You can find LOTS of information on glaucoma in cats by searching google. That being said, being blind is CERTAINLY NOT A DEATH SENTENCE! Blind cats do WONDERFULLY well, and adapt very quickly! I wouldn't let the possibility that she could lose her other eye weigh too heavily on the decision to adopt her.
Here is a link to google with the appropriate search terms to find the info you seek: http://www.google.com/search?source=ig&hl=en&q=glaucoma+cat+feline Phaewryn http://ucat.us/domesticcatlinks.html Special Needs Cat Resources

