DAVOD responds to my first question:

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Severe night vision problems" implies an optic zone that is smaller than the dark adapted pupil. 20/20 implies that the optics overlying the ablation zone are fairly regular (i.e., without significant aberrations).

Lifting and suturing the flap would alter the central flap dynamics, essentially where you are NOT having the problem. If your surgeon does not know whether this will help the night vision problem, then it seems rather pointless and potentially risky to your otherwise good acuity.

If your night vision problems are abated with Alphagan (brimonidine) or a weak concentration of pilocarpine, then pupil size is more likely the issue.
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I have a 2-3 second tear break up time. The doctor said this may be due to the irregular corneas with high and low spots. Lifting the flap is an attempt to smooth the cornea. Even if smoothing the cornea does not fix the night vision problem, I'm still interested in the procedure in hopes of improving the TBUT enough to allow RGPs.

I've tried different remedies to improve the TBUT: Heat, tetracycline, cyclosporine. None of it helped significantly. Right now I can only tolerate the RGPs a couple hours a day. I have three pairs of lenses, each from a different OD. The newest set came from an OD who specializes in refractive complication remedies. Although these lenses are the most comfortable, they do not allow more wear time.

I use dilute pilocarpine and it does shrink the starbursts. Not nearly as well as the RGPs, however.

So has anyone had a flap lift specifically to improve TBUT?


TIA,

Kevin

Kevin,

The "high and low spots" on a post-rs cornea are not necessarily coincident with the points on the cornea where tear breakup occurs. While certain visible epithelial defects may fail to wet consistently following each blink, in most cases the points where early breakup occur are random. Further, significantly steepened areas of the cornea easily identified on topographic images do not exhibit early breakup times. Generally, there is no pattern to tear breakup that would represent the underlying topography.

It is not unusual to see a successful exended-wear contact lens patient (overnight user) whose tear breakup time is markedly reduced. The argument is that the soft lens mats down the normal "irregular" epithelial surface, a surface designed to hold the tears in place. People seem to forget about the cornea's natural ability to hold the tears. Does LASIK alter this natural, tear-holding property? I don't know. This is only something that can be observed in tissue sections under a microscope. Does an extended wear soft lens actually smooth the surface or is the smoothing the result of low grade tissue swelling? Again, I don't know. Lifting and stretching the flap is not likely to smooth the cornea on a level that is this microscopic. In other words, without some supporting study, I would doubt if the TBUT will be altered.

BTW, patients who remove their extended wear soft lenses do not experience sudden dry eye. While tear breakup may correlate with dry eye symptoms, other factors no doubt are at play.