Abstract
Purpose :
Although plus disease is the most important parameter for treatment-requiring retinopathy of prematurity (ROP), the prognostic value of pre-plus disease, which has been defined as retinal vascular abnormalities insufficient for plus disease but possessing more arterial tortuosity and venous dilation than normal, has not been extensively studied. The purpose of this study is to describe and analyze the natural course of pre-plus disease, and to compare its predictive value with other known ocular parameters.
Methods :
A multicenter prospective cohort study was performed including infants screened for ROP at one of 6 major ROP centers in the United states. Information was collected describing demographics of included infants, classification of ROP at each exam, and final outcome of ROP including lowest zone, highest stage, and presence of plus or pre-plus disease. Variables reflecting time-series events were generated from session data and analyzed. Multivariate logistic regression was performed in order to determine odds ratios for factors occurring prior to a determination of treatment-requiring disease.
Results :
A total of 493 eyes from 493 preterm infants with mean gestational age (GA) of 27.15 ± 2.18 weeks were analyzed. Of 91 eyes diagnosed as pre-plus at least once during the screening period, 36 eyes (39.6%) required treatment. The stage and zone at which pre-plus was first diagnosed were not significantly associated with progression rate to treatment-requiring disease. The progression rate showed a negative correlation to PMA at the first diagnosis of pre-plus with borderline significance (Pearson correlation coefficient = -0.57, p=0.06). Multivariate logistic regression showed pre-plus disease to be predictive of treatment outcome (OR 3.49, CI [1.81,6.79]), and to have greater predictive effect than zone I (OR 2.17, CI [1.20,3.93]) or stage 3 disease (OR 0.25, CI [0.08,0.68]).
Conclusions :
A high proportion of eyes with pre-plus disease showed progression to treatment-requiring ROP. When pre-plus disease is shown early during the screen period, it is more likely that the eyes will develop treatment-requiring ROP. Use of the pre-plus distinction varies between clinicians, but this evidence of predictive power of the classification indicates that its expanded use has potential to improve staging of ROP patients during diagnosis.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.