Objective: To examine monocular visual fields at the age of 10 years in children with birth weights less than 1251 g in whom severe acute-phase retinopathy of prematurity (ROP) developed in 1 or both eyes and who had random assignment of eyes to cryotherapy (treated) or no cryotherapy (control) and in a comparison group of children who did not develop ROP in the neonatal period.
Methods: Subjects were 255 children who developed severe ROP and 104 children who did not develop ROP. All were born between January 1, 1986, and November 30, 1987, and had birth weights of less than 1251 g. Goldmann perimetry was used to measure visual field extent along 8 meridia (15 degrees, 60 degrees, 105 degrees, 150 degrees, 195 degrees, 240 degrees, 285 degrees, and 330 degrees ) using the V4e and III4e stimuli. Data were analyzed by quadrant and overall solid angle of the area of the retina sensitive to the test stimulus.
Results: When blind eyes were assigned a score of 0, visual field area was 24% to 26% larger in treated eyes than in control eyes. When data from only patients with 1 sighted treated eye and 1 sighted control eye were examined, visual field area was 5% smaller in treated eyes than in control eyes. For these patients, visual field area was reduced by 30% to 37% in treated eyes and by 27% to 33% in control eyes compared with eyes with no ROP.
Conclusions: Cryotherapy preserves peripheral vision in eyes with severe ROP by preserving sight in these eyes. After excluding 70 blind treated and 102 blind control eyes, data from eyes with quantifiable visual fields indicate that cryotherapy produces a small reduction of visual field area in eyes with severe ROP. With or without cryotherapy, visual field area is considerably smaller in eyes that had severe acute-phase ROP than in eyes of preterm children who did not develop ROP.