Eliminating this preventable cause of vision loss, one screening at a time.

Amblyopia is a preventable cause of permanent vision loss, with a prevalence of approximately 3% in untreated children and adults.¹ If diagnosed and managed by age 3, however, the prevalence of clinically significant amblyopia decreases to 1%. The U.S. Preventative Services Task Force recommends amblyopia vision screenings for children ages 3 to 5 years old.²

The catch, according to Omondi Nyong’o, MD, a pediatric ophthalmologist at Sutter Health in Palo Alto, Calif., is that “the screening test must be accessible, easy to use and translate research into real patient care” — a rather tall order for a test involving such young children.

The American Association for Pediatric Ophthalmology and Strabismus recommends instrument-based photoscreening in infants and young children.³ Their policy statement notes that photoscreening is rapid, requiring minimal cooperation of the child, and is particularly beneficial in the preverbal or developmentally delayed child.

Visual acuity testing becomes reliable in most children over the age of 4. “Visual acuity and subjective refraction testing after age 4 provide valuable information about the child’s verbal skills, comprehension and neuro-ophthalmic pathway,” Dr. Nyong’o says.

A CHILD-FRIENDLY SOLUTION …

To meet the challenge, Plusoptix Inc. offers the S16, a stationary photoscreener with a child-pleasing cat face, and the S12C and S12R mobile photoscreeners with happy faces. The devices use binocular infrared photo retinoscopy with 54 LED illumination to measure a range of prescriptions from -7.00 D to +5.00 D in 0.25-D increments, through undilated pupils. The S16 uses a medical power adapter while the S12 uses six rechargeable AA batteries.⁴ Other differences in the models include their documentation and data storage options.

The Plusoptix vision screener is designed to be used by family physician and pediatric practices to detect vision disorders, including anisometropia, anisocoria and strabismus, by measuring the child’s refraction, pupil diameter and symmetry of the corneal reflexes. Based on age-specific normative thresholds, the device displays a result of pass or refer.

… THAT DELIVERS CLINICALLY

In 2014, Kirk et al found a sensitivity of 91%, a specificity of 71% and inconclusive rate of 10% for 62 children, with a mean age of 5.2 years, with the S12.⁵

A study of 3-year-old children conducted in 2015, by Lowry, Wang and Nyongo’o, investigated the referral rate, reliability and positive predictive value of the Plusoptix vision screener.⁶ Of 766 children screened, 74 (9.6%) were referred to a pediatric ophthalmologist. Only 35 (47%) received a comprehensive eye-examination, including cycloplegic retinoscopy, and of these, 18 had amblyopia, one with strabismus, giving a positive predictive value of 51%.

Also, the investigators showed that the inclusion of Plusoptix in a community-based multispecialty group practice significantly increased the rate of vision screenings at 3-year-old well-child checkups from 10% to 80%.

AT WORK IN THE PRACTICE

One key to success with any screening program is to have a low enough threshold to prevent false negatives and avoid liability, but a high enough predictive value that there is reliability in the results.

“It is important to avoid causing unnecessary anxiety in parents whose child has just failed a screening test. Screening of children younger than 3 creates a lot of noise and inconclusive results,” Dr. Nyong’o says. “By limiting testing to 3-year-old children, Plusoptix offers a more impactful application.”

According to Dr. Nyong’o. Sutter Health originally added a unit in one of its multidisciplinary practices. Now, Plusoptix has been implemented on all 33 Sutter Health campuses, with mapped screening protocols for all 3-year-old children, to improve quality of care.

The manufacturer reports that the Plusoptix vision screen’s pass or refer threshold criteria can be adjusted as necessary, based on statistics from examining real patients.

“Implementing the Plusoptix vision screener into practice is an excellent, innovative management strategy for business growth,” says Dr. Nyong’o. More importantly, it may help eliminate amblyopia, one small child at a time. OM

REFERENCES

1. Webber AL, Wood J. Amblyopia: prevalence, natural history, functional effects and treatment. Clin Exp Optom. 2005;88:365-375.
2. Force USPST. The Guide to Clinical Preventive Services 2014. http://www.ahrq.gov/professionals/clinicians-providers/guidelines-recommendations/guide/cpsguide.pdf . Accessed July 2, 2018.
3. Miller JM, Lessin HR. Instrument-based pediatric vision screening policy statement. Pediatrics. 2012;130:983-986.
4. Plusoptix device comparison. https://plusoptix.com/images/vision-screening/downloads/comparison-visionscreener-en.pdf . Accessed July 2, 2018.
5. Kirk S, Armitage MD, Dunn S, Arnold RW. Calibration and validation of the 2WIN photoscreener compared to the PlusoptiX S12 and the SPOT. J Pediatr Ophthalmol Strabismus. 2014;51:289-292.
6. Lowry EA, Wang W, Nyong’o O. Objective vision screening in 3-year-old children at a multispecialty practice. J AAPOS. 2015;19:16-20.