Hi Jun Wei
LASIK will not worsen presbyopia ('Lao Hua'), nor will it accelerate its development.
In other words, presbyopia develops at the same rate and becomes manifest at a particular age (around 40 years of age or so) whether you had LASIK done or not.
Why so?
LASIK purely alters the shape of the cornea (the clear window at the front of your eye). Presbyopia on the other hand involves the loss of autofocusing capability of the lens of your eye. This lens is inside your eye, completely separate from the cornea and not affected at all by LASIK or any other laser refractive procedure.
Presbyopia is a much misunderstood condition, and there are endless myths about it.
But it is very simple. It is like your autofocus camera got stuck and cannot autofocus for all distances.
If you are myopic (shortsighted), and you are presbyopic, and you don't wear glasses/contacts, your eye's focus is stuck at near. So you can see near without glasses, yes, but far is all blurry until you put the glasses on. When you put the glasses on, far is clear, but near is not clear anymore. The problem is the autofocus is stuck-which is presbyopia.
If you are plano/emmetropic (neither long nor shortsighted), and you are presbyopic, and you don't wear glasses/contacts, your eye's focus is stuck at far. So you can see far without glasses, yes, but near is all blurry until you put the glasses on. When you put the (reading) glasses on near is clear, but far is not clear anymore. Again, the autofocus is stuck, this time it is stuck at far focus.
Presbyopia is caused by the age related enlargement and stiffening of the lens of your eye. It is like stuffing a pillow fuller and fuller with cotton/feathers. Your eye's lens has cells inside it that are trapped within a capsule. Over time the lens cells slowly grow and divide and have no where to go. Like the pillow that gets stuffed fuller and fuller, it gets stiffer and harder. Eventually it fails to respond to ciliary muscle contractions anymore. This process is independent of procedures such as LASIK.
There is, however, to my knowledge one paper showing apparent progression of presbyopia after LASIK: (Tsuneyoshi et al. Am J Ophthalmol 2014; 158:286-292. (https://www.ncbi.nlm.nih.gov/pubmed/24853261)
One of the likely causes of this is because people who wear glasses naturally require less accommodative effort, than emmetropes, contact lens wearers or post LASIK patients. This is explained by the thin lens formula. (Apologies, could not find a way to paste a diagram of the formula)
In this study, the authors state: 'Unfortunately, in the current retrospective study, we did not have the add power data obtained with the patients wearing contact lenses before LASIK.' In essence, if the authors had compared pre-operative add requirements while wearing contact lenses, vs post-LASIK add requirements, they may not have seen the apparent progression of presbyopia that was reported.
Therefore, there is still no evidence of a real effect of LASIK on presbyopia, that is greater than what you might see with, say, a contact lens wearer. People who wear spectacles for myopia correction, however, may notice a greater effect on their near vision after LASIK than what they had experienced while wearing glasses. But that would most likely be due to a side benefit of their glasses, rather than a detrimental effect of the LASIK surgery.
