Refers to the impairment of horizontal eye movements caused by damage to connections between nerve centers in the brain stem.
In internuclear ophthalmoplegia, the nerve fibers that coordinate both eyes in horizontal movements are damaged.
These fibers connect collections of nerve cells that originate from the 3rd cranial nerve, the 4th cranial nerve and the 6th cranial nerve.
Isolated decreased eye addiction.
Caused by:
In older people: A stroke with only one eye is affected.
In younger people: Multiple sclerosis and both eyes are often affected.
Less common causes include Lyme disease, tumors, and head injuries, thyroid related eye disease,, inflammatory pseudotumor.
Horizontal eye movements are impaired, but vertical eye movements are not.
The affected eye cannot turn inward, but it can turn outward.
When a person looks to the side opposite the affected eye, one cannot move past the midline and the affected eye looks straight ahead.
As the other eye turns outward, it often makes repetitive fluttering movements called nystagmus
That is, the eye rapidly moves in one direction, then slowly drifts in the other direction.
People with internuclear ophthalmoplegia may have double vision.