The authors performed cycloplegic refractions in 180 eyes of 99 premature infants at the age of 6 months to evaluate the incidence and the degree of myopia according to the development and disease course of retinopathy of prematurity (ROP) and to investigate the effect of cryotherapy on the refractive error. The incidences of myopia were not different between premature infants without ROP and premature infants with spontaneously and totally regressed ROP (36.3%, 25.5%), and the degrees of myopia were low in both groups (-1.76 D, -2.25 D). In premature infants with totally regressed ROP after cryotherapy, the incidence of myopia was high (75.5%) but the degree of myopia was low (-3.03 D). In premature infants with cicatricial ROP, cryotreated or not, both the incidence and the degree of myopia were high (93.9%, -5.50 D). It is suggested that cryotherapy increases the incidence of myopia but the degree of myopia induced by cryotherapy is low.
PIP: Little is known about the incidence of myopia in premature infants with spontaneously regressed retinopathy of prematurity (ROP) without cicatricial changes or the effect of cryotherapy on refractive errors. The authors therefore report findings from cycloplegic refractions conducted in 180 eyes of 99 premature infants at age 6 months in order to evaluate the incidence and degree of myopia according to the development and disease course of ROP and to investigate the effect of cryotherapy on the refractive error. No differences were found between incidences of myopia in premature infants without ROP and premature infants with spontaneously and totally regressed ROP. The degree of myopia was low in both groups. A 75.5% incidence of myopia was observed in premature infants with totally regressed ROP after cryotherapy, but the degree of myopia was low. A 93.9% incidence of high degree myopia, however, was found among premature infants with cicatricial ROP regardless of whether or not they received cryotreatment. These findings suggest that cryotherapy increases the incidence of myopia, but the degree of myopia induced by this treatment is low.