My Experience with LASIK: Observations, Comments, and Thoughts
Legal Notice: I am an engineer, not a physician or other health care professional. What you see here should not be construed as medical advice and should not replace consultation with a qualified physician. I have attempted to provide a reasonably objective account of my own individual experience with LASIK. I have also made an attempt to separate my own opinions from more quantitative observations. My purpose in providing these materials is to provide others who are considering the LASIK procedure more complete information than I was able to obtain when I decided on my own procedure.
My procedure was done at: LCA Vision Center (now known as
Dr. George V. Simon
1390 Willow Pass Road, Suite 540
Concord, CA 94520
I wish to note that Dr. Simon is distinguished from his colleagues by a number of factors, but some of the most notable factors were his high level of experience in terms of the number of procedures performed, his willingness to perform a comprehensive eye exam without cost or obligation, and having an unusually knowledgable non-OD/MD staff.
The equipment used was a VISX Star S2 Excimer Laser.
I started at about -9 diopters in one eye and -8 in the other with mild astigmatism(~1.25 cylinder) in both.
My procedure was done on
The Actual Procedure(posted
I arrived at
My night vision remains significantly impaired though it is possibly improved from the second evening after the procedure. I still see moderate to moderately severe halos around light sources, particularly street lighting(mercury lamps) and oncoming headlights. It is quite distracting and my night vision is definitely significantly impaired. I tried yellow polarized sunglasses, but found they offered minimal improvement.
As of now(
I was told that I was seeing 20/30 24 hours post procedure according to the big "E" Snellen eye chart. However, I now consider the Snellen eye chart to be a less than comprehensive assessment of refractive surgery results. For instance, it does not quantify visual distortion such as the halo effect or measure visual acuity under different lighting conditions. In my view, it is only a very rough estimation tool at best. Despite this, it remains the primary assessment tool and most, if not all, the LASIK and other refractive surgery statistics are based on measurements made using it.
I have concerns about the possibility of off center ablation. From the videos, it is apparent that the laser was generally centered on my pupil during the ablation process, but it is also apparent that there was noticeable jitter or movement. I am uncertain as to the significance of this at this time as I have to yet to find research and/or studies addressing this issue.
From my research, the VISX Star S2 Excimer Laser currently provides the smoothest and most uniform surface post-ablation. Though it seems logical that a smoother surface would yield superior optical and healing qualities, that remains, to my knowledge, unproven by reputable studies. The lack of a computerized eye tracking system in the VISX Star S2 system may be a limitation, but I think that the multi-beamed nature of this system somewhat mitigates the lack of a computerized eye tracking system. Note that the only computerized eye tracking Excimer Laser for refractive procedures I am aware of is not currently FDA approved and is currently undergoing human trials. However, I believe the laser(a small spot raster scan type) used in this experimental system is different and possibly inferior to that used in the VISX Star S2.
For the curious, the lasers used in LASIK and PRK are called Excimer Lasers because the gas inside the laser tube is generally a compound known as ArF, a substance that is in a class of chemical compounds known as excimers. Lasers with excimer gases, particularly ArF, emit a relatively short wavelength UV(ultraviolet) light which contains sufficient energy to vaporize certain materials(such as corneal tissue) without significantly heating the surrounding areas. UV light at these wavelengths is generally not visible however.
The halo effect has not significantly diminished since the first day post procedure. My last eye exam on
It has now been about a month after my procedure was done. My general vision remains good with the exception of night and low light vision. The halo effect remains essentially unchanged since my last entry on
I went in for my post one month checkup on
My next checkup is scheduled in January 2000.
I have added a detailed narrative of my LASIK experience before, during, and immediately after the procedure. Though I have no major complaints about my procedure at this time, it is interesting to note that my outcome was considered optimal. By my standards, I would characterize my outcome as acceptable, but not optimal or perfect. However, since since my outcome is considered optimal, it is clear that the accepted standard of "optimal" for LASIK procedures is significantly lower than one might be led to believe based on the common LASIK literature and patient information. In a nutshell, obtaining 20/20 or better vision in each eye with no side effects(such as halos in low light conditions) is not a probable outcome though achieving an acceptable result with some minor tradeoffs is highly probable. My own individual experience, at least to date, is the latter.
I noticed that my distance vision seems to have degraded slightly so I went for an unscheduled checkup on
It has been more than four months since my procedure was done. My vision with both eyes remains at 20/20 and appears to be stable, but I still see mild, though clearly noticeable, halos around light sources in low light conditions. The condition is not what I would consider to be debilitating, but I notice it often and it remains a frequent reminder of the limitations of the LASIK procedure. My current vision is generally comparable to my vision corrected by glasses except in very low light and/or night conditions. At night, I can still drive and function without significant restriction, but the visual distortion(halos) remain noticeable. The effect is distracting and represents what I would consider to be a significant degradation in my night vision compared to my night vision corrected with glasses before the procedure. In general, I would say that I am reasonably satisfied with my results to date. But, I want to emphasize that I do not consider my results to be perfect, but I think the tradeoff to be a reasonable one.
I also wish to note that this LCA Vision is now Lasik Plus. This facility located in Concord(CA) is now flooded with new patients and prospective patients, presumably as a consequence of the massive advertising of the new $2995 pricing. As a consequence, I would have significant reservations about having a procedure done at this facility without thoroughly investigating their quality control procedures and standards. Having this volume of procedures often entails significant degradations in quality control unless extremely stringent quality control standards and procedures are enacted. Even with strict QC standards, the doctor and other personnel operating the equipment may become tired and produce less optimal results. (You may recall that the doctor manually operates the microkeratome and lifts the flaps, as well as manually aiming the laser.) For my most recent checkup, I waited about 45 minutes before I was seen by an optometrist even though I arrived well in advance of my scheduled time. This is a significant departure from previous visits prior to their name change.
My vision continues to be good about 10 months after the procedure. It is now about 2 months before my scheduled 1 year checkup and my vision remains very good at 20/20 or near 20/20 vision with both eyes. My left eye, judging from the small display on my VCR, appears to be slightly worse than my right eye, but still very good. This slight degradation in the vision in my left eye was first noticed about 6 month ago and appears unchanged since then. The halo effect however is still present and unchanged since at least 6 months ago. It is mildly distracting at night and occasionally indoors, but is not debilitating. I would regard it as a minor annoyance at this point and a worthwhile tradeoff in exchange for the overall improvement.
I had my one year checkup today and the results are generally good though I do have some concerns since my vision apparently has degraded slightly according to the eye tests. I have not noticed any difference in visual acuity during my normal activities however. My right eye is still considered to be 20/20, my left eye is 20/25, and my combined vision is 20/20. However, those numbers may be deceptive as I am now -0.75 diopter with +0.25 cylinder astigmatism in my right eye and -0.50 diopter with +0.5 cylinder of astigmatism in my left eye. For reading text at a distance, I have noticeably better acuity in my right eye. At this exam, the optometrist also noticed a trace of haze in the laser ablated area of my right eye though I do not notice any visual distortion or other effects from it at this time. While I am unable to see this haze in a mirror, this is a change that concerns me and that I will monitor very closely. But, all indications are that it is not and will not become a significant problem. At this appointment, the waiting room was empty and I was seen quite promptly despite arriving about 10 minutes early. (The center has also hired additional staff though their physician staff remains unchanged.)
I should also mention that there are a number of new and/or improved LASIK variants being developed and some currently in clinical trials at this time. There is at least one variant that incorporates a computerized eye tracking/aiming system and another that has an extended laser ablation area. The old version corrected only a 5.0 mm area, the successor corrected 6.5 mm which is the one I had, and the latest version is supposed to be in the 10 mm range. This should reduce the halo and visual distortion problems experienced when/if the pupils dilate to beyond the corrected area. However, there may be significant consequences of ablating such a large area. In comparison, the area of a 10 mm circle is about 2.4 times that of a 6.5 mm circle. And, since the area in question is actually a sphere instead of a circle, the difference is actually even larger. I believe it would be prudent to closely scrutinize data about the effects of these changes before making any decision as the fairly solid collection of evidence recommending LASIK is only directly applicable only to the 5.0 mm ablation sized variant and may not necessarily apply to the 10 mm version. In addition, other effects, which may not be significant at 5.0 mm or even 6.5 mm size, may become significant when the ablation zone is enlarged to 10 mm.
Finally, contrary to what some developers of the LASIK equipment may claim, I believe that the skill of the ophthalmologist performing the procedure remains a significant factor in determining the outcome. The procedure is not as automated nor as repeatable as some may wish us all to believe. At this time, LASIK is still not something to be done casually though the majority of outcomes is good and will likely continue to improve in the future with better technology. It is unfortunate that some of the recent LASIK advertising could be considered deceptive. With pricing now advertised in the $2000 range for both eyes, the message I have seen advertised is that LASIK is just a more economical and convenient alternative to glasses or contacts. What is left unmentioned is that the results are permanent and typically imperfect. With our current technology, there is no way to reverse the procedure. As of now, I am one of the many who enjoy the benefits of a generally successfully procedure, but there are a significant number of patients that did not fare so well. Though the probability of an undesirable outcome is relatively low, I think it high enough to justify careful consideration before deciding on this procedure. If, for example, your work or daily activities require a high level of visual acuity which you presumably have before the procedure with the aid of corrective lenses, you may wish to carefully consider the possible consequences of having reduced visual acuity or the introduction of visual artifacts, particularly at night or in low light conditions. These post-LASIK conditions may not be correctable, are usually permanent, and you may have to restructure your work and activities to accomodate them. I do not intend to unduly frighten those interested in the LASIK procedure, but wish to bring attention to these important considerations. To temper these warnings, I should emphasize that these problems occur relatively rarely, perhaps in the range of a few tenths of a percent. But, these problem cases are not typically well documented in studies or literature as the "20/20" visual acuity numbers typically quoted do not directly address these issues.
I have scheduled an appointment with my regular optometrist and will provide the data and conclusions from that examination when it is completed in approximately 1 week.
I had my eyes examined by Dr. Richard Chong(my regular optometrist for the past 20 years) on
The comparison of visual acuity measurements is as follows:
LEFT EYE RIGHT EYE
0.00 Diopter -0.50 Cylinder *
-0.25 Diopter -0.25 Cylinder *
-1.00 Diopter -0.75
-0.50 Diopter -0.50 Cylinder
Dr. Chong -1.00 Diopter –0.50 Cylinder 0.00 Diopter –0.50 Cylinder
(*The LASIK Plus measurements have been converted to the notation used by
Dr. Chong for easier comparison and is from my last exam at Lasik Plus on
As may be evident from this data, the Lasik Plus Data is significantly different from Dr. Chong's measurements. The difference is entirely unfavorable though I would also emphasize that I consider my vision to be good at this time and I do not have any need to wear glasses or contacts. My most significant problem has been and continues to be mildly to moderately impaired night vision.
I have not noticed any change in my visual acuity. A routine checkup
by Dr. Richard Chong on
I have not had a regular eye exam for about 2.5 years, but my vision appears to have deteriorated slightly though it still remains good overall. I would estimate my current overall visual acuity with both eyes at somewhere between 20/25 and 20/30. While I could read the VCR display from my sofa 2.5 years ago, the small digits are now blurry enough to be nearly unreadable (at least without guessing.) As before, vision in my right eye is noticeably better than in my left eye. I have not noticed any additional visual artifacts though the mild halo effect about point source lights remains.
My vision is unchanged and remains good overall. I did notice that I can read small print/type more easily with my left eye than my right. This is probably due to my left eye being farther from 20/20 than my right eye. (I have better distance vision from my right eye.) This outcome was not planned or intended at the time my procedure was done, but perhaps it will work out well when I get older. Maybe I’ll even be fortunate enough to not need reading glasses in 10-15 years. (I turned 35 this year.)
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