Improving IOL power calculations

Article

By using calibrated axial length readings obtained with partial optical coherence interferometry (PCI) and intraocular lens (IOL) power calculation formulas incorporating anterior chamber depth (ACD) prediction algorithms, the accuracy of power calculations can be greatly improved, according to study published in the February issue of Acta Ophthalmologica Scandinavia.

By using calibrated axial length readings obtained with partial optical coherence interferometry (PCI) and intraocular lens (IOL) power calculation formulas incorporating anterior chamber depth (ACD) prediction algorithms, the accuracy of power calculations can be greatly improved, according to study published in the February issue of Acta Ophthalmologica Scandinavia.

Thomas Olsen from the University Eye Clinic, Aarhus Kommunehospital, Aarhus, Denmark, calculated the IOL power for 461 consecutive cataract patients using both PCI and ultrasound. The accuracy of the results from each technique were compared. Predictions were calculated using both a recently published 5–variable method and the Haigis 2–variable method. All calculations were optimized in retrospect to account for systematic errors, including IOL constants and other off–set errors.

The average absolute IOL prediction error (observed minus expected refraction) was 0.65 D with ultrasound and 0.43 D with PCI using 5–variable ACD prediction method (p‹0.00001). The number of predictions within ±0.5 D, ±1.0 D and ±2.0 D of the expected outcome was 62.5%, 92.4% and 99.9% with PCI, compared with 45.5%, 77.3% and 98.4% with ultrasound (p‹0.00001), respectively. The 2–variable ACD method resulted in an average error in PCI prediction of 0.46 D, which was found to be significantly higher than the 5–variable method (p‹0.001).

Olsen concluded that the accuracy of IOL power calculations is significantly improved when using PCI and modern calculation formulas that incorporate the latest generation ACD prediction algorithms.

Related Videos
ARVO 2024: Andrew D. Pucker, OD, PhD on measuring meibomian gland morphology with increased accuracy
 Allen Ho, MD, presented a paper on the 12 month results of a mutation agnostic optogenetic programme for patients with severe vision loss from retinitis pigmentosa
Noel Brennan, MScOptom, PhD, a clinical research fellow at Johnson and Johnson
ARVO 2024: President-elect SriniVas Sadda, MD, speaks with David Hutton of Ophthalmology Times
Elias Kahan, MD, a clinical research fellow and incoming PGY1 resident at NYU
Neda Gioia, OD, sat down to discuss a poster from this year's ARVO meeting held in Seattle, Washington
Eric Donnenfeld, MD, a corneal, cataract and refractive surgeon at Ophthalmic Consultants of Connecticut, discusses his ARVO presentation with Ophthalmology Times
John D Sheppard, MD, MSc, FACs, speaks with David Hutton of Ophthalmology Times
Paul Kayne, PhD, on assessing melanocortin receptors in the ocular space
Osamah Saeedi, MD, MS, at ARVO 2024
© 2024 MJH Life Sciences

All rights reserved.