CALCULATION OF IOL POWER

🔬 CALCULATION OF IOL POWER (BIOMETRY)::
🔰 The most common method of determining IOL power uses a regression formula called ‘SRK (Sanders, Retzlaff and Kraff) formula’.
🔰 The formula is P = A – 2.5L – 0.9K, where:
✒ P is the power of IOL.
✒ A is a constant which is specific for each lens type.
✒ L is the axial length of the eyeball in mm, which is determined by A-scan ultrasonography.
✒ K is average corneal curvature, which is determined by keratometry.
🔰 The ultrasound machine equipped with A-scan and IOL power calculation software is called ‘Biometer’.