Objective: Retinopathy of prematurity (ROP) is a significant cause of blindness in childhood worldwide. The objective of the present study is to assess long-term structural and functional results of early (received first treatment at pre-threshold stage) versus conventional treatment (treated at threshold stage) of ROP.
Material and Method: Survivors of ROP patients who underwent early or conventional treatment between 1997 and 2001 were reassessed in 2006. Functional outcome [refractive state, best corrected visual acuity (BCVA)] and anatomical outcome (retina status, ocular alignment) were compared between the two treatments using Chi-square test at p < 0.05.
Results: Of 68 patients, 39 (57.4%) returned for reassessment: 11 patients (22 eyes) were in the early treatment group and 28 patients (56 eyes) were in the conventional group. At 5 years or more, a favorable outcome (BCVA > 20/200) was achieved in 72.7% of the early group vs. 53.6% in the conventional group (p > 0.05). Normal to near normal vision (20/12-20/60 or log MAR 0.1-0.5) was significantly found in the early group (54.5% vs. 23.2%, p=0.008) and none in the early group lost vision to no light perception. Prevalence of high myopia >5 diopters and astigmatism were significantly higher in the conventional group (p = 0.001and p = 0.002 respectively). Smaller degree of ET developed significantly in the early treated group (p = 0.018) whereas ET 15 prisms or more developed exclusively in the conventional group (p = 0.04). Retinal detachment occurred in 18.1% of the early treated compared to 28.5% of the conventional groups (p = 0.402).
Conclusion: Early treatment of ROP at pre-threshold stage offered a better structural and functional outcome than at threshold. ROP patients should undergo periodic fundus examination between 6 months and 1 year of age and yearly thereafter for early detection and repair as well as yearly refraction and ocular alignment assessment to identify high refractive errors, astigmatism and strabismus for early recognition and correction.

Keywords: Retinopathy of prematurity (ROP), Early treatment, Conventional treatment, Functional outcome