Spectacle-corrected Distance Visual Acuity Research Articles

Customized corneal allogenic intrastromal ring segments (CAIRS) for keratoconus with decentered asymmetric cone.

Corneal allogenic intrastromal ring segments (CAIRS) refer to the intracorneal placement of fresh, unprocessed, processed, preserved, or packaged allogenic rings/segments of any type/length. We described uniform-thickness CAIRS previously. We now describe a new technique of customized CAIRS to personalize the flattening effect as per individual topography. A prospective interventional case series of patients with pericentral/ paracentral decentered cones and gradation of keratometry with one side steeper than the other was conducted. Individually customized tapered CAIRS with variable volume, arc length, taper length, and gradient of taper were implanted. In total, 32 eyes of 29 patients with at least 1-year follow-up were included. Special double-bladed trephines and a CAIRS customizer template allowed the creation of individually customized CAIRS. Mean uncorrected distance visual acuity (UDVA) and spectacle-corrected distance visual acuity improved from 0.22 to 0.47 (P = 0.000) and from 0.76 to 0.89 (P = 0.001), respectively. Significant improvement was seen in K1, K2, Km, Kmax, topographic astigmatism, Q-value, sphere, cylinder, spherical equivalent, Root Mean Square (RMS), Higher Order Aberrations (HOA), and vertical coma (P < 0.01, 0.05). There was no significant change in the width or height of CAIRS between 1 month and last visit on anterior-segment optical coherence tomography. Five eyes continued to remain at the same UDVA, 27 eyes had at least 2 lines, and 13 eyes had at least 3 or more lines improvement in UDVA. The maximum improvement in UDVA was 7 lines. A significant difference in flattening was obtained at different zones across the tapered CAIRS. Thus, differential flattening was achieved across the cone based on the customization plan. Personalized customization was possible for each cornea, unlike limited models of progressive-thickness synthetic segments. Allogenic nature, greater customizability, efficacy, and absent need for large inventories are advantages compared to synthetic segments.

Development of a Web-Based Algorithm for Understanding the Intraocular Lens-Based Surgery in Stable and Progressing Keratoconus for Non-Specialist Ophthalmologists

Purpose To propose an algorithm to facilitate lens-based surgery in keratoconus. Methods A literature review was performed to prepare a software algorithm based on cone location, stability, best spectacle-corrected distance visual acuity (BSCVA) level and whether there is a clear or cataractous lens. The software usability was assessed through a 10-question questionnaire and two hypothetical keratoconus case histories (moderately simple and moderately complex) given to 15 trainees. The usability questionnaires were graded on a Likert scale (1 = strongly disagree to 5 = strongly agree) and two case histories (1 = very difficult to 7 = very easy). Results The algorithm can be found at https://www.sussexeyelaserclinic.co.uk/keratoconus/. Thirteen trainees completed the questionnaire. 91.9% would frequently use it; for 100%, it was easy to use independently without technical support; for 63.7%, it was strongly integrated; for 100%, it was consistent; 100% thought that most people would learn to use it quickly, 91.9% found the system not cumbersome to use, felt very confident to use it and need not learn a lot to use it. The first case was found easy by 63.7% and the second by 45%. Conclusion We present an algorithm as a guide for lens-based surgery in stable and progressing keratoconus, which is classified based on cone location. This algorithm will help trainee and “non-specialist” ophthalmic surgeons understand the pre-operative planning for the surgery and referral to the “specialist” corneal surgeon, considering factors such as progression, BSCVA, keratometry, topography and apex location of the cone in keratoconus patients.

Effects of Custom-Designed Soft Contact Lenses on Irregular Astigmatism Correction in Patients with Keratoconus.

To evaluate the efficacy of YOUSOFT soft contact lenses in correcting irregular astigmatism and prescription results of patients with keratoconus. The retrospective observational study included 55 eyes (mean age, 32.2 ± 10.6 years; 36 men and 6 women) of 42 patients with keratoconus who tried YOUSOFT for rigid gas permeable (RGP) lens intolerance. Average keratometry, corneal astigmatism, and maximum keratometry were 49.4 ± 5.2 diopters (D), 3.7 ± 2.1 D, and 57.3 ± 8.2 D, respectively. Patients were divided into YOUSOFT prescription and non-prescription cases, wherein the prescription rates were calculated. YOUSOFT visual acuity was compared with spectacle-corrected distance visual acuity (CDVA) and RGP lens-CDVA. YOUSOFT was prescribed to 28 out of 42 patients (prescription rate 67%). In the YOUSOFT prescription cases, YOUSOFT-CDVA (logMAR -0.04; 95% confidence interval [CI]: -0.08 to 0.00) was significantly better than spectacle-CDVA (logMAR 0.23; 95% CI: 0.08 to 0.38; P < 0.0001), whereas YOUSOFT-CDVA (logMAR -0.03; 95% CI: -0.08 to 0.03) did not significantly differ from the RGP lens-CDVA (logMAR -0.02; 95% CI: -0.08 to 0.04; P = 0.856). YOUSOFT was effective in correcting irregular corneal astigmatism, suggesting that it is highly effective in patients with RGP lens intolerance.

Rotational stability and refractive outcomes of the DFT/DATx15 toric, extended depth of focus intraocular lens

PurposeTo quantitatively assess postoperative rotational stability and visual acuity with the DFT/DATx15 extended depth of focus (EDOF) toric intraocular lens (IOL).MethodsIn this prospective case series, thirty-five patients with a calculated IOL power between + 15.0 D and + 25.0 D, corneal astigmatism between 0.75 D and 2.25 D, and no significant ocular pathology underwent cataract surgery. Primary outcome was rotational stability of the IOL at 1 month post-operatively. Secondary outcomes included residual refractive astigmatism, absolute residual astigmatism prediction error, and monocular distance and intermediate visual acuities.ResultsMean absolute postoperative IOL rotation was 1.1 ± 0.2 degrees, with no rotation of more than 3 degrees at the final visit. Monocular mean best spectacle-corrected distance visual acuity (BSCDVA) improved from logMAR 0.27 ± 0.030 to 0.078 ± 0.017 (P < .001). Monocular uncorrected distance visual acuity (UCDVA) improved from 0.93 ± 0.096 to 0.18 ± 0.022 (P < .001). Best spectacle-corrected intermediate visual acuity (DSCIVA) was 0.17 ± 0.025, and uncorrected intermediate visual acuity (UCIVA) was 0.27 ± 0.040. Residual regular astigmatic refractive error was 0.21 ± 0.047 D.ConclusionsThe toric DFT/DATx15 EDOF lens showed excellent rotational stability and effective and predictable correction of astigmatism. Its refractive outcomes and safety profile were similar to those identified in prior studies of the non-toric DFT/DAT015 EDOF IOL. A small difference in monocular BSCDVA, of uncertain clinical significance, was found when comparing these outcomes with prior DFT/DAT015 data. The trial was retrospectively registered on November 5, 2021 (TRN ​​NCT05119127).

Supracor Multifocal Corneal Laser-Assisted In Situ Keratomileusis Procedure for the Correction of Presbyopia in Hyperopic Eyes.

To investigate the outcomes of unilateral Supracor treatment to enhance near vision while maintaining good distance vision in hyperopic eyes. This prospective interventional study includes consecutive hyperopic patients with presbyopia. All eyes underwent femtosecond laser-assisted in situ keratomileusis treatment for hyperopia with an additional Supracor multifocal treatment algorithm in nondominant eyes. Monocular and binocular uncorrected and spectacle-corrected distance visual acuity (UCDVA and SCDVA), monocular and binocular uncorrected near visual acuity (UNVA), and distance-corrected near visual acuity at 40 cm and high-order aberration changes and complications were evaluated for 6 months. Sixty-four patients with a mean age of 51.91 ± 3.64 were enrolled. After 6-month follow-up, the mean binocular UCDVA and UNVA were 0.03 ± 0.05 and 0.04 ± 0.06 logMAR, respectively. UCDVA (logMAR) of nondominant and dominant eyes was 0.30 ± 0.18 and 0.03 ± 0.05, respectively. Preoperative and postoperative mean ± standard deviation manifest refraction spherical equivalent was +1.84 ± 0.75 and -0.48 ± 0.57, respectively, in nondominant eyes and +1.77 ± 0.69 and +0.12 ± 0.33, respectively, in dominant eyes. No complications were observed. Supracor procedure in nondominant eyes may improve functional near, intermediate, and distance vision without significant photic phenomena in presbyopic patients with low and moderate hyperopia.

Characterization and prediction of the clinical result with a specific model of mini-scleral contact lens in corneas with keratoconus

BackgroundTo investigate which factors are correlated with the visual improvement achieved with a specific model of scleral contact lens (SCL) in keratoconus (KC) eyes and to define a model to predict such improvement according to the pre-fitting data. In addition, the changes occurred with the fitting of a specific model of SCL during a period of 3 months in corneas with KC have been investigated.MethodsLongitudinal retrospective study including 30 eyes of 18 patients (age, 14–65 years) with KC fitted with the SCL ICD16.50 (Paragon Vision Sciences). Visual, refractive, corneal tomographic and ocular aberrometric changes were evaluated during a 3-month follow-up. Likewise, the characterization of the post-lens meniscus was performed by optical coherence tomography (OCT) with the measurement of central, nasal and temporal vaults.ResultsThe visual acuity increased significantly from a mean pre-fitting value with spectacles of 0.23 ± 0.07 logarithm of minimal angle of resolution (logMAR) to a mean value of 0.10 ± 0.04 logMAR after 1 month of SCL wear (P < 0.001). An improvement of 1 or more lines of visual acuity with the SCL occurred in 62.1% of the eyes. A significant decrease in central, nasal, and temporal vault was observed after 1 month of SCL wear (P ≤ 0.046). Likewise, there was a significant difference between nasal and temporal vaults during the first month of SCL use (P = 0.008). Furthermore, a significant reduction of ocular high order (P = 0.028) and primary coma root mean square (P = 0.018) was found with the SCL. A predicting linear equation of the change in visual acuity achievable with the SCL was obtained (P < 0.001, R2 = 0.878) considering the pre-fitting spectacle corrected distance visual acuity, and the power and sagittal lens of SCL.ConclusionsThe scleral contact lens evaluated provides an efficacious visual rehabilitation in KC due to the improvement of visual acuity and the correction of low and high-order ocular aberrations. This visual acuity improvement can be predicted from some pre-fitting variables.

Five-year results of a prospective, randomised, contralateral eye trial of corneal crosslinking for keratoconus.

Few studies have evaluated corneal crosslinking (CXL) in a prospective, randomised fashion. This study aimed to determine the efficacy and safety of CXL to reduce the progression of keratoconus. Prospective, unmasked, randomised, contralateral eye controlled trial at a tertiary eye centre. Individuals with bilateral progressive keratoconus. One eye from each subject was randomised to CXL and the contralateral, untreated eye acted as the control. change in maximum keratometry. uncorrected distance visual acuity, spectacle corrected distance visual acuity, spherical equivalent refraction, simulated keratometry, corneal astigmatism, minimum pachymetry and complications. Thirty-eight individuals (mean age 21.1 ± 6.7 years) were enrolled with one eye treated with CXL. At 5 years, there was a mean decrease in maximum keratometry of treated eyes (-1.45 ± 2.25 D) compared to an increase among the controls (1.71 ± 2.46 D; p < 0.001). There were significant differences between the treated and control groups in the mean change of Steep SimK (-1.07 ± 1.22 vs. 0.96 ± 1.97 D; p < 0.001), Flat SimK (-0.61 ± 1.34 vs. 0.43 ± 1.12 D; p < 0.001), corneal astigmatism (-0.45 ± 1.31 vs. 0.63 ± 1.52 D; p < 0.01) and minimum pachymetry (-32.49 ± 26.32 vs. -13.57 ± 24.11 μm; p < 0.01). Complications included sterile infiltrates (n=2), microbial keratitis (n=1), persistent corneal haze/scarring at 5 years (n=4) and loss of ≥2 lines of corrected distance visual acuity (n=3). CXL is an effective and relatively safe intervention to halt or reduce the progression of keratoconus in the majority of eyes for at least 5 years.

Long term results of accelerated corneal collagen cross-linking in pediatric keratoconus

To evaluate the long term visual, refractive, and corneal tomographic outcomes of epithelium-off accelerated corneal collagen cross-linking (ACXL) in the management of pediatric keratoconus (KC). This retrospective study included patients under 18 years old with progressive KC who underwent ACXL between 2012 and 2019 at Dicle University Hospital. Complete ophthalmic examination was performed including uncorrected distance visual acuity (UDVA), best spectacle-corrected distance visual acuity (CDVA), manifest refraction, and corneal tomography. Evaluations were performed preoperatively and at 6 months intervals postoperatively. Forty-nine eyes of 49 patients were included in the study. The mean age of patients at the time of ACXL was 14.2 ± 1.8 (range: 9.5-17.3) years. Mean follow up was 4.61 ± 1.90 (range: 2.0-8.1) years. The mean LogMAR UDVA improved from 0.94 ± 0.41 to 0.81 ± 0.43, 0.69 ± 0.41, and 0.67 ± 0.33 after 1, 3, and 5 years respectively (p = 0.001). The mean LogMAR CDVA improved from 0.58 ± 0.36 to 0.46 ± 0.31, 0.34 ± 0.23, and 0.39 ± 0.27 after 1, 3, and 5 years respectively (p = 0.015). The mean refractive cylinder improved significantly from 6.01 ± 2.07 diopters (D) to 5.46 ± 1.87, 5.38 ± 2.18, and 5.02 ± 2.31 D after 1, 3, and 5 years respectively (p = 0.005). As compared to preoperative values, steep keratometry and maximum keratometry were not significantly different (p = 0.805 and 0.448, respectively) following ACXL, while flat keratometry significantly improved after ACXL (p = 0.012). Although central corneal thicknesses decreased significantly (p = 0.029), the decrease in thinnest corneal thickness was not statistically significant (p = 0.205). Epithelium-off ACXL seems to be effective for halting KC progression with long term clinical benefits in pediatric patients.

The efficiency and safety of oxygen-supplemented accelerated transepithelial corneal cross-linking.

To investigate the impact of oxygen delivery on the clinical outcomes of accelerated transepithelial corneal cross-linking (A-TE CXL). Fifty-seven eyes of 44 progressive keratoconus (KCN) patients were randomly separated into two age-sex-matched groups. Twenty-nine eyes of 23 KCN patients that underwent oxygen-supplemented A-TE CXL formed the study group and 28 eyes of 21 patients treated with the same procedure but under room air conditions formed the control group. All patients were examined preoperatively, one, six and twelve months after the procedure. The logMAR spectacle-corrected distance visual acuity (CDVA), maximum keratometry (Kmax), mean keratometry, apical posterior keratometry, cylindrical power, minimum central corneal thickness, keratoconus vertex front and back, ocular aberrations, endothelial cell density (ECD), demarcation line depth (DLD) and proportion measures were recorded for statistical analysis. The preoperative, 1st, 6th and 12th months mean Kmax values of the study group were 55.14 ± 3.99D, 54.85 ± 3.82D, 54.37 ± 3.84D and 54.40 ± 3.86, respectively, and 54.47 ± 3.17D, 54.52 ± 2.97D, 54.25 ± 2.95D and 54.20 ± 2.97 in the control group. The mean Kmax value was decreased significantly more in the oxygen-supplemented group after 12months compared to the control group (p = 0.019). The mean DLD was also significantly deeper in the study group (320 ± 17µm) compared to the control group (269 ± 19µm). There was no significant difference between the two groups in terms of ECD alterations at any of the time intervals (p > 0.05). Keratoconus progression was significantly halted in both groups 12months after the treatment. In addition, oxygen supplementation during A-TE CXL further significantly increased clinical outcomes compared to room air conditions without any significant change in ECD measures.

Safety and efficacy of epithelial island crosslinking in keratoconus with thinnest pachymetry less than 400µ

PURPOSE:To evaluate the efficacy and safety of epithelial-island crosslinking (EI-CXL) in keratoconus with corneas thinner than 400 µm.METHODS:Twenty-six patients (30 eyes) underwent EI-CXL (preserving the epithelium over the thinnest area), using standard protocol (3 mW/cm2 for 30 min). Uncorrected and best spectacle-corrected distance visual acuity (UCDVA, BCDVA), manifest refractive spherical equivalent (SEQ), mean simulated keratometry (Kmean), maximum keratometry (Kmax), and thinnest corneal thickness (TCT) were determined preoperatively and at 1, 3, 6, and 12 months following CXL. Endothelial cell count (ECC) was determined preoperatively and at 6 months. Anterior segment optical coherence tomography (AS-OCT) was done at 1 month to determine the depth of the corneal stromal demarcation line (DL).RESULTS:After 1 year, mean UCDVA improved from 1.29 preoperatively to 1.17 (P = 0.001) and BCDVA from 0.62 to 0.57 (P = 0.011). Mean manifest SEQ decreased from -7.63 to-7.32D (P = 0.001). Mean Kmean decreased from 54.92 to 54.81D (P = 0.045), and Kmax from 67.60 to 67.42D (P = 0.072), and mean TCT changed minimally from 377.17 to 375.30 µ (P = 0.11). The mean ECC decreased from 2329 to 2268 cells/mm2 (2.6% decrease, P < 0.001). AS-OCT showed a DL in 29 out of 30 eyes at an average depth of 215.9 µ under the spared epithelium, and 299.9 µ in the de-epithelialized cornea.CONCLUSION:EI-CXL halted keratoconus progression over a 1-year period. This was associated with statistically significant endothelial loss, but less than seen with conventional epi-off CXL in thinner corneas.

Diagnostic Value of Corneal Epithelial and Stromal Thickness Distribution Profiles in Forme Fruste Keratoconus and Subclinical Keratoconus.

To assess the diagnostic values of corneal epithelial and stromal thickness distribution characteristics in forme fruste keratoconus (FFKC) and subclinical keratoconus (KC). This cross-sectional study was conducted at VISSUM Innovation and Miguel Hernandez University, Alicante, Spain. Twenty-seven eyes (27 subjects) with FFKC, 50 eyes (50 subjects) with subclinical KC with a best spectacle corrected distance visual acuity ≥20/20 (Snellen) (grade zero KC according to the Red Temática de Investigación Cooperativa en Salud classification), and 66 control eyes (66 subjects) were included. Epithelial and stromal thicknesses and epithelium/stroma (E/S) thickness ratio at center, thinnest point, 5-, and 8-mm circles obtained from the MS-39 device (CSO, Firenze, Italy) were compared among the control, FFKC, and subclinical KC groups. The FFKC group had thinner 8-mm superior-nasal epithelium and higher central E/S ratio compared with the control group (P < 0.05). In the subclinical KC group, the E/S ratios in the 5-mm temporal and superior zones were higher than those in the control group (P < 0.05). The FFKC and subclinical KC groups had thinner stroma compared with the control group (P < 0.05). A two-parameter formula correctly classified 94% of the eyes with subclinical KC and 98.5% of the normals, whereas another three-parameter model had 75% sensitivity and 94.3% specificity for discriminating FFKC from normals. This study identified different epithelial distributional and behavioral patterns in eyes with FFKC and subclinical KC. Eyes with FFKC seem to have increased central E/S ratio and asymmetric superior-nasal epithelial thinning, whereas keratometric and volumetric alterations seem to be more prominent in subclinical KC.

Pediatric versus Adult Corneal Collagen Crosslinking: Long-term Visual, Refractive, Tomographic and Aberrometric Outcomes

ABSTRACT Purpose To comparatively evaluate the long-term visual, refractive, topographic and aberrometric outcomes of conventional corneal collagen crosslinking (CXL) in the management of pediatric versus adult progressive keratoconus patients. Materials and Methods Retrospective, cross-sectional review of consecutive progressive keratoconus cases of corneal standard CXL using a standardized protocol for treatment and examinations was performed. Best spectacle-corrected distance visual acuity (CDVA), manifest refraction, slit lamp biomicroscopy, corneal tomography, corneal aberrometry and endothelial cell counts were evaluated at baseline and yearly at all postoperative follow-up examinations after month-12. The outcomes were analyzed by dividing the patients into 2 age groups; pediatric (≤18 years) versus adult (>18 years). Results Eighty-eight eyes (54 patients) in the pediatric and 104 eyes (68 patients) in the adult age groups completed 3 years follow-up. Compared to baseline, the mean CDVA, manifest refraction, keratometric readings, tomographic and aberrometric parameters improved statistically significantly in both groups at postoperative year-3 and year-4, without any statistically significant between-group differences. No change in the mean endothelial cell density (p > .05), or no sight threating complication was encountered in any patient eye in either group. In a subset of patients who were followed for 4 years (71 eyes in the pediatric and 70 eyes in the adult age groups), the outcome analyses were again similar between-groups. Conclusion Conventional corneal CXL effectively halts the progression of keratoconus in both pediatric and adult age groups in long-term follow-up with similar visual, refractive, tomographic and aberrometric efficacy in both groups.

Subclinical keratoconus detection with three-dimensional (3-D) morphogeometric and volumetric analysis.

To assess the efficacy of morphogeometric and volumetric characterization of the cornea based on three-dimensional (3-D) modelling in diagnosis of subclinical keratoconus (KC). Cross-sectional study. Ninety-three eyes with subclinical KC with a best spectacle-corrected distance visual acuity ≥20/20 (grade zero KC according to the RETICS classification) and 109 control eyes were included. Computer-based 3-D corneal morphogeometric model was generated using raw topographic data. Distance-, area- and volume-based parameters were used for statistical analysis. Distance parameters included deviation of anterior (Dapexant )/posterior (Dapexpost ) apices and minimum thickness points (Dmctant , Dmctpost ) from corneal vertex, and Dapexant -Dapexpost difference. Areal variables were derived from anterior (Aant ) and posterior (Apost ) corneal surfaces, sagittal plane passing through corneal apices (Aapexant , Aapexpost ) and thinnest point (Amctant , Amctpost ). Total corneal volume (Vtotal ) and volumetric distribution (with 0.1mm steps) centred to thinnest corneal point (VOLmct ) and anterior (VOLaap )/posterior (VOLpap ) apices comprised the volume-based parameters. In the subclinical KC group, all D values, Dapexant -Dapexpost difference, Aant , Apost and Aapexant values were higher (p<0.001), while Aapexpost , Amctpost , Vtotal , VOLmct , VOLaap and VOLpap values were lower when compared to the control group (p<0.001). Regression analysis-based formula correctly classified 96.8% of the eyes with subclinical KC and 94.5% of the normal ones (p<0.0001). Eyes with subclinical KC seem to represent asymmetrically displaced anterior and posterior corneal apex, corneal thinning and volume loss. 3-D morphogeometric and volumetric parameters and differentiation formula can be incorporated into topography software to detect subclinical KC with high sensitivity and specificity in clinical practice.

Objective Quantification of Image Quality and Optical Scatter Before and After Nd:YAG Capsulotomy Using a Double-Pass Technique.

PurposeThe purpose of this study is to evaluate and compare the correlation between changes in vision and HD Analyzer dual-pass metrics versus changes in vision and conventional subjective slit lamp gradings in pseudophakic patients with posterior capsular opacity undergoing neodymium:yttrium-aluminum-garnet (Nd:YAG) capsulotomy.Patients and MethodsHigh contrast (HC) and low contrast (LC) best spectacle-corrected distance visual acuity (BCVA) and HD Analyzer evaluation were prospectively performed on patients with mild-to-moderate posterior capsular opacification (PCO) and monofocal and accommodating intraocular lens implants. Differences between pre- and post-operative measurements were calculated, along with the correlation of HD Analyzer metrics and slit lamp grading to changes in visual acuity.ResultsFollowing Nd:YAG capsulotomy (n=29), there was statistically significant improvement in HC-BCVA and LC-BCVA, decrease in optical scatter, and corresponding improvement in Strehl ratio and HD Analyzer values at all contrast levels tested (p≤0.05). Pearson test showed a high correlation between the improvement in HC-BCVA (r coefficient = 0.78) and LC-BCVA (r coefficient = 0.71) to the improvement in Objective Scatter Index (OSI). There was a higher correlation of change in HC-BCVA to pre-op OSI (r2=0.61) than to the subjective PCO grading score (r2 = 0.19). There was also a higher correlation of change in LC-BCVA to pre-op OSI (r2 = 0.49) than to subjective grading (r2 = 0.16).ConclusionThe HD Analyzer provides objective measurements of forward light scatter (ie, light directed towards the retina) that can assist with both PCO grading and prediction of improvement of visual quality after YAG laser capsulotomy with higher accuracy than conventional slit lamp assessment based upon backscatter (ie, light traveling to the observer) in patients tested with monofocal and accommodating intraocular lens implants.

Corneal wavefront-guided versus aberration-free transepithelial photorefractive keratectomy in patients with myopia with high pre-existing corneal higher order aberrations

Objective The aim was to compare the efficacy, safety, and predictability of corneal wavefront-guided (WFG) and aberration-free ablation in single-step transepithelial photorefractive keratectomy (TransPRK) in patients with myopia with high pre-existing corneal higher order aberrations (HOAs). Background Corneal WFG and aberration-free treatments have been proposed as methods to achieve better visual, refractive, and optical outcomes. Patients and methods A prospective case series was conducted in El-Hekma Eye-LASIK Center, Menoufia Governorate, Egypt, during the period from January 2017 to December 2017. TransPRK was performed for eligible patients with myopia with or without astigmatism with corneal HOAs greater than or equal to 0.35 μm using either aberration-free or corneal WFG patterns provided by ORK-CAM software. Uncorrected distance visual acuity, manifest and cycloplegic refractions, best spectacle corrected distance visual acuity, thorough slit lamp examination, and corneal topography were assessed and repeated 6 months postoperatively. Results Six months postoperatively, 97.6 and 100% of patients achieved manifest refraction spherical equivalent within ±1 D and 76.2 and 66.67% of patients achieved uncorrected distance visual acuity of greater than or equal to 20/20 in aberration-free and corneal WFG groups, respectively. Both groups showed increase in spherical and total corneal HOAs, with no significant difference in corneal WFG (P = 0.08 and 0.28, respectively), though significantly higher postoperatively in aberration-free group (P Conclusion Both aberration-free and corneal WFG TransPRK were safe, effective, and predictable in treatment of myopia in patients with high pre-existing corneal HOAs with better aberrometric outcomes in corneal WFG group.

Corneal Surface Ablation Laser Refractive Surgery for the Correction of Myopia: A Network Meta-analysis.

To systematically compare the efficacy, predictability, safety, postoperative haze, pain scores, and epithelial healing time of four corneal surface ablation procedures. PubMed, Embase, Cochrane Library, and the U.S. trial registry were searched up to June 2018. Randomized controlled trials were selected. Efficacy (uncorrected distance visual acuity of 20/20 or better), predictability (refractive spherical equivalent within ±0.50 diopters [D] of the target), and safety (loss of two or more lines of spectacle corrected distance visual acuity) were set as primary outcome measures. Haze, pain scores, and epithelial healing time were set as secondary outcome measures. Eighteen studies involving 1,423 eyes were included. According to the Grading of Recommendations Assessment, Development, and Evaluation, the quality of outcomes were moderate to high (70.6%). There were no differences in efficacy, predictability, safety, haze, day 1 pain, and epithelial healing time between treatments. Epithelial laser in situ keratomileusis (epi-LASIK) had statistically significantly higher pain scores on day 3 compared to photorefractive keratectomy (PRK) (weighted mean differences [WMD] = 2.2, 95% credible intervals [CrI] = 0.19 to 4.01) and transepithelial PRK (T-PRK) (WMD = 2.7, 95% CrI = 0.51 to 4.84). The surface under the cumulative ranking curve ranking results (best to worst) showed laser epithelial keratomileusis (LASEK) ranked highest for efficacy, predictability, safety, and day 1 pain scores. Epi-LASIK ranked best for grade 1 haze scores. T-PRK ranked best for haze of 0.5 or higher, haze scores day 3 pain scores, and epithelial healing time. Surface laser refractive surgeries are comparable in terms of efficacy, predictability, safety, and postoperative haze except for day 3 pain scores, with epi-LASIK being more painful compared to PRK and T-PRK. [J Refract Surg. 2018;34(11):726-735.].

Long-Term Results of Femtosecond Laser-Enabled Keratoplasty With Zig-Zag Trephination.

To report long-term visual and astigmatism outcomes in cases of zig-zag femtosecond laser-enabled penetrating keratoplasty (FLEK). Retrospective review. Three hundred thirty-five eyes of 287 patients underwent (FLEK) with a zig-zag incision pattern. Patients were assessed preoperatively and underwent postoperative comprehensive examinations at standard intervals of 1, 3, 6, 9, and 12 months, and 6 months thereafter. Postoperative uncorrected distance visual acuity and spectacle-corrected distance visual acuity and manifest and topographical (Mrx cyl and Topo cyl) astigmatism were compared with preoperative values. Three hundred thirty-five eyes received FLEK with zig-zag configuration. Data are presented for the last recorded visit before any refractive procedure. Sutures were removed in 202 of 335 eyes at an average time to removal of 1.3 ± 1.1 years, and a mean follow-up period of 2.9 ± 2.1 years (range 0-10 years). After full suture removal, mean uncorrected distance visual acuity and spectacle-corrected distance visual acuity were logarithm of the minimum angle of resolution 0.84 (Snellen 20/138) ± 0.55 and 0.33 (Snellen 20/42) ± 0.33, respectively. Mean Mrx cyl and Topo cyl of these groups were 3.38 ± 2.22 and 4.77 ± 3.15, respectively. Of the total number of grafts, the rate of graft rejections was 14.0%, and the failure rate was 5.6%. The femtosecond laser-generated zig-zag-shaped incision results in lower manifest and topographical astigmatism than the reported average for conventional penetrating keratoplasty. Graft rejection and failure rates are similar to published data for conventional penetrating keratoplasty.

Corneal Cross-Linking in Pediatric Patients: Evaluating Treated and Untreated Eyes-5-Year Follow-Up Results.

To evaluate the long-term results of corneal collagen cross-linking (CXL) for treatment of pediatric keratoconus and the long-term outcomes of the fellow untreated keratoconic eye in patients younger than 18 years old. A retrospective case analysis was performed on 88 eyes of 44 patients aged 18 years or younger, with keratoconus, who underwent CXL in at least 1 eye. Follow-up measurements, for the treated and untreated eye pair, taken up to 5 years after treatment, were compared with baseline values. Parameters included uncorrected distance visual acuity (UCDVA), best spectacle-corrected distance visual acuity (BCDVA), manifest refraction, pachymetry, and corneal topography and tomography. Mean age of patients was 15.6 ± 2.1 years. For the treated eyes, during all years of follow-up, UCDVA improved significantly (from 0.83 ± 0.30 to 0.72 ± 0.28 logMAR; P = 0.01). Improvement in BCDVA was not statistically significant (from 0.28 ± 0.19 to 0.23 ± 0.15 logMAR; P = 0.06). The manifest cylinder showed a significant reduction (from 5.8 ± 3.6 to 4.3 ± 2.5 diopters; P = 0.006). There was no significant change in maximum keratometry. Average keratometry and corneal thickness reduced significantly (P = 0.009 and P = 0.002, respectively). Five patients had very mild corneal haze after CXL. For the fellow untreated eyes-during 5 years of follow-up, UCDVA showed a slight decrease that was not statistically significant. BCDVA, average keratometry, and maximum keratometry remained stable. Our long-term follow-up study suggests that CXL is a safe procedure in the pediatric age, and there is no urgency in treating pediatric patients with keratoconus without proof of progression.

Binocular benefits of optical treatment in anisometropic amblyopia.

In this study, we investigated the effect of optical treatment on sensory eye balance in anisometropic amblyopia. Fourteen individuals (age: 13.7 ± 8.4 years old) with previously untreated anisometropic amblyopia were enrolled in the study. The average magnitude of their anisometropia (spherical equivalent) was 4.02 ± 1.19 DS. Their best corrected monocular visual acuity and sensory eye balance were measured before and after a 2-month period of full refractive correction (i.e., our optical treatment). Spectacle-corrected distance visual acuity (at 5 m) was measured monocularly using the Tumbling E Chart. Sensory eye balance was quantitatively assessed using a binocular phase-combination paradigm to determine the interocular contrast ratio at which the two eyes were balanced in binocular sensory combination (i.e., the balance point). We found that both interocular contrast ratio at the balance point (p = 0.006) and visual acuity of the amblyopic eye (p < 0.001) were significantly improved after 2 months of optical treatment, often referred to as refractive adaptation. We conclude that sustained optical treatment improves interocular sensory balance in anisometropic amblyopia as well as monocular acuity. Optical treatment is a passive form of binocular therapy and a necessary first step in treating the binocular dysfunction that characterizes amblyopia.

Avoiding big bubble complications: outcomes of layer-by-layer deep anterior lamellar keratoplasty in children

Background/aimsTo describe the visual and clinical outcomes of manual layer-by-layer deep anterior lamellar keratoplasty (DALK) in a paediatric population.MethodsThe charts of all children who underwent DALK surgery between January 2007...