Refractive Changes among Diode Laser-treated Retinopathy of Prematurity Patients: A Retrospective Study

The purpose of this study was to assess the refractive outcomes of patients who underwent indirect laser photocoagulation for prethreshold type 1 retinopathy of prematurity (ROP) and high-risk type 2 prethreshold ROP in comparison to conservatively managed low-risk prethreshold type 2 ROP.

A retrospective analysis was carried out on infants screened for ROP between the years 2015 and 2020. Surviving children who had developed ROP in one or both eyes and received diode laser photocoagulation and those with conservatively managed regressed type 2 ROP who underwent at least one cycloplegic retinoscopy were included in the study.

A total of 144 patients were screened for ROP between 2015 and 2020 at our institution. One hundred and thirty patients (260 eyes) fulfilled the study criteria and were included in this study. The treated group consisted of 132 eyes of 66 infants, of which 38 (14.6%) eyes had prethreshold type 1 ROP while 94 (36.2%) eyes had high-risk prethreshold type 2. The nontreated control group consisted of 128 (49.2%) eyes of 64 infants with low-risk type 2 prethreshold ROP. Earlier prematurity was found to be a significant determinant of the mean change in spherical equivalent among different gestational age groups (P = 0.035). In our cohort, we found that myopia is significantly related to Zone II ROP in comparison to Zone III ROP in the treated eyes (22% vs. 9%) (P = 0.002). No statistically significant difference was found in the final refraction among the treated eyes in relation to the birth weight or stage of prematurity.

In the present study, the majority of patients who were treated with diode laser for ROP had favorable anatomical and refractive outcomes. In contrast to previous studies that had suggested a trend toward myopia in laser-treated patients, in our study, the majority (71%) were hyperopes. This study suggests that other factors such as the stage and zone of ROP possibly contribute more to the development of myopia than the laser photocoagulation itself.