Paralysis of cranial nerves which control eye movement is cranial nerve palsy. It results in the inability to move the eyes. Depending on the nerve which is affected, the movement of the eye is affected. The eye movement is controlled by third, fourth and sixth cranial nerves.
The eyes are moved right and left, up and down, and diagonally with the help of these muscles. This article gives information about the sixth cranial nerve palsy.
Sixth Cranial Nerve Palsy
The following are the disorders which may cause this palsy:
- Tumors
- Head injuries
- Aneurysms
- Multiple sclerosis
- Complications of an eye or ear infection
- Brain infections like a brain abscess, a parasitic infection or meningitis
- Wernicke’s encephalopathy (due to chronic alcoholism)
- Artery blockage supplying the nerves, as it can result from a stroke, diabetes, vasculitis or a transient ischemic attack.
- Respiratory infections (mostly in children)
- Benign intracranial hypertension
Some of the above disorders increase nerve pressure by causing swelling nearby or by increasing skull pressure. Others interfere with the flow of blood to the nerve.
Symptoms
When people look straightly, the eye which is affected cannot turn outward fully and it may turn inward. The affected eye shows double vision when looked side of it. Other symptoms include fluid accumulation in the conjunctiva, headache, numbness in the mouth and face, inability of the eye to move in other directions and loss of vision.
Diagnosis and Treatment
- Doctors can usually identify sixth cranial nerve paralysis easily, but the cause is not more obvious.
- With the use of an ophthalmoscope, the eye check up is done for the evidence of blood vessel abnormalities and tumors increased pressure.
- CT or MRI is done in order to remove tumors or other abnormalities.
- Still, if the unclear results are found, a spinal tap is done to know if the pressure is increased in the skull, or swelling because of an infection or a tumor is compressing the nerves.
