A Comparative Study on Accuracy of SRK-T And Haigis Formulas in IOL Power Calculation in Axial Myopes Undergoing...

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Refractive Surgery

Background:

• Accurate intraocular lens (IOL) power calculation is essential for optimal visual outcomes post-cataract surgery.
• Refractive surprises due to biometry errors remain a challenge, particularly in high myopic eyes.
• Evaluating IOL calculation formulas is critical for improving predictability.

Purpose of the Study:

• To compare the accuracy of the SRK-T and Haigis formulas for IOL power calculation.
• To assess the efficacy of these formulas in preventing postoperative refractive surprises in axial myopic eyes.
• To determine the preferred formula for high myopic patients undergoing cataract surgery.

Main Methods:

• A study involving 50 cases with axial length greater than 24 mm was conducted.
• The accuracy of SRK-T and Haigis formulas was assessed by comparing predicted and actual refractive outcomes.
• Statistical analysis was performed to determine significant differences in formula performance.

Main Results:

• The Haigis formula showed a statistically significant lower mean refractive error compared to the SRK-T formula (P=0.005).
• A higher percentage of eyes in the SRK-T group exhibited a mean error greater than 0.5 D.
• 82% of patients achieved good visual acuity (6/6-6/9) by the 6th postoperative week.

Conclusions:

• The Haigis formula is more accurate than the SRK-T formula for IOL power calculation in high axial myopic eyes.
• Utilizing the Haigis formula can help minimize refractive surprises and improve visual outcomes.
• This study underscores the importance of selecting appropriate formulas for specific patient populations.