This is a very bad problem. To put things into perspective before modern RD surgery these eyes went blind 100%. With modern technique 90% of retinas can be re-attached with one surgery. Even then the eye often not regain full vision especially of macula off RD. 10% require 2 or more surgery. Perhaps 1% cannot be reattached.It is not possible to say what type of vision you husband will have a year from now. The chance of a full recovery is very low. The most important thing is his OTHER eye. It has a chance of RD that may be as high as 10% Ask the retina surgeon about problems and risk of OTHER EYE. Be sure to take extra care of good eye, avoid injury, yearly eye exam, live healthy lifestyle, don't smoke, keep weight, blood pressure, blood sugars, triglycerides all good.