Thank you for the question.I am Dr.A.S.Desai and I look forward to assisting you .
First point to be noted is astigmatism would not be treated with prisms. It needs to be corrected with cylinderical lenses
Second point is monocular diplopia
is usually not due to a neurological cause.
Third point is that MS usually involves the eye in the form of optic neuritis
. This cause acute blurring of vision and not diplopia.
Common causes of monocular diplopia are high astigmatism, cataract in early stage, foreign body in the eye. The double vision persists in the affected eye on closing the other eye.
If the double vision disappears on closing one eye or either eye then it is called binocular diplopia. This can have neurological cause. It is better that you consult a neurologist or neuro ophthalmologist to confirm the above.
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