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Purpose: To evaluate change in retinal layers 18 months after femtosecond laser‐assisted cataract surgery (LCS) and manual cataract surgery (MCS) in a representative age‐related cataract population using artificial intelligence (AI)‐based automated retinal layer segmentation. Methods: This was a prospective, randomized and intraindividual‐controlled study including 60 patients at the Medical University of Vienna, Austria. Bilateral same‐day LCS and MCS were performed in a randomized sequence. To provide insight into the development of cystoid macular oedema (CME), retinal layer thickness was measured pre‐operatively and up to 18 months post‐operatively in the central 1 mm, 3 mm and 6 mm. Results: Fifty‐six patients completed all follow‐up visits. LCS compared to MCS did not impact any of the investigated retinal layers at any follow‐up visit (p > 0.05). For the central 1 mm, a significant increase in total retinal thickness (TRT) was seen after 1 week followed by an elevated plateau thereafter. For the 3 mm and 6 mm, TRT increased only after 3 weeks and 6 weeks and decreased again until 18 months. TRT remained significantly increased compared to pre‐operative thickness (p < 0.001). Visual acuity remained unaffected by the macular thickening and no case of CME was observed. Inner nuclear layer (INL) and outer nuclear layer (ONL) were the main causative layers for the total TRT increase. Photoreceptors (PR) declined 1 week after surgery but regained pre‐operative values 18 months after surgery. Conclusion: Low‐energy femtosecond laser pre‐treatment did not influence thickness of the retinal layers in any topographic zone compared to manual high fluidic phacoemulsification. TRT did not return to pre‐operative values 18 months after surgery. The causative layers for subclinical development of CME were successfully identified. [ABSTRACT FROM AUTHOR]

Purpose: To develop and validate a deep learning model to automatically segment three structures using an anterior segment optical coherence tomography (AS‐OCT): The intraocular lens (IOL), the retrolental space (IOL to the posterior lens capsule) and Berger's space (BS; posterior capsule to the anterior hyaloid membrane). Methods: An artificial intelligence (AI) approach based on a deep learning model to automatically segment the IOL, the retrolental space, and BS in AS‐OCT, was trained using annotations from an experienced clinician. The training, validation and test set consisted of 92 cross‐sectional OCT slices, acquired in 47 visits from 41 eyes. Annotations from a second experienced clinician in the test set were additionally evaluated to conduct an inter‐reader variability analysis. Results: The AI model achieved a Precision/Recall/Dice score of 0.97/0.90/0.93 for IOL, 0.54/0.65/0.55 for retrolental space, and 0.72/0.58/0.59 for BS. For inter‐reader variability, Precision/Recall/Dice values were 0.98/0.98/0.98 for IOL, 0.74/0.59/0.62 for retrolental space, and 0.58/0.57/0.57 for BS. No statistical differences were observed between the automated algorithm and the inter‐reader variability for BS segmentation. Conclusion: The deep learning model allows for fully automatic segmentation of all investigated structures, achieving human‐level performance in BS segmentation. We, therefore, expect promising applications of the algorithm with particular interest in BS in automated big data analysis and real‐time intra‐operative support in ophthalmology, particularly in conjunction with primary posterior capsulotomy in femtosecond laser‐assisted cataract surgery. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study was to compare ultrasound (US) consumption and central macular thickness (CMT) and volume changes with manual and femtosecond laser (FSL)‐assisted cataract nucleus workup. Methods: Sixty patients scheduled for immediate sequential bilateral surgery underwent a prospective randomized intraindividual comparison of nucleus sector fragmentation performed manually in one eye and with low‐energy FSL assistance in the partner eye, followed by high‐fluidics phacoaspiration with a maximum US power of 30%. Ultrasound (US) energy consumption and macular thickness and volume were compared as measured by intraoperative effective phacoemulsification time (EPT) and high‐resolution spectral domain optical coherence tomography pre‐ and 1 week, 3 weeks and 6 weeks postoperatively. Results are presented as means ± SD or medians [min; max]. Results: Fifty‐two patients completed the full follow‐up. For the manual and FSL‐assisted groups, nuclear hardness was almost identical with a mean LOCS III grade of 2.44 ± 1.08 and 2.50 ± 1.00 (p = 0.371). Median EPT was 1.40 [0.2; 8.3] and 1.25 [0.2; 9.4] seconds. Median preoperative CMT was 276.50 [263.25; 289.75] µm and 276.00 [262.00; 290.00] µm. Median postoperative CMT was 278.00 [260.50; 288.00] versus 275.50 [264.00; 290.50] µm at 1 week, 279.50 [266.75; 292.25] versus 280.00 [266.50; 294.50] µm at 3 weeks and 280.50 [268.00, 293.75] versus 279.50 [264.75; 295.25] µm at 6 weeks. Differences in CMT and total macular volume between the groups were not statistically significant at any point in time. Conclusion: Femtosecond laser (FSL) prefragmentation of the nucleus into six sectors did not reduce US energy consumption compared with manual splitting of the nucleus into four quadrants in this particular surgical setting. Sectorial FSL‐prechopping with the low‐energy FSL used had no additional impact on postoperative macular thickness and volume. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to develop a raytracing‐based strategy for calculating corneal power from anterior segment optical coherence tomography data and extracting the individual keratometer index, which converts the corneal front surface radius to corneal power. Methods: A large OCT dataset (10,218 eyes of 8,430 patients) from the Casia 2 (Tomey, Japan) was post‐processed in MATLAB (MathWorks, USA). Radius of curvature, asphericity of the corneal front and back surface, central corneal thickness and pupil size (aperture) were used to trace a bundle of rays through the cornea and derive the best focus plane. Corneal power was calculated with respect to the corneal front vertex plane, and the keratometer index was back‐calculated using corneal power and front surface radius. Keratometer index was analysed in a multivariate linear model. Results: The averaged resulting keratometer index was 1.3317 ± 0.0017 with a median of 1.3317 and range from 1.3233 to 1.3390. In a univariate model, only the front surface asphericity affected the keratometer index. The multivariate model for modelling the keratometer index using all 6 input parameters performed very well (RMS error: 5.54e‐4, R2: 0.90, significance vs. constant model: <0.0001). Conclusions: In the classical calculation, the keratometer index used for converting corneal radius to dioptric power uses several model assumptions. As these assumptions are not generally satisfied, corneal power cannot be calculated from corneal front surface radius alone. Considering all 6 input variables, the linear prediction model performs well and can be used if all input parameters are measured with a tomographer. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the posterior capsule opacification (PCO) and YAG laser capsulotomy (YAG‐LCT) rates with a plate‐haptic acrylic micro‐incision intraocular lens (IOL) and the impact of primary posterior capsulorhexis. Methods: A total of 97 patients scheduled for immediate sequential bilateral cataract surgery underwent a randomized, prospective intraindividual comparison with the ZEISS Asphina 409MV plate‐haptic acrylic IOL with the eyes receiving an additional primary posterior capsulorhexis (PPCR) or not. YAG‐LCT and PCO rates were evaluated at 1 and 3 years. Three‐year PCO rates were calculated with a 3‐scenario method for eyes that underwent YAG‐LCT between 1 and 3 years. Results: A total of 56 patients were seen at 1 year, and 57 at 3 years. For the eyes without and with PPCR, YAG‐LCT rates were 14.3% and 0% at 1 year, and 59.7% and 3.5% at 3 years, respectively. Opacification rates at 1 year were 0.55 ± 0.99 and 0.05 ± 0.21 for the central 2‐mm optic zone. A total of 42 patients completed both the 1‐ and 3‐year follow‐up. Three‐year opacification rates for the group without PPCR were 1.99 ± 2.20, 2.26 ± 2.66 and 3.66 ± 3.61 for the central 2‐mm zone and 2.57 ± 2.07, 3.13 ± 3.03 and 4.09 ± 3.34 for the 4.5‐mm zone for the best, extrapolated and worst‐case scenarios, respectively. Conclusion: The ZEISS Asphina 409MV plate‐haptic acrylic IOL exhibited unusually high YAG‐LCT and PCO rates with standard in‐the‐bag implantation. PPCR was safe and effective in preventing central opacification and the need for YAG laser treatment. [ABSTRACT FROM AUTHOR]

Purpose To compare the incidence and intensity of posterior capsular opacification ( PCO) and neodymium:yttrium-aluminium-garnet (Nd: YAG) capsulotomy rates between two microincision intra-ocular lenses ( IOLs) 3 years after surgery. Methods Sixty-five patients randomly received a Y-60H IOL ( HOYA Surgical Optics, Singapore) in one eye and a Micro AY IOL (Phys IOL, Liège, Belgium) in the contralateral eye during same-day bilateral cataract surgery. Eyes were examined 1 week, 20 months and 3 years after surgery. The amount of PCO (score: 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software ( aqua). Additionally, the Nd: YAG capsulotomy rate was noted. Results Three years postoperatively, the objective PCO score of Y-60H IOLs was 1.9 ± 1.7 compared to PCO score of 1.7 ± 2.2 for the Micro AY IOLs (p = 0.66). Thirty-four percentage of the Y-60H eyes had undergone Nd: YAG capsulotomy, compared to 49% of the Micro AY eyes (p = 0.04). Significantly, more capsular folds were observed in the Y-60H IOL group (p = 0.001). There was no significant difference in best-corrected visual acuity, rhexis/ IOL overlap and anterior capsule opacification 3 years after surgery. Conclusion Both microincision IOLs showed high YAG rates and comparable PCO scores 3 years after surgery. In the light of this unsatisfying PCO performance, the advantage of the present microincision IOLs over conventional IOLs must be questioned. [ABSTRACT FROM AUTHOR]

. Purpose: To compare intraoperative efficiency and postoperative outcomes of cataract surgery with low and high fluidic settings. Methods: In this prospective, randomized, single-blinded study, 114 eyes of 57 patients were operated with low fluidic settings for one eye (group I) and high fluidic settings for the other eye (group II). Efficiency was judged as metred surgery time, effective phacoemulsification time (EPT) and the amount of balanced salt solution used. Visual outcome and endothelial cell count were determined 1 week and 18 months postoperatively. Results: The overall effective phacoemulsification energy was statistically significantly lower (p = 0.003) in group II than in group I. Conquest of the nuclei was achieved with about two-thirds of the energy needed in group I, with 6.59 ± 4.79 effective ultrasound energy compared with 3.99 ± 3.18 (p = 0.001). Overall, about 12% more solution was used in group II than in group I. Median visual acuity was 1.0 for both groups 18 months after surgery. The mean endothelial cell loss was 5.0% in eyes in group I compared with 6.3% in eyes in group II (p > 0.5). Conclusion: Switching from low fluidic settings with a conventional coaxial 20G phacoemulsification tip to higher fluidic settings with a microcoaxial phaco tip statistically significantly decreases EPT. As only marginally more solution was used with the higher aspiration flow, occlusion must be accomplished more often with high than with low fluidics. Aspiration of the quadrants was therefore more efficient with high fluidic settings. The enhanced pump speed did not result in more tissue damage. [ABSTRACT FROM AUTHOR]