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PURPOSE: To report the results of cataract surgeries in keratoconus patients at 1 and 6 months postoperatively, and to compare the standard intraocular lens (IOL) calculation formulas in this population. METHODS: This is a retrospective study, carried out in 44 eyes of 26 patients known to have keratoconus who underwent cataract surgery at Beirut Eye and ENT Specialist Hospital between 2010 and 2021. The patients were divided into groups based on Dr Jarade updated algorithm. Visual acuities before and after cataract surgery, at 1 and 6 months were recorded, as well as spherical equivalent. The difference between the expected spherical equivalent with each formula was subtracted from the actual resultant refraction, and its absolute value deduced. The means of the values were calculated and the 4 standard formulas (SRK/T, SRK/II, Holladay, and Hoffer Q) were compared. RESULTS: Six eyes had similar topographic and manifest axes (category 1) and underwent toric IOL implantation. Corrected distance visual acuity (CDVA) at 1 and 6 months was 0.2 and 0.1 logMAR, respectively. 26 eyes had mismatching axes and had monofocal IOL placement. CDVA at 1 and 6 months was 0.3. Six eyes required intrastromal corneal ring placement before operating (category 3). CDVA was 0.3 and 0.2 at 1 and 6 months, respectively. Regarding category 4, requiring keratoplasty and cataract extraction, CDVA was 0.4 at both follow‑ups. No statistically significant difference was found between the different formulas. CONCLUSION: Categorization of keratoconus patients gave favorable results after cataract surgery. No superior IOL formula was found. [ABSTRACT FROM AUTHOR]

PURPOSE: Our article aims to assess the accuracy of modified and commonly used formulas of intraocular lens (IOL) power calculation after excimer laser corneal refractive surgery. METHODS: This is a retrospective study, with data retrieved for 50 eyes of 32 patients who underwent uncomplicated cataract surgery after excimer laser corneal refractive surgery. The expected spherical equivalent was calculated using the American Society of Cataract and Refractive Surgeons (ASCRS) IOL power calculator for Shammas and Barrett True‑K, using three‑fourth generation formulas (Haigis‑L, Barrett True‑K no history, and Holladay 2), and using three‑third generation formulas (SRKT, Holladay 1, and Hoffer Q) with single k, as a reference, and adjusting these formulas by calculating the keratometry readings by two methods (Jarade’s index and formula). The mean refractive error and mean absolute refractive error (MARE) were calculated at the 1 postoperative month. RESULTS: When all data was available (eight eyes), 13 formulas were compared. Holladay 1 as modified by Jarade’s index and formula, and Hoffer Q as modified by Jarade’s formula resulted in MARE <0.75D (P < 0.05). In the group of 25 eyes with only ablation available, the formulas with MARE <0.75D were Haigis L, Barrett TK (from ASCRS), Hoffer Q, and the three conventional formulas in Jarade’s index (P < 0.001). In the group of 17 eyes with no available prerefractive data, only Haigis‑L and Barret TK (no history) had a MARE <0.75 D. CONCLUSION: The use of Hoffer Q or Holladay 1, when prerefractive data are available, gives reliable results with Jarade’s index. [ABSTRACT FROM AUTHOR]