воскресенье, 23 сентября 2012 г.

At first sight: early screening can save more than your child's vision.(health report) - Sarasota Magazine

according to researchers at Miami's Florida International University, one in every 677 children in America is afflicted with some sort of treatable eye disease, including conditions that can cause blindness.

Strabismus, or 'crossed eyes,' and amblyopia, or 'lazy eye,' both affect as many as 5 percent of all preschool children. Infantile glaucoma occurs in one out of every 10,000 births, and cataracts account for 16 percent of all cases of legal blindness in children under the age of five. Yet only 14 percent of those below the age of six are likely to have had an eye examination, according to the American Optometric Association (AOA). And even though one in four school-age children has a vision-related problem, Kentucky is still the only state that requires professional eye exams for all pre-kindergarten students.

'An infant's eyes grow continuously after about seven weeks in the womb,' says Dr. Charles Doering, a vitreoretinal surgeon at Sarasota's Center for Sight. And a lot can go wrong in those critical days before birth.

One of the most ominous developments is retinoblastoma, a cancer caused by fetal retinal cells, called retinoblasts, that grow out of control, forming a tumor that fills much of the eye. About 40 percent of the time, this abnormality is genetic. Scientists have traced it to a mutation in a tumor suppressor gene known as Rb or RB1. About 90 percent of the children who inherit an abnormal Rb gene from a parent develop retinoblastoma in one or both eyes.

'The important thing about retinoblastoma is that children who develop it are at risk for developing secondary cancers of the bone and skin,' says Doering. If cells break away from the original tumor to other parts of the eye, they can create pressure inside the eye that leads to glaucoma. They can also spread to the optic nerve and brain, the lymph nodes, then to internal organs and the bones.

[ILLUSTRATION OMITTED]

Retinoblastoma is easy to spot by looking into a child's dilated eyes with a bright penlight or an ophthalmoscope. While a normal retina reflects back red, a retinoblastoma tumor will create a white reflection, a condition called leukocoria. The first clue for many parents is a child's photograph where the flash produces one red eye and one white eye.

Unfortunately, by the time a tumor reaches this stage, it may be too late to save the eye. Between 86 to 90 percent of children who are diagnosed with retinoblastoma because of leukocoria survive, but a Cornell University study of nearly 2,000 retinoblastoma patients who had been treated at the hospital found that saving a child's vision requires early detection. Patients with a family history of retinoblastoma who were screened from birth with dilation examinations had a much better chance of retaining their eyesight than nonscreened patients with similar histories.

But in 60 percent of cases, retinoblastoma develops for no known reason. Joey Bergsma of Lake Worth, Fla., was three years old when he died of the disease. 'We're never going to know just how long he had it,' says Bergsma's grandmother, Pam. Although photographs taken of the boy showed obvious signs of leukocoria, his family was unfamiliar with the symptoms. With no history of the disease to alert his doctor, Joey was not diagnosed until after the cancer had spread.

Now Pam Bergsma is pushing for legislation to require an eye dilation exam for all newborns, at all six- to eight-week well-baby exams, and at all six- to nine-month well-baby exams. She knows that the American Academy of Pediatrics (AAP) recommends 'red reflex' screening with an ophthalmoscope for all infants within their first two months, but only in a darkened room to maximize pupil dilation. It recommends medical dilation if anything looks askew.

The policy infuriates Bergsma. 'You only have a 30-percent chance of detection in an undilated eye,' she claims. The Retinoblastoma Center at the University of Southern California agrees. According to researchers there, an infant's pupil is so small that the detection of any intraocular condition is rare without pupil dilation.

But many doctors are hesitant to dilate an infant's eyes. 'Personally, I don't do it,' says Sarasota pediatrician Dr. Ted Meyers. If he spots anything unusual in a young patient, he refers them to a pediatric ophthalmologist.

'You can get some fairly significant medical complications [from dilation],' adds Meyers, who has practiced for 21 years. In 2003, the Florida Society of Ophthalmology (FSO) issued a statement citing hypertension, slow heart rates and behavioral disturbances as potential reactions from dilating agents. It claims that these side effects occur at a higher rate than retinoblastoma tumors, so dilation is not justified.

But opinions vary on just how many cases are seen in this country every year. The American Cancer Society says about 250 children are diagnosed with retinoblastoma annually, while the National Institutes of Health puts the number at 400. Other estimates range from 500 a year to one in 10,000. Doering saw more than 300 cases of retinoblastoma in the three years he spent at Cornell before moving to Sarasota last year.

Like all the doctors interviewed for this story, Doering hasn't treated a single case of retinoblastoma here. 'It's something that's more common in demographics with more children,' says Dr. Ronni Chen, a pediatric ophthalmologist at Kantor Eye Institute in Sarasota.

Bergsma counters that all childhood cancers are rare, compared to adult cancer, and that dilating an infant's eyes could ensure the detection of other retinal diseases that can be treated if detected early enough. Retinoblastoma tumors, for example, can be blasted away with a laser if caught in time.

Dr. Ronald Berkman, dean of Florida International University, claims the cost to Florida in direct and indirect costs for a blind child over the course of a lifetime can reach $2 million. 'The cost of the proposed screening is that for two drops of dilating solution and 10 seconds of a nurse's time,' he wrote in a letter to the Florida State Legislature urging passage of a newborn eye-screening bill.

Despite the American Academy of Pediatrics' policy on even minimal red reflex testing, fewer than 22 percent of all preschool children receive any type of vision screening at all. In 80 percent of the patients in the Cornell study, the disease was initially detected by the child's family or friends. Only 8 percent of the cases were discovered by pediatricians and only 10 percent by ophthalmologists.

The AOA reports that in a study of 102 private pediatric practices, doctors had screened just 38 percent of their three-year-old patients. A mere 26 percent of children who failed the American Academy of Pediatrics screening guidelines were subsequently referred for professional eye exams.

That's not good enough for Bergsma, who recounts stories of mothers who have been rebuffed by their pediatricians when they requested a formal exam, including one mother from Miami she met just last April. 'Why, four years after my grandson died, was I at the funeral of a little boy who died of the same thing?' she asks. 'This is just insane.'

RELATED ARTICLE: A REAL EYE-OPENER

If the thought of having the surface of your eye peeled back like a grape has kept you from enjoying the benefits of LASIK, think about IntraLase.

IntraLase replaces the handheld metal blade currently used in LASIK with the safety and precision of an ultra-fast laser, virtually eliminating blade-related complications, according to Dr. William J. Lahners, a board-certified ophthalmologist and LASIK surgeon and director of Vision Services at Sarasota's Center for Sight.

Traditional LASIK uses an oscillating metal razor, called a microkeratome, to create the corneal flap that is the first step in performing the procedure. InterLase fires a small pulse of light at 15,000 times per second, producing a series of miniscule bubbles that actually lift the cornea's surface. 'We don't actually cut or destroy anything,' says Lahners.

The result, according to one study of 375 eyes, is unprecedented accuracy and a significant reduction in injury to the eye. 'We end up with a flap that is exactly what we wanted,' adds Lahners. This is important, since most LASIK-related complications arise from cuts made to the cornea.

[ILLUSTRATION OMITTED]

IntraLase also seems to prevent a complication called surgically induced astigmatism. 'One of the limiting factors [of LASIK] was due to some of the distortions caused by the microkeratome flap,' Lahners explains. Because the cuts are irregular, 'They almost always add some degree of distortion.' IntraLase produces a flap that is even all the way around.

Currently, Center for Sight is one of only 10 vision centers in Florida offering the special laser, which has been FDA-approved for three years. Lahners says its expense adds about 10 percent to the cost of LASIK at Center for Sight, but says, 'Right now, one out of every eight LASIK procedures done in this country is being done with an IntraLase laser. It is very exciting technology.'

RELATED ARTICLE: WHEN TO SCREEN

After an initial screening at birth, the American Optometric Association recommends the following eye screening schedule.

[ILLUSTRATION OMITTED]

 Patient Age          Examination Interval  Birth to 24 months   At six months Two to five years    At three years Six to 18 years      Before the first grade and every two years after