Plus Disease in Retinopathy of Prematurity: Should Diagnosis Be Eye-Based or Quadrant-Based?
Sang Jin Kim; John P. Campbell; Jayashree Kalpathy-Cramer; Susan Ostmo; Karyn Jonas; R.V.Paul Chan; Michael F. Chiang
Casey Eye Institute, Oregon Health & Science University
Portland, OR, United States.
Introduction: Plus disease in retinopathy of prematurity (ROP) is defined as at least 2 quadrants of retinal vascular abnormality. However, recent evidence suggests that experts often deviate from the published definition of plus disease, and it is uncertain whether experts truly perform ‘quadrant-based’ diagnosis or rather obtain a gestalt ‘eye-based’ diagnosis by assessing the overall retinal appearance, and which of these approaches is more accurate. We aimed to determine agreement between eye- vs. quadrant-based diagnosis for plus disease and accuracy and inter-grader agreement of each diagnostic approach.
Methods: As part of a prospective multicenter cohort study, 6 graders graded 197 wide-angle retinal images and their respective 4 cropped quadrant images, which were provided one at a time in random order. ‘Quadrant-based’ plus diagnosis was made when 2 or more quadrants were diagnosed as plus by combining grades of individual quadrants. ‘Eye-based’ plus diagnosis was defined as plus diagnosis based on the entire retinal images.
Results: There was variable agreement between eye- and quadrant-based plus diagnosis among the 6 graders (kappa=0.32-0.75). Quadrant-based diagnosis showed a tendency for lower agreement with reference standard diagnosis than eye-based diagnosis. Inter-grader agreement of quadrant-based diagnosis was significantly lower than that of eye-based diagnosis (kappa[95% CI] = 0.75[0.71-0.78] vs 0.55[0.51-0.59]).
Discussion: There was a discrepancy between quadrant- and eye-based analyses for plus disease diagnosis.
Conclusion: Eye-based diagnosis may be more reliable and accurate than combining individual quadrant grades for plus diagnosis in ROP. These study findings have important implications for clinical ROP management, and for education in ROP diagnosis.
References: 1. International Committee for the Classification of Retinopathy of Prematurity. The International Classification of Retinopathy of Prematurity revisited. Arch Ophthalmol. 2005;123:991-9.
2. Hewing NJ, Kaufman DR, Chan RV, Chiang MF. Plus disease in retinopathy of prematurity: qualitative analysis of diagnostic process by experts. JAMA Ophthalmol. 2013;131:1026-32.
3. Campbell JP, Ataer-Cansizoglu E, Bolon-Canedo V, et al. Expert Diagnosis of Plus Disease in Retinopathy of Prematurity From Computer-Based Image Analysis. JAMA Ophthalmol. 2016;134:651-7.