Hear an interview with Dr. Stephen McLeod, a specialist in laser vision correction surgery, and patient Vanessa Chiu, who has 20/20 vision after LASIK eye surgery.
Photo by Tom Seawell
Vision problems can affect your life in a big way, not to mention the annoyance of keeping up with glasses and contacts. In this program Dr. Stephen McLeod will talk about the benefits and risks of laser vision correction surgery and the latest technology for the surgery. You'll also hear from his patient, Vanessa Chiu, who had that laser surgery just three weeks ago. It's all next on Patient Power.
Hello and welcome to Patient Power sponsored by UCSF Medical Center. I'm Andrew Schorr. On our program, we talk about all sorts of conditions. One condition that affects literally tens of millions of people is vision problems. Some people are nearsighted, some people are farsighted, some people have astigmatism, and have to wear glasses or contacts. In the last few years, we have had laser surgery and those laser surgeries have gotten better and more available for people with more types of vision problems. But it's not for everybody. If it is right for you, you can literally throw your glasses away.
One person who is celebrating that is Vanessa Chiu, from Walnut Creek, Calif. She actually works at UCSF. What happened three weeks ago, Vanessa?
Well, three weeks ago I had LASIK eye surgery, and now I can see without glasses and contacts.
Let's go back to about, I guess you were age 16, when your vision started to deteriorate?
Yes, so starting at the age of 16, I started wearing glasses and contacts.
That was something you just have to live with, I guess. Even with contacts, there's maintenance that goes with that. That can be a pain.
Yes. It's very bothersome, and it can get uncomfortable, too, throughout the day.
So you had to wait a couple of years.
So that your vision was stable?
Yes, my vision has been stable for the last two years now, so this is the first year that I was eligible to be considered for laser eye surgery.
As we'll learn, doctors don't want to make a correction until they know where the eye is and where it's going to be, so they know what to correct. These are just minor changes that they make can make a big difference. How is your vision now?
My vision is great. I have 20/20 vision now. I can see far away without glasses and contacts, and I'm able to drive and see everything just perfectly now.
Wow. No correction needed. I understand that you timed all this so two weeks after surgery, you could go to Mexico, to Cabo, with your boyfriend and his family and go swimming and in the hot tub and all that. You cleared for all those activities, am I right? And enjoyed it without contacts and taking all that in your suitcase?
Yes, that's correct. I was able to celebrate my new corrective vision with a vacation in Cabo.
Just a little bit about the procedure itself. So was it a big deal?
No. The procedure was painless, and it was very fast. Dr. McLeod and his staff, they tell you exactly what's going on and what's happening so that you don't have to be anxious at all.
And the recovery, is that difficult?
No, not at all. There's just a series of eye drops that you need to take after the surgery, but other than that it's pretty much in and out.
Well, we wish you well with your new, improved 20/20 vision and not having to deal with glasses and contacts. We'll hear or more from you shortly. But let's meet your doctor. That's Dr. Stephen McLeod. He is not only your eye surgeon, but he's the chair of the Department of Ophthalmology at UCSF. Dr. McLeod, to hear Vanessa and how happy she is must make you feel great as her surgeon.
Oh, yes it's always gratifying to see these patients who have had to rely on glasses and contact lenses for so long, be able to do all of their daily activities without glasses and contacts lenses. The liberation is always very, very gratifying.
So, Dr. McLeod, let's understand where we are with the state of the art now with laser correction for someone's vision. I know the techniques you have, the technology you have has expanded. Tell us about that. Who can be helped?
Yes. The technology has expanded a great deal since these procedures were first approved by the FDA in the mid 90s. And essentially, when these procedures were first introduced, they really could only be applied to people with nearsightedness with a relatively low degree of astigmatism. But over the years the treatment algorithms and the laser technology and in fact the LASIK flap creation devices have all been advanced to the point that the vast majority of individuals who have the need for glasses and for contact lenses can be considered for surgery with these devices.
Certainly there are individual conditions that make it very important for us to perform individual examinations to decide whether or not they are good candidates. But the range that we can treat now has been broadly expanded.
Let's talk about that for a minute. So if someone is nearsighted, that means they have difficulty seeing things that are further away, right. If they're farsighted that means close up is more difficult. And then we have astigmatism as well.
That's correct. So essentially the initial procedures really just addressed nearsightedness without astigmatism. Now, we're able to change the shape of the cornea to improve nearsightedness and astigmatism, and there are some degrees of farsightedness that we're able to correct as well.
Now, what if you have, some astigmatism and either nearsightedness or farsightedness? Is that too complicated to fix?
No, not at all. In fact, one of the advantages of the systems is that most of the more complex refractive surgery laser systems can correct not just the astigmatism and the nearsightedness. We're able to use systems called Custom or WaveFront systems to measure what are called higher order aberrations, aberrations in the eye that even glasses aren't able to address.
The lasers are able to reduce those aberrations in the eye, so we've been able with the most modern platforms to go beyond just nearsightedness and astigmatism.
Did I hear this right, though, that maybe there can be correction with a precision with a surgery that you can't do with glasses?
That's correct. When you have a pair of glasses, the glasses can only correct refractive errors in a way that is perfectly symmetric. It can't do a different correction over one part of the cornea than the other.
With the modern laser systems, we're able to do these custom measurements where we image the specific pattern of aberration that we see in an individual's eye. That gets programmed into the laser and so a very specific pattern, that may in fact be quite asymmetric, can be programmed into the laser for correction.
Let's understand the basics of surgery, and then we'll go back and understand who might or might not be a candidate. When someone is having laser surgery on their eyes, I know there are different techniques. What's the typical approach, and then what are some of the variations?
Essentially, the way to think about all of these procedures is that we're using the excimer laser to reshape the surface of the eye so as to change the focusing power of the cornea. From that point, we can recognize there are a number of different ways that we can to this. One way is to just apply the laser energy directly to the surface of the eye. That's the so-called PRK or photorefractive keratectomy.
The alternative is to use an instrument called a microkeratome, or an IntraLase laser to create a LASIK flap. That is lifted off of the surface of the eye. The change in shape is then imposed by the laser, and you put the flap back down. The advantage of that procedure, the LASIK procedure, is that since the surface of the eye is not disrupted by the laser, vision recovery is much faster.
The other major variation on the theme is the so-called conventional laser treatments, where we're basically programming in the simple glasses correction, sphere and cylinder, or we can do the Custom or the WaveFront treatment, where we're actually imaging the specific contour of the person's eye and a corrective map is generated by the laser to do the correction.
What did Vanessa have?
She had a LASIK procedure where the LASIK flap was created with the femtosecond laser, and then a Custom or a WaveFront treatment was applied.
Now, I know these procedures can be pretty brief. So this laser, firing a laser at the eye, it's a little scary or daunting. But what exactly is happening, and how safe is it?
Well, the laser does fire at a very, very rapid rate because we want to complete the treatments as efficiently as possible. But systems are built in to try to make sure that, in spite of the rapid rate, the treatments are accurate.
We have tracking systems that follow the pupil as the patient is being treated so that if there are any microscopic or very small movements of the eye the laser beam actually is redirected to track the pupil, and that helps to create a predictable and a smooth treatment. In creating the LASIK flap, we also have instruments that help fixate the eye so the patients don't have to worry about moving during treatment.
And they don't feel anything really.
No, they really shouldn't feel anything more than slight pressure on the eye.
How long does one of these procedures take?
Generally, it takes less than a minute to create the LASIK flap and your typical treatment with the EXEMA laser for reshaping the eye is going to be dictated by how high the correction is. The majority of corrections that we do, again the laser treatment component, is less than a minute.
So your time for the patient as an outpatient procedure maybe is, what, 30 minutes, an hour?
We're able to get people in and out of the room in about 20 minutes.
That's incredible. Now, let's back up for a minute. This is not for everybody. It could help many, many people, but how do you evaluate when someone comes for consultation, to make sure that it's right. I know if it's done on the wrong person, there would be complications.
The single most important element in considering refractive surgery is an extremely careful examination to identify specific factors that we know are associated with a higher risk of complications and unpredictable result or a poor accuracy or poor stability of the result. This is really the heart of the refractive surgery evaluation.
There are certainly a number of conditions that would result in unpredictable treatments. There are a number of conditions that could result in correction that isn't stable over time, and most of these conditions are immediately obvious at the beginning of the examination, but there are others that require a very careful scrutiny of the individual patient to identify.
Let's understand some of the things that would be immediately obvious to your team.
Well, certainly there are patients who have corneas that are too thin for consideration for surgery. If you remember that the way the procedure is done is that the laser removes tissue from the cornea, then if you have a cornea that has inadequate thickness to begin with, removing the corneal tissue will result in a cornea that is so thin that it becomes unstable over time.
On the other hand, there are some corneas that have perfectly normal thickness but they tend to have more of an elastic quality than the normal cornea. This may be a little bit more difficult, a little bit more subtle to pick up. If this is not identified and these patients who have these more elastic corneas undergo surgery that removes corneal tissue, they have a very high risk for that cornea becoming unstable over time so that essentially their nearsightedness returns and might actually be more pronounced than before. So identifying the specific patterns that allow us to find these patients is a very, very important part of the examination.
What about a condition that many people have, dry eye? Does that rule someone out?
That's very interesting as well. It turns out that, that we tend to refer to a lot of different conditions as dry eye because ultimately that's how it feels to the patient, which would suggest that you actually have fewer tears produced.
It turns out that there are conditions where you do actually have a reduction in tear production after the LASIK procedure. By and large what we're talking about is the fact that when you create a LASIK approximate flap, you are reducing the nerves that are going to the surface of the eye. This can have multiple effects on the surface of the eye. The most important one, though, is that people who have what we broadly call ocular surface problems before surgery, are definitely at a higher risk of having ocular surface problems after the LASIK. We would want to identify those conditions and characteristics before going into surgery.
One other condition that is unfortunately all too common now, diabetes.
Would someone with diabetes be a candidate or not?
That's a very interesting question. In general we do know very well that diabetes, particularly poorly controlled diabetes, does have an effect on the health of the epithelial or the surface cells of the eye, so we generally consider long-standing and poorly controlled diabetes to be an exclusion criteria for surgery.
However, if someone has well-controlled, late-onset diabetes with a healthy ocular surface, it is reasonable in some cases to consider the procedure. Again, an assessment of the diabetes and the health of the ocular surface is really going to be critical.
Well, fortunately there are people like Vanessa who are candidates when their vision is stable, and I understand you want it stable to know that the change you make is lasting, right?
Exactly. There is a certain number of people in the population whose refractive error, or the power of the eye, is going to drift slowly over time. And of course, if we go ahead and do refractive surgery in that situation, there's nothing to prevent the underlying power of the eye from continuing to drift. So we always want to do the best we can to ensure that the refractive error is stable before going ahead with surgery. That really maximizes the likelihood of a stable long-term visual result.
Tell us a little bit about recovery, what are proper expectations and what are the possible risks.
So in general when people have the LASIK procedure where the LASIK flap is created and the flap is repositioned at the end of surgery, the vision recovers relatively quickly and the most dramatic recovery is going to be recognized over the first night following surgery. Typically, people will wake up the next morning with functional vision. There are many patients who will come in to see us who are actually 20/20 the first day after surgery. However, it does take a while for everything to settle in, so people typically will describe glare and halo at nighttime early after surgery that tends to resolve substantially as the cornea settles in, if not to resolve entirely.
And we also will caution people that because of the fact that we've created this LASIK flap in the cornea, we do need to wait a few weeks before it really heals securely into place. We caution against eye rubbing, early exposure to water, which can expose the patient to water-borne pathogens. We generally tell people no rubbing and try to stay away from swimming for a couple of weeks.
Dr. McLeod, people can turn on the TV or the radio and hear advertisements for some of these surgeries, but you at UCSF, you've actually helped pioneer some of these procedures and done much of the research in many cases that led to FDA approval, so you really have a lot of experience with this.
Yes, we've been engaged in FDA trials for a number of years through the initial approvals of the instruments. Not only did it give us an opportunity to participate in the research process, it also gave us an opportunity to offer, during the development process, the most cutting-edge protocols available. At this point, all of the broad indications for the EXEMA laser have been approved and it's really quite a mature technology now. But that experience certainly has served us well in seeing a lot of patients and a lot of complex scenarios over the years.
Well, I know Vanessa joins me as I'm sure you have many, many patients who thank you for the work you do at the Laser Vision Center at UCSF, and your leadership in ophthalmology. Thank you for explaining this to us.
Dr. Steven McLeod, who is Vanessa's eye surgeon and also chair of ophthalmology at UCSF Medical Center. Vanessa, you're a grateful patient, right?
What would you say to people listening? There are people who maybe are hesitant but yet should have a consultation to see is it right for them. What type of surgery is right for them? Are they in fact a candidate? What would you say to them if they're just sort of on the fence?
Well, I would tell people who are on the fence to definitely see if they are eligible for laser correction surgery. I'm very happy with my new-found corrected vision. It's great and very liberating not to have to worry about contacts and solution, and glasses to be able to see.
There you go. I'm glad you were a candidate and it's worked out so well. All the best, Vanessa Chiu.
I just want to mention that if you want more information about the physicians and services at UCSF Medical Center, just call the physician referral service. That number is (888) 689-UCSF. This is what we do on Patient Power is connect you with leading experts and really inspiring patients like Vanessa who can tell you what it's like from the patient's perspective. I'm Andrew Schorr. Remember, knowledge can be the best medicine of all. Thanks for joining us.
Please remember the opinions expressed on Patient Power are not necessarily the views of UCSF Medical Center, its medical staff or Patient Power. Our discussions are not a substitute for seeking medical advice or care from your own doctor. That’s how you’ll get care what's most appropriate for you.
Recorded February 2011
Reviewed by health care specialists at UCSF Medical Center.
This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.