Fig. (3) Bonferroni posthoc analysis revealed that topical treatment with Prostaglandin Analogues (PG) significantly increases iris thickness at the level of the Sphincter Muscle Region (SMR) of patients with POAG or OHT as compared to affected patients treated with eyedrops not containing PG or alpha adrenergic agonists (NOPG, p<0,0001) or to control healthy subjects (CTRL, p<0,0001).