What Is Microvascular Cranial Nerve Palsy?
Microvascular Cranial Nerve Palsy (MCNP) is when the blood flow of cranial nerves in your head is blocked. As a result, you may not be able to move your eye a certain way. Also, you will have double vision. Double vision is when two of a single image-either side by side, or one above the other is seen.
Your brain sends signals to the muscles in your eyes through 3 nerves. If blood flow to one of these nerves is minimized, certain muscles cannot move the eye.
Doctors do not know for sure why the tiny blood vessels that go to your cranial nerves get blocked. MCNP is very common in older adults. It is more likely to happen to those who have diabetes and high blood pressure. In fact, it is sometimes called “diabetic palsy.”
MCNP most the time always gets better on its own in about 6-12 weeks, and your vision returns to normal.
What Are MCNP Symptoms?
The most common MCNP symptoms are problems moving your eyes, blurry vision and double vision. You may find that it takes longer than normal to move your eyes. Or you may not be capable to move your eyes at all in one or more directions.
In certain cases, you may have vertical double vision. This is where two of the same image, one above the other is seen. Tilting your head towards either shoulder may reduce or get rid of this double vision. You could also have both up and down (vertical) and side by side double vision.
You may have a droopy eyelid. You could also have some pain in, or around, your eye. This may occur just before you notice double vision. Unusually, your pupil (the black dot in the center of your eye) gets larger
How Is MCNP Diagnosed?
Your ophthalmologist will do a full medical eye exam. He or she will want to figure out the type of double vision you are having. That can help show which nerves are affected.
Sometimes, you will have tests done to provide detailed images of your eye, such as a CT scan, MRI, or angiogram.
Your ophthalmologist may also refer you to a neurologist.
It is also important to make sure that your blood pressure and blood sugar levels are well controlled.
If your eye muscles do not recover completely on their own, your ophthalmologist may suggest you have eye muscle surgery.
It is very important to tell your opthamologist if your double vision does not go away or if you get new double vision symptoms.
MCNP And Stroke
Risk factors for MCNP could be high blood pressure, diabetes and smoking. These same risk factors increase the likelihood for having a stroke.
How Is MCNP Treated?
MCNP goes away on its own. There is no way to shorten the amount of time it takes to recover from it. Although, there are ways to help cope with your double vision. For example, you can wear a patch on one of your eyes. This most the time helps reduce the symptoms of double vision. You can also try wearing prism glasses. Your ophthalmologist can discuss how they help with double vision, and prescribe them for you.
If you have pain from MCNP, an anti-inflammatory medicine such as ibuprofen may be recommended.
Microvascular Cranial Nerve Palsy (MCNP) is when there is a blockage in blood flow to nerves in your head. As a result, muscles that move your eyes do not work properly. You have trouble moving your eyes a certain way, and you have double vision. Sometimes you have blurry vision or a droopy eyelid. MCNP is more likely to happen to people with high blood pressure and diabetes.
MCNP usually goes away on its own in about 6-12 weeks. Patching one of your eyes or wearing prism glasses can help with double vision while you recover. Sometimes, if the eye muscles do not recover completely on their own, muscle surgery is recommended.
To prevent MCNP, you need to control high blood pressure and blood sugar levels, and quit smoking.