Visual outcome in 2-year-old children after cryocoagulation of threshold retinopathy of prematurity

Background: The results of the Cryo-ROP group showed that cryotherapy significantly reduces the rate of adverse morphological and functional outcome of eyes with threshold retinopathy of prematurity. Structural status and visual acuity of 48 eyes which consecutively underwent cryocoagulation in our hospital between 1990 and 1994 were examined at 2 years corrected gestational age. Method: Visual acuity and fundus morphology were examined by Teller acuity-cards test, retinoscopy, orthoptic status and fundus examination. A favourable grating acuity was defined as greater than or equal to 2.2 cy/degrees, a favourable morphology as no pathological or mild findings at the level of the posterior pole or stage 4 a. Results: Fifty-six % of cases reached a quantifiable grating acuity between 0.32 and 13.0 cy/degrees, 42% reached a favourable functional outcome, and 69% of the eyes had a morphologically favourable outcome. Fifty-five % of the measurable eyes were myopic, and 29% had a high myopia greater than or equal to -6.0 D. 47% showed a heterotropia. Conclusions: Our results show a discrepancy between morphological and functional outcome. Especially for zone 1 eyes, cryocoagulation of the avascular retina does not seem to allow a favourable morphological and functional outcome.