The contribution of GB Bietti Foundation was supported by the Italian Ministry of Health and Fondazione Roma.
The authors have no proprietary interest in the subject of this paper except for K.J.H. who licenses the registered trademark name Hoffer to Carl-Zeiss Meditec (IOLMasters), Haag-Streit (LenStar), Oculus (Pentacam AXL), Movu (Argos), Nidek (AL-scan), Tomey (OA-2000), Topcon EU/Visia Imaging (Aladdin), Ziemer (Galilei G6), and all A-scan biometer manufacturers to insure accuracy of formula programming. G.S. declares that there is no conflicts of interest to disclose.