The eyes have it: Lasik and beyond
KUSA - Talk eye surgery and most people automatically assume the subject is laser vision correction, Lasik.
However, maybe you'd be better off with a type of contact lens that's implanted within the eye, right in front of your own lazy lens.
While Lasik has grabbed the most public attention over the past few years, surgeons have developed several other innovations that may offer some patients even better vision correction than Lasik.
In fact, many eye surgeons say, it's hard to get patients to focus on treatments other than Lasik, perhaps because the latest refinements in the technology are so fascinating.
Conventional Lasik featured using a surgical blade, a microkeratome, to cut a flap in the outermost surface of the eye to allow exposure of the cornea. Surgeons then used a laser to vaporize a corrective prescription into the clear tissue in front of our own lens.
The laser essentially changed the shape of the front of the eye to restore crisp focus on the retina, the visual screen on the back of our eyes.
Wavefront technology provided Custom Lasik, where the surgeon and the laser use a three-dimensional map that takes into account the optical imperfections of each eye, and not just the prescription needed for vision correction.
For many patients, Custom Lasik reduces after-effects like night vision glare, and halos around bright light.
However, the newest technology now allows for ‘bladeless Lasik.’ It's called Intralase and it uses laser-burst bubbles seated just beneath the cornea to make a thinner flap than earlier generations of Lasik.
The first laser sends a wave of energy across the cornea that creates overlapping bubbles of space. The laser bevels the layers of bubbles along the outer perimeter, stacking them on each other enough that it cuts a thin corneal layer the surgeon can simply lift up with a small metal spatula.
The eye surgeon then uses a second laser to etch the prescription in the cornea to correct the patient's vision.
However, just because it's the latest, surgeons say Intralase may not necessarily be the greatest for every patient. It makes use of two lasers instead of one, and that means it's more expensive for the doctors, and therefore more expensive for patients.
It is ideal though for patients who have thin corneas, and wouldn't otherwise be candidates for conventional Lasik.
Let's take a look from the front of the eye to the back of the eye, and talk about other ways to correct vision.
Implantable contact lenses: How about a contact lens you never have to enzyme or re-hydrate? It's called a Phakic (pronounced fay-kick) intraocular (within the eye) lens, or IOL for short.
Patients between the ages of 21 and 50 benefit most from this internal contact lens, especially those with moderate to severe nearsightedness. (That means they can see close up, but their mid-range and distance vision is lacking.)
This is an outpatient procedure, where the corrective lens is folded into a tiny insert device, and is deployed through a 3mm incision in front of the patient's lens. The Phakic lens gives very predictable results and restores a full range of vision.
One major plus is the Phakic lens can be removed easily and replaced with another lens, and it leaves the door open for more advanced technology further down the line.
The lens itself is made of a collagen polymer that the body does not reject as a foreign body. An ultraviolet filter is even built within the lens, and that can protect our own lens from developing cataracts later on.
One version of this type of lens is implanted in front of our own lens, another is inserted directly behind the lens.
Lens replacement: Three artificial lenses are on the market now that can replace our own defective or lazy lens. Over time, our lens stiffens and isn't as pliable as it needs to be to bring images into focus on the retina.
During lens replacement, surgeons use energy waves, similar to those that break up kidney stones, to break up our own lens so it can be suctioned out in small, harmless pieces.
Then, one of three kinds of synthetic lenses are inserted into the eye.
The ReStor multifocul lens has been in use the longest in cataract patients, and now it's among two others, Crystalens and ReZoom that even patients without cataracts are using.
Why? Because these lenses restore a full range of vision in most patients, including that nose-to-arm-length vision that most people in their 40's and 50's lose. (You've seen them at the restaurants, having the waiter go long with the menu so they can read it.)
The cost of these lens replacements is slightly more than Lasik, but the range of vision is better than Lasik can provide in most instances. Those with cataracts often get at least partial coverage from their health or vision insurance for these types of lenses.
Synchrony, NuLens and TetraFlex are other names of these implantable lenses. These cannot be removed, once in place, but Lasik or other treatments would still be possible if optimal visual correction wasn't achieved with the lens alone.
Just as with Lasik, patients with large pupils need to discuss this carefully with their eye doctor.
What's next? Surgeons are working on even more ways to use lasers to do multiple kinds of vision corrections on the same eye. And the optics of internal lenses are bound to get better and better, helping millions of Americans keep their lives in clear focus.
