Z-LASIK and iLASIK laser eye surgery explained

OK. lots of new laser eye surgery names appearing, so let’s confirm what they mean!

Z-LASIK: means blade free LASIK using the new Swiss Ziemer laser to make a corneal flap, rather than a traditional blade.

iLASIK: means blade free LASIK but using the American Intralase laser to make a corneal flap.

So, simple so far. Z for Ziemer’s laser and i for Intralase’s laser. Both of these devices allow elimination of a blade to make a physical cut in the cornea. Instead they use millions of precise laser pulses to create a very accurate flap, removing the potential risks associated with a metal-blade mechanical system.

Click here to watch an FDA animation of mechanical blade LASIK (N.B. Caution: watching this will put you off ever having bladed LASIK in the future! You will definitely want to opt for all laser LASIK after this!)

So what’s the difference between Ziemer and Intralase lasers?

The Ziemer laser is a new system, with potential advances upon the older American Intralase laser flap maker. Ziemer’s lasers, called the LDV, appears to eliminate occasional complications found with iLASIK. Some iLASIK patients (around 7%) get a marked discomfort and aversion to light for several days after laser vision correction, know as “transient light sensitivity”.

This side effect is not seen with Z-LASIK, possibly because of a much more tightly focused laser energy pulse and greatly reduced energy per pulse, compared to Intralase’s looser focus and wider dispersion of energy through the cornea.

Studies are ongoing to compare the two systems in greater detail.


Background on the LASIK procedure:

Creating the corneal flap is the first stage in a LASIK procedure. Treatment to correct your eyesight is actually done on the corneal tissue that’s below the surface and access to it is done by making a surface flap and folding it back (quite painlessly!).

This flap creation is critical for a successful result of your LASIK surgery – it needs to be of exactly the right thickness and in exactly the right place. When the surgery is completed, it’s easily folded back into position and acts as a delicate bandage over the treated eye. It heals up by itself.

The microkeratome devices used in traditional LASIK surgery are hand-held tools with a steel blade that oscillates, moving back and forth at very high speeds. When used expertly it makes a good flap but the thickness can vary more than laser flaps and they can be more irregular, tending to be thinner in the centre.

LASIK complications are quite rare. Fact. But when they do happen, they often arise from a poorly created corneal flap. Use of new femtosecond lasers (Ziemer or Intralase) greatly reduces the likelihood of any such complications.

»crosslinked«

Filed Under: EducationLASIKSafetyTechnology

Tags:

About the Author: Mr. Dave Allamby FRCS FRCOphth is a leading London-based laser eye surgeon. You may have seen him on the This Morning TV show with Phillip Schofield and Fern Britton or read one of several articles in the national press, recently for treating Denise Van Outen, rock giant Rick Wakeman and broadcaster Paul Ross. David is Medical Director at Focus Laser Vision, known as a world-leading clinic in the treatment of presbyopia, or age related loss of close vision. Focus Laser Vision is also London's only clinic to offer next-generation Z-LASIK laser eye treatment for short sight, long sight or astigmatism.

RSSComments (64)

Leave a Reply | Trackback URL

  1. jenn says:

    the place i wanted to get my surgery done uses allegretto wave light? is that okay? i have stigmatism and they said my cornea is shaped like a football, so they would have to reshape it.

  2. Irene says:

    Hi David,

    Are you able to advise me if I would be suitable for Z-LASIK?
    I have wore glasses since I was 8, and contacts since about 17 years – am now 29.
    My current prescription from my optician is
    RIGHT -5.50 LEFT -3.25 -1.25
    My right eye has been the same since 2007 but my left eye pescription has been different:
    2007 LEFT EYE -4.50 +0.75
    2009 LEFT EYE -4.25 -0.25
    I have recently been for a couple of laser eye consultations locally and they have my LEFT eye as either -3.00 -1.75 or -3.75 -1.50 and my RIGHT eye as -5.75 -0.25 or -6.00 -0.50
    I am seriously considering laser eye surgery and would like to have it done with FOCUS due your success rate but am worried about if my left eye has stabilised? I thought it had.
    Also I have had trouble with my contact lenses over the last 6-12 months. I have had a couple of reactions to contact lens solution and also have some dry eye problems and mild bleuphatirits. Though my optician (and the optomoterists I’ve seen at the laser eye consultations) seem to think the dry eye is from contact lens intolerance. Would I still be suitable for laser eye surgery?
    Also please could you let me know what my chances are of achieving 20/20 vision due to my prescription?
    Many thanks.
    Irene

    • Irene says:

      Forgot to add my corne thickness is around 506 microns.
      I would have to travel to London as don’t live locally, would it be easy to arrange consultation/surgery etc.
      Thanks
      Irene

    • Dave Allamby says:

      hi Irene. I think one issue here is the change in astigmatism in your left eye. It was low in 2009 at -0.25 (or -0.75 in 2007), and now is measured at 1.75D. It could relate to how long your contact lenses were left out prior to the test, if at all. I like to see a stable prescription, with only 0.25 change over 1 year. There is also progression of the myopia in your right eye, of 1.25 dioptres over 1 or 2 years (depending if your current opticians measurements were from 2010 or 2011 – not clear which it was).
      I suggest waiting and having a repeat test at the same optician in 1 year.
      Best regards
      David

      • Irene says:

        Hi David,

        Thank you for your response. I normally have my contact lenses in when going for my eyesight test with my Optician but did have them out for 24 hours when having the laser eye consultations.
        I have recently changed Optician so will wait and see what they get my prescription as when I’m due an eye sight test.
        Thanks
        Irene

  3. mike says:

    Dave
    i m 18een and unfortunately i have a high myopia -7.5 for both eyes and a thin cornea 470 so lasik is not adequate for me thats why i m thinking of having an ICL surgery so i really need ur opinion about this one and is it safe as lasik and is it Guaranteed i really dont want to lose my vision . thnxx dr
    regards
    big fan :)

    • Dave Allamby says:

      hi Mike, high prescription and thin corneas mean yes not suitable for LASIK or PRK. An ICL is a much better option than it used to be. We prefer the Starr ICL, now on its 4th version. You will be best to wait until you are 21 for the eye to slow its growth. Main long term risk is cataract, which currently happens in less than 5% of cases. This can be addressed with more surgery if necessary. Presumably future versions will help reduce this risk, which should be available by the time you are 21. WIth regards, Dave

  4. Brian says:

    Hi

    I am 54 and have -7.5 in my right dominant eye and -11.5 in my left eye with a bit of astigmatism in both eyes and about 1.5 of presbyopia.

    I have had a consultation with moorfields who have suggested that they can fully correct the right eye and partially correct the left eye to give me monovision. I have tried monovision with hard lenses and can tolerate it reasonably.

    I was about to go to moorfields but then read about laser blended vision. Is that a better option and is Focus better than Moorfields.

    Being a cautions person, I always assumed Moorfields would be the place to go but is your technology ahead of theirs ?

    • Dave Allamby says:

      hi Brian. Monovision or blended vision can be a good option for your prescription, assuming your corneas have sufficient thickness. For technology, I think that the Ziemer laser outperforms the Intralase, as used at Moorfields, and a recent study comparing the two confirms that. The Intralase market share is falling, as surgeons adopt the Ziemer Z-LASIK platform. For the excimer treating system, the WaveLight laser is my clear choice for myopia, especially high myopia.
      With best regards, David

  5. carrera says:

    dear dave
    so this is my situation :
    -myopie -8.00 for both eyes :(
    – age 18een
    and when i went to the eye doc in my area i realise that the thickness of my cornea is 481 for both eyes so the doc told me that i cant have lasik surgery or phemto-second or epi-lasik is that true and is there another solution for my condition and can my cornea get thicker by te time pls help and thnx thnx for ur help dave
    Regards

    • Dave Allamby says:

      hi Carrera
      You unfortunately have a very high prescription and thin corneas, and your doctor is correct that there is not enough tissue there to fully correct your problem. Your corneal thickness will not increase with age, sadly, so waiting will not help. Your only treatment option is an implantable contact lens (ICL). If you do this, then you will need ongoing monitoring of the health of the inner layer of your corneas each year thereafter.
      Best regards, David

  6. Allen says:

    Dave,

    Thank you very much for providing all of this insight on LASIK procedures–it’s very informative. I have heard recently that some doctors prefer EPI LASIK simply because it allows the eye (the cornea, I assume?) to fully heal, which typically leads to fewer complications down the road. Naturally there are drawbacks to this procedure as well (pain, variations in vision during healing process, haziness of vision during healing), but I was wondering if you could give your thoughts on the benefits of having the eye be fully healed afterwards, as opposed to having a flap remaining (and also potentially leaving open the possibilty of it getting snagged or otherwise injured later on).

    • Dave Allamby says:

      hi Allen. I don’t think that surface laser (PRK, LASEK, EpiLASIK) will lead to fewer complications down the road compared to LASIK, and 2 decades of LASIK hasn’t thrown up any issues for flaps long-term. We only perform about 3% of cases with surface laser now. I think you will get the drawbacks from surface laser that you mentioned but without any real gain down the line. Direct trauma to an eye, sharp trauma, sufficient to move a flap is a pretty rare event so the only time I advocate PRK for occupational reasons is for martial artists who do regular sparring to the head, and where they are not wearing boxing gloves.
      Hope that helps. Dave

  7. Dawson Richmond Sso says:

    Just wondered if the Z-Lasik machine had the anti- eye movement technology that the I- Lasik has etc if customer Px moved their eye during the procedure it would auto realign itself and continue. Thankyou

    • Dave Allamby says:

      hi. The Z of Z-LASIK refers to the Ziemer laser that is used for flap creation, and so doesn’t need eye tracking. That belongs to the excimer laser used for treating the vision problem. All excimer lasers use anti eye movement tracking technology now, so moves together with your eyes, and ensures each pulse is placed in the right location every time.
      Best regards, Dave

  8. Joe says:

    Hi Dave – i was about to do Z lasik but recently read some articles and saw videos of people that had bad experiences with lasik, not necessarily z lasik but in general.

    i obviously am a little concerned and i am wondering if you could describe the possible issues with z lasik if any.

    thanks in advance.

    regards

    Joe

    • Dave Allamby says:

      hi Joe WIth millions of treatments carried out, there are certainly some patients who have problems post-op, even things that only happen one in a million. It must always be a considered choice of benefit to risks. We do not find specific problems with Z-LASIK. The issues that come up are occasional enhancement needed, but no more than 0.5-1% of cases, which is a very low rate. You want a surgeon who is experienced with the Ziemer laser, e.g. 2-3000 cases done. Choose a clinic that has a good excimer laser, e.g WaveLight, Schwind.
      If you have a specific question, please let me know.
      Regards, Dave

      • Joe says:

        thanks Dave. i will ask them which specific machine they have as i was not aware that made a difference.

        my other concern was that this is a “relatively” new procedure and there doesn’t seem to be enough data on how this surgery can affect ones eyes as they age. i.e someone who does this surgery in their 30′s, do we know how their eyes will be affected by this at the age of 60 or 70 or older?

        thanks in advance

        • Dave Allamby says:

          hi Joe
          Its an interesting point. I believe that with more than 20 years of laser eye surgery experience, we now know how the eyes respond long term, and there aren’t any problems surfacing late on. I don’t see a pathophysiological process that would induce very late changes. I think it will also come down to preference, and feeling towards early or late adoption. Some people will want e.g. 50 years of follow up before going ahead, which is fine, and this is always a personal choice and not an essential procedure. It will come down to the individual, although I do not believe we will see any late issues whatsoever.
          Regards, Dave

  9. Becky says:

    Hi Dave,

    I’m looking to get laser eye surgery in the USA. I have decided that I definitely want Z-lasik and I have found two very reputable doctors in my area that use Z-lasik. Their differences, however lie in the laser they use for vision correction. What excimer laser is the best out of these three: Alegretto Wavelight 200 HTZ, B & L Zyoptix, or VISX Star S4? Thanks for your help.

    • Dave Allamby says:

      Hi Becky, interesting question. It will depend on your prescription. Can you give me the approximate numbers? thanks Dave

      • Becky says:

        The prescription from my contact lens box reads: right eye pwr -2.00 -1.50 x 110 and left eye pwr -1.00 -1.50 x 70. I also have an astigmatism. Thanks again for you help.

        • Dave Allamby says:

          Becky, Thanks. with your relatively low prescription (by my terms!), you can safely go with either the WaveLight or VISX S4 lasers for your Z-LASIK. Both will do well. Make sure you get the CustomVue treatment if you go for the VISX, which is necessary to get the best results on that machine. WIth the WaveLight a wavefront optimised procedure will give excellent results. Final choice will always be down to the surgeon who will perform the op, once you have narrowed down the the right lasers.
          Regards, Dave

  10. carrera says:

    HII Doctor
    i m 18een and today i went to an eye doctor and i found that i have -7 to both eyes (myopia) and its the same since one year and i really want to have a lazik surgery so i came to u to advice me and tell me if i can have it tthnxxxx

    • Dave Allamby says:

      hi Carrera
      Yes, you may be suitable as your prescription has been stable for 1 year. It will depend on other factors such as corneal thickness, pupil size at night, etc. Book for a consultation at a local eye clinic and they can advise you.
      Regards, Dave

  11. zlasikrocks says:

    Hello Dave,
    i am mailing from Canada, we don’t have z-lasik here. Can i come over in UK to do z-lasik and fly back after the surgery?
    is there any complication for flying after 1-2 days of surgery? I am 28 ,and my eyes are minus 5. How much approximately it will cost for me for z-lasik? Also how i will go for the post-surgery check-ups?

    Give me your valuable suggestions.

    • Dave Allamby says:

      Hi. Thank you for your email. Flying after Z-LASIK is not a problem. You would want to be here for a few days for the 1 day check then review say 3 days after to give you the all clear. Those are the most important safety checks to rule out infection, inflammation, etc. We normally review once more at 3-6 months for routine cases to confirm the prescription at zero, and you could get get this done locally. Needing an enhancement is rare, around 0.5% at our clinic for this prescription. Treatment fees for -5.00 both eyes are £3250 for Z-LASIK. Please let me know if you have any other questions.
      Best regards, Dave

    • Erin says:

      We do have z-lasik in Canada. I will be getting it done in a few weeks. The cost is $4200 for both eyes and it is done in BC

  12. Kevin says:

    Hi Doctor,

    Would you please advise if “zlasik” is still better and newer technology compared to “ilasik with iFS Advanced Femtosecond Laser”?

    Thanks

    • Dave Allamby says:

      hi Kevin, I prefer the Ziemer system (Z-LASIK). We have the brand new Ziemer LDV Crystal Line system, and it is a remarkable flap creation too. It is 33 times faster repetition rate than the latest iFS 150KHz model, with energy per pulse far lower, tighter energy focus and the shortest suction-on time. We can do both eyes safely and very accurately in around 6 minutes.
      Best regards, David

      • Kevin says:

        Hi Dave,

        Thanks for the reply. However I am still confused with the surgery in my area that offer me the z-lasik and ilasik.

        One place only offer me the ilasik which cut the flap by using intralase with iFS Advanced Femtosecond Laser, and use VISX Laser.

        However, I am not to sure with the place that offer me with both z-lasik and ilasik. They said that they use ziemer to cut the flap (which is using (intralase femtosecond) and using excimer laser. For the ilasik, it seems that they are using intralase but not VISX Laser, instead they use allegretto wave which made me more confused.

        Please let me know which one is better?

        Many Thanks

        • Dave Allamby says:

          hi Kevin
          Z-lasik means using the advanced Ziemer femtosecond to create the flap, with vision being corrected by any excimer laser. iLasik refers, as you say, to a procedure with an Intralase brand femto and a VISX laser to correct vision.
          The best option for me is using the Ziemer femto with the Allegretto Allegretto Wave excimer laser. If you cant get that, then the Intralase femto to create the flap, plus WaveLight Allegretto for vision correction would be my next choice.
          Best regards, Dave

          • Kevin says:

            Hi Dave,

            So you value Allegretto Wave higher than VISX 54? And is this better in any type of eyes? Such as astigmatism / short / long sighted / night vision?

            And just to double confirm, from your last reply, are you referring the term of Allegretto Wave excimer laser and WaveLight Allegretto as the same?

            Sorry I asked lots of question

          • Kevin says:

            Hi Dave,

            So you rate Allegretto Wave higher & better than VISX? Is it better for any specific type of eyes? Or generally better for astigmatism / long / short sight / poor night vision.

            Also, on your last reply, do you refer Allegretto Wave excimer laser and WaveLight Allegretto as the same thing?

            Many thanks

          • Dave Allamby says:

            hi Kevin
            Yes, I rate the Allegretto as better than the VISX for all prescriptions. The VISX performs well for short-sight up to -6 dioptres, almost as good as the WaveLight. Above -6D the VISX performance falls away compared to the WaveLight platform.
            The WaveLight company is based in Germany. They first produced the Allegretto Wave laser with a 200Hz speed. Later came the improved Allegretto Wave Eye-Q laser running at 400Hz and with other improvements. You want to be treated on the faster Eye-Q version. With this laser, combined with the Ziemer LDV Crystal Line femtosecond laser to create a Z-LASIK flap, we achieve 100% of patients with 20/20 or even better, even up to high myopia.
            With best regards, Dave

          • wayne says:

            dear dave,
            as you compared laser platforms,how does the latest zyoptix rate in relation to the eye q for low to moderate myopia
            thanks

          • Dave Allamby says:

            Hi Wayne, hard to say actually as we are lacking good comparative data. Ultralase currently claim 99% achieve binocular 20/20 at 6 months for their latest B&L, and OE claim 98% with the VISX platform. We get 100% to 20/20 with the WaveLight Allegretto Wave Eye-Q 400Hz plus Ziemer LDV for the same myopia treatment range.
            Regards, Dave

  13. carrera says:

    hi doctor
    i m 17 and i will 18 in about 10 months an i want to have LASIK surgery this summer what can u advice me
    thnx

    • Dave Allamby says:

      Hi Carrera
      You should have a sight test now and again when you are 18. If there has been no change, no more than 0.25 dioptres increase, then you could be eligible for surgery at 18. If it has increased by 0.50 or more, I would wait and recheck when you are 19.
      With best regards. Dave

  14. Albert says:

    Hi Dave,

    just wondering if normally Z-Lasik can fix myopia up to -9 if cornea thinness is not an issue here??
    is there big chances on getting halo/bad vision during night time after doing Z-Lasik?

    Thank you

    • Dave Allamby says:

      hi Albert
      Treating myopia up to -9 isnt a problem in itself, assuming the pupils aren’t huge. If you get some halo or glare at night time now, you may well still have it post-op, typically to a similar degree. You may well have some night glare during the first few months, which will gradually lessen, but which isn’t usually problematic.
      With best regards, Dave

  15. Paul says:

    Hi Dave,

    My girlfriend has just been for a consultation today with a view to undergoing laser eye surgery. Unfortunately owing to her long sighted vision being +5 in her right and +6 in her left eye she was informed that she is unsuitable for surgery. I realise that the tools used in corrective surgery (like most things technology related) are continually being improved and developed. Are there any advancements being planned or tested that will eventually mean she can undergo laser treatment?
    Kind regards

    Paul

    • Dave Allamby says:

      Hi Paul
      Depends on her age. If she is young there isnt anything I could recommend now or in the near future. If 40+, then lens implants (refractive lens exchange) can rectify the problem.
      Best regards
      Dave

  16. andri says:

    Dear Dave,
    i just consulted with a doctor about lasik, i think i prefer Z-lasik, but the doctor said my cornea is too thin for Z-lasik, so he recommend i-Lasik for me. Is it true? I think Z-lasik is the latest technology compared with i-Lasik, but why Z-lasik required thicker Cornea?

    Thank’s alot for your explaination,

    Regards,
    Andri

    • Dave Allamby says:

      Hi Andri
      That makes no sense whatsoever. Z-LASIK can cut down to 80 micron flaps which is thinner than you would ever want to go, and as thin as i-LASIK flaps.
      Regards, Dave

      • Matt O says:

        Hi Dave,

        Just jumping on this thread as it relates to my question:

        Optimax told me my cornea is too thin for laser surgery and i have to have ICL. I immediately dismissed this and was depressed for a few days. I am 36 and have worn glasses since 1 was 7 years old.
        I have since found out that they only do Lasik and ICL…
        My question is: will z-lasik be able to operate on thin cornea patients better than i-lasik?
        Should get a second opinion for maybe LASEK?
        My prescription is -7.00 and -6.50 and 0.50 astigmatism in the left eye. I have not received my pachymetry details from Optimax, so can’t say precisely about how thin my lenses are. Would you recommend z-lasik? and how much would it be if you did.

        Thanks

        • Dave Allamby says:

          hi Matt
          Please can you find out your pachymetry measurements and also your pupil size diameter in the dark. They will have measured both of these at your Optimax consultation.
          Thanks, Dave

  17. Chris says:

    I had Lasik done in 2001 using the blade flap. I was told some years later when I went back asking about getting a touch up performed that re-opening the flap isn’t a good idea.

    Now my distance vision is getting poor so I’m considering a second Lasik procedure.

    What are my options for getting Lasik done a second time?

    I also read a second Lasik procedure can correct the night time halos some people experience, is this correct?

    • Dave Allamby says:

      Hi Chris
      Technically you can re-lift an old blade flap but it isn’t a good idea as can lead to complications. Recutting a blade flap can sometimes lead to worse optics so we generally do don’t do that. There is ongoing research into recutting a flap using a femtosecond laser. However, you would be better having a PRK procedure for an enhancement at this stage, and using mitomycin C to prevent haze.
      Regards, Dave

  18. Syaifullah says:

    Hi Dave,
    You said that the mechine of zlasik is more expensive than ilasik, but why in Indonesia, the cost of zlasik is more cheaper than ilasik? Could you recommend me about what kind of lasik and clinic in Jakarta. Thks & regards, Syaifullah

    • Dave Allamby says:

      Hi Syaifullah. Pricing will vary between clinics, technology, service and with the experience of the surgeon, which is very important, so the cost is not just on which machine is being used. Sorry, I am not familiar with clinics in Jakarta, but use the principles I have written about on how to choose a clinic, in several previous post. Click on the Clinics tab and you can see all my posts there.
      Best regards, Dave

  19. Edwin Lam says:

    Hi, my girlfriend is planning to do lasik in hong kong and the hospital said it depends on the diagnose on whether she can or what type of lasik she can do. They said they will use the latest lasik to treat her if she meet the requirments. And she said the latest type is Intralase, but all over the web I have found a newer type call z-lasik which is also described above.

    Would you please advise on the differences between the 2 technique?
    Are there any big disadvantages using the Intralase technqiue?

    A Million thanks in advance!

    • Dave Allamby says:

      Dear Edwin
      These are two types of femtosecond lasers – one is the Intralase from U.S., and the other the Ziemer from Switzerland. Both systems will cut a good corneal flap so there is no big disadvantage, and both preferable to a blade cut. You can safely go with the Intralase where you are. I prefer the Ziemer laser for LASIK (when it is called Z-LASIK) over the Intralase, and chose Ziemer for my clinic, even though the more expensive.
      Best regards
      Dave

  20. Jen says:

    I am considering LASIK. I live in USA so was going to go for ilasik until I heard of zlasik ( i’m from UK and would travel back to have zlasik if it’s better). In USA they also offer wavefront technology with ilasik and I wondered if that is available in UK and also is it worth it?

  21. A.K. Sethi says:

    When you say both iLasik & Zlasik are bladeless technique, then why should one go in for z-lasik? what are the advandages of zlasik vis-a-vis ilasik?

  22. Manish says:

    Hi Dave,

    What do you mean by “choice of treating (excimer) laser and size/type of prescription. Zeimer is not available in my area as well. I was planning to go for i-lasik. However, reading about the complications like eyes getting dry and ofcourse “transient light sensitivity”, I just feel that I should wait for Zeimer. Please suggest.

    Regards,
    Manish

  23. Brian says:

    Dave,

    Z-LASIK is not offered in my area. However, IntraLase LASIK is. Are there any long-term differences in the end result between the two? I’m wondering if it’s perfectly alright to go ahead with iLasik, or is it worth waiting for Z-LASIK to become available?

    Many Thanks,
    Brian

    • Dave Allamby says:

      Brian
      I think both the Intralase and the Ziemer femtosecond lasers will do a good job for a blade free flap. The bigger question is the choice of treating (excimer) laser and the size/type of your prescription.
      Regards
      Dave

  24. Irene says:

    Hi David,
    Sorry I forgot to add if you could answer with cornea thickness of around 506 microns if I would be suitable for ZLasik or would I be better off with LASEK?
    Thanks again.
    Irene

Leave a Reply

Rss Feed Technorati button Reddit button Myspace button Linkedin button Delicious button Digg button Stumbleupon button Flickr button Facebook button Tweeter button Youtube button