Spherical Equivalent Research Articles

Excimer Laser-Assisted Deep Anterior Lamellar Keratoplasty Versus Penetrating Keratoplasty for Patients With Keratoconus: A Retrospective Analysis From the Homburg Keratoconus Center.

To evaluate the outcome of excimer laser-assisted deep anterior lamellar keratoplasty (Exc-DALK) and penetrating keratoplasty (Exc-PKP) for keratoconus (KC). We included 123 eyes and compared the outcome of 30 eyes undergoing big-bubble Exc-DALK after stromal debulking (G1) against a matched group of 83 eyes undergoing Exc-PKP (G2) in our department. G2 was created after performing a pseudorandom stratified bootstrapping of our PKP database starting with 2802 surgeries with removal of any bias. Main outcomes included best corrected visual acuity (BCVA), spherical equivalent (SE), tomographic changes, and endothelial cell density (ECD). Data were compared preoperatively, postoperatively with 2 double-running cross-stitch sutures according to Hoffmann [2 and 10 months postoperatively (T1 and T2)], after first suture removal [15 months postoperatively (T3)], and after final suture removal [26 months postoperatively (T4)]. Preoperatively, all parameters were comparable without significant differences. At T1, G1 showed significantly better BCVA (P = 0.01), lower SE (P = 0.04), lower anterior and posterior topographic astigmatism (ATA and PTA, P < 0.01), lower maximal keratometry (P = 0.02), and lower central corneal thickness (P < 0.01). At T2, G1 showed significantly better BCVA (P = 0.04), lower PTA (P < 0.01), and higher ECD (P < 0.01). At T3, G1 showed significantly lower ATA (P = 0.01) and PTA (P < 0.01) and higher ECD (P = 0.02). At T4, G1 showed significantly lower PTA and higher ECD (P < 0.01) but no significant difference in BCVA (P = 0.07). Exc-DALK provided faster visual rehabilitation and represented an endothelial cell-sparing method compared with Exc-PKP. After final suture removal, Exc-DALK showed noninferior outcomes compared with Exc-PKP if the graft was placed on naked Descemet membrane.

Accuracy of intraoperative aberrometry versus preoperative biometry for intraocular lens power selection in short and long eyes.

To compare the accuracy of intraoperative wavefront aberrometry using the ORA VLynk system with different biometry-based formulas in short and long eyes after cataract surgery. This prospective study considered 48 eyes with axial lengths of <22.1 mm and 48 eyes with axial lengths of >25.0 mm. All eyes were implanted with the monofocal AcrySof IQ IOL, the power being determined using the ORA VLynk. The postoperative spherical equivalent (SE) at 3 months was compared to that predicted preoperatively using the SRK/T, Hoffer Q, Haigis, Holladay 2, Barrett Universal II, and Barrett True K formulas and intraoperatively using the ORA VLynk. Mean numerical and absolute errors and the percentage of eyes within ±0.50 D/1.00 D of their target were obtained. For long eyes, the mean absolute error values were 0.35, 0.52, 0.34, 0.30, 0.29, 0.27, and 0.24D for SRK/T, Hoffer Q, Haigis, Holladay 2, Barrett Universal II, Barrett True K, and ORA VLynk, respectively (p < 0.001). These values were 0.55, 0.45, 0.49, 0.40, 0.44, 0.44 and 0.50 D for short eyes, respectively (p < 0.001). The proportions of long eyes within ±0.50 D of the target were 77.08, 50, 75, 85.42, 83.33, 79.17, and 87.50%, respectively; and 50, 66.67, 60.42, 66.67, 60.42, 60.42, and 58.33%, respectively, for short eyes. The ORA VLynk performs better than all biometry-based formulas in long eyes and, in short eyes, it is as effective as SRK/T, Haigis, Barrett Universal II, and Barrett true K, with the Hoffer Q and Holladay 2 being the most accurate; however, the differences between the calculation methods were small. Identifier DRKS000028106.

Visual and patient reported outcomes provided by a refractive multifocal intraocular lens based on continuous transitional focus

PurposeTo analyze the quality of vision of patients implanted bilaterally with the multifocal Precizon Presbyopic intraocular lens (IOL), as well as to evaluate the visual performance provided by the lens.SettingVissum Miranza Alicante.DesignProspective multicenter study.Methods56 patients (mean age 65.0 ± 8.7 years old) underwent bilateral implantation with multifocal Precizon Presbyopic IOL. The quality of vision was assessed by a quality of vision questionnaire at 6 months after the implantation procedure, a complete eye examination was also performed including visual and refractive measurements, defocus curve and contrast sensitivity assessment. Visual and refractive variables were compared in preoperative, 3-month postoperative and 6-month postoperative visits by Wilcoxon test.ResultsThe quality of vision analysis showed the absence of severe glare and severe haloes in all evaluated patients. Likewise, non-symptoms of glare, haloes and starbursts were seen in 75%, 68%, and 55% of subjects, respectively. Efficacy and safety index was 1.26 and 1.42, respectively. The 6-month postoperative binocular uncorrected distance visual acuity and near uncorrected visual acuity were 0.00 ± 0.09 and 0.20 ± 0.13 logMAR, respectively. Mean spherical equivalent was 0.29 ± 0.45 D.ConclusionsThe Precizon Presbyopic NVA IOL (OPHTEC BV) provides a suitable quality of vision with a low rate of disturbance photic phenomena induction, as well as an excellent visual performance at main distances of sight accomplishing the visual demands of the majority of patients.

Characteristics of posterior precortical vitreous pockets visualized by swept-source OCT and en face OCT

To determine the characteristics of posterior precortical vitreous pockets (PPVPs) and to observe vitreous changes in myopic eyes by swept-source optical coherence tomography (SS-OCT) and en face imaging in a cohort of the Chinese Han population. This was a cross-sectional study. Volunteers (235 participants, 374 eyes) received an SS-OCT examination. The heights and widths of the PPVPs were measured by SS-OCT. The area of the PPVPs was measured on en face images. The relationships between PPVP size and sex, age, axial length (AL) and spherical equivalent (SE) were evaluated. The mean width and height were 6711.64 ± 1241.87 μm and 662.47 ± 326.39 μm, respectively. The area of the PPVPs was 30.296 ± 9.114 mm2. Boat-shaped, oval, and hook-shaped PPVPs were observed in 73.26%, 21.12%, and 5.62% of all eyes, respectively; 73.53% of all PPVPs had channels communicating with Cloquet’s tubes. There was a significant difference in the PPVP width among the participates over and under 50 years old (t = -2.508, P = 0.031). Age had a positive correlation with the PPVP width (r = 0.53, P = 0.001). The PPVP height showed significant differences among the different myopia groups (F = 3.618, P = 0.013). SE had a negative correlation with the PPVP height (r = -0.176, P = 0.001). However, there were no correlations between the AL and the width, height or area of the PPVPs (P = 0.117; P = 0.334; P = 0.057, respectively). Age and myopia affect the size of PPVPs. SS-OCT greatly facilitates visualization of the complex structure of the vitreous.

Peripheral Iridectomy in Intrascleral Intraocular Lens Fixation: Preventing Reverse Pupillary Block

To compare clinical outcomes, reverse pupillary block (RPB) findings and anterior segment parameters in patients with and without intraoperative peripheral iridectomy during sutureless flattened flange intrascleral intraocular lens (IOL) fixation. Retrospective comparative case series. This study included 94 eyes of 82 patients who underwent IOL explantation due to vitreous-dislocated IOL at our clinic between March 2020 and September 2023, followed by flattened haptic-tipped IOL intrascleral fixation combined with pars plana vitrectomy (PPV). The patients were divided into two groups: Group 1 (n=54) underwent peripheral iridectomy during surgery, while Group 2 (n=40) did not undergo surgical peripheral iridectomy. Anterior chamber depth (ACD), anterior chamber angle (ACA) and white-to-white (WTW) distance were measured with Scheimpflug imaging. Visual outcomes, ACD, ACA, spherical equivalence (SE), intraocular pressure (IOP), complications, and secondary interventions were evaluated. There was no significant difference between the two groups preoperatively in terms of IOP, ACD, ACA, WTW distance, and axial length (p > 0.05). Postoperatively, the mean ACD was significantly less in Group 1 (3.79 ± 0.67 mm) than in Group 2 (4.11 ± 0.75 mm) (p = 0.03). Postoperative IOP was 15.51 ± 2.48 mmHg in group 1 and 18.20 ± 4.51 mmHg in group 2 (p < 0.001). The postoperative ACA was statistically significantly shallower in Group 1 (41.72 ± 3.47 degrees) than in Group 2 (52.45 ± 17.93 degrees) (p < 0.001). Postoperatively, RPB developed in 10 eyes (25.0%) in Group 2, while it was not observed in any patient in Group 1 (p < 0.001). In Group 2, pupillary capture developed in 4 cases (10%) in addition to RPB. Laser peripheral iridotomy was performed in cases with RPB. After laser peripheral iridotomy, mean IOP, mean ACA and ACD also decreased significantly (p < 0.001). Intraoperative peripheral iridectomy during scleral fixation surgery combined with PPV leads to significantly less RPB, a more stable anterior chamber, and fewer complications. Laser peripheral iridotomy was very useful in managing RPB that developed in the postoperative period.

Assessing the predictability of five intraocular lens calculation methods in eyes with prior myopic keratorefractive lenticule extraction.

To evaluate and compare the predictability of five methods of intraocular lens (IOL) calculation in eyes with prior keratorefractive lenticule extraction (KLEx) for the treatment of myopia. A retrospective case study included 100 eyes of 52 patients who underwent myopia and myopia with astigmatism treatment with small incision lenticule extraction (SMILE). Preoperative and 3-month postoperative measurements of optical biometry and corneal tomography were obtained. The spherical equivalent of the refractive change induced by surgery was converted to the corneal plane (SMILE-dif). A physically well-defined method was developed in which the same IOL model was implanted before and after SMILE. IOL power was calculated using ray-tracing (RT-Sirius), and several IOL power calculation formulas (Kane, EVO 2.0, Barrett Universal II Formula, Hoffer QST) before surgery. After surgery, IOL power was calculated with RT-Sirius, Kane using Mean Pupil Power at 5.5mm by ray tracing, EVO 2.0 Post Myopic LASIK/PRK, Barrett True K and Hoffer QST Post Myopic LASIK/PRK after surgery. The difference between the refractive error induced by the IOL before and after SMILE in the corneal plane (IOL-dif) was compared with SMILE-dif. The predicted error (PE) was calculated as the difference between SMILE-dif and IOL-dif. The PE obtained was 0.26 ± 0.55 diopters (D), 0.10 ± 0.45 D, 0.40 ± 0.37 D, -0.03 ± 0.36 D, 0.02 ± 0.51 D, with RT-Sirius, Kane, EVO 2.0, Barrett True K, and Hoffer QST respectively. PE was not statistically significantly different between Barrett True K and Hoffer QST, with differences being more homogeneous with Barrett, (variance σ2 = 0,13). The absolute EP obtained with Barrett True K achieved 84% of cases within ± 0.5 D, followed by Kane (72%), Hoffer QST (65%), EVO (61%) and RT-Sirius (59%). Barrett True K formula was the most accurate method for IOL calculation in eyes that had undergone SMILE for the correction of myopia. What is known The literature regarding IOL power calculation after SMILE is sparse, and the methods used to estimate corneal power following LASIK/PRK may not be applicable to SMILE procedures. The most common approach to investigating the predictability of IOL calculation formulas involves a theoretical model encompassing the virtual implantation of an IOL. What is new The Hoffer QST formula, Kane formula using Mean Pupil Power at 5.5mm, EVO 2.0, and Sirius' Ray Tracing software had not been previously evaluated using this approach. The Barrett True K formula was the most accurate method for IOL calculation in eyes that had undergone SMILE for myopia correction, outperforming Ray Tracing.

Regional/ethnic differences in ocular axial elongation and refractive error progression in myopic and non-myopic children.

To determine the regional and ethnic differences in ocular axial elongation and refractive error progression in myopic and non-myopic children. A retrospective analysis of 15 longitudinal clinical and population-based studies was conducted in the UK, Sweden, Australia (classified as European), China, and Vietnam (classified as East Asian) between 2005 and 2021. A total of 14,593 data points from 6208 participants aged 6-16 years with spherical equivalent from +6 to -6 D were analysed. Progression was annualised from longitudinal axial length and cycloplegic spherical equivalent (SE) refraction. Generalised estimating equation models including main effects and interactions were used for model building. Age and region-specific estimates for myopes and non-myopes and confidence intervals are reported. Factors affecting axial elongation and SE progression in children included being myopic, followed by age, region/ethnicity and sex. The magnitude of regional/ethnic differences was dependent on myopia and age. Axial elongation and SE progression were lower in European compared with East Asian children, but differences were reduced with increasing age and differences in axial elongation were larger in myopes than non-myopes. Age-specific regional/ethnic differences indicated that axial elongation for a 6-year-old East Asian myopic child was greater than a European child by 0.15 mm/year (0.58 vs. 0.43 mm/year) and by 0.09 mm/year (0.35 vs. 0.26 mm/year) for a 10-year-old myope. SE progression was lower in a 6-year-old European myope by 0.48 D/year and at 10 years of age by 0.34 D/year compared with an East Asian myope. There are regional/ethnic differences in age-specific refractive and axial growth patterns in both myopic and non-myopic eyes, with more marked differences in younger East Asian children who demonstrated a higher axial growth and greater negative SE shift than their non-Asian peers. Regional/ethnic differences in progression reflect environmental and ethnic variations. Age and region/ethnicity-specific estimates could contribute as a reference for future comparisons.

Evaluation of Corneal Biomechanics Using Brillouin Microscopy in Chinese Adults With Myopia.

To evaluate the corneal biomechanical metrics of Chinese adults with myopia and identify relevant factors of Brillouin microscopy. In this cross-sectional study, corneal biomechanics in Chinese adults with myopia were quantified and analyzed using Brillouin microscopy and the Corvis ST (CST) (Oculus Optikgeräte GmbH) and analyzed. Univariate linear regression was used with potential factors including age, sex, spherical equivalent (SE), intraocular pressure (IOP), central corneal thickness (CCT), and mean keratometry (Kmean). The study included 87 eyes of 87 participants (mean age: 24.47 ± 6.27 years). Central, Mean, maximum (Max), minimum (Min), standard deviation, and Max-Min Brillouin modulus (BM) values obtained from Brillouin microscopy exhibited values of 2.826 ± 0.039, 2.827 ± 0.027, 2.864 ± 0.034, 2.790 ± 0.038, 0.108 ± 0.042, and 0.074 ± 0.041 GPa, respectively. No significant correlations were found between BM parameters and age, sex, SE, IOP, or CCT. However, the Mean (β = -0.251, P = .019), Min (β = -0.315, P = .003), and Max-Min (β = 0.229, P = .033) BM values were significantly associated with Kmean. The Central, Mean, Min, and Max BM values negatively correlated with the Tomographic Biomechanical Index measured by CST (Spearman's r = -0.24, -0.35, -0.29, and -0.23, respectively, all P < .05). Brillouin microscopy accurately reflects corneal biomechanical parameters in Chinese adults with myopia, independent of IOP and CCT, with a good correlation with CST. Concurrent evaluation of the corneal curvature is imperative when employing Brillouin microscopy in clinical practice. [J Refract Surg. 2024;40(10):e768-e776.].

A 6-Month Follow-Up Comparative Study of Single-Step Transepithelial Photorefractive Keratectomy (Trans-PRK) Using the StreamLight Software with and without Epithelial Thickness Customization.

To compare corneal aberrometry, densitometry, and refractive outcomes of single-step Transepithelial Photorefractive Keratectomy (Trans-PRK) with and without epithelial thickness customization. This was a prospective, interventional, randomized controlled study. Patients undergoing Trans-PRK using the WaveLight EX500 laser with StreamLight software (Alcon Laboratories, Forth Worth, TX, USA) were randomly assigned to control (55µm standard epithelial thickness) or customized (thinnest point of epithelial thickness for each patient) groups. MS-39 (CSO, Italy) anterior segment optical coherence tomography was used to measure the epithelial thickness. Inclusion criteria were spherical equivalent <6 diopters (D), astigmatism <4D, and CDVA 20/25 or better. The assessments were at baseline and 6 months post-op: visual acuity, refraction, aberrometry, and corneal densitometry. 108 eyes were enrolled, [control group (n=56) and customized group (n=52)]. Mean epithelial ablation thickness in the customized group was 54.81±3.56µm (p=0.470 vs control group). Both groups experienced significant postoperative increases in higher-order aberrations (HOA) and spherical aberrations, with no significant intergroup differences. Mean HOA RMS (µm) of the frontal cornea and total cornea increased by 0.27, and 0.29, respectively, in the control group, and 0.26 and 0.28, respectively, in the customized group (p<0.001 for all). Mean change in spherical aberrations in the frontal cornea and total cornea was 0.23µm (p<0.001) and 0.25µm (p<0.001), in the control group, and 0.19µm (p<0.001) and 0.20µm (p<0.001), in the customized group. Mean corneal densitometry in anterior cornea decreased by 0.63GSU (p=0.021) and 1.18GSU (p<0.001) in the control and customized groups. In the posterior cornea, it increased by 1.67GSU (p=0.004) and 0.38GSU (p=0.006). No significant differences in refractive and aberrometry outcomes between control and customized Trans-PRK groups, with corneal densitometry changes not affecting visual acuity.

Visual Outcome and Patient Satisfaction with Implantation of Trifocal Intraocular Lens After Radial Keratotomy.

To investigate the visual outcomes and patient satisfaction following trifocal intraocular lens (IOL) implantation after radial keratotomy (RK). This was a retrospective chart review wherein we studied 14 eyes from 7 patients who had undergone cataract surgery and had trifocal intraocular lens (IOL) implanted in the Eastern Province of Saudi Arabia's King Fahd University Hospital and Kahhal private centre. Data such as demographic characteristics, the time between RK and cataract removal, intraoperative and postoperative complications, preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and refraction were evaluated. In addition, visual complaints and satisfaction were assessed through a questionnaire. All eyes included had 8 RK sections. The mean spherical equivalent was +1.81 ± 4.27 D preoperatively and was -0.41 ± 1.2 D at the last follow-up. The mean uncorrected distance visual acuity (UDVA) increased from 0.32 ± 0.2 prior to surgery to 0.64 ± 0.2 following surgery. The mean efficacy index was 1.01 and a safety index was 1.26. In the last follow-up, 29% reported having 0.5 spherical equivalents, while 86% were within 1D. Improvement in cylindrical correction was noticed in the last follow-up with 36% not more than 0.5 D and 43% within 1D. In total, 80% of patients had a distance-corrected near visual acuity (DCNVA) of better than 20/40. The survey response rate was 100%, and two patients reported a lower degree of satisfaction. Glare and difficulty seeing at night were the most often reported complaints, with a mean of 2.86 ± 1.95 and 22 ± 1.9, respectively. Our results suggest that implantation of a trifocal IOL is safe and effective in patients with previous RK. However, several factors, including the patient's preoperative expectations, glare testing, refractive error, number of cuts, optical zone size, and visual phenomena related to RK, should be considered before implantation.

Corneal Epithelial Remodeling Following Cylinder Correction With SMILE or FS-LASIK: A Contralateral Comparative Study.

To compare the corneal epithelial remodeling in eyes with high astigmatism that had small incision lenticule extraction (SMILE) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK). Seventy-four patients with myopic astigmatism of greater than -2.00 diopters (D) and little binocular difference in spherical equivalent were included in this contralateral comparative study. All patients received SMILE in one eye and FS-LASIK in the other eye randomly. The corneal epithelial remodeling pattern was mapped using the latest RTVue spectral-domain optical coherence tomographer (Optovue) by region. Satisfactory refractive correction was achieved in all enrolled eyes with either SMILE or FS-LASIK. The corneal epithelium gradually thickened following surgical cylinder correction, distributing mainly along the flat medium. The corneal epithelium proliferation is milder centrally but more pronounced in the mid-peripheral area after SMILE, compared with FS-LASIK. The flat-steep difference in corneal epithelial thickness (CET) is evident in the mid-peripheral and peripheral areas, which is more obvious in SMILE. Residual cylinder was positively correlated with CET in eyes that had FS-LASIK, but not SMILE. More importantly, these epithelial changes were positively correlated with the ablation depth and higher order aberrations following surgical refractive correction. The postoperative CET map varied between SMILE and FS-LASIK. In eyes with high astigmatism, SMILE surgery is followed by milder and more stable corneal epithelial thickening. Moreover, the corneal epithelium is sensitive to stromal ablation and corneal remodeling is crucial to the postoperative visual quality. This study rigorously distinguished the CET difference between SMILE and FS-LASIK in astigmatic eyes and shed light on subsequent research. [J Refract Surg. 2024;40(10);e728-e741.].

Intraoperative Aberrometry versus Preoperative Biometry for Intraocular Lens Power Calculations: A Report by the American Academy of Ophthalmology

To evaluate the published literature to compare intraoperative aberrometry (IA) with preoperative biometry-based formulas with respect to intraocular lens (IOL) power calculation accuracy for various clinical scenarios. Literature searches in the PubMed database conducted in August 2022, July 2023, and February 2024 identified 157, 18, and 6 citations, respectively. These were reviewed in abstract form, and 61 articles were selected for full-text review. Of these, 29 met the criteria for inclusion in this assessment. The panel methodologists assigned a level of evidence rating to each of the articles; 4 were rated level I, 19 were rated level II, and 6 were rated level III. Intraoperative aberrometry performed better than traditional vergence formulas, including the Haigis, HofferQ, Holladay, and SRK/T, and similarly to the Barrett Universal II and Hill-RBF with respect to minimization of spherical equivalent (SE) refractive error. For toric IOLs, IA outperformed formulas that only considered anterior corneal astigmatism and was similar to formulas like the Barrett Toric Calculator (BTC), which empirically account for the contribution from the posterior cornea. In eyes with a history of corneal refractive surgery, IA performed similarly to the Barrett True-K and slightly better than other tested methods, including the Haigis-L, Shammas, and Wang-Koch-Maloney formulas. Intraoperative aberrometry corresponds well with modern vergence formulas, including the Barrett Universal II, Hill-RBF, BTC, and Barrett True-K. It has greater accuracy than traditional vergence-based IOL power calculation formulas in eyes with and without a history of corneal refractive surgery. Proprietary or commercial disclosure may be found after the references.

Corneal Epithelial Remodeling After Hyperopic SMILE: A 4-Year Study.

The purpose of this study was to investigate dynamic changes in corneal epithelial thickness (ET) after hyperopic small incision lenticule extraction (SMILE). This observational study included 18 eyes of 16 patients who were scheduled for hyperopic SMILE. High-resolution spectral-domain optical coherence tomography and a custom image segmentation algorithm were applied to measure corneal dynamic ET over a central 6 mm area. ET was analyzed among different corneal sectors (central, pericentral, and peripheral) at baseline and multiple postoperative time points (1 day, 1 month, 6 months, 2 years, and 4 years). Correlation analysis was performed between ET changes and preoperative and intraoperative parameters. The mean spherical equivalent of hyperopia correction was +2.64 ± 1.00 D, and the average age of enrolled 16 patients was 32.4 ± 10.8 years. At the last follow-up, 72% of eyes kept or improved corrected distance visual acuity, with 2 eyes that lost 2 lines. 72% of eyes were within ±1.0 D of target refraction, and 56% were within ±0.5 D. Average ET decreased by 11.0% (5.9 ± 2.3 μm) from 53.2 ± 3.5 μm to 47.4 ± 4.2 μm 4 years postoperatively (P<0.001). The ET at center 2 mm decreased most significantly by 14.5% (7.9 ± 2.9 μm), followed by the pericentral area by 10.5% (5.6 ± 2.3 μm). ET and front corneal curvature stabilized 1 month after surgery. No correlation was found between refraction regression and ET changes. Hyperopic SMILE induced significant central ET thinning. ET remodeling in the 6 mm area stabilized after 1 month and did not underlie refractive changes.

Comparative study of visual and refractive outcomes of laser assisted in situ Keratomileusis versus small incision lenticule extraction versus implantable collamer lens for moderate to high myopia correction

Background Myopia represents a condition of refraction, in which parallel light rays converge in front of the resting eye retina. Aim To compare the laser assisted in situ keratomileusis (LASIK) visual and refractive outcomes versus small incision lenticule extraction (SMILE) versus implantable collamer lens (ICL) while correcting cases having moderate to high myopia. Patients and methods Our research involved 60 eyes having moderate to severe myopia ranging from –3 to –10 dioptres. They divided into three equal groups, group A: through LASIK, group B: through SMILE, and group C: received an ICL. Preoperative uncorrected visual acuity, Corrected distance visual acuity, and Manifest and cycloplgic refraction assessments were accomplished. Results Postoperative uncorrected visual acuity exhibited no significant variation among groups A and B, yet a significant variation was documented among groups A and C as well as among groups B and C P less than 0.001. The postoperative spherical error showed no significant variation among groups A and B nor among groups B and C yet exhibited significant variation among groups A and C P=0.002. Postoperative astigmatism was no significant variation among groups A as well as B, yet a significant variation was documented among groups A and C in addition to between groups B and C. Postoperative spherical equivalent was a significant variation among groups A and C P less than 0.001 and among groups B and C P less than 0.001. Conclusion Visual outcomes were comparable between LASIK, SMILE, and ICL. The three procedures exhibited superior effectiveness, safety, stability, and accuracy in the treatment of moderate and high myopia.

Relationship between dry eye disease and myopia: A systematic review and meta-analysis

Background/objectivesDry eye disease (DED) and myopia are common ocular disorders. This systematic review and meta-analysis investigated the association between DED and myopia. MethodsPubMed and EMBASE were searched for articles published between 1984 and 2022. Study quality was assessed using the Joanna Briggs Institute Critical Appraisal Checklist, and analysis was conducted using the DerSimonian–Laird random-effects model. ResultsOf the 1,313 studies identified, 15 studies on DED and myopia were included. The meta-analysis revealed that the overall prevalence of subjective DED symptoms in the myopia population was 45.1 % (95 % confidence interval: 0.287–0.616). There was a significant association between DED and myopia. The myopia population had higher Ocular Surface Disease Index scores and shorter tear film breakup times than the non-myopia population. Additionally, the meta-regression analysis showed that spherical equivalent was significantly associated with the prevalence of DED symptoms in adults with myopia. ConclusionInterventions to prevent DED are required in the myopia population. Enhancing patient awareness and self-management for DED, in addition to early screening and detection, is especially critical for younger populations who are at a higher risk of developing myopia.

The outcomes of first-generation (visumax 500) and second-generation (Visumax 800) keratorefractive lenticule extraction surgeries for astigmatism

To evaluate the efficiency, predictability, and residual astigmatism between first- and second-generation keratorefractive lenticule extraction (KLEx) surgeries in a prominent astigmatism population. A retrospective cohort study was conducted, and individuals who underwent first- and second-generation KLEx surgeries were enrolled. A total of 31 and 35 eyes were categorized into first and second KLEx groups, respectively. Visual acuity, refraction, topographic parameters, and surgical indices were recorded. Independent t tests were used to compare the postoperative uncorrected distance visual acuity (UDVA), spherical equivalent (SE), and residual astigmatism between the two groups. The difference in UDVA was not significant three months after KLEx surgery (P = 0.509), and the SEs three months after surgery also presented similar values between the two groups (P = 0.552). The first KLEx group demonstrated greater residual astigmatism than did the second KLEx group throughout the three-month follow-up period (all P < 0.05). The values of surgically induced astigmatism (SIA), difference vector (DV), magnitude of error (ME) and correction index (CoI) were significantly better in the second KLEx group via vector analysis (all P < 0.05). Old age, high steep keratometry (K), high topographic cylinder, large angle kappa, and a small optic zone were correlated with greater residual astigmatism in the first KLEx group (all P < 0.05), whereas only a small optic zone was significantly correlated with greater residual astigmatism in the second KLEx group (P = 0.047). The second-generation KLEx is correlated with a lower risk of residual astigmatism.

A Competition for the Diagnosis of Myopic Maculopathy by Artificial Intelligence Algorithms

Myopic maculopathy (MM) is a major cause of vision impairment globally. Artificial intelligence (AI) and deep learning (DL) algorithms for detecting MM from fundus images could potentially improve diagnosis and assist screening in a variety of health care settings. To evaluate DL algorithms for MM classification and segmentation and compare their performance with that of ophthalmologists. The Myopic Maculopathy Analysis Challenge (MMAC) was an international competition to develop automated solutions for 3 tasks: (1) MM classification, (2) segmentation of MM plus lesions, and (3) spherical equivalent (SE) prediction. Participants were provided 3 subdatasets containing 2306, 294, and 2003 fundus images, respectively, with which to build algorithms. A group of 5 ophthalmologists evaluated the same test sets for tasks 1 and 2 to ascertain performance. Results from model ensembles, which combined outcomes from multiple algorithms submitted by MMAC participants, were compared with each individual submitted algorithm. This study was conducted from March 1, 2023, to March 30, 2024, and data were analyzed from January 15, 2024, to March 30, 2024. DL algorithms submitted as part of the MMAC competition or ophthalmologist interpretation. MM classification was evaluated by quadratic-weighted κ (QWK), F1 score, sensitivity, and specificity. MM plus lesions segmentation was evaluated by dice similarity coefficient (DSC), and SE prediction was evaluated by R2 and mean absolute error (MAE). The 3 tasks were completed by 7, 4, and 4 teams, respectively. MM classification algorithms achieved a QWK range of 0.866 to 0.901, an F1 score range of 0.675 to 0.781, a sensitivity range of 0.667 to 0.778, and a specificity range of 0.931 to 0.945. MM plus lesions segmentation algorithms achieved a DSC range of 0.664 to 0.687 for lacquer cracks (LC), 0.579 to 0.673 for choroidal neovascularization, and 0.768 to 0.841 for Fuchs spot (FS). SE prediction algorithms achieved an R2 range of 0.791 to 0.874 and an MAE range of 0.708 to 0.943. Model ensemble results achieved the best performance compared to each submitted algorithms, and the model ensemble outperformed ophthalmologists at MM classification in sensitivity (0.801; 95% CI, 0.764-0.840 vs 0.727; 95% CI, 0.684-0.768; P = .006) and specificity (0.946; 95% CI, 0.939-0.954 vs 0.933; 95% CI, 0.925-0.941; P = .009), LC segmentation (DSC, 0.698; 95% CI, 0.649-0.745 vs DSC, 0.570; 95% CI, 0.515-0.625; P < .001), and FS segmentation (DSC, 0.863; 95% CI, 0.831-0.888 vs DSC, 0.790; 95% CI, 0.742-0.830; P < .001). In this diagnostic study, 15 AI models for MM classification and segmentation on a public dataset made available for the MMAC competition were validated and evaluated, with some models achieving better diagnostic performance than ophthalmologists.

Laser-Assisted In Situ Keratomileusis in Flat, Normal, and Steep Corneas.

To compare laser-assisted in situ keratomileusis (LASIK) outcomes in patients with different corneal curvatures. This is a retrospective comparative chart review. Patients included in this study underwent wavefront-optimized myopic LASIK between January 2013 and December 2022 at Care-Vision Laser Center, Tel-Aviv, Israel. Patients were divided into 3 groups based on the steepness of the cornea (steep keratometry) (flat: <42 diopters [D], normal: 42-46 D, and steep: >46 D). Case-by-case matching was performed to verify that baseline parameters (age, preoperative visual acuity, and refractive error) were similar between groups. Primary outcome measures were postoperative corrected/uncorrected distance visual acuity, efficacy index, safety index, spherical equivalence, and astigmatism. After matching, 300 eyes were included in each group, which were similar in baseline parameters. There were no significant postoperative differences between flat, normal, and steep corneas regarding safety index (1.01 vs. 1.02 vs. 1.01, P = 0.95), efficacy index (1.03 vs. 1.02 vs. 1.02, P = 0.94), logarithm of the minimum angle of resolution corrected distance visual acuity (0.01 vs. 0.01 vs. 0.01, P = 0.17), logarithm of the minimum angle of resolution uncorrected distance visual acuity (0.02 vs. 0.03 vs. 0.02, P = 0.65), proportion of patients with spherical equivalence within 0.50 D (73.0% vs. 73.7% vs. 69.3%, P = 0.45) or 1.00 D (93.3% vs. 94.7% vs. 91.7%, P = 0.34) of the target, and proportion of patients with astigmatism within 0.50 D (86.7% vs. 82.3% vs. 80.3%, P = 0.11) or 1.00 D (98.7% vs. 98.7% vs. 99.0%, P = 0.91) of the target. Longer term follow-up of a smaller set of patients revealed similar results. No significant differences were found between flat, normal, and steep corneas following wavefront-optimized myopic LASIK. Thus, this procedure may be safely and effectively performed across a wide range of corneal curvatures.

Clinical Outcomes of Iris-Supported Phakic Toric Intraocular Lenses in Corneal Ectasia.

Our aim was to evaluate the visual and refractive outcomes of iris-fixated phakic toric intraocular lenses (IOLs)for visual rehabilitation in eyes with stable corneal ectasia. We conducted a study looking at the clinical outcomes of iris-fixated toric IOLs (Artisan) in 33 eyes of 27 patients diagnosed with mild-to-moderate corneal ectasia at a single center (Queen Victoria Hospital, East Grinstead, UK). The main outcome measures were functional improvement [accuracy of post-operative spherical equivalent (SE), astigmatic correction, topographic parameters, uncorrected and corrected distance visual acuity (UCVA, CDVA)] and safety of the procedure: endothelial cell count and intra- and post-operative complications. Eighteen males and nine females of mean age 38.85 were included in the study with a mean follow-up of 18months. All patients had ectasia due to keratoconus except one with post-refractive laser ectasia. Twelve patients had crosslinking, eight had intracorneal rings, and eight had previous keratoplasties. Mean pre-operative logMAR UCVA was 0.75 ± 0.35 improving to 0.02 ± 0.17 (p = 0.000). Mean pre-operative logMAR CDVA was 0.16 ± 0.17 improving to 0.02 ± 0.17 (p = 0.000). Mean pre-operative (SE) was -3.5 ± 3.9 improving to -2.75 ± 1.39 (p = 0.000) with up to 36-42months of follow-up. The mean value of endothelial cell density in the overall sample was 2252.54 ± 473.24cells/mm2 pre-operatively and 2126.75 ± 365.21cells/mm2 at 24-36months of follow-up visit. Two patients have intra-operative hyphemia secondary to iris prolapse. Implantation of iris-fixated phakic toric IOLs has shown high efficacy and safety in patients with mild-to-moderate astigmatism in corneal ectasia.

Evaluation of Refraction Outcomes From the QuickSee Wavefront Autorefractor Versus Subjective Clinical Refractometry in Children With Restricted Access to Eye Care in Amazonas, Brazil.

Background This study compared the refraction measurements of the QuickSee wavefront autorefractor with those from clinical refraction measurements in preschool and elementary school children from public schools in Amazonas, Brazil. Methodology Refractometry was performed on 368 eyes from 368 healthy Brazilian public school students aged 4 to 7 years using both the QuickSee and subjective clinical methods under cycloplegia. Only right-eye data were analyzed. The results were converted into spherical equivalents and vector magnitudes for comparison. Results The difference in spherical equivalents between QuickSee and subjective clinical refractometry under cycloplegia was +0.38 ± 0.60 Diopters (D) (p < 0.0001). Along the 90° axis, the vector difference was +0.20 ± 0.33 D (p < 0.0001), and the oblique vector difference was +0.03 ± 0.22 D (p = 0.0395). Conclusions While a statistically significant difference was found between the QuickSee and subjective clinical refractometry results, the difference was not clinically meaningful. The strong agreement between these methods supports the utility of QuickSee as an effective tool for refractive assessment in children with limited access to eye care. These findings provide confidence in using QuickSee in public school settings as a reliable alternative for vision screening.