Vision Quest

Advances in surgery are a sight for sore eyes.They say that the eyes are the windows to the soul. If only we could spritz them with something for an instant fix when they get cloudy or blurry, or pop them out and replace them when they stop working properly. OK, we all know it’s not that simple to remedy malfunctioning or diseased eyes, and one pair is all we get. But technological and research advances are making some eye surgery procedures safer and better than ever, and in some cases dramatically saving sight in patients whose worlds would otherwise go dark.For instance, the last couple of years have brought significant progress to cornea transplant surgery. Injury, disease, unlucky genes or other factors can cause a normally clear cornea, which is the front, dome-shaped part of the eye, to cloud up or become opaque, leading to diminished eyesight, says George J. Shaker, M.D., an ophthalmologist at Medical Eye Center in Manchester. In the past, doctors have often remedied this condition by surgically replacing the full thickness of the cornea with a donor’s cornea, Shaker says.But now, in some cases, doctors can use a newer technique to replace just one thin layer of the cornea. DSEK (short for Descemet’s Stripping Endothelial Keratoplasty) is a “huge” advance that involves transplanting donor cells onto the back of the patient’s cornea, says Christopher B. Chapman, M.D., a vitreoretinal specialist at Dartmouth-Hitchcock Medical Center in Lebanon. “It’s like a graft,” he says. Instead of cutting the entire cornea off and putting a new one on, doctors can just put the layer of cells into place. It’s a dramatic change, Chapman says.DSEK offers patients a number of advantages over traditional corneal transplantation, including more rapid recovery. It is less invasive, has more reliable results and requires fewer stitches. (Yes, doctors do put stitches in the eye when needed.) Standard corneal transplantation involves “lots and lots of sutures and is much more involved,” Shaker says.Let there be lasersImprovements have also been made to LASIK, the popular eye surgery that reduces or eliminates the need for corrective lenses. New “wave-front” laser technology allows physicians to customize the LASIK procedure by enabling them to measure optical distortions in the eye and pinpoint individual imperfections. Lasers “continue to get better and better all the time,” Chapman says, resulting in “safer, more predictable outcomes and better vision” for patients – as good as 20/15 in some cases, and even 20/10, “which is almost fighter-pilot vision,” he says.And LASIK is not, as some people assume, strictly for cosmetic purposes or convenience; it can be an alternative for people who are unable to wear contact lenses. “Some people can’t wear contact lenses or their glasses are too thick or there’s some other structural abnormality or reason,” Chapman says. LASIK can provide them with another option.Get back, cataractsCataracts, which cloud the lens inside the eye and are often related to aging, affect more than half of all Americans by age 80, according to the American Academy of Opthalmology, and are one of the most common causes of vision loss. Having cataracts can be like trying to view life through a window that becomes progressively dirtier, until eventually everyday activities become difficult.In the past the standard treatment for cataracts has been to surgically remove the lens of the eye and replace it with an implant that restores only distance vision, leaving nearsighted patients reaching for reading glasses to see close up, Shaker says. But patients today have more options: they can choose to receive implants that treat astigmatism or multi-focal implants, which enable both far and near vision. The new lenses provide a bonus, really – not only can you get your cataracts fixed, you might not need your glasses anymore. Of course, there is a catch; insurance typically does not cover the cost of multi-focal implants or those that can help with astigmatism. Also, not everyone is a good candidate for the specialized lenses.But in general “cataract surgery has really blossomed with the technologies that we have,” Shaker says. State-of-the-art cataract surgery usually involves entering the eye through a tiny incision, he says. Doctors use an ultrasonic device to break up the lens and vacuum it out, and then the implant, which is folded up into an extremely small cartridge, is inserted. Once inside the eye, the implant opens up and is re-positioned by the doctor. Cataract surgery “used to be a big incision with lots of stitches,” Shaker says. “Now it’s done with no stitches and typically takes about 10 minutes. It has really come a long way.”Here’s a needle in your eyeThe thought of a needle piercing your eye probably won’t make you quiver with anticipation – then again, maybe it will – but groundbreaking “intravitreal” injections are being used today for a variety of eye ailments, including diabetic retinopathy, a leading cause of blindness in the United States. Diabetic retinopathy occurs when the effects of diabetes damage the retina, which is located in the back of the eye. Doctors inject steroids or non-steroidal “anti-VEGF agents,” which are antibody-like drugs, into the eye. The injections “have literally changed the landscape of blindness in America,” Chapman says. “They have revolutionized what we do. Three or four years ago, some diabetic patients used to uniformly go blind no matter what we did for them. Now we’re able to preserve vision in the vast majority of patients. It’s breathtaking.” And the injections, believe it or not, are painless; the doctor numbs the eye before getting too close with the needle.Injection therapy also can be vision-saving in people with vein “occlusions” or blockages, as well as patients who experience age-related macular degeneration (AMD), a disease that gradually destroys central vision, says Nancy E. Bonachea, M.D., a retina specialist at Retina Vision Center in Bedford. Anti-VEGF injections stabilize vision in 90 percent of AMD patients and improve vision in about a third of AMD patients, she says. Patients typically require a series of injections, given right in the doctor’s office. Other treatments involving injections are being researched, including new surgical and radiation approaches that may be used in combination with injections in the future, Bonachea says. NHAnother eye on the futureOne of the most promising areas in surgical eye care for the retina harnesses the power of stem cells, says Christopher B. Chapman, M.D., a vitreoretinal specialist at Dartmouth-Hitchcock Medical Center in Lebanon. Researchers have discovered how to turn adult stem cells into specialized cells that nourish the retina. This is especially good news for patients with retina woes such as macular degeneration, a common condition that can lead to severe vision loss. Researchers have successfully transplanted stem cells into mice that have genetic abnormalities of the retina and have triggered some return to visual functioning, albeit temporarily, Chapman says. “This is really taking off in the field,” he says. “They’re not ready for humans yet, but that day will come,” possibly within 10 to 15 years.Calling all cyborgsAn eye surgery breakthrough for genetic blindness appears to be on the horizon – although it will only be suitable for “a handful of patients,” says Christopher B. Chapman, M.D., a vitreoretinal specialist at Dartmouth-Hitchcock Medical Center in Lebanon. Researchers, including some in New Hampshire at Dartmouth, are exploring the idea of surgically implanting a computer chip in the eye. The artificial chip has been working in selected patients in Europe. Sounds Star Trekian, you say? The results so far certainly are exciting: some patients with the implanted chip “were able to see some figures and read a little bit,” Chapman says, and these were patients who were “almost completely blind” prior to insertion of the chip.

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