The optic nerve links the eyes to the brain. It transmits the visual messages seen to the brain. Once an individual has an optic nerve stroke, the blood vessels supplying oxygen and nutrients to the nerve ends up blocked or constricted which leads to abrupt vision loss.
After a stroke, the individual might have permanent vision loss in one eye. This type of stroke is not the same as a stroke in the brain and does not trigger weakness or inability to move the legs or arms.
What is the cause?
The usual cause of an optic nerve stroke is narrowing or blockage of the arteries or a drop in the blood pressure in the blood vessels supplying the optic nerve.
One is at higher risk if the following are present:
- Small optic nerve
- High cholesterol level
- Certain forms of infections such as syphilis or herpes zoster
- High blood pressure
- Rheumatoid arthritis, lupus or other conditions that affect the immune system
In addition, drugs used to treat erectile dysfunction might increase the risk for an optic nerve stroke.
What are the signs?
The usual indication of an optic nerve stroke is abrupt vision loss in one eye or blurred or vision loss that comes and goes. In case the optic nerve stroke is brought about by low blood pressure, there is loss of vision upon waking up in the morning. This might be due to a drop in the blood pressure while sleeping.
The signs of an optic nerve stroke due to giant cell arteritis include:
- Headache or pain in the scalp or temples
- Scalp pain
- Discomfort while chewing
- Rigidity and pain in the muscles of the shoulders, neck, hips and lower back
- Unexplained weight loss
Management of optic nerve stroke
The treatment for an optic nerve stroke is based on the root cause. If giant cell arteritis is the cause, it must be managed with steroid medications. The vision of the individual might improve after several weeks or months after the stroke.
The individual might continue to experience issues, and, in some cases, the vision might worsen.