Refractive errors and ocular motility disorders in preterm babies with and without retinopathy of prematurity.

Ocular motility, refraction and visual acuity (VA) were evaluated at the age of 4 years in 136 preterm infants with gestational ages (GAs) at birth of less than 32 weeks. Group 1 (non-retinopathy of prematurity, ROP) included 87 children that had never developed ROP. Group 2 contained 19 children whose ROP had regressed spontaneously. Group 3 (cryo-ROP) was composed of 30 patients who had undergone cryotherapy for severe ROP. Strabismus was found in 13.9% of the total population. chi(2) analysis revealed that strabismus was significantly (p < 0.01) associated with prematurity (i.e. GA <29 weeks), ROP and cryotherapy. Myopia of more than 3 dpt was significantly (p < 0.001) more common in the cryo-ROP infants than in the regressed-ROP and non-ROP groups. The distribution of hypermetropia was similar in all three groups. VA was measured with the E chart. Of the 272 eyes examined, 251 (92.3%) displayed VA of more than 20/25. The majority of these eyes were from the non-ROP group (65.4%), 15.3% had regressed ROP and 21.1% belonged to the cryo-ROP group. Fifteen eyes (8 non-ROP, 3 regressed ROP and 4 cryo-ROP) presented VAs between 20/25 and 20/60. VA of less then 20/60 was found in 6 eyes (2 non-ROP, 1 regressed ROP, 3 cryo-ROP). Cryotherapy did not appear to preclude the development of good VA.