Sounds like you know more than me. Where did you gain your information? Have any good references? First symptom happened like lightening one day while biking. Down, sides and forward. The shift was vertical. It was very weird. One eye was looking at the road, as if seeing the road up close and the other looking forward or even a little up. No surgery just ground in prisms. They work. Took a couple of days to adjust. Distand vision first cleared up then close- computer distance and reading. Have had them a week or two. Sorry, I have no more technical infor on the prisms.