Change of refraction in premature infants after cryotherapy for retinopathy of prematurity between the age of six months and three years.

To investigate the chronological change of refraction in premature infants after cryotherapy for retinopathy of prematurity (ROP), cycloplegic refractions had been performed at 6 months and 3 years after term in premature infants who underwent cryotherapy for ROP. The changes of refractions between the two study ages were evaluated not only in the total cryo-treated eyes, but also in the subdivided groups according to the posterior pole appearances. In the total 61 eyes of 32 premature infants, mean spherical equivalents were -4.05D vs. -5.94D (6 months vs. 3 years) (p = 0.0001). In the normal posterior pole group (48 eyes), mean spherical equivalents were -3.45D vs. -5.68D (6 months vs. 3 years) (p = 0.0000), and in the abnormal posterior pole group (13 eyes), -6.28D vs. -6.86D (6 months vs. 3 years) (p = 0.6496). These results mean that there is a myopic progressive change between 6 months and 3 years after term in the cryo-treated eyes for acute ROP and it is more evident in the eyes with normal posterior pole.