Double vision (Diplopia)
The most common cause of acute binocular double vision is Micro vascular cranial nerve palsy. Most common precipitating factor is uncontrolled diabetes and/or Hypertension.
What is the cause of cranial nerve palsy in diabetes?
It is due to decrease in the blood supply to the nerves supplying the eye muscles causing it not to work thereby causing misalignment along the two eyes.
How can I get relieved of this troublesome double vision?
The diplopia (double vision) will take some time to resolve (about 6 – 8 weeks). However, it will always resolve completely within that time provided the diabetes and hypertension are under control. During the acute phase, occluding on eye with an occluder fixed on the glasses or a patch can temporarily relieve the troublesome diplopia.
Can I have some other serious underlying problem? Isn’t a CT scan or MRI scan necessary?
Most cases of isolated single nerve palsies are not due to any major abnormalities. Costly procedures like CT scan are not immediately required unless there is any other associated problem. However, if the nerve palsy does not get better beyond 3 months in spite of having diabetes and/or hypertension under control, then your doctor will consider a CT or MRI scan.
Why do I have a pain surrounding the eyes?
This pain is due to the decreased blood supply and the associated Ischaemia (reduced blood supply). The pain is temporary and it usually gets relieved with anti-inflammatory medications.
Can cranial nerve palsy cause decrease in my vision?
No, it cannot cause directly a decrease in the vision in the affected eye except for the troublesome diplopia. However, one should remember that there might be an associated retinal pathology (the nerves within the eye responsible for vision) due to the diabetes. These also should be looked for to rule out any diabetic retinopathy by the ophthalmologist.
Will I have a recurrence of this problem?
Some patients may have a recurrence of this problem at some time if their diabetic status is uncontrolled.
What if the double vision doesn’t resolve at all?
In some cases, it may not resolve completely. In such cases if the diplopia is troublesome it can be relieved in the special lenses called prisms fitted onto your glasses or eye muscle surgery can be performed.