Toric IOL calculation in keratoconus: novel technique: total Pentacam Ks @ 5mm: Kanellopoulos, MD

Methods: keratoconus is screened in all of our cataract surgery candidates, as we define 1 out of every 15-20 cases! 3 different model interferometries used for axial length, chamber depth & keratometry. Additionally, also with topography, tomography with both Scheimpflug and anterior segment-OCT. Toric IOL was calculated with the: SRK-T, Holliday & Hoffer-Q formulas adjusting the keratometric power and axis from data calculated by a tomography-guided excimer treatment plan @ 5mm optical zone and compared. Results: Holladay 1 calculated the highest IOL spherical power and was preferred in order to avoid hyperopic surprises. Mean values change: UDVA from 20/400 to 20/32, CDVA: 20/50 to 20/24, Refraction in Diopters: sphere: -4.5 to -0.5 and cylinder: 3.5 to 0.75 Conclusions IOL power calculation in keratoconus patients is challenging due to the variability in corneal power and axis measured emmetropia approximation appears superior in our experience with 5mm pentacam Ks and this novel tomography-guided simulation for axis used in toric IOL, along with the Holladay 1 formula (provides the highest sphere IOL) and appears to be safe and very effective. A special note here is the common knowledge that for rigid gas-permeable and scleral lens users, toric IOL option maybe contraindicated