This work presents all aspects of IOL power calculations by international masters of the field. In the past, patients quietly accepted needing an eyeglass prescription after cataract surgery. That is no longer true. This textbook explains just why a more complex evaluation of the eye is needed, and will describe the state of the art in the technology used to ensure the best possible results today. IOL power calculation is a complex and important subject. A number of new formulas have come up for cataract and refractive surgeons which deliver good outcomes and provide another avenue to validate IOL selections. This international book of IOL power calculations covers all aspects of calculations from normal cornea to after refractive surgery, in Phaco/Microphaco, on irregular corneal surgace, in phakic IOLs, in corneal scarring and astigmatism, and in pediatric cataract surgery.