I did not perceive that I had double vision, but the VEE testing revealed that my brain (and eyes) were having to work excessively hard to hold the two images from my eyes together. This was causing headaches and excessive fatigue.

It was very very easy for the optometrist to break my single image into a double image, and very difficult for me to reassemble it once he did.

I also had difficulty switching between near and far. I could do it, but the effort it required of my brain and eyes again was causing headaches and fatigue. It could also cause nausea, I think.

It is definitely worth having the VEE in my opinion.

You can read more about the vision difficulties experienced after brain injury at http://www.braininjuries.org