Wang-Koch Adjustment (SRK/T)
Optimizes axial length for eyes > 25.0mm (SRK/T 2018 version).
Medical Specialty:
Ophthalmology
FOR PROFESSIONAL USE ONLY
This calculator is a support tool intended exclusively for health professionals. It does not replace clinical judgment. The final decision regarding diagnosis and treatment is the sole responsibility of the professional.
Patient Data
. Enter the value for Measured Axial Length in mm.
About this Calculator 💡
The Wang-Koch Adjustment (2018 version for SRK/T) is a mathematical update proposed by Drs. Wang and Koch to refine intraocular lens calculations in eyes with high myopia (> 25.0 mm). Unlike the original 2011 formula (focused on Holladay 1), this 2018 version applies specific regression coefficients intended for use with the SRK/T formula. In long eyes, SRK/T tends to overestimate lens power, leading to hyperopic errors; this adjustment reduces the measured axial length to an 'optimized axial length,' mitigating this risk. This tool should be used exclusively in conjunction with the SRK/T formula.
Reference Values
- •Optimized AL. Use this value specifically in the SRK/T formula.
- •Attention: This 2018 adjustment is intended for eyes with AL > 25.0 mm.
Formula
Calculation Methodology AL_opt = 0.8453 × AL_measured + 4.0773
Reference
Wang L, Koch DD. Modified axial length adjustment formulas in long eyes. J Cataract Refract Surg. 2018.