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Purpose: To use a combination of partial least squares regression and a machine learning approach to predict intraocular lens (IOL) tilt using preoperative biometry data., Setting: Kepler University Clinic Linz, Linz, Austria., Design: Prospective single-center study., Methods: Optical coherence tomography, autorefraction, and subjective refraction were performed at baseline and 8 weeks after cataract surgery. In analysis I, only 1 eye per patient was included and a tilt prediction model was generated. In analysis II, a pairwise comparison between right and left eyes was performed., Results: In analysis I, 50 eyes of 50 patients were analyzed. Difference in amount, orientation, and vector from preoperative to postoperative lens tilt was -0.13 degrees, 2.14 degrees, and 1.20 degrees, respectively. A high predictive power (variable importance for projection [VIP]) for postoperative tilt prediction was found for preoperative tilt (VIP = 2.2), pupil decentration (VIP = 1.5), lens thickness (VIP = 1.1), axial eye length (VIP = 0.9), and preoperative lens decentration (VIP = 0.8). These variables were applied to a machine learning algorithm resulting in an out of bag score of 0.92 degrees. In analysis II, 76 eyes of 38 patients were included. The difference of preoperative to postoperative IOL tilt of right and left eyes of the same individual was statistically relevant., Conclusions: Postoperative IOL tilt showed excellent predictability using preoperative biometry data and a combination of partial least squares regression and a machine learning algorithm. Preoperative lens tilt, pupil decentration, lens thickness, axial eye length, and preoperative lens decentration were found to be the most relevant parameters for this prediction model., (Copyright © 2024 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To determine (1) if measurements of surgically induced astigmatism (SIA) as measured by keratometry (K) and total keratometry (TK) differ (2) if SIA affects the magnitude and/or meridian of keratometric astigmatism (3) if SIA evolves over time., Setting: Tertiary care center., Design: Retrospective data analysis., Methods: A swept-source optical coherence tomography biometry dataset (IOLMaster700) consisting of 498 eyes (327 patients) from a tertiary care center was analyzed. For all eyes preoperative and postoperative biometric measurements at 1-month, 3-month, and 6-months postoperative visits were considered for vector analysis of SIA K and SIA TK ., Results: Centroids in right and left eyes were 0.26 diopters (D) @5 degrees/0.31 D @1 degree for SIA K and 0.27 D @4 degrees/0.34 D @1 degree for SIA TK . Centroids for difference vectors K-TK in right and left eyes were 0.02 D @ 176 degrees/0.03 D @6 degrees. The mean SIA magnitudes in right and left eyes were 0.48 ± 0.41 D and 0.50 ± 0.37 D for SIA K and 0.53 ± 0.42 D and 0.54 ± 0.40 D for SIA TK . In eyes with ATR astigmatism, an increase in postoperative astigmatism magnitude was more common than a decrease. More than 30% of eyes showed changes in the meridian of more than 15 degrees., Conclusions: Overall, we observed differences in K- and TK-derived SIA, and changes in SIA magnitude over time. For postsurgical interventions, postoperative astigmatism meridian values should be measured to base treatments. Astigmatism magnitude showed a tendency to decrease for steep-meridian incisions and to increase in flat-meridian incisions., (Copyright © 2023 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To evaluate the accuracy of phakic intraocular lens (pIOL) power calculation in a middle European patient cohort., Setting: EyeLaser Clinic, Linz, Austria., Design: Single-center single-surgeon retrospective consecutive case series., Methods: Patients were included after uneventful pIOL surgery implanting 91 nontoric and toric Visian implantable collamer lens model V4c. Online Calculation and Ordering System (OCOS) software, JPhakic software, Olsen-Feingold formula, Holladay formula, and Linz-Homburg-Castrop (LHC) formula were compared. When possible, lens constants were optimized for the patient cohort. Data of single eye per patient were included. Outcome measures were mean absolute prediction error, median absolute prediction error, mean prediction error with SD, and median prediction error, as well as the percentage of eyes with an absolute prediction error within limits of 0.25 diopters (D), 0.5 D, 0.75 D, and 1.0 D., Results: 91 eyes of 91 patients were assessed. After application of the Cochran Q test, the Olsen-Feingold formula achieved a significantly lower percentage of eyes within an absolute prediction error of 1.0 D than all other methods., Conclusions: In the patient cohort, OCOS software, JPhakic software, and Holladay and LHC formulas showed equal results and can be cross-checked. The LHC formula was not published before. A ready-to-use Excel sheet is available as an addendum., (Copyright © 2022 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To compare the lens tilt after apex-centered capsulotomy with standard pupil-centered capsulotomy., Setting: Clinical practice., Design: Prospective, randomized, investigator-masked trial., Methods: This prospective, randomized, investigator masked study included 40 patients with age-related cataract scheduled for femtosecond laser-assisted cataract surgery (FLACS) in both eyes. The main outcome was the tilt of the intraocular lens (IOL), measured with the IOLMaster 700., Results: The study enrolled 80 eyes of 40 patients. The mean distance from the center of the apex-centered capsulotomy to the pupil-centered capsulotomy was 175.8 ± 97.2 μm. The amount of IOL tilt was not significantly reduced with the new technique (P > .05). Tilt orientation was more stable in eyes treated with apex-centered capsulotomy., Conclusions: Centration of the capsulotomy on the lens apex in FLACS does not influence the amount of IOL tilt but the orientation stability. The clinical importance of this finding has to be further elucidated., (Copyright © 2021 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To study the intraocular pressure (IOP) variation during vacuum and docking of femtosecond laser application., Setting: Department for Ophthalmology, Kepler University Hospital, Johannes Kepler University Linz, Austria., Design: Experimental study., Methods: Intracameral intraocular pressure (IOP) was monitored in 30 porcine ex vivo models using a dual femtosecond laser platform (VICTUS). Five different baseline IOP levels (10 to 30 mm Hg) were assessed during fluid-filled (liquid) docking, full-contact (applanating) docking, and vacuum application without docking., Results: Raising the baseline intracameral IOP from 10 to 30 mm Hg increased the IOP from 27.55 mm Hg ± 5.93 (SD) to 56.85 ± 6.10 mm Hg in the fluid-filled docking group, and from 60.91 ± 8.41 mm Hg to 90.11 ± 6.64 mm Hg in the full-contact docking group. The full-contact docking procedure per se (excluding vacuum effect) increased the IOP by 61.7% (+36.58 ± 5.84 mm Hg). In contrast, fluid-filled docking (excluding vacuum effect) raised the IOP by only 3.1% (+0.72 ± 2.71 mm Hg). Each 5 mm Hg reduction of baseline IOP resulted in a mean IOP reduction of 7.33 ± 3.05 mm Hg in the fluid-filled group, and 7.30 ± 6.88 mm Hg in the full-contact docking group (P < .001). Decreasing baseline intracameral IOP from 15 to 10 mm Hg resulted in the highest IOP reduction between all subgroups (P < .01)., Conclusions: Baseline IOP, docking procedures, and vacuum influenced IOP during femtosecond laser application in a synergistic manner. Lowering the baseline intracameral IOP resulted in a significantly lower IOP during fluid-filled docking for cataract surgery and full-contact docking for refractive surgery. Full-contact (applanating) docking resulted in a significantly higher IOP elevation compared with similar IOP values found during fluid-filled (liquid) docking and the application of the suction ring alone without docking., (Copyright © 2019 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To prospectively characterize the stromal thickness changes during the first year after myopic small-incision lenticule extraction using spectral-domain optical coherence tomography (SD-OCT)., Setting: Department of Ophthalmology, Kepler University Hospital, Linz, Austria., Design: Prospective case series., Methods: This study evaluated eyes that had small-incision lenticule extraction to treat myopia or myopic astigmatism. A high-resolution SD-OCT system (RS 3000 Advance) in conjunction with a custom image-segmentation algorithm was applied to directly measure stromal thickness within the central 5.0 mm corneal zone. Measurements were obtained preoperatively and postoperatively at 1 day, 1 week, 6 weeks, 3 months, 6 months, and 1 year., Results: The study enrolled 42 eyes of 21 patients. The mean surgical refractive correction was -4.94 diopters ± 1.75 (SD). Postoperatively, the stromal thickness showed a significant decrease during the first 6 weeks, which amounted to a mean of 10.4 ± 6.3 μm at the apex (P < .001). Subsequently, the central stroma thickened by a mean of 8.8 ± 5.9 μm up until the 1-year follow-up (P < .001). One year postoperatively, the mean observed central stromal thickness reduction was 18.7 ± 5.7 μm smaller than the planned lenticule thickness. This difference was smallest 6 weeks postoperatively (mean 9.8 ± 7.8 μm)., Conclusions: Significant anatomic changes in the corneal stroma were detected during the first year after small-incision lenticule extraction. The achieved lenticule thickness was systematically lower than planned, and the mismatch was more pronounced with higher lenticule thickness. Refractive outcomes did not appear to be influenced by lenticule thickness accuracy., (Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the safety and efficacy between femtosecond laser-assisted cataract surgery using the Victus laser system and conventional cataract surgery., Setting: Department of Ophthalmology, Kepler University Hospital, Linz, Austria., Design: Prospective randomized case series., Methods: Both eyes of patients with age-related cataract were randomized to conventional cataract surgery or femtosecond laser-assisted cataract surgery, both with intraocular lens (IOL) implantation. Postoperative follow-up was at 1 day, 1 week, 1 month, 3 months, and 6 months and comprised corrected distance visual acuity, endothelial cell density (ECD), central corneal thickness (CCT), and central retinal thickness. The main outcomes were intraoperative and postoperative complications and the effective phacoemulsification time (EPT). Intraocular lens and capsulotomy centration were evaluated using retroillumination slitlamp photography., Results: The study enrolled 50 patients. No intraoperative complications occurred in either group. The ECD, CCT, and central retinal thickness were similar between the groups at all follow-up examinations (P > .05). The EPT was not statistically significantly different between the groups (P = .22). The IOL centration was similar between the groups (P = .93)., Conclusion: Femtosecond laser-assisted and conventional cataract surgery using the mentioned system were equally safe and effective., (Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess whether a temporal limbal-corneal incision approach for phacoemulsification cataract surgery induces a gradient in corneal thickening along the horizontal meridian., Setting: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria., Methods: Corneal thickness in 21 eyes of 21 patients was measured preoperatively as well as 1 day, 1 week, and 1 and 3 months after phacoemulsification through a temporal limbal-corneal incision. Measurements were performed using partial coherence interferometry (PCI) with a commercial instrument, the ACMaster (Carl Zeiss Meditec, Jena). Measurements were taken along the horizontal meridian centrally along the visual axis at 1.5 mm, 3.0 mm, and 4.5 mm eccentricity., Results: Preoperatively, there were slight nasal-temporal differences in corneal thickness at all eccentricities. The mean thickness was 522 microm +/- 34 (SD) at 1.5 mm nasally and 513 +/- 36 microm at 1.5 mm temporally (P<.01). On day 1, there was a significant mean increase in corneal thickness (38 +/- 43 microm) along all locations. The thickening was slightly more pronounced in the periphery than in the center, a difference not reaching statistical significance. At 1 week, corneal thickness returned almost to baseline at all locations except for 3.0 mm temporally, where it was slightly, but not significantly, thicker (mean 8 +/- 14 mum). At 1 month, corneal thickness at the 3.0 mm temporal location returned to baseline., Conclusions: A nasal-temporal difference in corneal thickness was found preoperatively in all patients. Phacoemulsification through a temporal limbal-corneal incision caused an increase in corneal thickness along the horizontal meridian 1 day after surgery. The prolonged corneal thickening at 3.0 mm eccentricity temporally could be a result of the proximity to the incision site.

Purpose: To evaluate the long-term effects of anterior capsule polishing on regeneratory posterior capsule opacification (PCO), anterior capsule opacification (ACO), and fibrotic PCO with a silicone intraocular lens (IOL) with sharp optic edges., Setting: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria., Methods: This prospective bilateral randomized patient- and examiner-masked clinical trial comprised 130 eyes of 65 patients with bilateral age-related cataract. All eyes had implantation of a 3-piece silicone IOL with a truncated, sharp-edged optic (CeeOn Edge 911A, Advanced Medical Optics). In 1 eye, the anterior capsule was extensively polished using an aspiration curette after phacoemulsification and cortex aspiration. Regenerative PCO was quantified objectively, while ACO and fibrotic PCO were graded subjectively 1, 2, 3, and 5 years postoperatively., Results: The mean ACO score was significantly lower in the eyes in which the anterior capsule had been polished (1 year, P<.02; 2 years, P<.03; 3 years, P<.01; 5 years, P<.01). The mean difference in regeneratory PCO and fibrotic PCO scores between the 2 groups was not statistically significant., Conclusions: Three years after cataract surgery, eyes in which the anterior capsule had been polished had significantly less ACO. However, polishing did not lower PCO intensity when a sharp-edged CeeOn 911A IOL was implanted in the bag. Although results indicate that anterior capsule polishing may enhance the development of regeneratory PCO, this trend did not reach statistical significance.