Screening for retinopathy of prematurity: results of a 7-year study of underweight newborns.

Background: Retinopathy of prematurity (ROP) is a serious complication of treatment and extension of survival in premature infants and leads to blindness unless recognized and treated early. An ROP prospective screening survey was performed, enrolling all premature newborns weighing <2000 g at delivery.
Methods: A total of 2014 infants had a retinal evaluation by indirect ophthalmoscopy at 4-6 weeks of age. If any ROP stage was detected, the patient was followed periodically to assess treatment. All premature infants with threshold retinopathy were treated by transscleral cryotherapy at the time of detection.
Results: We found 449 infants (22.2%) with ROP in any stage, and 230 (11.42%) with threshold retinopathy who underwent cryotherapy. In the 500-1000 g group (n = 334), 48.2% had ROP in any stage and 92 (27.5%) had threshold retinopathy. In the 1001-1500 g group (n = 1374), 257 (18.7%) had any ROP stage and 122 (8.8%) had stage 3. In the 1501-2000 g group, 306 neonates were evaluated, 31 (10%) had any ROP stage and 16 (5.2%) underwent cryotherapy. A total of 198/230 infants (86%) with threshold retinopathy who received cryotherapy had complete recovery, but 5% developed unilateral and 9% bilateral retinal detachment. There were no complications related to anesthesia.
Conclusions: Overall ROP rate was 2.68/1000 deliveries and 22.2% of premature infants <2000 g had any ROP stage, 11.42% with retinal detachment risk received cryotherapy with 86% successful results.