid, which can be seen in rabbits with various eye conditions. It is usually a sign of an underlying cause and may indicate the rabbit is experiencing discomfort, so it is important that your rabbit has appropriate veterinary treatment.
What does Blepharospasm mean?
The term blepharospasm means excessive blinking of one or both eyelids. This can appear as a full blink or as a twitch. This can be present all the time or can be intermittent.
What is normal?
Rabbits have large, prominent eyes that are positioned on the side of the head. This is typical for a prey animal as it gives them a near 360° field of vision (except for a blind spot behind the head and right in front of their nose). They blink around 10-12 times per hour. Blinking, together with secretions from the glands in the third eyelid and lacrimal glands, help to clean and moisten the eyeballs so they don’t dry out. This is perfectly normal and should not cause you any concern.
What signs will my rabbit show if it has blepharospasm?
Abnormal signs include:
- Excessive and uncontrollable blinking – this may last for a few minutes or several hours.
- Squinting - increased sensitivity to light.
- The eyelid may be red or swollen, especially if they are rubbing or scratching at the eye due to irritation.
- The eyeball may look dry.
- Depression, reluctance to move, or eat – often due to pain or discomfort.
What causes the condition?
There is no definite cause of the condition and it likely that it is a symptom of another condition, rather than a primary cause of illness.
Often irritation from dust or other particles that have got into the eye are likely to be the cause. The rabbit will blink excessively in an attempt to clear the irritation. There are other possible causes which may include:
- Corneal ulcer – an ulcer on the eyeball.
- Sensitivity to light – rabbits who are in direct and bright sunlight.
- Conjunctivitis – if there is an infection within the eye or eyelids causing irritation.
What will my vet do to diagnose and treat my rabbit?
Your vet will perform a thorough clinical examination. They will want to rule out a corneal ulcer. This is performed by placing a special dye onto the eyeball. This will change colour if an ulcer is detected. They will also look at the eye with an ophthalmoscope (an instrument for inspecting the the eye) to access the different areas of the eyeball.
They may also attempt to flush the eyeball (which can normally be performed conscious) to ensure there is nothing irritating the eye.
What treatment will be needed?
Treatment will depend upon the cause. If there is an obvious irritant, then this can be removed. It may be that the rabbit accommodation needs looking into to ensure it isn’t dusty, which may be causing or exacerbating the problem.
Medical conditions, such as a corneal ulcer or conjunctivitis will require veterinary treatment including medications and pain relief. Some corneal ulcers need a surgical procedure that may need to be performed under sedation or general anaesthesia.