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Comparison of intraoperative wavefront aberrometry and preoperative biometry for intraocular lens calculation in post refractive surgery eyes

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First Author: L.Gouvea USA

Co Author(s):    C. Brown   K. Sioufi   R. Penatti   G. Waring IV   K. Maia Rocha        

Abstract Details


To compare the prediction error in post corneal refractive surgery eyes using the latest methods for IOL power calculation (IOLMaster 700 and Barrett True-K formula) with that of ORA intraoperative wavefront aberrometry.


Storm Eye Institute, Medical University of South Carolina


Patients with history of hyperopic or myopic ablation who underwent phacoemulsification between April 2015 and December 2019 were enrolled in the study. All eyes underwent pre-operative optical biometry (IOLMaster® 700) and intraoperative biometry (ORA). IOL power was calculated using the Barrett-True K formula for post-hyperopic and post-myopic ablation. Comparison between ORA-recommended, Barrett-True K recommended, and IOL implanted was conducted. The error in the predicted refraction was calculated as the difference between the actual postoperative refractive outcome and the predicted refraction for each formula or method. A group of nonrefractive eyes was used as control.


60 post hyperopic ablation eyes, 70 eyes with history of myopic ablation and 80 controls were included in this study. In the hyperopic group, the lowest mean prediction error (PE) was observed with the ORA-recommended IOL (0.030.57), compared to IOL implanted (0.1080.65), and Barrett-True K (0.3960.63; p=0.03). In the myopic group, the highest mean PE was observed with Barrett-True-K formula (0.460.79), followed by ORA-recommended (0.0610.48) and IOL implanted (0.060.48; p=0.001). In the control group, no statistically significant difference was seen in IOL calculations using Barrett Universal II (-0.010.66) and ORA (-0.060.77; p=0.69).


Intraoperative biometry may be an important instrument to improve postoperative refractive outcomes in post refractive patients, whereas in normal eyes, standard IOL calculation using Barrett Universal II yields suitable refractive outcomes.

Financial Disclosure:

... receives consulting fees, retainer, or contract payments from a competing company, ... research is funded, fully or partially, by a company producing, developing or supplying the product or procedure presented

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