Alphagan P Question

[eric859]

I had wide zone (8mm) lasik about 10 months ago. The hardware used was the VISX® Star S4 Active Trak® Excimer Laser System. I went to the best doctor I could find in New York City. My daytime site is wonderful. I've been tested at the doctors office as having 20/15 vision. At night, however, I have a problem with halos. My dialated pupil size was measured at 7mm prior to the surgery. I went back and the doc took a wavefront picture of my eye (sorry if I'm not using the right terminology) and noticed spherical abberations (light blue) around the outer edges of my cornia which seem to be what's causing my halo issue. My doctor prescribed Alphagan P to shrink my pupil. It works great. I've used it every day for the last 10 days or so about an hour prior to driving. I noticed the other night after not using it that my nightime vision is even worse than before. I've been doing research on this site and others and have seen the term "reboung effect" thrown around a lot. If I understand the term correctly, when you go off Alphagan, your pupil opens even more than it did causing even worse vision at night. Is this rebound effect temporary? How long does it take for your pupil to extend only to it's original maximum size? I'm conserned that I will become dependant on the Alphagan in order to see at night at all and that eventually the pupil constriction effects will wear off leaving me unable to see at night for the rest of my life.

[pavel_g]

Dear Eric,
The rebound effect of alphagan is temporaly. How long this effect takes? - I believe that there is a high variability in this issue, but probably not more than one or few days.

One note - it is possible that you have worse symptoms the day after the use of alphagan not because of rebound effect, but due to dry eyes, which are frequently getting worse day after alphagan use.

If you will use alphagan less frequently (1-2 times a week), you probably will not experience the reduction of effect of alphagan with time.

BTW: your optical zones were planned to be 8mm or the ablation zone was 8mm? What is the transition zone? What are the actual optical zone on your topographies (it may be smaller than planned one)? What was your cornea thickness before the surgery?

Pavel