Long Term Evaluation of Surgically Induced Astigmatism and Corneal Higher-Order Aberrations After 2.2 Mm Clear Corneal Incisions in Femtosecond Laser-Assisted Cataract Surgery: Temporal versus Superior Approach.

Purpose: To assess long term changes of the surgically induced astigmatism (SIA) and corneal higher-order aberrations (HOAs) after 2.2 mm clear corneal incisions (CCIs) in femtosecond laser-assisted cataract surgery and compare them between 2 types of CCIs: temporal and superior approach. Patients and Methods: Patients received the temporal CCIs (Group A) or the superior CCIs (Group B). Outcome measures included visual acuity, manifest refraction, corneal astigmatism, SIA, flattening effect, and corneal HOAs. Correlation between postoperative corneal HOA and SIA at each follow-up were analysed. Results: This study assessed data from 106 eyes, of which 64 in Group A and 42 in Group B. The two groups had similar postoperative visual acuity of distance, intermediate and near (all P > 0.05). SIA and corneal HOAs were significantly lower in Group A than Group B in the early postoperative period, while there was no significant difference in the late postoperative period. At 6 months after surgery, the arithmetic mean of SIA over corneal 4mm zone was 0.33 ± 0.19D for temporal incision, and 0.37 ± 0.25D for superior incision. For Group A, the correlations of HOAs and SIA persisted from 1 week to 6 months after surgery. For Group B, the changes in corneal HOAs were significantly related to the SIA at 1 week and 1 month postoperatively. Conclusion: This study suggested the consistency of increasing and recovering process of corneal HOAs and SIA after surgery. Compared to the superior incisions, temporal incisions might induce quicker corneal recovery and less change in SIA and corneal HOAs.

Non-diffractive, toric, extended depth-of-focus intraocular lenses in eyes with low corneal astigmatism.

BACKGROUND: To assess clinical outcomes after implanting toric, extended-depth-of-focus intraocular lenses (IOLs) to correct low corneal astigmatism in eyes with cataracts. METHODS: 47 eyes were implanted with the AcrySof IQ Vivity Toric DFT215 IOL. Main outcome measures were refractive error, monocular uncorrected and corrected distance (UDVA/CDVA), uncorrected and distance-corrected intermediate (UIVA/DCIVA), and uncorrected near and distance-corrected near (UNVA/DCNVA) visual acuities, monocular defocus curve, rotational stability, and IOLSAT and QUVID questionnaires. Patients were assessed at 3 months postsurgery. RESULTS: All eyes had a postoperative spherical equivalent (SE) within ± 0.50 D and 97.87% (n = 46) had a refractive cylinder ≤ 0.50 D. The mean SE and refractive cylinder were - 0.10 ± 0.17 D and - 0.16 ± 0.24 D, respectively. The CDVA was ≥ 20/25 and ≥ 20/32 in 95.74% (n = 45) and 97.87% (n = 46) of eyes, respectively. The DCIVA was ≥ 20/32 in 85.11% (n = 40) of eyes and the DCNVA was ≥ 20/40 in 74.47% (n = 35). The mean values of CDVA, DCIVA, and DCNVA were - 0.02 ± 0.08, 0.14 ± 0.09, and 0.23 ± 0.12 logMAR, respectively. The defocus curve revealed good visual acuity at far and intermediate distances with a depth-of-focus of about 1.75 D. IOL rotation was 0.74 ± 1.13 degrees and all eyes had a rotation of less than 5 degrees. Patients reported either good or very good postoperative vision without eyeglasses under bright-light-conditions at distance (87.80%, 36/41) and intermediate distance (92.68%, 38/41). Between about 63.83%-72.34% (30-34) of patients reported no starburst, halos, or glare, or if experienced, were not bothersome. CONCLUSIONS: The Vivity toric IOL implanted in eyes with low-astigmatism provides accurate refractive outcomes, good visual acuity at different distances and excellent rotational stability. Trial Registration The study was registered with the German Clinical Trials Register (DRKS00030579).

Wear Experiences with Two Soft Contact Lenses for Astigmatism of Different Modalities.

Introduction: Patients expect to have excellent vision and comfort when wearing soft contact lenses. The purpose of this study was to compare the wear experiences of participants with astigmatism when wearing a daily disposable soft toric lens to an established, commonly used reusable toric lens. Methods: In this crossover study, habitual soft toric lens wearers were fit with a daily replacement soft toric lens (delefilcon A) and a reusable, 1-month replacement soft toric lens (comfilcon A) in a randomized order. After 30 days of wear, Visual analog scale (VAS) surveys were used to assess wear experience, including vision and comfort, for overall wear and end-of-day wear. Scores were compared statistically with mixed-effects linear models. Participants also responded to questions about convenience, ease of use, and satisfaction with both lenses and preference questions based upon comfort, vision, and overall performance. Results: Fifty-nine participants completed the multi-site crossover study. VAS scores [mean(std dev)] for overall quality of vision for the delefilcon A [80.4(16.4)] and comfilcon A [66.8(27.7)] lenses were statistically significant (P=0.002). The difference in the mean overall comfort scores for the delefilcon A lenses [71.6(26.3)] and comfilcon A lenses [63.2(28.9)] was 8.4, which exceeds the establish criteria for clinical significance, although not statistically significant (P=0.08). Overall satisfaction scores were 68.8(26.9) for the delefilcon A and 59.7(30.3) for the comfilcon A lenses (P=0.08). Both lenses provided mean binocular visual acuities better than 20/20 Snellen equivalent. Over half of the participants preferred the delefilcon A lenses based upon comfort, vision, and overall performance. Convenience, ease of use, and satisfaction all scored higher with delefilcon A lenses. Conclusion: The results of this study show that wear experience with delefilcon A lenses for astigmatism can meet or exceed that of comfilcon A toric lenses while also providing healthy, daily disposable lens wear.

Accuracy of Toric Intraocular Lens Calculators with Predicted and Measured Posterior Corneal Astigmatism Across Different Types of Astigmatism.

INTRODUCTION: This study is a retrospective case series to compare the accuracy of the Barrett toric calculator using predicted posterior corneal astigmatism (PCA) and PCA measurements using swept-source optical coherence tomography (SS-OCT) and a Scheimpflug camera. This evaluation was conducted across different types of anterior and posterior astigmatism. METHODS: A total of 146 eyes from 146 patients implanted with toric intraocular lenses were included. Mean absolute prediction error, standard deviation of prediction error, and the percentage of eyes with prediction errors within ±0.50 diopters (D) were calculated using vector analysis. Biometric measurements were conducted using the IOLMaster 700 and Pentacam HR. A subgroup analysis was conducted based on the orientation of both anterior and posterior corneal astigmatism. RESULTS: The Barrett toric calculator with predicted PCA yielded the best results, with 78.1% having a prediction error ≤ 0.50 D, which was a significantly higher percentage than the Barrett formula with the two versions of measured PCA (P < 0.05). In the subgroup with a horizontally steep meridian PCA using the IOLMaster 700, the Barrett formula with predicted PCA yielded the best results, with 78.3% of cases having a prediction error of less than 0.5 D. This percentage was significantly higher than the other two measured PCA subgroups (P < 0.05). CONCLUSION: The Barrett toric formula with predicted PCA demonstrated a statistically significantly higher proportion of cases with a prediction error ≤ 0.5 D compared to the two measured PCA formulas (from the IOLMaster 700 or Pentacam). This trend persisted even when the posterior corneal astigmatism was horizontally steep.

Effect of Long-Acting Diquafosol Sodium on Astigmatism Measurement Repeatability in Preoperative Cataract Cases with Dry Eyes: A Multicenter Prospective Study.

INTRODUCTION: Dry eye can compromise corneal astigmatism measurement repeatability during preoperative cataract surgery examination. No previous studies have analyzed the effectiveness of long-acting 3% diquafosol sodium (LA-DQS) on astigmatism measurement repeatability. This research assessed the effect of LA-DQS on astigmatism measurement repeatability in preoperative patients with cataract and short tear break-up time (TBUT) type dry eyes in both eyes of the same patient. Correlations between repeatability and TBUT, corneal high-order aberrations (HOAs), and corneal astigmatism magnitude were also analyzed. METHODS: In total, 122 eyes (61 patients) with short TBUT-type dry eye were enrolled. Preoperatively, only one eye of all patients was treated with LA-DQS for 4 weeks. TBUT and corneal HOAs were checked using CASIA 2 before and 4 weeks post-treatment. The cylindrical power and meridian of astigmatism were measured at 3- and 4-week post-treatment using IOLMaster 700. Power vectors J0 and J45 were used for astigmatism calculations. Repeatability of astigmatism measurements was assessed as the within-subject standard deviation (Sw). The relative effects of TBUT and HOAs on J0 Sw and J45 Sw were also analyzed. Comparative changes in these variables were evaluated between treated and non-treated eyes, with additional analysis of their correlations. RESULTS: Treated eyes exhibited significant improvements in TBUT, HOAs, and post-treatment measurements of J0 Sw and J45 Sw at 3 and 4 weeks. In non-treated eyes, J0 Sw and J45 Sw showed significant correlation with TBUT and corneal HOAs. HOAs showed stronger relative associations with J0 Sw and J45 Sw than TBUT. In non-treated eyes, no significant correlation was found between cylindrical power and astigmatism measurement repeatability. CONCLUSIONS: In short TBUT-type dry eye, preoperative treatment with LA-DQS significantly improved astigmatism measurement repeatability. This may improve the precision of intraocular lens (IOL) power calculations regardless of the magnitude of corneal astigmatism, especially when toric IOLs are used.

Timing optimization for primary pterygium excision with conjunctival-limbal autograft to restore the corneal optical properties.

PURPOSE: To propose the optimal value of baseline corneal astigmatism and pterygial morphological profiles for primary pterygium surgery to restore the corneal optical properties. METHODS: We analysed 93 eyes from 84 subjects with nasal-only primary pterygium who underwent pterygium excision with conjunctival-limbal autograft and were assessed perioperatively using anterior segment swept-source optical coherence tomography (AS SS-OCT). We collected data on anterior corneal astigmatism (ACA) and root mean square (RMS) values for anterior corneal lower- (LoA) and higher-order aberrations (HoA) as corneal optical properties using AS SS-OCT. Using preoperative ACA and four pterygial morphological profiles (horizontal invasion length [HIL], height, thickness and the ratio of residual corneal thickness [RCT] to central corneal thickness [CCT]) measured in AS SS-OCT, we plotted receiver operating characteristic (ROC) curves. These curves aimed to determine cut-off values predicting a perioperative decrease exceeding 50% in ACA, RMS LoA and RMS HoA, as well as postoperative residual ACA higher than 1.25D. RESULTS: Preoperative ACA > 1.42D (AUC = 0.934) and >3.60D (AUC = 0.946) proved most effective in identifying subjects with perioperative decrease exceeding in ACA and RMS LoA, respectively. HIL > 3.34 mm (AUC = 0.941) was most effective in distinguishing subjects with perioperative reduction exceeding 50% in RMS HoA. Preoperative ACA > 5.78D (AUC = 0.776) and HIL > 5.03 mm (AUC = 0.700) significantly distinguished subjects with postoperative residual ACA higher than 1.25D. CONCLUSION: Optimizing the restoration of corneal astigmatism and aberrations after pterygium surgery may be facilitated by determining the optimal surgical timing based on preoperative ACA and HIL values.

Prevalence data for total corneal astigmatism in cataract patients.

PURPOSE: To report the prevalence data for total corneal astigmatism (TCA) in cataract patients. METHODS: The authors retrospectively collected and analyzed the preoperative biometric data of the patients who underwent cataract surgery in the Department of Ophthalmology, Peking University Third Hospital, from January 2019 to May 2023. RESULTS: The mean age of the 10817 patients was 71 ± 10 years; the male/female ratio was 4653/6164. The mean TCA obtained by the IOLMaster 700 (Carl Zeiss Meditec AG, Jena, Germany), the Abulafia-Koch (AK) formula, and the Barrett toric calculator was 1.11 ± 0.81 diopter (D), 1.13 ± 0.75 D, and 1.12 ± 0.74 D respectively, which was significantly greater than the mean standard keratometric (K) astigmatism (0.99 ± 0.75 D) obtained by IOLMaster 700. Against-the-rule (ATR) astigmatism was dominant in all the TCA measurements, and its proportion increased with age. TCA measurements by different methods exhibit high variability, with a total of 1574 (8.9%) data sets from 1016 (9.4%) patients showing a difference larger than 0.5 D in at least one pair of TCA measurements. CONCLUSION: The use of TCA rather than K astigmatism significantly influenced the choice of intraocular lenses (IOLs) as more patients would be candidates for toric IOLs. It was essential to carefully compare and select TCA obtained with multiple methods for optimal postoperative visual quality.

Meridional analysis for calculation of the toric power of phakic IOLs.

PURPOSE: To present a reproducible method to calculate the toricity needed at the intraocular lens (IOL) plane with toric phakic IOLs (ICL, Staar Surgical) and compare its results with those obtained with the online calculator provided by the manufacturer. DESIGN: Retrospective case series. SETTING: Private practice, Buenos Aires, Argentina. METHODS: The formula originally described by Holladay to calculate the IOL power in phakic eyes was used to calculate the required spherical power along the less refractive meridian and along the more refractive meridian. Meridional analysis was applied to calculate the required toricity at the IOL plane and the surgically induced corneal astigmatism was incorporated into the calculations. The refractive cylinder predicted by this method and by the online calculator of the manufacturer were compared to the postoperative refractive cylinder by means of vector analysis. The possible changes in the ratio of toricity in patients with different amounts of astigmatism and anterior chamber depth are assessed in a theoretical section. RESULTS: In 35 eyes, the measured mean postoperative refractive cylinder was 0.09 D @ 99°, the mean predicted postoperative refractive astigmatism was 0.04 D @ 102° according to the manufacturer's online calculator and 0.09 D @100° according to our method. With both methods, 91.43% of eyes had an absolute cylinder prediction error within ±0.50 diopters. CONCLUSIONS: The method described in this article to calculate the toricity of phakic IOLs has a refractive accuracy similar to that of the original calculator developed by the manufacturer.

Evaluation of objective and subjective binocular ocular refraction with looking in type.

BACKGROUND: This study aimed to compare the results of the Chronos binocular/monocular refraction system, that measures objective and subjective ocular refraction in one unit, to objective findings obtained from a conventional autorefractometer and a conventional subjective ocular refraction using a trial-frame in real space. METHODS: Twenty-eight healthy volunteers (21.2 ± 1.5 years old) were included in this study. Objective ocular refraction was measured using two tests: the Chronos binocular/monocular refraction system under binocular conditions and a conventional autorefractometer under monocular conditions. Subjective ocular refraction was measured using three tests: Chronos binocular/monocular refraction system under binocular, monocular conditions, and trial-frame in the real space under monocular conditions. The measurement distance was set to 5.0 m for each test. All ocular refractions were converted into spherical equivalents (SEs). RESULTS: The objective SE was significantly more negative with Chronos binocular/monocular refraction system under binocular condition (- 4.08 ± 2.76 D) than with the conventional autorefractometer under monocular condition (- 3.85 ± 2.66 D) (P = 0.002). Although, the subjective SE was significantly more negative with Chronos binocular/monocular refraction system under binocular condition (- 3.55 ± 2.67 D) than with the trial-frame in the real space under monocular condition (- 3.33 ± 2.75 D) (P = 0.002), Chronos binocular/monocular refraction system under monocular condition (- 3.17 ± 2.57 D) was not significantly different from that in trial-frame in real space under monocular condition (P = 0.33). CONCLUSION: These findings suggest that the Chronos binocular/monocular refraction system, which can complete both objective and subjective ocular refraction tests in a single unit, is suitable for screening ocular refraction, although it produces slightly more myopic results. Furthermore, subjective ocular refraction testing accuracy in Chronos binocular/monocular refraction system can be equivalent to trial-frame in real-space testing by switching from binocular to monocular condition.

Visual and Refractive Outcomes of a New Hydrophobic Trifocal Toric Intraocular Lens.

Purpose: To evaluate the visual outcomes and efficacy of astigmatism correction using a new hydrophobic trifocal toric intraocular lens (IOL). Methods: This study involved 62 eyes implanted with the FineVision HP Toric IOL. The visual and refractive outcomes were assessed preoperatively and 6 weeks after the surgery. Specifically, monocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA) at 80 and 60 cm and uncorrected near visual acuity at (UNVA) at 40 cm were evaluated. The rotational stability of the lens was also assessed. Results: Sixty-one eyes (98.39%) were within ±1.00D and 55 eyes (88.71%) were within ±0.50 D of spherical equivalent, with a mean value of 0.09±0.39 D. 51 (82.26%) and 61 (98.39%) eyes had a UDVA of ≥20/20 and ≥20/25, respectively, and for CDVA these values were as follows: 59 (95.16%) and 62 eyes (100%), respectively. The mean UDVA and CDVA were 0.01±0.06 and -0.01±0.04logMAR, respectively. Greater than or equal to unaided 20/20 vision was achieved at 40 cm in 42 (67.74%), UIVA at 60 cm in 42 (67.74%) and 50 eyes (80.65%) at 80 cm. Those achieving ≥20/25 were 56 (90.32%, 40 cm), 59 (95.16%, 60 cm), and 62 eyes (100%, 80 cm). Postoperative mean values were 0.04±0.07, 0.03±0.07, and 0.00±0.07logMAR for UCNVA, UIVA at 60 cm, and UIVA at 80 cm, respectively. The mean rotation of the IOL was 5.8 degrees. Conclusion: This hydrophobic trifocal toric IOL provides good refractive outcomes with excellent visual acuity across multiple distances, providing a full range of focus.

Association between maternal fasting glucose levels throughout pregnancy and preschoolers' refractive errors.

PURPOSE: We aimed to investigate the association between maternal fasting plasma glucose (FPG) trajectories during pregnancy and children's refractive errors at 6 years old. DESIGN: Based on the Ma'anshan Birth Cohort (MABC) in China, a total of 1987 mother-child pairs were included in this study. METHODS: Using the group-based trajectory model, trajectory fitting was performed on fasting blood glucose levels during the first, second, and third trimesters of pregnancy. Children's vision was measured at 6 years of age using the standard logarithmic visual acuity E-chart and cycloplegic refraction examination. Logistic regression models and multi-informant generalized estimating equations were used to analyze the association between maternal blood glucose level and 6-year-old children's visual acuity. RESULTS: Children born of mothers with high level FPG trajectory had a higher risk of developing refractive error [OR=1.46 (95% CI 1.08 1.97)], hypermetropia [OR=1.64 (95% CI 1.09, 2.46)] and astigmatism [OR=1.60 (95% CI 1.06, 2.41)] at age six compared to those with low level trajectory. Maternal blood glucose level in the first [ß=-0.012 (95% CI -0.024, -0.001)] and the second [ß=-0.016 (95% CI -0.025, -0.006)] trimesters was associated with 6 year children's distance vision value. CONCLUSIONS: High level of fasting plasma glucose trajectories during pregnancy has been observed to be associated with 6-year-old children's refractive error, hypermetropia and astigmatism. The first and the second trimesters may be critical periods for the effects of maternal blood glucose on children's vision. The long-term effect of maternal glucose metabolism on children's visual development deserves further study.

Comparative Analysis of Corneal Higher-Order Aberrations after Laser-Assisted In Situ Keratomileusis, Photorefractive Keratectomy, and Small Incision Lenticule Extraction with Correlations to Change in Myopic Q-Value and Spherical Equivalent with and without Astigmatism.

Background: This retrospective chart review compared the higher-order aberrations (HOAs) among photorefractive keratectomy (PRK), laser-assisted in situ keratomileusis (LASIK), and small incision lenticule extraction (SMILE) alongside changes in spherical equivalent (SEQ) and corneal shape (Q-value). Methods: Analyzing 371 myopic eyes, including 154 LASIK, 173 PRK, and 44 SMILE cases, Pentacam imaging was utilized pre-operatively and at one-year post-operative visits. Results: All procedures resulted in 100% of patients achieving an uncorrected distance visual acuity (UDVA) of 20/40 or better, with 87% of LASIK and PRK, and 91% of SMILE patients having 20/20 or better. Significant increases in HOAs were observed across all procedures (p < 0.05), correlating positively with SEQ and Q-value changes (LASIK (0.686, p < 0.05), followed by PRK (0.4503, p < 0.05), and SMILE (0.386, p < 0.05)). Vertical coma and spherical aberration (SA) were the primary factors for heightened aberration magnitude among the procedures (p < 0.05), with the largest contribution in SMILE, which is likely attributed to the centration at the corneal apex. Notably, PRK showed insignificant changes in vertical coma (-0.197 µm ± 0.0168 to -0.192 µm ± 0.0198, p = 0.78), with an increase in oblique trefoil (p < 0.05). Conclusions: These findings underscore differences in HOAs among PRK, LASIK, and SMILE, helping to guide clinicians.

Comparison of photorefraction by Plusoptix A12 and cycloplegic autorefraction in children.

BACKGROUND: Plusoptix photoscreeners are capable of measuring refractive errors of children from 1 meter distance, without cyloplegia. We aimed to compare refractive data obtained from the newest version of Plusoptix (model 12) with cycloplegic autorefraction. METHODS: We examined 111 consecutive children aged 3-7 years first by Plusoptix A12C under manifest condition and subsequently for cycloplegic refraction by Topcon KR-1 tabletop autorefractometer. Sphere, spherical equivalent, cylinder and axis of astigmatism measured by the two methods were analyzed to determine correlation, agreement and differences. RESULTS: Binocular examination of 111 children aged 4.86±1.27 years revealed good agreement between refractive data obtained by Plusoptix and cycloautorefraction, according to Bland-Altman plots. Significant (p < 0.001) and strong correlation was found between all refractive measurements (Pearson's r value of 0.707 for sphere, 0.756 for pherical equivalent, and 0.863 for cylinder). Plusoptix mean sphere, spherical equivalent and cylinder were 1.22, 0.56, and -1.32 D, respectively. Corresponding values for cycloautorefraction were 1.63, 1.00, and -1.26 D. The difference between axis of cylinder measured by the two methods was < 10° in 144 eyes (64.9%). CONCLUSIONS: Considering the significant agreement and correlation between Plusoptix photoscreener and cycloplegic autorefraction, the need for cycloplegic drops in refractive examination of children may be obviated. The mean difference between cylinder measurements are considerably trivial (0.06 D), but sphere is approximately 0.4 D underestimated by Plusoptix compared to cycloautorefraction, on average.

Clinical Results of a Trifocal Toric Intraocular Lens Using the Holladay Total Surgically Induced Astigmatism Formula for Correcting Low Corneal Astigmatism in Japanese Patients.

Purpose: To evaluate the effectiveness and safety of the AcrySof IQ PanOptix toric intraocular lens (IOL) with cylinder power of 1.0 D (TFNT20) in a Japanese population with low corneal astigmatism and compare with historical control data for nontoric IOLs. Setting: Tokyo Dental College Suidobashi Hospital, Tokyo, Japan. Design: Prospective, single-center study. Methods: Patients ≥20 years old received TFNT20 IOL in at least 1 eye based on Alcon Toric calculator (Holladay Total surgically induced astigmatism). Effectiveness endpoints included the percentage of eyes with refractive cylinder ≤0.25 D at 30-60 days after surgery, which was compared with a historical control threshold rate of 29.2% for nontoric IOLs and refractive cylinder ≤0.50 D. Monocular uncorrected distance visual acuity (UDVA; 5 m), uncorrected intermediate visual acuity (UIVA; 60 cm), uncorrected near visual acuity (UNVA; 40 cm), and adverse events were evaluated. Results: Of 41 eyes implanted with TFNT20 IOLs, 37 eyes (90%) achieved refractive cylinder ≤0.25 D at 30-60 days after surgery, demonstrating the superiority of TFNT20 compared with historical data (P<0.0001). Refractive cylinder of ≤0.50 D was achieved by 41 eyes (100%). At 30-60 days, mean ± SD monocular CDVA was -0.15 ± 0.07 logMAR, UDVA was -0.09 ± 0.09 logMAR, UIVA was -0.00 ± 0.07 logMAR, and UNVA was 0.03 ± 0.07 logMAR. Six eyes (15%) had elevated postoperative intraocular pressure, which returned to normal and was not device-related. Conclusion: TFNT20 IOLs successfully reduced postoperative refractive cylinder and provided good distance, intermediate, and near uncorrected VAs in Japanese patients with low corneal astigmatism.

Assessment of a Clinical Test for Detection of Alteration in Visual Perception Due to Astigmatism.

Purpose: Astigmatism blurs the retinal image of a circular spot along a particular orientation rendering it an elliptical shape. Astigmatic patients demonstrate adaptation to residual astigmatic blur that may affect their discrimination between oval and circular targets. The Wilkins Egg and Ball Test (WEBT) was created to detect altered visual perception due to residual astigmatic blur by discriminating a circle within a row of oval elements. This prospective, cross-sectional study examined the utility of WEBT in detecting uncorrected residual astigmatism on the perception of form symmetry in astigmatic and keratoconic participants as well as normal participants with induced astigmatism at four primary meridians. Methods: The mean search time (sT) and number of errors (noE) of 33 non-astigmatic controls (mean age: 24±5, range: 18-43, 6 males), 23 astigmatic participants (mean age: 36±12, range: 18-43, 6 males) and 13 keratoconic participants (N=22 eyes, mean age: 36±12, range: 18-58, 6 males) were measured under baseline, and 2.00 DC induced cylinder at four primary meridians, and for uncorrected, spherical-correction only, and fully corrected conditions, respectively. Mean sT and noE were converted to Z-scores, combined for each condition, and compared using repeated measures ANOVA with post-hoc analysis. Results: Combined Z-scores for the controls were significantly worse (p<0.001) for all induced cylinder conditions. The induced 180° condition was significantly better than 45° and 90° conditions (p=0.04), but not the 135° condition. For both astigmatic and keratoconic cohorts, Z-scores of the uncorrected condition were significantly worse than the fully corrected condition (both p<0.01), but the fully corrected and spherical-only conditions did not differ significantly (p=0.06 and p=0.05, respectively). Conclusion: In accommodating young adults, WEBT detected altered visual perception due to overall blur, and moderate-high amounts of uncorrected induced astigmatism and keratoconus, but is not useful as a tool for detection of altered visual perception due to small residual astigmatic blur.

Severe astigmatism secondary to large intraocular lens pantoscopic tilt because of a malpositioned haptic following cataract surgery.

An 80-year-old woman presented with painless blurring of vision and monocular diplopia in her left eye following routine phacoemulsification and monofocal intraocular lens (IOL) implantation 5 weeks earlier. Her uncorrected visual acuity (VA) was 6/60 correctable with pinhole to 6/21. Her best-corrected VA was 6/15 with a subjective refraction of -0.50DS/-5.25DCx37. Her corneal astigmatism was -1.25DCx74. Ophthalmic examination disclosed a severely tilted single-piece posterior chamber IOL in the capsular bag. The inferior portion of the optic was tilted posteriorly because of a twisted and malpositioned haptic. The patient underwent remedial surgery to untwist and reposition the IOL haptic which led to immediate improvement of the IOL position. Her uncorrected VA improved to 6/12-2 correctable with pinhole to 12+1 with an autorefraction of +0.25DS/-2.00DCx74 on the first postoperative day. One month postoperatively, her best-corrected VA was 6/12 with a refraction of +0.50DS/-2.50DCx82. Her final vision was limited by myopic macular degeneration.

Effect of Cyclotorsion Compensation in Small Incision Lenticule Extraction Surgery for the Correction of Myopic Astigmatism: A Systematic Review and Meta-Analysis.

INTRODUCTION: Small incision lenticule extraction (SMILE) has made notable advancements in addressing myopic astigmatism. Nevertheless, the potential impact of cyclotorsion on surgical outcomes cannot be overlooked. This study aims to assess the effectiveness of cyclotorsion compensation technology in SMILE surgery for the correction of myopic astigmatism, examining its influence on postoperative visual quality. METHODS: A systematic review and meta-analysis were conducted. A comprehensive literature search was performed using databases, including PubMed, Web of Science, EMBASE, Cochrane Library, EBSCO, Scopus, CNKI, VIP, and Wan Fang. Studies meeting the criteria were selected and included. Data were independently extracted by three authors. Clinical outcome parameters were analyzed using Review Manager version 5.3. RESULTS: This meta-analysis included ten studies. The results showed that, compared with the control group (cyclotorsion compensation was not performed in SMILE), the following indicators in the cyclotorsion compensation group were: residual astigmatism (RA) [weighted mean difference (MD) = 0.73, 95% confidence interval (CI) + 0.26 to + 1.19, P = 0.002], spherical equivalent (SE) (MD = 1.99, 95% CI + 0.77 to + 3.21, P = 0.001), coma (MD = -0.06, 95% CI -0.08 to -0.04, P < 0.00001), higher-order aberrations (HOAs) (MD = -0.04, 95% CI -0.06 to -0.02, P < 0.0001), follow-up 6-month angle of error (AE) (MD = -2.67, 95% CI -3.71 to -1.63, P < 0.00001), and follow-up 6-month uncorrected distance visual acuity (UDVA) (MD = -0.05, 95% CI -0.08 to -0.01, P = 0.005), and the differences in results were statistically significant. However, the differences among correction index, index of success (IOS), targeted induced astigmatism (TIA), magnitude of error (ME), and spherical aberration (SA) were not statistically significant. CONCLUSION: Cyclotorsion compensation proves to be effective and predictable for correcting myopic astigmatism. The cyclotorsion compensation group demonstrated advantages over the control group in terms of postoperative residual astigmatism, and it induced fewer coma aberrations. Whether cyclotorsion compensation can lead to better visual quality remains to be seen, and further research on correcting myopic astigmatism through cyclotorsion compensation is warranted.

Astigmatism Management in Modern Cataract Surgery.

Astigmatism management is a frequently encountered challenge in the world of modern cataract surgery. This review article investigates the importance of astigmatic correction and seeks to uncover the critical components of preoperative evaluation. With the rapid growth of new technologies and techniques, this article aims to also catalogue and clarify the multitude of astigmatism treatment options available for the cataract surgeon.

Correlation of Refractive Error with Anisometropia Development in Early Childhood.

PURPOSE: This study aims to investigate the relationship between the type and severity of refractive error and anisometropia development in preschool children. DESIGN: Retrospective cohort study. METHODS: Data from Maccabi Healthcare Services, Israel's second-largest Health Maintenance Organization (HMO), were analyzed. The study included all isometropic children aged 1-6 years, re-examined for refraction at least two years following their initial examination between 2012 and 2022. Anisometropia was defined as a ≥1 diopter interocular difference in spherical equivalent. Relationships were assessed using logistic regression models adjusted for key sociodemographic factors. RESULTS: Among 33,496 isometropic children (51.2% male, mean age 3.2 ± 1.5 years), the prevalences of emmetropia, myopia, and hyperopia were 26.7% (n=8,944), 4.2% (n=1,397), and 69.1% (n=23,155), respectively. Over a mean follow-up period of 5.1 ± 2.4 years, 2,593 children (7.7%) were diagnosed with anisometropia. Adjusted odds ratios (ORs) for anisometropia gradually increased with baseline refractive error severity, reaching 13.90 (5.32-36.34) in severe myopia and 4.19 (3.42-5.15) in severe hyperopia. This pattern was also evident in cylindrical anisometropia, where ORs increased with greater baseline astigmatism, peaking at 12.10 (9.19-15.92) in children with high astigmatism (≥ 3 D). Associations remained consistent in sensitivity and subgroup analyses including across both genders and when using a stricter anisometropia criterion. CONCLUSION: Children aged 1-6 years, initially without anisometropia but showing increasing severity of myopia, hyperopia, or astigmatism, are more likely to develop anisometropia. This underscores the importance of follow-up refractive measurements within this population to promptly diagnose and treat anisometropia and prevent potential visual complications.

Keratoconus: exploring fundamentals and future perspectives - a comprehensive systematic review.

Background: New developments in artificial intelligence, particularly with promising results in early detection and management of keratoconus, have favorably altered the natural history of the disease over the last few decades. Features of artificial intelligence in different machine such as anterior segment optical coherence tomography, and femtosecond laser technique have improved safety, precision, effectiveness, and predictability of treatment modalities of keratoconus (from contact lenses to keratoplasty techniques). These options ingrained in artificial intelligence are already underway and allow ophthalmologist to approach disease in the most non-invasive way. Objectives: This study comprehensively describes all of the treatment modalities of keratoconus considering machine learning strategies. Design: A multidimensional comprehensive systematic narrative review. Data sources and methods: A comprehensive search was done in the five main electronic databases (PubMed, Scopus, Web of Science, Embase, and Cochrane), without language and time or type of study restrictions. Afterward, eligible articles were selected by screening the titles and abstracts based on main mesh keywords. For potentially eligible articles, the full text was also reviewed. Results: Artificial intelligence demonstrates promise in keratoconus diagnosis and clinical management, spanning early detection (especially in subclinical cases), preoperative screening, postoperative ectasia prediction after keratorefractive surgery, and guiding surgical decisions. The majority of studies employed a solitary machine learning algorithm, whereas minor studies assessed multiple algorithms that evaluated the association of various keratoconus staging and management strategies. Last but not least, AI has proven effective in guiding the implantation of intracorneal ring segments in keratoconus corneas and predicting surgical outcomes. Conclusion: The efficient and widespread clinical translation of machine learning models in keratoconus management is a crucial goal of potential future approaches to better visual performance in keratoconus patients. Trial registration: The article has been registered through PROSPERO, an international database of prospectively registered systematic reviews, with the ID: CRD42022319338.

Keratoconus: from fundamentals to future Artificial intelligence has changed how we treat the eye disease keratoconus in recent years. This study examines the many keratoconus therapies available, including surgery and contact lens wear, and how artificial intelligence can improve the safety and accuracy of these procedures. We combed through numerous papers to locate this data. To achieve the best outcomes, several parameters and methods should be evaluated. According to the study, some elements from eye scans are more useful than others. The idea behind using artificial intelligence is to help patients see better and treat keratoconus more effectively.