To determine possible side effects of diode laser photocoagulation for threshold retinopathy of prematurity in eyes with tunica vasculosa lentis.

In a prospective clinical study, threshold retinopathy of prematurity was treated in 14 eyes of seven consecutive preterm infants with tunica vasculosa lentis (birth weight, 480 to 980 g; mean ± S.D., 777 ± 175 g; gestational age, 24 to 27 weeks; mean ± S.D., 25.7 ± 0.9 weeks) by using the diode laser indirect ophthalmoscope. Main outcome measure was the incidence of adverse treatment effects. Follow-up included anterior segment examination with a hand-held slit lamp and ranged from seven to 17 months (12.6 ± 3.5 months).

The tunica vasculosa lentis did not interfere with photocoagulation in any of the 14 eyes. Laser power ranged from 200 to 400 mW (260 ± 52 mW). Duration of a single spot was 200 msec. Number of burns ranged from 1,060 to 2,132 (1,556 ± 315). Retinopathy of prematurity regressed in all eyes, and the outcome was a flat, attached retina. A small amount of postoperative anterior chamber bleeding was noticed in one eye (7% of the eyes, 14% of the patients). There were neither lenticular opacities nor cataract formation.

Diode laser photocoagulation with the laser indirect ophthalmoscope can be used safely in eyes with tunica vasculosa lentis. At the laser energy levels used in our study, no transient lens opacities or cataract formation occurred. However, the results of this study are limited by a relatively small number of patients and a relatively short follow-up.