The results of treatment of retinopathy of prematurity by laser photocoagulation

PURPOSE: The subject of paper was to assess: 1. The child's age, when the threshold retinopathy is diagnosed. 2. To estimate the correlation between gestational, corrected and chronological age of the child at the time of the ophthalmologic surgery. 3. To estimate the effect of the treatment on the ROP's regress and to find the risk factors of the progress of retinopathy despite of the treatment. MATERIAL AND METHODS: We studied 103 children treated because of the retinopathy of prematurity. The mean chronological age at the time of the surgery was 74,8 day +/- 18,3 and corrected age was 37,7 Hbd +/- 3,2. To assess the risk factors of the progress of the ROP despite the treatment we formed the group I- 57 children with the retinopathy's regress after the surgery and group II- 23 children with unfavorable outcome of the disease (i. e. partial or complete retinal detachment at least unilaterally). RESULTS: Fetal age correlated with corrected age at the time of the surgery (r=0,57, p<0,0001) and there was a negative correlation between gestational and chronological age at the time of the surgery (r = -0,23, p=0,02). Statistical significance was achieved by the stage of ROP before the surgery and the effects of the treatment (chi2=43,8, p<0,0001). CONCLUSIONS: The risk of the threshold retinopathy before 36 week of corrected age increases with decreased gestational age. There is positive correlation between corrected age and gestational age. The laser photocoagulation performed in appropriate time stops progression of ROP. The photocoagulation of the retinopathy is a very important risk factor of the severe vision impairment when it is made too late (more than 3rd stage of ROP). The progress of ROP despite of laser therapy is more likely in the most premature babies with small weight gain.