Background: IOL power calculation is now a main step in cataract surgeries especially after development of phacoemulsification and intraocular lens (IOL) as the aim of cataract surgery now is no longer media opacity treatment only but also correction of refraction errors. That's why new devices with new techniques as Sirius Scheimpflung tomography which combines both Scheimpflug camera and placido-disk corneal topography (PDCT) and uses ray tracing approach and artificial intelligence (AI) in IOL power calculation was evolved to increase the accuracy of IOL power calculation.
Purpose: Compare the accuracy of predictability of postsurgical refraction of Sirius+ (CSO, Italy) Scheimpflung tomography with Nidek optical biometer AL-scan (Nidek CO., Tokyo, Japan).
Patients and methods: Forty eyes of twenty eight patients were enrolled in this prospective cohort comparative study, which was performed at the Department of Ophthalmology of Ain Shams University Hospitals during the period between April 2023 till December 2023. The patients underwent complete ophthalmological examination and did biometry with both Sirius tomography and Nidek optical biometer, then postsurgical refraction was done using autoref (Shin-Nippon accuref 8001, Japan. Comparison between predicted refraction by Sirius and Nidek with postsurgical refraction was done.
Results: There was a statistically significant difference between the Nidek postsurgical predictive refraction and the postsurgical spherical equivalent (SE) of the studied patients (p< 0.05), while there was a statistically non-significant difference between the Sirius postsurgical predictive refraction and the postsurgical SE (p> 0.05).
Conclusion: Sirius tomography is more accurate in IOL power calculation than Nidek optical biometry.