Refractive outcomes following cataract surgery in patients who have had myopic laser vision correction

Abstract

ObjectivePrediction errors are increased among patients presenting for cataract surgery post laser vision correction (LVC) as biometric relationships are altered. We investigated the prediction errors of five formulae among these patients.Methods and analysisThe intended refractive error was calculated as a sphero-cylinder and as a spherical equivalent for analysis. For determining the difference between the intended and postoperative refractive error, data were transformed into components of Long's formalism, before changing into sphero-cylinder notation. These differences in refractive errors were compared between the five formulae and to that of a control group using a Kruskal-Wallis test. An F-test was used to compare the variances of the difference distributions.Results22 eyes post LVC and 19 control eyes were included for analysis. Comparing both groups, there were significant differences in the postoperative refractive error (p=0.038). The differences between the intended and postoperative refractive error were greater in post LVC eyes than control eyes (p=0.012), irrespective of the calculation method for the intended refractive error (p<0.01). The mean difference between the intended and postoperative refractive error was relatively small, but its variance was significantly greater among post LVC eyes than control eyes (p<0.01). Among post LVC eyes, there were no significant differences between the mean intended target refraction and between the intended and postoperative refractive error using five biometry formulae (p=0.76).ConclusionBiometry calculations were less precise for patients who had LVC than patients without LVC. No particular biometry formula appears to be superior among patients post LVC.

Prospective Safety Evaluation of the Femtosecond Laser-Assisted Keratomileusis Procedure in Correcting Residual Ametropia in Patients After Deep Anterior Lamellar Keratoplasty

“…In addition, concerning the corneal tissue needed to perform a transplant, it is easier to employ refractive surgery [ 37 , 38 ]. Refractive surgery can also occasionally be used to alleviate adverse effects from other conditions, such as cataracts [ 39 , 40 ].…”

An Advanced Lens Measurement Approach (ALMA) in post refractive surgery IOL power calculation with unknown preoperative parameters

“…Unfortunately so far, most of the studies dealing with IOL power calculation with a and without previous refractive surgery did not consider the recommendations by Hoffer et al PLOS ONE [24,[41][42][43][44][45][46]. The reasons for this are different, some authors did not apply the zeroing of the mean error just for technical difficulties [47].…”

“…Hoffer et al suggested to avoid multiple IOLs in a study when reporting a method accuracy [24]. This is acceptable but obtaining a large database in most of the studies regarding IOL power calculation after refractive surgery is difficult, hence multiple IOL models were analyzed [22,25,[41][42][43][44]. As reported by Abulafia et al [48] more than one IOL model is appropriate when limited data are available.…”

Patient Satisfaction, Visual Outcomes, and Regression Analysis in Post-LASIK Patients Implanted With Multifocal, EDOF, or Monofocal IOLs

“…Implantation of multifocal IOLs after LASIK has remained controversial because of concerns that the corneal higher-order aberrations (HOAs) combined with the dysphotopsia of multifocal implants will significantly impact the quality of vision despite considerable improvements in postcorneal refractive surgery IOL calculations. 12 The risk of obtaining an undesirable refractive outcome from an IOL surprise still continues to discourage some surgeons from pursuing multifocal IOLs in post-LASIK cataract patients.…”