Marta A, Coelho J, Vieira R, et al. - In this retrospective cohort study involving 36 patients (49 eyes), researchers sought to compare the predictability of biometric results in patients undergoing cataract surgery combined with Ahmed glaucoma valve (AGV) implantation according to tube position. Between November 2012 and April 2020, patients who underwent phacoemulsification surgery combined with AGV implantation with the tube in the posterior (group PC) and anterior (group AC) chamber, were analyzed. The position of the tube influences biometric predictability and expected final refraction in phacoemulsification surgery combined with AGV implantation.