Kim JS, et al. - Researchers compared the eye-based vs quadrant-based diagnosis of plus disease in retinopathy of prematurity and provided insight for ophthalmologists about the diagnostic process. Lower reliability and accuracy was seen in graders using quadrant-based diagnosis combining grades of individual quadrants than with eye-based diagnosis, thereby, suggesting that eye-based diagnosis has advantages over quadrant-based diagnosis. They noted its implications for more precise definitions of plus disease regarding the criterion of 2 or more quadrants, clinical care, computer-based image analysis, and education for all ophthalmologists who manage retinopathy of prematurity.

Methods

• Authors, in this multicenter cohort study developed a database of 197 wide-angle retinal images from 141 preterm infants from neonatal intensive care units at 9 academic institutions (enrolled from July 2011 to December 2016).
• They assigned each image a reference standard diagnosis based on consensus image-based and clinical diagnosis.
• From February 2017 to September 2017, data analysis was performed.
• Each of the 4 quadrants (cropped images) of the 197 eyes (quadrant-based diagnosis) as well as the entire image (eye-based diagnosis) were independently diagnosed by 6 graders .
• They displayed images individually, in random order.
• When 2 or more quadrants were diagnosed as indicating plus disease by combining grades of individual quadrants post hoc, quadrant-based diagnosis of plus disease was made.
• Main outcomes and measures were intragrader and intergrader reliability (absolute agreement and κ statistic) and accuracy compared with the reference standard diagnosis.

Results

• As per data, out of the 141 included preterm infants, 65 (46.1%) were female and 116 (82.3%) white, and the mean (SD) gestational age was 27.0 (2.6) weeks.
• Findings suggested that there was variable agreement between eye-based and quadrant-based diagnosis among the 6 graders (Cohen κ range, 0.32-0.75).
• Compared with eye-based diagnosis, 4 graders demonstrated underdiagnosis of plus disease with quadrant-based diagnosis (by McNemar test).
• Results demonstrated that intergrader agreement of quadrant-based diagnosis was lower than that of eye-based diagnosis (Fleiss κ, 0.75 [95% CI, 0.71-0.78] vs 0.55 [95% CI, 0.51-0.59]).
• Researchers noted that compared with the reference standard, the accuracy of eye-based diagnosis diagnosis was substantial to near-perfect, whereas that of quadrant-based plus disease diagnosis was only moderate to substantial for each grader.