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Achromatopsia has been proposed to be a morphologically predominately stable retinopathy with rare reports of progression of structural changes in the macula. A five-grade system of optical coherence tomography (OCT) features has been used for the classification of structural macular changes. However, their association with age remains questionable. We characterized the Slovenian cohort of 12 patients with pathogenic variants in CNGA3 or CNGB3 who had been followed up with OCT for up to 9 years. Based on observed structural changes in association with age, the following four-stage classification of retinal morphological changes was proposed: (I) preserved inner segment ellipsoid band (Ise), (II) disrupted ISe, (III) ISe loss and (IV) ISe and RPE loss. Data from six previously published studies reporting OCT morphology in CNGA3 and CNGB3 patients were additionally collected, forming the largest CNGA3/CNGB3 cohort to date, comprising 126 patients aged 1–71 years. Multiple regression analysis showed a significant correlation of OCT stage with age (p < 0.001) and no correlation with gene (p > 0.05). The median ages of patients with stages I–IV were 12 years, 23 years, 27 years and 48 years, respectively, and no patient older than 50 years had continuous ISe. Our findings suggest that achromatopsia presents with slowly but steadily progressive structural changes of the macular outer retinal layers. However, whether morphological changes in time follow the proposed four-stage linear pattern needs to be confirmed in a long-term study.

Objective: To establish an automated visual acuity test (AVAT) for infants, based on preferential looking technique and controlled with remote eye tracking. To validate the AVAT in a group of healthy children. To compare AVAT visual acuity (VA) values with corresponding VA values acquired with standard tests (ST). Methods: ST, adapted for age (Keeler Acuity Cards in preverbal children and LEA symbols in verbal children), was performed to obtain monocular VA in a group of 36 healthy children. During AVAT, 9 different stimuli with grating circles that matched spatial frequencies of 9 Keeler Acuity Cards (ranging between 0.29 and 14.5 cycles per degree) were projected on a screen. Three repetitions of each stimulus were shown during 9-s intervals, interchanging with an attention grabber. The remote eye tracker was used to evaluate the proportion of time a child spent looking at each grating circle compared to a homogeneous gray background that matched the grating stimuli in average luminance. From this proportion of time, child’ s binocular VA was evaluated. Results: Ninety-seven percent (35/36) of healthy children successfully completed ST and AVAT. There was an agreement between the results of an ST and AVAT, with Lin’s concordance coefficient being 0.53 (95% CI = 0.31–0.72). A tendency was observed toward VA overestimation on AVAT for children with VA >0.4 logMAR on ST and toward VA underestimation on AVAT for children with VA ≤0.4 logMAR on ST. Conclusions: AVAT requires a minimally skilled investigator. The evaluation of better eye monocular VA on ST and binocular VA on AVAT was comparable for healthy children.