In the clinic, a detailed parental interview was conducted, including questions regarding family income and preschool or daycare enrollment.11 (link) The examination, described in detail elsewhere,11 (link),12 (link) included VA testing, evaluation of ocular alignment, cycloplegic refractive error measurement, and anterior segment and dilated fundus evaluations. Cycloplegic refraction was performed with the Retinomax Autorefractor (Right Manufacturing, Virginia Beach, VA) at least 30 minutes after instilling the second of 2 drops of 1% cyclopentolate given 5 minutes apart. Cycloplegic retinoscopy was performed if Retinomax readings with confidence ratings of ≥8 were not obtained in both eyes after 3 attempts per eye. If parents refused cycloplegic eyedrops, non-cycloplegic retinoscopy was performed.
Presenting monocular distance VA measurement was attempted using an electronic visual acuity (EVA) tester6 (link) with the ATS protocol.5 (link) The EVA system uses a handheld device programmed with the protocol algorithm to control the presentation of high-contrast black-and-white single HOTV optotypes framed by crowding bars spaced a half-letter width from the letter on a 17-inch monitor. The ATS testing algorithm has been described previously;5 (link),6 (link) an initial screening phase obtaining an approximate VA threshold is followed by a first threshold determination phase, a reinforcement phase, and a second threshold determination phase. The VA score, measured in 0.1 logMAR increments from 20/800 to 20/16, is the smallest logMAR level passed in either of the two threshold phases.
The VA testing protocol specific to MEPEDS has been reported in detail.3 (link) Children were seated 3 meters from the monitor with a lap card containing the single-surround HOTV letters. Children who had difficulty comprehending the task underwent a binocular pretest at near, which if passed was followed by a binocular pretest at 3 meters, and monocular threshold testing for those able to complete the pretests. Children were instructed to identify the letter on the monitor verbally or by pointing to the matching optotype on the hand-held card; those who knew their letters were still encouraged to refer to the card. The right eye was tested first, followed by the left, with the fellow eye occluded with an adhesive patch or, rarely, occluding glasses. Testing was attempted on all children, including those with developmental delay or disability.
Presenting monocular distance VA measurement was attempted using an electronic visual acuity (EVA) tester6 (link) with the ATS protocol.5 (link) The EVA system uses a handheld device programmed with the protocol algorithm to control the presentation of high-contrast black-and-white single HOTV optotypes framed by crowding bars spaced a half-letter width from the letter on a 17-inch monitor. The ATS testing algorithm has been described previously;5 (link),6 (link) an initial screening phase obtaining an approximate VA threshold is followed by a first threshold determination phase, a reinforcement phase, and a second threshold determination phase. The VA score, measured in 0.1 logMAR increments from 20/800 to 20/16, is the smallest logMAR level passed in either of the two threshold phases.
The VA testing protocol specific to MEPEDS has been reported in detail.3 (link) Children were seated 3 meters from the monitor with a lap card containing the single-surround HOTV letters. Children who had difficulty comprehending the task underwent a binocular pretest at near, which if passed was followed by a binocular pretest at 3 meters, and monocular threshold testing for those able to complete the pretests. Children were instructed to identify the letter on the monitor verbally or by pointing to the matching optotype on the hand-held card; those who knew their letters were still encouraged to refer to the card. The right eye was tested first, followed by the left, with the fellow eye occluded with an adhesive patch or, rarely, occluding glasses. Testing was attempted on all children, including those with developmental delay or disability.
