Can You Have Regular Lasik and then Change to Mono Vision Lasik?

Yes, but consider trial contact lenses to be certain that you understand the post operative results/outcome.

As people age, they lose the ability to focus up close.  By the time that most individuals are in their mid forties and have good vision for distance they will need glasses for reading.  Just like someone who was born with naturally good vision for distance, those with LASIK are in the same situation.  Monovision can be a great solution for some people.  In my experience about one half of people enjoy monovision and the other half don't.  Testing can be done to determine who would be a good monovision candidate.  If the previous LASIK was in the last few years, most surgeons would consider lifting the flap and add the treatment needed for monovision.  If LASIK had been done more than a few years previously, few surgeons are comfortable lifting such flaps.  Several options are still available with present technology.  One would be Surface Ablation also known as PRK which uses the same laser as LASIK but does not involve lifting a flap.  This is a great solution because it is a permanent change to the cornea.  Conductive Keratoplasty (CK) is a very different technique where a probe touches the cornea 8 times in a ring shaped pattern which causes shrinkage of the corneal collagen and a steepening of the cornea.  The nice part of CK is very fast healing.  The downsides include that it is not permanent.  Former LASIK patients tend to have a better response to CK and non-LASIK patients.  The other problem is that many surgeons do not have access to this technology.  Alternatively a lens could be placed in the eye to give reading vision.  When I wanted to have reading vision, I first chose CK twice and then went to LASIK for a permanent fix so that I could have reading vision.

It depends on many things whether having another LASIK procedure for monovision is a good idea.  If the original LASIK was many years ago (as I suspect) then you run a much higher risk of complications having it done again for monovision.  Specifically, the risks of epithelial ingrowth which is when a layer of the skin of the eye grows under the flap can be problematic.  In general it is best to decide what the refractive goal is and not make a later change.

You can usually have an enhancement to perform monovision LASIK after Distance LASIK.  If there is not enough corneal tissue, another laser vision correction may be possible, known as Advanced Surface Ablation. 

In monovision LASIK or PRK we leave the non-dominant eye a little nearsighted in order to allow comfortable reading with that eye. The other eye is corrected for distance vision. This procedure is only performed on patients in the presbyopic age group, typically above the age of 40. Before inducing monovision surgically I always have my patients try it out first with a lengthy contact lens trial as this can help avoid the situation you are in now.

The good news is that you can have the nearsighted or reading eye corrected for full distance vision which would eliminate your monovision situation. The bad news is that you will immediately need reading glasses to see up close, so be absolutely sure that you have given it enough time to fully evaluate it. I would recommend trying it for about 4 to 6 months before undergoing another surgery to reverse it.

If you had LASIK at age 30 and now you are 45 and starting to have some difficulty reading, it is possible to perform an enhancement to create monovision. There are a few things to look at first, however. Is there enough remaining corneal tissue to allow for a safe retreatment(your surgeon can tell you this). Second, will this treatment improve your near vision enough to make it "worth it".....your surgeons office should be able to show you, via an eyeglass or contact lens trial, what your result will be like so that you can make a good decision. Lastly, will you still need reading glasses to some degree.....typically, monovision is performed in just one eye, which means your uncorrected reading vision will be much improved, but you still may need readers occasionally for very small print. All of these issues, and more, should be addressed by your surgeon.

Yes, this is possible IF corneal thickness permits.  Also, I would recommend a contact lens trial of monovision first, to make sure that you like that type of vision (about 90% of patients like monovision).  It would not be good to do monovision surgically with a second procedure, then find you don't like it, and have a third procedure.