Toric Intraocular Lens Calculation Following Corneal Refractive Surgery Using The Goggin Nomogram And Ascrs Website “Average” Value.
Published 2024 - 42nd Congress of the ESCRS
Reference: FP27.08 | Type: Free paper | DOI: 10.82333/m8hr-gy37
Authors: Zea Munro* 1 , Michael Goggin 2
1Ophthalmology,The Queen Elizabeth Hospital,Adelaide,Australia, 2Ophthalmology,The Queen Elizabeth Hospital,Adelaide,Australia;Advanced Adelaide Eye Care,Adelaide,Australia;Ophthalmology,University of Adelaide,Adelaide,Australia;South Australian Institute of Ophthalmology,Adelaide,Australia
Purpose
To describe a method of toric intraocular lens (IOL) cylinder power calculation in eyes that have previously undergone keratorefractive surgery by applying a nomogram to adjust for posterior corneal and other non-corneal astigmatic effects (the Goggin Nomogram) in conjunction with The American Society of Cataract and Refractive Surgery (ASCRS) post-keratorefractive IOL power calculator.
Setting
Publicly funded hospital and a private clinic in Adelaide, South Australia.
Methods
All eyes that underwent cataract surgery with a history of keratorefractive surgery from the implementation of the nomogram were analyzed. IOLMaster 700 keratometric astigmatism was adjusted for posterior corneal and other non-corneal astigmatic effects with the Goggin Nomogram. Toric IOL powers were established by two hypothetical spherical IOL calculations using the American Society of Cataract and Refractive Surgeons (ASCRS) post-keratorefractive IOL calculator using adjusted keratometric values provided by the Goggin Nomogram. The “average” powers from the website were used. Postoperative refractive outcomes were vector analyzed.
Results
A total of 36 consecutive eyes were included. The mean absolute astigmatism power prediction error was 0.19D ± 0 .16. The astigmatism correction index was 1.06. An astigmatism prediction error of 0.50D or less was achieved in 34 eyes (94.4%). The postoperative spectacle plane refractive astigmatism mean was 0.28D ± 0.22 with 35 eyes (97.2%) measuring 0.5D of refractive astigmatism or less and 36 eyes (100%) 0.75D or less.
Conclusions
The method described provides the highest accuracy of toric IOL cylinder power calculation following corneal refractive surgery published to date to our knowledge.