Vision Exams Can Be Costly
Vaccination Against Optic Nerve Damage in Trials
High-Tech Vision Screeners Beat the Old Standard
Eye-Catching Jewelry
Vision Exams Can Be Costly
There was good news and bad news recently when an ophthalmologist involved in Tennessee’s statewide photoscreening of preschool children studied the program’s clinical results.
The vast majority of the children identified as needing further examination, and whose exams proved normal, were sent home without eyeglass prescriptions. But nearly 20 percent were prescribed spectacles.
For this group of children, the study challenges the necessity of the prescriptions, and the author voices related financial concerns.
At those rates, a single mandatory eye exam before kindergarten would cost American parents more than $200 million annually just to pay for the unneeded eyeglasses, the study by Sean P. Donahue, MD, PhD, concludes. And that’s in addition to the familial stress of a parent trying to force a preschooler to wear glasses.
“Parents have only a certain amount of emotional change they can spend, and most parents are well-meaning. So they’ll want their child to wear the glasses the doctor prescribes,” Dr. Donahue said. “They’ll be spending a tremendous amount of emotional change doing this, even though it’s not necessary.”
For the study, Dr. Donahue looked at the results of photoscreening of 102,508 Tennessee children in a voluntary statewide program conducted by ophthalmologists and optometrists. Of the group, 890 children were referred for further evaluation and found to have normal vision. However, 174 (19.5 percent) of these children were prescribed spectacles anyway. The prescribing rates varied depending on who conducted the exam: 1.8 percent for pediatric ophthalmologists, 11.7 percent for comprehensive ophthalmologists and 35.1 percent for optometrists.
A few of those prescriptions probably were appropriate based on the children having other visual symptoms not described by the program’s data, Dr. Donahue noted. But the remaining, prescriptions show the need for educating eye professionals about the special visual needs of young children, he said.
“Many people tend to think of children as little adults,” Dr. Donahue said. “But a child will do just fine with mild uncorrected myopia or astigmatism, and can easily accommodate through 3 or more diopters of hypermetropia.”
Dr. Donahue presented his study this spring at the meeting of the American Association for Pediatric Ophthalmology and Strabismus; it will appear in the June issue of the Journal of AAPOS.1
Most studies of preschool vision screening have judged success only on how many children are identified as needing comprehensive eye examination, he said. “What we haven’t looked at is what happens when the child gets to the doctor,” he said. “Is the follow-up care the kids get reasonable, cost-effective and evidence-based?”
Addressing that aspect of preschool screening is important because of pressure in states to enact mandatory professional eye exams, said Dr. Donahue.
His take-home message to clinicians: “Remember to perform cycloplegic refraction on all children who present for an eye examination, and remember that a child’s visual demands are not the same as an adult. Ask about symptoms, and take into account the tested acuity of the child. Finally, familiarize yourself with the prescribing guidelines in the Academy Preferred Practice Pattern for pediatric eye examination.”2
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1 To view the article, go to www.jaapos.com.
2 Available at www.aao.org.
Glaucoma Update
Vaccination Against Optic Nerve Damage in Trials
The main pharmacologic approaches to glaucoma generally go down one of two philosophical roads: either reducing the IOP that leads to optic nerve damage, or the still-preclinical road of blocking certain ischemic by-products that trigger cell death.
But one clinical study that began this spring will investigate a third route—in effect, “vaccinating” the optic nerve against damage.
The trial will test a multiple sclerosis drug (Copaxone), to see if its induction of a mild autoimmune response will protect glaucoma patients’ optic nerves. Teva Pharmaceutical, maker of the drug, and Proneuron Biotechnologies will be conducting the trial, said Michal Schwartz, PhD, an Israeli scientist whose group has been researching the idea over the last decade.
The underlying premise of this approach is that an autoimmune response is the body’s natural defense against the by-products of cellular injury, and represents a method for clearing out toxic amounts of molecular debris such as glutamate, Dr. Schwartz’s group writes.1
“An autoimmune disease might be the result of a failure to control properly the injury-induced autoimmune response, the purpose of which is essentially beneficial,” the authors write.
The goal of this type of approach to glaucoma would be to boost the autoimmune response to the initial insult from high IOP, and thus prevent secondary cell loss. But that would have to be done without causing an autoimmune overreaction.
In rats, the group found that retinal ganglion cells were protected from IOP-induced damage if vaccinated with a peptide derived from an immunodominant antigen in the eye, interphotoreceptor-retinoid binding protein. Myelin-derived antigens, which aren’t unique to the eye, were not protective. But Cop-1, the synthetic copolymer that will be used in the clinical trial, appeared to bridge the site-specificity problem by cross-reacting weakly with a wide variety of cells, including the retinal ganglion cells, the researchers report.
Dr. Schwartz, professor of neuroimmunology at the Weizmann Institute of Science, expressed optimism about what this approach, and Cop-1, might mean eventually for treatment of glaucoma.
And she acknowledged it’s been difficult to get the idea across to the ophthalmic community, because of the long-held idea that any immune response in the eye equals inflammation.
“Vaccination for glaucoma is based on two novel concepts for clinicians—neuroprotection for glaucoma and that T cells are beneficial. A few years ago it was received by a high skepticism,” said Dr. Schwartz. “Now the community is more open definitely to the idea of neuroprotection. There is still a gap in differentiating between immune response and inflammation.”
In a review article published last year2 she writes: “It should be emphasized that therapeutic vaccination will not prevent the onset of glaucoma, but it may provide a way to prevent or at least slow down its propagation. Once [the] regimen and formulation are optimized for protection of retinal ganglion cells against death induced by an increase in IOP, Cop-1 can immediately be developed as a therapy for glaucoma.”
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1 Bakalash, S. et al. Invest Ophthalmol Vis Sci 2003;44(8): 3374–3381.
2 Invest Ophthalmol Vis Sci 2003; 44(4):1407–1411.
Device Update
High-Tech Vision Screeners Beat the Old Standard
Is it possible for high technology to help screen children better for sight-threatening visual problems? Yes it can, the federally funded Vision in Preschoolers study concluded recently.
Reporting in the April Ophthalmology, the VIP Study Group identified four alternatives that do a better job than traditional stereoacuity tests at detecting amblyopia, strabismus, significant refractive error and unexplained reduced visual acuity. The four include: noncycloplegic retinoscopy, the Retinomax Autorefractor, SureSight Vision Screener and Lea Symbols.1
Initial results from the Vision in Preschoolers study show why states need to be careful about eye exam mandates, said Academy spokesman and former Academy president Michael R. Redmond, MD. “This illustrates the folly of mandating one technique of identifying children with eye problems over all others,” he said.
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1 Schmidt, P. et al. Ophthalmology 2004;111(4):637–650.
Cosmetic Surgery
Eye-Catching Jewelry
In the age of the Internet, it was perhaps inevitable that surgeon Gerrit R. J. Melles, MD, PhD, would experience his 15 minutes of fame after presenting the idea of “eye jewelry” to a stodgy conference of Dutch ophthalmologists.
A reporter wrote a story about the JewelEye decorative conjuctival implant for Reuters, and the news raced around the world.
Dr. Melles, who usually presents surgical papers that few outside of ophthalmology would note, was nonplussed by all the attention. He explained that the cosmetic extraocular implant was merely a spinoff from a glaucoma drainage device he had been researching.
“Purely from an ophthalmic point of view, the procedure is very simple, and it is performed ‘outside’ the eye,” Dr. Melles said. “If the procedure is performed by an experienced ophthalmologist under sterile conditions, the risk of infection may be negligible.”
In answer to negative reactions from physicians about the procedure, he responded that these comments arise out of emotion, not out of reason.
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News compiled by Linda Roach.
