The melanopsin-controlled PIPR was significantly reduced in early and late glaucoma patients compared to controls with the quadrant (SNF: F3,62 = 25.37, p < 0.0001; INF: H = 42.05, p < 0.0001) and full field stimulation (H = 37.21, p < 0.0001) (Fig. 7). Here, OPN4 is linked to glaucoma.