Resumen de Intraocular lens power calculation after myopic excimer laser surgery with no previous data
Juan Carlos Mesa Gutiérrez, Antonio Rouras López, Isabel Cabiró Badimón, Vicente Amías Lamana, José Porta Monnet, L. Solanas García
ABSTRACT: How many ways are there to calculate intraocular lens (IOL) power in eyes that have myopic laser in situ keratomileusis (LASIK)? The list is long, and growing. As is always the case when there are several solutions to a problem, none is perfect.
In this review, we describe the most reliable methods in the worst scenario: no data prior to LASIK available.When no preoperative corneal power and refractive change are available the lowest mean absolute error is achieved with the methods of Masket, Seitz/Speicher/Savini, Shammas, and Camellin/Calossi. When preoperative corneal power is unknown but the surgically induced refractive change is known the lowest mean absolute error is achieved with the Masket method followed by the the Savini method, Speicher/Seitz method modified by Savini, and Shammas no-history method.
Ideally, it would be optimal to have a spreadsheet that allows the clinician to insert all values available. The various formulas would then be calculated automatically. When faced with a range of values for the IOL power, you’d better look for values that are consistent with at least one other reading. Values that select higher IOL powers are preferable, leaving the patient slightly myopic rather than hyperopic.
Resolution of this problem will require a method for accurately measuring posterior corneal power or a technique for adjusting IOL power after implantation. Until then, surgeons are faced with performing multiple calculations to ‘‘guesstimate’’ the correct IOL for patients who, by their original decision to have LASIK, have demonstrated that they have above-average refractive demands.
