Purpose To assess contrast sensitivity (CS) for detecting visual changes in suspected POAG patients. Methods CS was measured foveally at photopic conditions and peripherally at mesopic conditions using sinusoidal gratings of 4 cycles/degree. In experiment 1, foveal and peripheral CS were assessed in suspected POAG patients and age-matched healthy control subjects. In experiment 2, foveal CS was assessed in early POAG patients age-matched with suspected POAG group. Analysis was done considering two age ranges (Under and Over 50 years of age). Correlations between CS and clinical parameters were evaluated. Results Peripheral CS was decreased only for older POAG suspect patients from the control group (Over 50: p = 0.008. Under 50: p = 0.566). Foveal CS was reduced in POAG suspect participants for both age ranges (Over 50: p = 0.028. Under 50: p < 0.001) and in early POAG patients (Under 50: p = 0.001; Over 50: p < 0.001), both compared to the control group. Foveal CS was lower in early POAG compared to POAG suspect for older patients (Over 50: p = 0.019. Under 50: p = 0.824). Foveal CS was correlated with cup-disc ratio in early POAG patients (Early: p < 0.001. Suspect: p = 0.766) and with age in both patient groups (Early: p = 0.001. Suspect: p = 0.002). Conclusion CS is affected in patients with a high risk of developing POAG and recently diagnosed. Our results suggest that CS could serve as a screening tool, detecting early damage even before structural changes occur.

The authors have declared no competing interest.

This work was funded by the Agencia I+D+i [grant code PICT 2019-03673], the Consejo Nacional de Investigaciones Cientificas y Tecnicas [grant codes PIBAA-1234 and PIP-2721] and the German Research Foundation (DFG) [project number 222641018 - SFB/TRR 135 TPs C2 and B2].

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