Abstract
Background: Myopic maculopathy (MM) is one of the major causes of visual impairment and irreversible blindness in eyes with PM. However, the classification of each type of lesion associated with MM has not been determined. Recently, a new MM classification system was proposed, known as the ATN grading and classification system, which was based on the fundus photographs and OCT images, including three variable components: atrophy (A), traction (T), and neovascularization (N). Hence, this study aimed to perform an independent interobserver and intraobserver agreement evaluation of the recently developed ATN grading system for MM. Methods: This was a retrospective study. Fundus photographs and the optical coherence tomography (OCT) images of 125 patients (226 eyes) with various of MM were evaluated and classified using the ATN grading of the new MM classification system by four evaluators (2 attending ophthalmologists and 2 ophthalmic residents). All cases were repeatedly evaluated by the same evaluators after an interval of 6 weeks. The Kappa coefficient (κ) and 95% confidence interval (CI) were used to determine the interobserver and intraobserver agreement.Results: The interobserver reliability was substantial when considering the maculopathy type (A, T, and N). The weighted Fleiss κ values for each MM type (A, T, and N) were 0.651 (95% CI: 0.602–0.700), 0.734 (95% CI: 0.689–0.779), and 0.702 (95% CI: 0.649–0.755), respectively. The interobserver agreement when considering the sub-types was good or excellent, except for stages A1, A2, and N1 which weighted κ value was less than 0.6, with a moderate agreement. The intraobserver reproducibility of types or sub-types was excellent, with κ>0.8. No significant differences were observed between attending ophthalmologists and residents in the interobserver reliability and intraobserver reproducibility.Conclusions: The ATN classification allows an adequate agreement among ophthalmologists with different qualifications and by the same observer on separate occasions. Future prospective studies should further evaluate whether this classification can be better implemented at clinical decision-making and disease progression assessment.
Intra and Inter-observer Concordance of a New Classification System for Myopic Maculopathy
