Long-term visual outcomes in extremely low-birth-weight children (an American Ophthalmological Society thesis)

Abstract

Purpose: The goal is to analyze the long-term visual outcome of extremely low-birth-weight children.

Methods: This is a retrospective analysis of eyes of extremely low-birth-weight children on whom vision testing was performed. Visual outcomes were studied by analyzing acuity outcomes at >/=36 months of adjusted age, correlating early acuity testing with final visual outcome and evaluating adverse risk factors for vision.

Results: Data from 278 eyes are included. Mean birth weight was 731g, and mean gestational age at birth was 26 weeks. 248 eyes had grating acuity outcomes measured at 73 +/- 36 months, and 183 eyes had recognition acuity testing at 76 +/- 39 months. 54% had below normal grating acuities, and 66% had below normal recognition acuities. 27% of grating outcomes and 17% of recognition outcomes were </=20/200. Abnormal early grating acuity testing was predictive of abnormal grating (P < .0001) and recognition (P = .0001) acuity testing at >/=3 years of age. A slower-than-normal rate of early visual development was predictive of abnormal grating acuity (P < .0001) and abnormal recognition acuity (P < .0001) at >/=3 years of age. Eyes diagnosed with maximal retinopathy of prematurity in zone I had lower acuity outcomes (P = .0002) than did those with maximal retinopathy of prematurity in zone II/III. Eyes of children born at </=28 weeks gestational age had 4.1 times greater risk for abnormal recognition acuity than did those of children born at >28 weeks gestational age. Eyes of children with poorer general health after premature birth had a 5.3 times greater risk of abnormal recognition acuity.

Conclusions: Long-term visual development in extremely low-birth-weight infants is problematic and associated with a high risk of subnormal acuity. Early acuity testing is useful in identifying children at greatest risk for long-term visual abnormalities. Gestational age at birth of </= 28 weeks was associated with a higher risk of an abnormal long-term outcome.

Figures

FIGURE 1

Six Teller acuity cards showing varying grating widths from fine (on left) to coarse (on right). Note “peephole” in center of each card for observation of eye movement.

FIGURE 2

Monocular forced-choice preferential looking grating acuity testing. Toddler (held by mother) points at gratings on Teller cards, which are presented by tester/observer.

FIGURE 3

Crowded Letter “O”: Letter “O” with crowding bars around it, as used for HOTV recognition acuity testing.

FIGURE 4

Early grating acuity differences from mean normal: Chart shows grating acuity difference from mean normal for adjusted age in 100 eyes of infants tested at 6 months or less adjusted age. Visual acuity difference is expressed as logMAR.

FIGURE 5

Early grating acuity differences from lower limit of normal: Chart shows grating acuity difference from the lower limit of the normal range for adjusted age in 100 eyes of infants tested at 6 months or less of adjusted age. Visual acuity difference is expressed as logMAR.

FIGURE 6

Late grating acuity outcomes: Chart shows distribution of grating acuity vision in 248 eyes tested at 36 months or more of adjusted age. Visual acuity is expressed as logMAR.

FIGURE 7

Late grating acuity differences from mean normal: Chart shows grating acuity difference from mean normal for adjusted age of 248 eyes of children tested at 36 months or more of adjusted age. Visual acuity difference expressed as logMAR.

FIGURE 8

Late grating acuity differences from lower limit of normal: Chart shows grating acuity difference from the lower limit of the normal range for adjusted age in 248 eyes of children tested at 36 months or more of adjusted age. Visual acuity difference expressed as logMAR.

FIGURE 9

Recognition acuity outcomes: Chart shows distribution of recognition acuity vision in 183 eyes tested at 36 months or more of adjusted age. Visual acuity difference expressed as logMAR. LP = light perception; NLP = no light perception.

FIGURE 10

Recognition acuity differences from mean normal: Chart shows recognition acuity difference from mean normal for adjusted age in 183 eyes of children tested at 36 months or more adjusted age. Visual acuity difference expressed as logMAR.

FIGURE 11

Recognition acuity differences from lower limit of normal: Chart shows recognition acuity difference from the lower limit of normal for adjusted age in 183 eyes of children tested at 36 months or more of adjusted age. Visual acuity difference expressed as logMAR.

FIGURE 12

Visual outcomes for Zone I eyes compared with the mean of normal for age: Grating acuity difference from mean normal for adjusted age in 59 eyes with maximal ROP occurring in zone I. Visual acuity difference expressed as logMAR.

FIGURE 13

Visual outcomes for Zone I eyes compared with the lower limit of normal for age: Grating acuity difference from lower limit of normal range for adjusted age in 59 eyes with maximal ROP occurring in zone I. Visual acuity difference expressed as logMAR.

FIGURE 14

Visual outcomes for Zone II/III eyes compared with the mean of normal for age: Grating acuity difference from mean normal for adjusted age in 119 eyes with maximal retinopathy of prematurity occurring in zone II/III. Visual acuity difference expressed as logMAR.

FIGURE 15

Visual outcomes for Zone II/III eyes Compared with the lower limit of normal for age: Grating acuity difference from lower limit of normal range for adjusted age in 119 eyes with maximal ROP occurring in zone II/III. Visual acuity difference expressed as logMAR.

FIGURE 16

Normal grating acuity development based on data from normal full-term infants. (Courtesy of Eileen E. Birch, PhD, Dallas, Texas)