Abstract
PURPOSE: To determine the retest variability of mesopic and two-color dark-adapted (DA) fundus-controlled perimetry (FCP), to evaluate the predictive value of patient reliability indices, and to analyze the extent of impairment of rod- and cone function in neovascular age-related macular degeneration (nAMD). METHODS: A total of 50 eyes of 50 patients with nAMD (mean age, 76.1 years) and 70 eyes of 70 age-similar normal subjects underwent multimodal imaging as well as mesopic and DA two-color perimetry using the S-MAIA device. A subset of patients (n = 28) underwent duplicate testing for retest reliability assessment. Mixed models were used for analysis of the hierarchical data. RESULTS: In eyes with nAMD, the coefficient of repeatability was (mean ± standard deviation [SD]) 5.99 ± 1.55 dB for mesopic, 6.14 ± 2.19 dB for DA cyan, and 6.06 ± 1.09 dB for DA red testing. "Patient reliability indices" explained 55%, 54.2%, and 64.2% of the variance in retest variability. The mean sensitivity loss was greater for DA cyan compared to DA red testing (cyan-red differences [mean ± SD] -2.63 ± 3.87 dB, P < 0.001). CONCLUSIONS: The relatively greater degree of DA cyan versus DA red sensitivity loss indicates preferential rod vulnerability in nAMD, and qualifies rod function-based outcomes measures as potential sensitive and early markers of treatment response in nAMD. TRANSLATIONAL RELEVANCE: The S-MAIA allows reliable testing of mesopic, DA cyan, and DA red sensitivity in patients with nAMD. Patient reliability indices may serve as eligibility criteria for clinical trials to identify patients with adequate retest reliability.