Refractive Outcomes Research Articles

Comparison of keratometry and total corneal power, as measured by an SS-OCT-based optical biometer, for intraocular lens power calculation in Asian eyes.

To investigate whether standard keratometry (K) or total corneal power (TCP) leads to more accurate refractive outcomes for intraocular lens (IOL) power calculation. Public hospital. Retrospective evaluation of a diagnostic test instrument. Preoperatively, all patients underwent optical biometry with Anterion, a swept-source optical coherence tomography device providing both K and TCP. The same IOL model was implanted in all cases. The whole sample was divided into a training dataset, used to optimize the formula constants, and a testing dataset, used to investigate the spherical equivalent prediction error (SEQ-PE) of 8 IOL power formulas. Trueness, precision, and accuracy were evaluated by means of the robust 2-sample t test. Cochran Q test was performed to assess whether the percentage of eyes with an SEQ-PE within each threshold was significantly different; in such an event, the McNemar test was then applied. Both the training and testing datasets included 317 eyes. No significant differences were detected for trueness because of constant optimization. Precision and accuracy were better when K was entered, although a statistically significant difference was observed only with the EVO (precision: P = .02 and accuracy: P = .03) and Haigis ( P < .01 for both precision and accuracy) formulas. No significant differences were observed for the percentage of eyes with an absolute SEQ-PE within any threshold. With most formulas, IOL power calculation is not more accurate when TCP is used instead of K.

Comparative study of transepithelial versus alcohol-assisted photorefractive keratectomy

Aim The aim of this study was to compare the clinical, refractive, and visual outcome of transepithelial photorefractive keratectomy (T-PRK) to the alcohol-assisted photorefractive keratectomy (AA-PRK). Patients and methods This is a prospective randomized controlled trial that included 60 myopic patients (120 eyes). They were randomized into two groups, 60 eyes each: group I (AA-PRK) and group II (T-PRK). The operation was performed in both groups by the same Excimer laser machine (EX 500 Excimer laser WaveLight). In the alcohol-assisted group, the corneal epithelium was removed by 20% ethyl alcohol followed by Excimer laser to correct the amount of ametropia. In the T-PRK group, the Streamlight PRK software (WaveLight EX 500) was used, which incorporated Excimer laser stromal ablation and epithelial removal in a single step. After completion of each procedure in both groups, mitomycin C with a concentration of 0.02% was used for 30 s, followed by copious irrigation with a cold balanced salt solution. A soft bandage contact lens was applied until epithelial healing was complete for 5 days and changed after 48 h. The patients were evaluated postoperatively on the first, third, and fifth day, then after 1 week, 1 month, and 3 months. On the first visit, uncorrected visual acuity (UCVA), epithelial healing, and postoperative pain were evaluated. At 1-week and 1-month follow-up visits, UCVA, best-corrected visual acuity (BCVA), manifest refraction spherical equivalent (MRSE), Schirmer’s I, and tear break-up time (TBUT) tests were evaluated. The corneal haze was evaluated using a slit lamp biomicroscope and subjectively graded. At the 3-month follow-up, UCVA, BCVA, MRSE, Schirmer’s I test, TBUT test, and root mean square (RMS) assessment for total higher-order aberration were evaluated. Results There was an insignificant difference between the studied groups regarding all baseline ophthalmological assessments including UCVA, BCVA, MRSE, central corneal thickness, RMS, TBUT, and Schirmer’s test (P=0.839, 0.057, 0.187, 0.537, 0.219, 0.013, and 0.151, respectively). After 3 months, the median UCVA was the same in both groups (1.0), while the MRSE did not differ significantly between the two groups (P=0.126), with a median (interquartile range) of −0.25 D (−0.75 to 0.25 D) in the AA-PRK group compared to −0.25 D (−0.50 to 0.3125 D) in the T-PRK group. The healing duration was significantly shorter in the T-PRK group (median=3.0 days) than in the AA-PRK group (5.0 days, P&lt;0.001). The median postoperative pain was also significantly higher in the AA-PRK group (4.0) than in the T-PRK group (3.0, P&lt;0.001). The RMS was significantly lower in the T-PRK group (median=0.35) than in the AA-PRK group (median=0.65, P&lt;0.001). The corneal haze did not differ significantly between the two groups after 1 month (P=0.783). After 3 months, the Schirmer’s test was significantly lower in the AA-PRK group (median=18.0 mm) than in the T-PRK group (19.0 mm, P&lt;0.001), while the TBUT test showed no significant difference (P=0.055). Conclusion The T-PRK technique provided a faster visual recovery with a better refractive outcome, faster healing response, less pain score, and less dryness than the AA-PRK.

Visual Outcomes and Patient Satisfaction After Bilateral Refractive Lens Exchange With a Trifocal Intraocular Lens in 5,226 Patients With Presbyopia.

To assess visual and refractive outcomes and visual function after bilateral RayOne Trifocal toric and nontoric intraocular lens (IOL) (Rayner) implantation in patients with presbyopia. Charts of patients with presbyopia who underwent refractive lens exchange with bilateral implantation of the RayOne Trifocal IOL (toric and non-toric) were retrospectively reviewed. Visual and refractive outcomes were evaluated at 3 months. Patient satisfaction, spectacle independence, and visual disturbance profile were assessed by questionnaires. A total of 5,226 patients were assigned to one of two groups: 1,010 patients had toric IOL implantation (toric group) and 4,216 patients received the non-toric model (non-toric group). Mean ± standard deviation visual acuity at 3 months for the toric group was binocular uncorrected distance visual acuity (UDVA) of 0.07 ± 0.11 logMAR, monocular corrected distance visual acuity (CDVA) of 0.05 ± 0.07 logMAR, binocular uncorrected near visual acuity (UNVA) at 40 cm of 0.10 ± 0.09 logMAR, binocular uncorrected intermediate visual acuity (UIVA) at 40 cm of 0.13 ± 0.12 logMAR, postoperative spherical equivalent (SE) of -0.21 ± 0.47 diopters (D), and cylinder of -0.34 ± 0.40 D. The non-toric group had binocular UDVA of 0.04 ± 0.08 logMAR, monocular CDVA of 0.05 ± 0.07 logMAR, binocular UNVA of 0.10 ± 0.08 logMAR, binocular UIVA of 0.13 ± 0.11 logMAR, SE of -0.08 ± 0.38 D, and cylinder of -0.28 ± 0.34 D. No statistically significant differences were found in achieving spectacle independence and there were high levels of satisfaction in both groups. In this retrospective analysis with more than 5,000 patients, both the toric and non-toric RayOne Trifocal IOL models provided good visual performance at all distances, resulting in excellent levels of spectacle independence and patient satisfaction. [J Refract Surg. 2024;40(7):e468-e479.].

Refractive Outcomes Following Combined Cataract and Microinvasive Glaucoma Surgery

To compare refractive outcomes in eyes undergoing cataract extraction (CE) alone, CE with goniotomy (CE/goniotomy), and CE with Schlemm's canal stent (CE/SCS) insertion. Retrospective cohort study. Eyes from the Bascom Palmer Glaucoma Repository undergoing CE/goniotomy, CE/SCS insertion, or uncomplicated CE alone between July 2014 and February 2022 were identified. Refraction data were analyzed at post-operative month (POM) 1 and 6 with Kruskal-Wallis and Dunn's tests. Anisometropia was defined as a spherical equivalent (SE) difference of ≥2D. The primary outcome was mean refraction at POM1 and POM6 across the three surgical groups. Secondary outcomes were comparisons of refraction and visual acuity among different goniotomy and SCS devices, as well as incidence of anisometropia. A total of 8,360 eyes (150 CE/goniotomy, 395 CE/SCS, and 7,815 CE alone) from 6,059 patients were analyzed. At POM1, mean SE in the CE/goniotomy, CE/SCS, and CE alone groups was -0.36±0.91D, -0.31±0.85D, and -0.39±0.88D respectively (p=0.019). Mean logMAR VA was 0.10±0.20, 0.08±0.19, and 0.14±0.26 respectively (p=0.002, CE/SCS vs. CE alone). No statistically significant differences were noted at POM6. Anisometropia occurred at POM1 in 2 patients (13.3%) in the CE/goniotomy-CE group, 1 patient (3.2%) in the CE/SCS-CE group, and 184 patients (4.9%) in the CE-CE group (p=0.217). At POM6, mean SEs were -0.38±0.97D (CE/goniotomy), -0.35±0.81D (CE/SCS), and -0.40±0.91D (CE alone; p=0.473). No significant differences in overall refractive outcomes were observed with different SCS or goniotomy devices. Among primary open-angle glaucoma (POAG) / normal-tension glaucoma (NTG) eyes, mean SE at POM1 was -0.36±0.73D (CE/goniotomy), -0.24±0.84D (CE/SCS), and -0.45±0.81D (CE alone; p<0.001). Concurrent SCS insertion or goniotomy with CE was associated with some statistically significant differences in postoperative refraction and visual acuity, although these small magnitude differences were unlikely to be clinically meaningful.

A simultaneous post-LASIK sequential bilateral implantation of multifocal IOLs aimed at refraction correction. A clinical case

The article presents a clinical example of intraocular presbyopia correction in a patient who previously underwent laser vision correction by LASIK for mild myopia. Before the surgery, the distance VA mono- and binocular was 1.0, ADD for reading distance 40 cm +2.0 D, objective refraction sph +0.5 D cyl -0.25 D ax 980, left eye sph +0.75 D cyl -0.25 D ax 660. The patient was given a simultaneous bilateral refractive lens exchange with an implantation of a trifocal aspheric intraocular lens in the right eye and a trifocal toric aspheric intraocular lens in the left eye. We used the following IOL calculation formulas: ASCRS mean IOL power, Shammas formula, Barrett true K formula, Masket formula, Modified Masket formula, Haigis-L formula. 1 week postop: UDVA OU = 1.0, UNVA 40 cm = 1.0, UVA 70 cm = 0.7. The objective refraction OD was sph +0.0, D cyl -0.75 D ax 163, OS sph +0.25 D, cyl -0.0 D. The compliance with the modified algorithms of pre-and intraoperative behavior of the operating team, thorough preparation of the patient, careful calculation of the IOL allowed us to obtain the predictive refractive result with a high level of visual satisfaction and absence of undesirable postoperative phenomena. The patient underwent the examination with Salzburg reading desk before and after the surgery, to confirm the excellent functional results of the treatment. Despite the fact that simultaneous same day IOL implantation in both eyes, especially in eyes with previously operated corneas, is still disputable, the above case confirms that with modern equipment, precise multi formula calculation, and ample experience help achieve excellent functional and refractive results.

Outcomes of Corneal Compound Hyperopic Astigmatism With Presbyopia by Zeiss PRESBYOND Laser Blended Vision LASIK Using Default Custom Refractive Software Master Target Refractions for Reduced Anisometropia.

To evaluate the effectiveness, safety, and stability of a modified PRESBYOND Laser Blended Vision protocol (Carl Zeiss Meditec AG) for correcting hyperopic astigmatism and presbyopia, using Custom Refractive Software Master (CRSM) targeting over a 6-month period. A total of 636 eyes of 318 patients with a mean age of 51.05 ± 4.71 years (range: 40 to 60 years) met the inclusion and exclusion criteria. All patients completed a 6-month follow-up. CRSM software was used to generate ablation profiles for the MEL90 excimer laser (Carl Zeiss Meditec AG). The target refraction was emmetropic for the dominant eyes and between -0.75 and -1.12 diopters (D) for the near eyes. Visual and refractive results were studied separately by the dominant and non-dominant eyes. The mean attempt to correct for spherical equivalent refraction was +2.17 ± 1.16 D (range: -1.00 to +5.37 D). The mean attempted cylinder was -0.60 ± 0.75 D (range: -4.00 to 0.00 D). All eyes monocularly achieved uncorrected distance visual acuity (UDVA) of 20/25 or better after refractive treatment and 88% achieved 20/20. Binocularly all eyes achieved UDVA of 20/25 or better and 96.54% achieved 20/20. Ninety-eight percent of the patients maintained their corrected distance visual acuity before surgery and UDVA 6 months after surgery. This hyperopic micro-anisometropia protocol with PRESBYOND Laser Blended Vision was an effective, safe, and well-tolerated refractive treatment. It was an effective procedure with excellent results for UDVA and uncorrected near visual acuity and demonstrates that binocular summation exists. [ J Refract Surg. 2024;40(7):e480-e489.].

Evaluation and Refractive Results Comparison of MIOL-­SOFT-­2­-13 IOL Implantation with Foreign Models

Purpose. Evaluation and refractive results comparison of MIOL-­SOFT-­2­-13 (Reper­NN, Russia) IOL implantation with foreign models. Material and methods. The study included 816 patients (816 eyes) who underwent phacoemulsification (PE) with IOL implantation, divided into four groups depending on IOL model: MIOL­-SOFT-2-­13 (Reper­-NN, Russia) (n = 199); SA60AT (Alcon, USA) (n = 237); Adapt AO (Bausch&amp;Lomb, USA) (n = 179); Acryfold 601 (Appasamy Associates, India) (n = 201). All patients underwent optical biometry using IOL­-Master 500 (Carl Zeiss, Germany). A month after PE spherical equivalent of refraction was assessed by Topcon­8800 (Japan). Mean calculation error (ME) and mean absolute error (MAE) were used as a IOL calculation accuracy criterion. Results. Zeroing of ME allowed to determine real a­constant of MIOL-­SOFT­-2-­13 (119.83 instead of 118.4 declared by the manufacturer). MAE in the groups was: 0.39 ± 0.27, 0.33 ± 0.35, 0.38 ± 0.31 and 0.38 ± 0.30 D, respectively (p = 0.068). All IOLs demonstrated hitting the target refraction within ±1.00 D in more than 95 % of cases. Conclusion. MIOL­-SOFT­-2­-13 has comparable refractive results with other monofocal IOLs used in national medical insurance system. MIOL­-SOFT-­2­-13 achieves target refraction within ±1.00 D in 98 % of cases.To obtain optimal refractive results, an optimized a­constant of 118.83 is required.

The Efficiency, Predictability, and Safety of First-Generation (Visumax 500) and Second-Generation (Visumax 800) Keratorefractive Lenticule Extraction Surgeries: Real-World Experiences.

We aimed to evaluate the postoperative visual and refractive outcomes between the first- and second-generation keratorefractive lenticule extraction (KLEx) surgeries. A retrospective cohort study was conducted and patients who had received first- and second-generation KLEx surgeries were enrolled. A total of 80 and 80 eyes were categorized into the first and second KLEx groups after exclusion, respectively. The primary outcomes were the postoperative uncorrected distance visual acuity (UDVA), spherical equivalent (SE), and safety indexes. An independent t-test and generalized estimate equation were implemented to compare the primary outcomes between the two groups. After the KLEx surgery, the UDVA showed no significant difference between the two groups throughout the study period (all p > 0.05), and the postoperative SE and safety index were also statistically identical between the two groups during the follow-up interval (all p > 0.05). There was a similar trend of visual recovery between the two groups (aOR: 0.967; 95% CI: 0.892-1.143; p = 0.844), while the amplitude of the SE change was significantly lower in the second KLEx group (aOR: 0.760; 95% CI: 0.615-0.837; p = 0.005). Nine and two unintended initial dissection of the posterior plane (UIDPP) occurred intraoperatively in the first and second KLEx groups, respectively, and the second group showed a lower risk of UIDPP (p = 0.032). In conclusion, the efficiency, predictability, and safety are similar between first- and second-generation KLEx surgeries.

Accuracy of intra ocular lens calculation formulae in patients with pseudoexfoliation syndrome

BackgroundThe purpose of this study was to investigate the visual and refractive outcomes in patients with pseudoexfoliation (PXF) undergoing routine cataract surgery and to compare the accuracy of intraocular lens (IOL) power calculation formulae.MethodsRetrospective case-series study from Shamir medical center, a public hospital, Israel. Medical records of patients who underwent routine cataract surgery between January 2019 and August 2021 were investigated. Postoperative visual acuity and manifest refraction were examined. The error in predicted refraction and IOL power calculation accuracy within a range of ± 0.50 to ± 1.00 diopters were compared between different IOL calculating formulae.Results151 eyes of 151 patients ages 73.9 ± 7.1 years were included in this study- 58 eyes in the PXF group and 93 eyes in the control group. The mean absolute error (MAE) for the BUII formula was 0.63D ± 0.87 for the PXF group and 0.36D ± 0.48 for the control group (p < 0.05). The MAE for the Hill-RBF 3.0 formula was 0.61D ± 0.84 for the PXF group and 0.42D ± 0.55 for the control group (p = 0.05). There were significant differences in MAE and MedAE between PXF group and control group measures (p < 0.05). In the PXF group there were no significant differences between the different formulae.ConclusionsThere were significant differences in accuracy of IOL power calculations in all formulae between PXF group and control group measures. PXF patients show hyperopic shift from predicted refraction. Barret universal II formula had the highest proportion of eyes with absolute error in prediction below or equal to 0.50 D in both PXF and control groups.

Comparison of the effectiveness of different corneal curvature measurement methods for IOL implantation in traumatic aphakic eyes with corneal injury.

To assess the refractive outcomes of secondary intraocular lenses (IOL) in patients with traumatic aphakic eyes with corneal penetrating injury and compare different corneal curvature measurement methods. Patients with unilateral penetrating eye injuries underwent corneal wound repair and cataract extraction, followed by secondary IOL implantation. Corneal curvature measurements were taken on the contralateral healthy eye (Group A), from the affected eye before removing corneal sutures (Group B), or after suture removal (Group C). The refractive outcomes were compared among the three groups. The study included 261 eyes. The Mean Absolute Error (MAE) in Group C (0.99 ± 0.85 D) was significantly smaller than that in Group A (1.87 ± 1.71 D) and Group B (1.37 ± 1.20 D) (both P < 0.001). Moreover, the percentage of eyes with IOL prediction errors within ± 0.50 D in Group C (40%) was higher than that in group A (21.7%) (OR = 2.364, 95%CI: 1.272-4.392, P = 0.006) and group B (28.0%) (OR = 1.714, 95%CI: 0.948-3.099, P = 0.073), and the percentage of eyes with IOL prediction errors within ± 1.0 D in Group C (90.9%) was higher than that in group A (67.9%) (OR = 4.758, 95%CI: 2.131-10.626, P < 0.001) and group B (75.0%) (OR = 3.370, 95%CI: 1.483-7.660, P = 0.003) as well. In traumatic aphakic eyes with corneal sutures, IOL power calculation based on the corneal curvature of the injured eye after removing the corneal sutures yields the best refractive outcomes.

Challenges in cataract surgery after penetrating keratoplasty managed using femtosecond laser: A series of 3 case reports.

Cataract surgery in patients after penetrating keratoplasty (PKP) is often challenging because of changes in corneal structure induced by PKP and primary corneal disease. Femtosecond laser-assisted cataract surgery offers several advantages over conventional phacoemulsification, and has been widely used in complicated cataract surgery. We report the use of femtosecond laser-assisted cataract surgery in 3 challenging cases after penetrating keratoplasty. Case 1 involved a patient with hard nuclear grade IV° cataract. After surgery, his corrected distance visual acuity (CDVA) improved from 20/400 to 20/25, and the endothelial cell loss (ECL) % was 12.05 % at 3 months postoperatively. The rotation of the toric IOL in Case 1 was 2°. Case 2 involved a patient with severe nuclear cataract and an endothelial cell density of 837 cells/mm2. After surgery, the CDVA improved from 20/100 to 20/40. The ECL% was 4.06% at 1 week postoperatively. Case 3 was a 91-year-old woman with a short axis length of 21.35 mm and an endothelial cell density number of 1238 cells/mm2. After surgery, the CDVA improved from light perception to 20/133, and the ECL% was 26.09% at 1 week postoperatively; ECL% was 2.67% at 1 month post-operation. The corneal grafts were transparent. Femtosecond laser-assisted cataract surgery seems to be an effective, predictable, and safe approach for challenging patients after PKP, and improves visual recovery and optimal refractive outcomes.

A Study on Refractive Outcome Following Manual Small Incision Cataract Surgery with Rigid PCIOL

Introduction: Cataract is a significant and increasing global problem with vast economic and social implications[1]. It is the principal cause of blindness in India accounting for 62.6% (92). The prevalence of blinding cataract will only increase as people live longer, so cataract will continue to be, by far, the most important treatable cause of blindness. It is estimated that the present number of 20 million of cataract blind will double by year 2030.[2] . Materials and Methods: Study design: Cross sectional observational study Source of data: All the patients admitted with small incision cataract surgery (SICS) with PCIOL implant, in the department of Ophthalmology Rajarajeshwari Medical College and Hospital, Bangalore Study period: 18 months (Jan 2021- June 2022) Sample size: 200 patients. Results and Observations: In our study, at 1st post operative week, most patients had visual acuity score of better than 6/9 and least had less than 6/60 score. A follow up of patients at 2nd week, 6th week and end of 6th week showed that visual acuity improved at 2nd and 6th post-operative weeks.. Most patients were in the refraction range of &lt; -0.50. Conclusion: From our study we conclude that the uncorrected visual acuity of cataract patients improved in the early and late post-operative weeks, after undergoing Manual Small Incision Cataract Surgery with Rigid PCIOL (MSICS) to a great extent. MSICS can be accepted as an alternative to phacoemulsification in developing countries like India. Keywords: Cataract, Small incision, Astigmatic, Visual outcome

Accuracy of using the axial length of the fellow eye for IOL calculation in retinal detachment eyes undergoing silicone oil removal

PurposeEvaluate whether the axial length of the fellow eye can be used to calculate the intraocular lens (IOL) in eyes with retinal detachment.DesignRetrospective, consecutive case series.MethodsOur study was conducted at...

Comparison of Outcomes after Wavefront-optimized and Topography-guided Transepithelial Photorefractive Keratectomy.

To evaluate the outcomes of wavefront-optimized (WFO) and topography-guided (TG) transepithelial photorefractive keratectomy (transPRK) in the treatment of myopia and myopic astigmatism. Patients who underwent transPRK using the WaveLight EX500 excimer laser for the correction of myopia and myopic astigmatism between January 2022 and March 2023 were divided into groups of WFO transPRK (77 eyes of 36 patients) or TG transPRK (63 eyes of 31 patients) in this retrospective, observational cohort study. The preoperative and postoperative 3-month refractive and visual outcomes of the two groups were analyzed. In both groups, the uncorrected distance visual acuity was 0.0 logarithm of the minimum angle of resolution or better in 95% of eyes 3 months postoperatively, and the mean manifest refraction spherical equivalent was within ±1.0 diopter in 90% of eyes. No significant differences were observed between the groups in terms of the uncorrected distance visual acuity or astigmatism. A significant induction of higher order aberrations (HOAs) was observed in both groups. However, the induction of total corneal HOAs (p = 0.014) and spherical aberrations (p &lt; 0.001) was significantly lower in the TG group than that in the WFO group. WFO and TG transPRK effectively improved the visual and refractive outcomes; however, the induction of total corneal HOAs and spherical aberration was lesser following the TG ablation.

Long-Term Results of Sterile Corneal Allograft Ring Segments Implantation in Keratoconus Treatment.

To evaluate the efficacy and safety of sterile corneal allograft ring segments implantation for the treatment of keratoconus by analyzing long-term visual, refractive, and tomographic clinical outcomes. This prospective study included 62 eyes of 49 patients with keratoconus who underwent corneal allograft ring segments implantation at Istanbul Medipol University Faculty of Medicine between February 2020 and August 2022. Surgical outcomes using the Istanbul nomogram were evaluated in patients preoperatively and postoperatively at 1 month, 6 months, 1 year, and 3 years. Outcomes measured were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent (SE), spherical refraction (SR), cylindrical refraction (CR), topographic keratometric values, and corneal thickness at the thinnest point. Preoperative mean UDVA and CDVA (LogMAR) were 0.96 ± 0.50 and 0.72 ± 0.47, respectively, and increased to 0.41 ± 0.34 and 0.22 ± 0.19 at the last visit (P < 0.001). There was a significant decrease in SE, SR, and keratometric values postoperatively (P < 0.001). There was no difference in CR and thinnest corneal thickness values (P = 0.333 and 0.154, respectively). The stromal and epithelial thicknesses measured by anterior segment optical coherence tomography were stabilized at 6 months and 1 year, respectively. No major complications or side effects were observed intraoperatively or postoperatively. This study demonstrated that sterile corneal allograft ring segments implantation is a safe and feasible treatment for keratoconus, yielding notable long-term visual outcomes with minimal implant-related complications.

Сравнительный анализ рефракционных и функциональных результатов имплантации торической интраокулярной линзы с механизмом формирования волнового фронта при хирургическом лечении катаракты у пациентов после сквозной кератопластики

Abstract Comparative analysis of the refractive and functional results of toric intraocular lens with wavefrontshaping mechanism implantation during the surgical treatment of cataracts in patients after penetrating keratoplasty. D.A. Khvan, , G.A. Fedyashev Pacific State Medical University Ministry of Health of Russia, Vladivostok, Russian Federation Primorskii center of eye microsurgery, Vladivostok, Russian Federation Relevance. This study presents a comparative analysis of the effectiveness of toric intraocular lens (IOL) with a wavefront shaping mechanism implantation in cataract surgical treatment in patients after penetrating keratoplasty (PKP). Purpose. To evaluate the effectiveness of toric IOL with a wavefront shaping mechanism implantation in cataract surgical treatment in patients after PKP. Material and methods. This prospective study included 65 patients (65 eyes) who underwent cataract surgery after prevous PKP (the time after removal of corneal sutures averaged 1.4±0.8 years). In the 1st group of patients (34 patients, 34 eyes) the AcrySof IQ Toric IOL was implanted, in the 2nd group – the AcrySof IQ Vivity IOL (31 patients, 31 eyes). In both groups, IOL power was calculated at a target refraction of (–) 0.5 D. The observation period was up to 6 months. Results. In all groups, there was a significant (p&lt;0.001) improvement in uncorrected (UCVA) and best-corrected visual acuity (BCVA) on the first day, after 1, 3 and 6 months. In 1st group, by the 6th month of observation, there was a tendency towards a slight significant (relative to the 3rd month) decrease in UCVA of 0.134±0.1 (p=0.019). In 2nd group, UCVA was significantly (p&lt;0.001) higher than in 1st group at all periods of postoperative follow-up and was 0.075±0.063 before surgery (in 1st group 0.053±0.029), on the first day after surgery 0.348± 0.139 (in the 1st group 0.097±0.05), 1st month 0.516±0.144 (in the 1st group 0.133±0.076), 3rd month 0.642±0.143 and by the 6th month 0.642±0.139 (in 1st group 0.16±0.1 and 0.134±0.1, respectively). Statistically significant (p=0.03) differences were obtained when comparing the error of the spherical equivalent of refraction (SE) from the expected result in the 1st and 2nd groups (1.22±0.875 and 0.76±0.582, respectively) during the observation period up to 6 months. Conclusion. AcrySof IQ Vivity Toric IOL implantation during the cataract surgical treatment in patients with previous keratoplasty allows to obtain significantly higher postoperative UCVA, due to more accurate access to target refraction, which confirmed by a significantly lower spherical equivalent error. Key words: wavefront, cataract, penetrating keratoplasty, EDOF, Vivity

Criteria for premium intraocular lens patient selection.

To discuss available premium intraocular lenses (IOLs), patient selection, and important considerations for each premium IOL. We review important topics and considerations for premium IOL selection: specifically, toric, extended depth of focus (EDOF), multifocal/trifocal, light adjustable lenses (LALs), and small aperture IOLs. Toric lenses are an excellent option for patients with astigmatism. However, to achieve optimal patient satisfaction, it is critical to account for the ATR astigmatism contribution from the posterior cornea and high angle alphas. Additionally, examining the ocular surface prior to placement of EDOF/multifocal IOLs is important, yet the significance of HOAs on outcomes after implantation still must be elucidated more. Finally, recent studies reveal that the small aperture lens is a good alternative for those with corneal irregularities, and second generation LALs are a great option to achieve target refractions in those with less predictable refractive outcomes, such as in Fuchs' dystrophy or in eyes with previous refractive surgery.

We need more network capacity! But why do we get it? Infrastructural refraction and the contingencies of network growth and energy transitions

It is accepted that electricity networks need to grow in scale and scope to facilitate decarbonisation. It is also accepted that infrastructural change is incremental. Yet, the incremental delivery of network capacity and the relevance of this for energy transitions have received little attention. Instead, broader, evolutionary accounts of change predominate. Opportunities therefore remain to conceptualise and study the incrementality of network growth and to consider the implications of this for energy transitions. I conceptualise investment in network capacity as an outcome of infrastructural refraction: as emergent of varied and unevenly distributed histories and geographies of electrification beaming through and being refracted by the prism of socio-technical infrastructure in ways that condition the sited reconstitution of network capacities. Examining practices of translation, enacted by network operators, provides a method of revealing the constitutive details and dynamic of infrastructural refraction. A case study focused on the technological framing of the delivery of a 33 kV substation in Central Manchester is explored. The analysis stresses the importance of examining the contingencies of investment in capacity. This paper contributes a concept-method package that helps reveal such details and by proxy the polycentric politics of electrification, investment in electricity network capacity, and energy transitions.

An Effective Treatment for Progressive Keratoconus with Two-Year Outcomes: Accelerated Epithelium-on Corneal Cross-Linking

Purpose: Corneal collagen cross-linking is a surgical technique for progressive keratoconus. There are several technical modifications with varying clinical outcomes. This study aimed to evaluate the long-term outcomes of the accelerated epithelium-on collagen cross-linking. Design &amp; Methods: A retrospective study was performed on progressive keratoconus patients treated via the accelerated epithelium-on collagen cross-linking who completed the 24th-month follow-up. We included 111 eyes of 77 patients. Clinical variables, including visual acuity, aberrometry, topographic measurements, and refractive outcomes, were evaluated at the postoperative 12th and 24th months. Results: There was a significant improvement in postoperative visual acuity in 50.4% of the patients (p

Cautious application of multifocal intraocular lenses in children with congenital cataracts

Multifocal intraocular lenses (MIOLs) have demonstrated efficacy and safety in adult cataract surgery, yet they encounter many challenges in pediatric applications. This article elaborates on the difficulties in biometric measurements in children, the unpredictability of postoperative refraction outcomes, the lack of long-term spectacle independence in children with MIOLs, the absence of significant advantages in correcting childhood amblyopia, and the potential increase in the rate of secondary surgeries. Due to the insufficient clinical evidence supporting the use of MIOLs in children at present, it is proposed that MIOLs be cautiously applied to children with congenital cataracts in clinical practice. Further research in this area is encouraged.