Asymmetry of Retinopathy of Prematurity Border in the Telemedicine Approaches to Evaluating Acute-Phase Retinopathy of Prematurity Study.

PURPOSE

To measure the location of the retinopathy of prematurity (ROP) border in a sample of premature infants developed ROP and to determine the location for predicting subsequent development of referral-warranted ROP (defined as stage 3 ROP, zone I ROP, or plus disease) or treated ROP.

DESIGN

Secondary analysis of data from an observational cohort study, the Telemedicine Approaches to Evaluating Acute-Phase Retinopathy of Prematurity study.

PARTICIPANTS

Infants with birth weight (BW) of less than 1251 g with at least 1 examination and imaging session at 34 weeks postmenstrual age (PMA) or younger with ROP not meeting referral-warranted ROP and at least 1 subsequent examination at 36 weeks PMA or older.

METHODS

The 5-image set from the first imaging session for each eligible eye was mosaicked, and measurements of the ROP border were made using Image J. Measurements were compared among 3 groups of eyes with ROP: (1) those that never developed referral-warranted ROP or received treatment, (2) those that developed referral-warranted ROP but did not receive treatment, and (3) those that received treatment.

MAIN OUTCOME MEASURES

Referral-warranted ROP and treated ROP.

RESULTS

Three hundred seventeen eyes from 217 infants with mean BW of 755 g, mean gestational age (GA) of 25 weeks, and mean PMA of 33 weeks at first examination met study criteria. Of 211 eyes (66.6%) with sufficient-quality images for grading, 147 (69.7%) did not develop referral-warranted ROP or receive treatment, 36 (17.1%) developed referral-warranted ROP not requiring treatment, and 28 (13.3%) received treatment for ROP. Among all eyes, the disc-to-ROP border distance followed a consistent pattern, with nasal less than inferior less than superior less than temporal. In multivariate analysis adjusted by BW and GA, nasal ROP border distance was a significant predictor of the subsequent development of ROP that was treated (odds ratio, 0.86 for every 10-pixel increase in distance; P = 0.002).

CONCLUSIONS

Retinopathy of prematurity is located asymmetrically around the optic disc and is closest to the optic disc nasally. Location of ROP nasally at first imaging is a significant predictor for subsequent development of ROP that was treated.