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Purpose: To evaluate the accuracy of several intraocular lens (IOL) formulas for patients with endothelial dystrophy (ED) without edema treated with cataract surgery alone., Setting: One academic, tertiary referral center., Design: Comparative retrospective cohort study., Methods: We assessed the predicted refractive results of ED patients who underwent cataract surgery and compared them to a matched control group. The accuracy of five different IOL formulas Haigis, Holladay 1, Barrett Universal II, SRK/T and Kane was evaluated and compared between the groups. The standard deviations of the prediction error of all formulas were compared., Results: The study included 221 eyes. Fifty (23%) eyes of patients with ED and 171 (77%) control eyes. There was no significant difference between the two groups in clinical and demographical characteristics (P>0.05). The postoperative spherical equivalent was -0.37 D in the ED group and -0.30 D in the control group (P=0.8). Overall, both groups had a comparable standard deviation of the prediction error (PE) and absolute PE (APE) in all formulas (p>0.05). In the ED group, APE was 0.34 D for Haigis, 0.32 D for Holladay1, 0.32 D for Barrett Universal II, 0.38 D for SRK/T and 0.32 D for Kane formulas. No statistically significant difference between formulas was found., Conclusion: The prediction accuracy of IOL power calculation in patients with ED was found comparable both between formulas and in comparison with healthy controls. This suggests that in patients with guttate without edema the IOL power calculations are as effective and accurate as in healthy eyes., (Copyright © 2024 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To compare corrected distance visual acuity (CDVA) outcomes of hyperopic laser in situ keratomileusis (LASIK) with a postoperative corneal steepness above vs below 49 diopters (D)., Setting: Care-Vision Laser Centers, Tel-Aviv, Israel., Design: Retrospective study., Methods: This study included consecutive patients who underwent hyperopic LASIK between January 2013 and December 2019. Hyperopic patients were divided into 2 groups based on postoperative corneal steepness with steep corneas defined >49.0 D and the control group ≤49.0 D. Adjustments were performed to account for differences in baseline and intraoperative parameters., Results: Overall, 1703 eyes of 1703 patients were included. Mean age was 48.3 ± 10.0 years, and 45.3% were male. Preoperatively, the steep group (2.4%, n = 41/1703) had steeper mean (44.6 D vs 43.1 D, P < .001) and steep (45.1 D vs 43.5 D, P < .001) keratometry, worse logMAR CDVA (0.07 vs 0.04, P = .02), and higher sphere (4.9 D vs 2.9 D, P < .001). Intraoperatively, they had a higher spherical treatment (4.6 D vs 2.8 D, P < .001). After hyperopic LASIK, the steep group had worse logMAR CDVA (0.10 vs 0.06, P = .01). However, after accounting for differences in baseline and spherical treatment, no significant differences were found in postoperative logMAR CDVA (0.06 vs 0.06, P = .99). The factors that remained associated with worse postoperative CDVA were higher spherical treatment (0.01 logMAR per 1 D, P < .001) and preoperative CDVA (0.60 logMAR per 1.00 logMAR, P < .001)., Conclusions: Postoperative corneal steepness greater than 49 D is not associated with worse visual outcomes after hyperopic LASIK. However, lower preoperative visual potential and higher spherical treatment applied are associated with worse outcomes. The 49 D cutoff should be revisited., (Copyright © 2024 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To measure the time to fragment removal and number of chatter events using various combinations of micropulse on times and off times (measured in milliseconds) of longitudinal ultrasound (US) using a venturi-based phacoemulsification system., Setting: John A. Moran Eye Center, University of Utah, Salt Lake City, USA., Design: Experimental study., Methods: Pig lenses were hardened with formalin and cut into 2.0 mm cubes. The time to fragment removal (efficiency) and frequency of fragments bouncing off the tip (chatter) were measured with the venturi-based system. Micropulse longitudinal US was tested. Parameters were combinations of 5, 6, and 7 milliseconds on, with 5, 6, and 7 milliseconds off. Twenty runs each of 9 combinations were completed., Results: There was a statistically significant difference between on/off duty cycle combinations. The 6 on/7 off group had higher efficiency than the 5 on/6 off and 7 on/7 off groups. Six on/5 off was more efficient than 5 on/6 off. When data were pooled and on times alone were used, 6 milliseconds on time was more efficient than 5 or 7 milliseconds. No efficiency differences in off times were found. No significant chatter differences were observed., Conclusions: Using micropulse longitudinal US in venturi vacuum mode, 6 milliseconds on was the most efficient on time. Five, 6, and 7 milliseconds off times had similar efficiency. These data suggest that the most efficient setting with lowest US energy use is 6 milliseconds on and 7 milliseconds off., (Copyright © 2019. Published by Elsevier Inc.)