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Evaluation of spherical equivalent outcomes of ray tracing based IOL power calculation using exact IOL design information compared with triple optimized Haigis formula

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Session Details

Session Title: Cataract Surgery Outcomes: IOL Power Calculations

Session Date/Time: Sunday 08/10/2017 | 14:30-16:00

Paper Time: 14:30

Venue: Meeting Center Room I

First Author: : N.Hirnschall AUSTRIA

Co Author(s): :    O. Findl   T. Buehren   M. Trost              

Abstract Details


To evaluate spherical equivalent (SEQ) post-op refractive outcomes of a new raytracing based IOL power calculation method using IOLMaster 700 individualized eye model (IEM) data, a physical lens position (PLP) predictor, retinal image quality metrics (RIQM) criteria for IOL power selection and exact CT Asphina 409 MP IOL design information in comparison with Haigis formula.


Hanusch Hospital, Vienna, Austria


Post-operative refractive outcome was assessed at a minimum of 4 weeks after surgery. Additionally, IOLMaster 700 raw data was collected pre- and at least 4 weeks post-surgery. Carl Zeiss Meditec internal prototype software was applied to generate individual eye models from pre- and post-surgical data including central corneal topography of front and back surfaces, anterior chamber depth, lens or IOL thickness and axial length. Retrospective raytracing based IOL power calculation was performed using RIQM criteria for IOL power selection in an iterative procedure and retinal Image simulations were performed.


Results present preliminary data of 49 eyes of 49 patients. Data collection is ongoing. Median- and mean absolute prediction error of SEQ was 0.02 D and 0,38D for raytracing and 0,12D and 0,42D for Haigis formula respectively. Minimum to maximum deviation of SEQ from target was -1,03D to +1,00D for raytracing and -1,06D to +1,13D for Haigis formula respectively. Prediction errors larger ±1.00D away from target refraction was lower in the raytracing group (n = 2) compared with the Haigis group (n = 13).


Raytracing based IOL power calculation using IOLMaster 700 IEM data, PLP prediction, RIQM based IOL power selection and exact IOL design information shows promising preliminary results not only for SEQ outcome performance but also for surgeon and patient education as well as management of patient expectations.

Financial Disclosure:

is employed by a forNONEprofit company with an interest in the subject of the presentation, receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented

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