Prevalence and course of strabismus in the first year of life for infants with prethreshold retinopathy of prematurity: findings from the Early Treatment for Retinopathy of Prematurity study.

OBJECTIVE To present strabismus data for premature infants with prethreshold retinopathy of prematurity (ROP) enrolled in the Early Treatment for Retinopathy of Prematurity study. DESIGN The prevalence of strabismus was tabulated for all of the infants with high-risk prethreshold disease who participated in the randomized trial of the Early Treatment for Retinopathy of Prematurity study and were examined at 6 and/or 9 months' corrected age as well as for all of the infants with low-risk prethreshold disease who were examined at 6 months' corrected age. MAIN OUTCOME MEASURES Presence or absence of strabismus at 6 and 9 months' corrected age. RESULTS The prevalence of strabismus at 6 months was higher for infants with high-risk prethreshold ROP than for those with low-risk prethreshold ROP (20.3% vs 9.6%, respectively; P<.001). Risk factors associated with the development of strabismus at 9 months include abnormal fixation behavior, presence of amblyopia, and outborn birth status (ie, born outside of a study-affiliated hospital). At 9 months, 30% of infants with high-risk prethreshold ROP had strabismus, although only 42% showed strabismus at 6 months. Thirty percent of infants with strabismus at 6 months showed normal alignment at 9 months. CONCLUSIONS Infants with high-risk prethreshold ROP show significant variability in the presence vs absence of strabismus in the first year of life; thus, conservative management is recommended. APPLICATION TO CLINICAL PRACTICE Ophthalmologists managing strabismus in infants who have high-risk prethreshold ROP should be aware of the significant variability in ocular alignment during the first year of life.