Contact lenses

[potholer]

I understand that even when laser surgery works fairly well, poor night vision is a quite possible downside.
(I'm no optician, but I *think* it's due to the iris being wide-open in darkness, and either something to do with the treated area being relatively quite small, or simply an effect of the enlarged aperture showing the optical defects at their worst.)

In any case, if poor night vision is a possibility, cavers should presumably be a little more wary than the average person.
Getting expensive laser surgery done specifically for caving and then still having to wear corrective lenses (if they make things any better) could be galling at best.

 

[ian mckenzie]

Laser can sometimes result in a 'halo' effect around lights at nighttime, making driving difficult. One would imagine your caving would also be affected. As well, people forget that eyes still continue to age, and normal deterioration can be expected over time, altho some doctors offer free 'touch-ups'.