Acquired cataracts after argon laser photocoagulation for retinopathy of prematurity

Abstract

Purpose : Our purpose was to determine the incidence of cataract after argon laser photocoagulation of the retina in infants with retinopathy of prematurity (ROP). Methods : We reviewed medical records of 189 consecutive infants undergoing argon laser photocoagulation for acute ROP between 1993 and 1996. Birth weight, estimated gestational age at birth, chronologic and postconceptional ages at the time of treatment, ROP outcome, and the postoperative occurrence of cataract were recorded. Results : A total of 374 eyes in 189 infants were treated for threshold ROP. Mean birth weight was 916 gm (range 480 to 2500 gm), mean postconception age at birth was 26.4 weeks (range 23.5 to 34 weeks), and mean postconception age at surgery was 36.2 weeks (range 33 to 47 weeks). A favorable anatomic outcome occurred in 90% of eyes. However, severe macular traction, macular fold, or retinal detachment developed in 10% of eyes. A total of four eyes (1%) had cataracts. Laser-induced cataracts were diagnosed in only two eyes. A third eye had a posterior subcapsular cataract that may or may not have resulted from the laser treatment. In a fourth patient a unilateral punctate opacity judged to be visually insignificant was noted at surgery but it was not progressive. All patients who had cataracts had a persistent tunica vasculosa lentis; however, there was no statistically significant difference in the incidence of cataract formation in eyes with persistent tunica vasculosa lentis compared with eyes without it ( p = 0.057). Conclusion : Argon laser photocoagulation remains an effective alternative to transscleral cryotherapy in the treatment of threshold ROP. The incidence of cataract formation is approximately 1% and may be more likely to occur when persistent hyaloidal vessels are present on the lens.