Is it unusual to need prism lenses then? I do have a large benign pineal cyst slightly pushing on my tectum. Could this be causing this?
There are some very serious things that can cause double vision (brain tumors, myasthenia gravis, small strokes, etc). I would suggest you see either a eye muscle Eye MD (strabismus specialist/pediatric ophthalmologist) or a neuro-ophthalmologist. Find one at www.aao.org
JCH III MD