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Comparison of refractive outcomes using Scheimpflug Holladay equivalent keratometry or IOLMaster 700 keratometry for

Mustafa Aksoy¹, Leyla Asena², Sirel Gür Güngör²

¹Department of Ophthalmology, Faculty of Medicine, Yüksek Ihtisas University, Ankara, Turkey. mustafa-aksoy@hotmail.com.

International Ophthalmology

|March 18, 2021

Summary

Both Pentacam equivalent keratometry readings (EKR) and IOLMaster 700 keratometry (K) values provide comparable outcomes for intraocular lens (IOL) power calculations. The IOLMaster 700 K values with the Holladay-II formula offered the most accurate refractive prediction.

Keywords:

Cataract surgery Equivalent keratometry readings IOLMaster 700 Optical Biometry Pentacam

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Area of Science:

Ophthalmology
Biomedical Engineering
Optics

Background:

Accurate intraocular lens (IOL) power calculation is crucial for achieving desired postoperative refractive outcomes in cataract surgery.
Keratometry measurements are a key input for modern IOL power calculation formulas.
Comparing different keratometry devices and measurement zones is essential for optimizing refractive predictability.

Purpose of the Study:

To compare the postoperative refractive error results obtained using Pentacam equivalent keratometry readings (EKR) versus IOLMaster 700 keratometry (K) values for IOL power calculation.
To evaluate the interchangeability of keratometry data from two different devices in standard IOL power calculation formulas.

Main Methods:

A retrospective study of 54 eyes from 31 cataract surgery patients.
Preoperative measurements using IOLMaster 700 and Pentacam.
Comparison of IOLMaster 700 K values (horizontal/vertical) and Pentacam EKR values (2, 3, and 4.5 mm zones).
Calculation of predictive refractive error (PRE) using Holladay-II, SRK/T, Haigis, and Hoffer-Q formulas with both measurement sets.
Analysis of absolute refractive error (ARE) to determine prediction accuracy.

Main Results:

No significant difference in predicted refractive error (PRE) was found when using IOLMaster 700 K values versus Pentacam EKR 4.5 mm values across the tested formulas (p > 0.05).
No significant difference was observed between actual postoperative refractive error (APRE) and absolute refractive error (ARE) (p = 0.124).
The Holladay-II formula using IOLMaster 700 K values resulted in the closest refractive estimate, indicated by the lowest mean ARE (p = 0.271).

Conclusions:

Pentacam EKR 4.5 mm measurements and IOLMaster 700 K measurements are interchangeable for IOL power calculations.
The IOLMaster 700 K values, when utilized with the Holladay-II formula, provide the most predictive measurement for refractive outcomes.