Standardization of amblyopia screening a goal

Chicago-Mass vision screening for amblyopia in school-age children should be standardized, and Pamela Hutt Berg, CO, COMT, recommended how that might be accomplished Sunday at the American Academy of Ophthalmology annual meeting.

“There is no consensus on what test to use, the appropriate age of the children to be tested, or who should perform screening for amblyopia in children,” Berg said. She noted that while recommendations have been put forth about the optotypes and their spacing that would optimize testing, in clinical practice that standardization does not exist.

“The diversity of testing equipment and methods has made it difficult to validate any one specific approach. In addition, there are differences among the level of training among screeners,” she pointed out. Berg is from the Casey Eye Institute, Portland, OR.

She recommended ways to maximize the screening process. A key contact at schools should be identified in each institution who can coordinate the screening effort by setting up the time and place of the examination and obtaining parental consent forms. Special attention should be paid to the illumination of the space in which the screening will be carried out.

“Most importantly, a follow-up mechanism should be in place so that children who fail screening can be appropriately and promptly referred,” she stated.

The characteristics of a good screening test are that it must be inexpensive, portable, simple for both the screener and the child to learn, and age appropriate for the child. Testing should be carried out by two volunteers in a quiet location, preferably at 10 feet, with no more than two or three children in the room at once. Eyes can be occluded best, she pointed out, with tape cut in 3-inch squares or animal glasses with one side blocked.

“In acuity testing, the tester must go to the critical acuity line as quickly as possible. That line is 20/40 in children under 4 years and 20/30 in children older than 4. Passing is defined as the correct identification of four of five optotypes on the critical line,” she explained.

“If we standardize our methodology better and we train our screeners, we might have a better chance of targeting health care to mandate and fund vision screening in school in all states. Prompt treatment of failed vision screening can improve visual outcomes,” Berg said.