Corneal Higher-order Aberrations Research Articles

Characterization of postoperative LASIK ectasia features on higher-order aberration excimer ablation maps

BackgroundTo characterize anterior corneal higher-order aberration (HOA) excimer ablation map patterns in postoperative LASIK ectasia (POE) and to examine correlations between newly identified corneal HOA ablation map features of POE and known topographic indices.MethodsProspective multicenter non-interventional descriptive study. A total of 28 eyes from 22 POE patients were enrolled. The postoperative HOA ablation map was derived from Topolyzer Vario corneal imaging at the time of POE diagnosis. Features that recurred were identified and then analyzed. Correlations to Orbscan indices were studied.ResultsAn arrangement of two elliptical paracentral ablation islands, deep inferior and shallow superior, in direct mirror-like opposition to each other, were identified on all HOA maps. The paracentral islands were accompanied by peripheral ablation crescents. The deep paracentral inferior island ‘hot spot’ coincided with the topographical apical POE cone and was highly reproducible in angular position (249.3 ± 17.3°). There was significant variation in ablation depth (shallow superior island: 11.5 ± 6.9 μm and deep inferior island: 32.5 ± 18.8 μm). The superior crescents had high variability in depth (34.8 ± 18.9 μm). Strong correlations were found between the corneal irregularity index and the ablation depth difference between the deep and shallow paracentral islands (R = 0.96; P < 0.0001).ConclusionThe corneal HOA excimer ablation map revealed a recurring, distinct, easily recognizable pattern in POE eyes. Validated Orbscan POE indices and HOA ablation map islands showed a strong correlation. It is possible to extract useful information from the corneal HOA ablation map, potentially making it suitable for diagnosing and monitoring POE although more studies are needed.

Symmetrical femtosecond laser arc incision in correcting corneal astigmatism in cataract patients.

To evaluate the effect of symmetrical arc incision correcting corneal astigmatism in femtosecond laser-assisted phacoemulsification (FLACS). This study enrolled patients with cataract combined with regular corneal astigmatism of >0.75 D, who underwent FLACS. Symmetrical arc incision was set at 8 mm diameter and 85% depth. The follow-up time was 3-24mo (4.92±3.49mo). Pentacam recorded the corneal astigmatism and higher-order aberration at pre-operation and post-operation. The changes in corneal astigmatism were analyzed by Alpins method. The correlation of astigmatism type, age, corneal horizontal diameter, corneal thickness, arc incision length, and correction index (CI) was analyzed, and the residual corneal astigmatism was compared with the residual whole eye astigmatism. Totally 79 patients (102 eyes) were enrolled, 10 patients had corneal epithelial injury, 1 patient occurred corneal epithelial hyperplasia. The corneal astigmatism was 1.23±0.38 D pre-operation, and decreased to 0.76±0.39 D post-operation (t=10.146, P=0.000). Corneal high-order aberration was 0.17±0.08 µm pre-operation and 0.24±0.11 µm post-operation (t=-5.186, P=0.000). The residual corneal astigmatism and residual whole eye astigmatism were no significant difference (t=-0.347, P=0.729). Using Alpin's method, the following were determined: target-induced astigmatism (TIA) =1.23±0.38 D, surgery-induced astigmatism (SIA) =0.77±0.45 D, difference vector (DV)=0.77±0.39 D, and CI=0.54±0.28. Age, astigmatism size, corneal horizontal diameter, corneal thickness, and arc incision length were not correlated with CI. The CI for against the rule astigmatism (ATR) was better than that for with the rule astigmatism (WTR; P=0.001). Femtosecond laser-assisted astigmatic keratotomy has better CI of ATR, but increase higher-order corneal aberration. CI is not ideal, it's not a perfect choice if we pursue ideal correction effect.

Comparison of Corneal Higher-order Aberrations Measured by Scheimpflug Camera and Placido Disc-based Topography in Korean Patients

Purpose: We compared corneal higher-order aberration (HOA) measurements between the Pentacam&lt;sup&gt;®&lt;/sup&gt; HR (PC), which uses the Scheimpflug principle, and the iTrace&lt;sup&gt;TM&lt;/sup&gt; aberrometer (IT), which evaluates Placido disc topography.Methods: We retrospectively analyzed 109 eyes of 87 patients without a history of ocular surface disease during the period from January 2021 to December 2022; both devices were used on the same day. We calculated the root mean square values (μm) of corneal total HOA and of the corneal 3rd- and 4th-order HOA at a pupil diameter of 4 mm. Data were compared by Bland-Altman plots for agreement analysis and Pearson correlation coefficient for correlation analysis.Results: There was no significant difference in the total HOA (&lt;i&gt;p&lt;/i&gt; = 0.145), coma (&lt;i&gt;p&lt;/i&gt; = 0.309), or secondary astigmatism (&lt;i&gt;p&lt;/i&gt; = 0.080) between the PC and IT measurements; all other HOAs significantly differed between devices (&lt;i&gt;p&lt;/i&gt; &lt; 0.001). In the correlation analysis, the total HOA (r = 0.605, &lt;i&gt;p&lt;/i&gt; &lt; 0.001) and coma (r = 0.634, &lt;i&gt;p&lt;/i&gt; &lt; 0.001) were moderately correlated between the two devices; the other HOAs showed low degree of correlations. In the Bland-Altman plot analysis, all HOAs showed low agreement between the two devices.Conclusions: Corneal total HOA and coma measured by the two devices were significantly correlated between the two devices, but other HOAs showed significant differences in measurement and low correlations. Therefore, corneal HOA measurements cannot be interpreted interchangeably between the two devices.

Clinical outcomes of stromal lenticule rotation to correct mixed astigmatism.

To describe a stromal lenticule rotation surgical technique to correct mixed astigmatism and evaluate the initial clinical outcomes of this innovative approach. This retrospective case series included five eyes from five patients with mixed astigmatism that underwent intrastromal lenticule rotation surgery. The eyes were evaluated for uncorrected visual acuity, corrected distance visual acuity, manifest refraction, central corneal thickness, corneal volume, anterior and posterior K readings, and corneal higher order aberrations (HOAs) (including total HOAs, spherical aberrations, coma, and trefoil) using the Scheimpflug-Placido topographer before and 3 months after surgery. The corneal epithelium and stroma were imaged using anterior segment optical coherence tomography (AS-OCT) postoperatively. A paired-sample t-test was used to analyse the data. Clinical improvement was found in the uncorrected distance visual acuity (0.64 ± 0.11 logMAR vs. 0.20 ± 0.17 logMAR) and spherical and cylindrical diopters (D) (+2.65 ± 1.32 D vs. -0.05 ± 0.51 D and -4.95 ± 0.94 D vs. -1.10 ± 0.78 D, respectively). Anterior flat keratometry readings showed a steep trend (40.65 ± 1.24 D vs. 42.73 ± 0.63 D). Anterior corneal astigmatism decreased from 4.50 ± 0.55 D to 2.05 ± 0.73 D. According to the AS-OCT images, no significant epithelial remodelling was observed postoperatively. Although no significant differences were found among the increased corneal HOAs, the coma and trefoil changed much more than spherical aberrations 3 months postoperatively. The results for these five eyes suggest that the autologous stromal lenticule rotation technique is safe and effective; it may be an economical and feasible surgical option for correcting mixed astigmatism.

Evaluation of Corneal High Order Aberrations in Post Laser-Assisted in Situ Keratomileusis versus Photorefractive Keratectomy in Myope

Background Aberrations of the eye are the difference between two surfaces: the ideal and the actual wave front. Higher order aberrations are a relatively small component, comprising about 10% of the eye’s total aberrations. High order aberrations increase with age and minor symmetry exists between the right and the left eyes. Aim and objectives To Compare corneal high order aberrations in post laser-assisted in situ keratomileusis with corneal high order aberrations in post Photorefractive keratectomy in myope. Subjects and methods this study was designed as a prospective randomized intervention study that conducted on 40 myopic eyes. The eyes divided into two randomized groups. Group A: 20 myopic eyes corrected with laser-assisted in situ keratomileusis and Group B: 20 myopic eyes corrected with Photorefractive keratectomy. Cases were collected for LASIK and PRK at operative theater in Beni-Suef University Hospital and clear vision laser center in Cairo, from May 2019 till January 2022. Result There was clinically significant difference between pre- and post-operative visual acuity, vertical trefoil and vertical coma of LASIK group and there was clinically significant between pre- and post-operative visual acuity, vertical trefoil and vertical coma of PRK group. But there was no significant difference between LASIK and PRK in visual acuity, spherical aberration, higher order 5 mm and 6 mm, vertical coma and Vertical trefoil. Conclusion There is non-significant increase in higher order aberration and spherical aberration post LASIK and post PRK with lesser amount in PRK.

Corneal Higher Order Aberrations and Epithelial Remodeling With Femtosecond Laser-Assisted LASIK Topography-guided and Customized Asphericity Ablation in the Contralateral Eye: A Randomized, Double-Blind, Prospective Study.

To evaluate refractive results, corneal higher order aberrations (HOAs), and epithelial remodeling in the preoperative and postoperative period of regular corneas that had topography-guided femtosecond laser-assisted laser in situ keratomileusis (LASIK) (Contoura WaveLight; Alcon Laboratories, Inc) and compare them with the contralateral eye that underwent ablation customized by asphericity (Custom-Q WaveLight; Alcon Laboratories, Inc) in myopic eyes with or without astigmatism. A prospective, randomized, and double-blind study was conducted. Patients underwent preoperative and postoperative epithelial mapping and corneal tomography to assess the epithelial thickness map, HOAs of the corneal anterior surface, visual acuity, and refractive evaluation. This study enrolled 96 normal eyes of 48 patients. Uncorrected distance visual acuity of 20/20 or better was achieved in 97% of patients and gains in corrected distance visual acuity and effectiveness in correcting refractive astigmatism were similar in both techniques. Seventeen sectors of the corneal epithelium map were assessed by spectral-domain optical coherence tomography and no significant differences were found between techniques preoperatively and postoperatively (P > .05). HOA root mean square, coma Z3±1, trefoil Z3-3, and tissue consumption exhibited statistically significant between-technique differences (P < .05). The Contoura and Custom-Q techniques were similar with respect to refractive and visual outcomes after 3 months, as well as in epithelial remodeling. The Contoura provides lower postoperative HOA root mean square, coma Z3±1, and trefoil Z3-3 values, but the techniques showed no differences in the correction of the corneal astigmatic wavefront component and in the spherical aberration after 3 months. [J Refract Surg. 2023;39(11):751-758.].

Simultaneous Topography-guided Custom Ablation With Corneal Cross-linking for Keratoconus: 10-Year Prospective Outcomes

Purpose: To assess 10-year visual and tomographic outcomes of topography-guided custom ablation (T-CAT) with corneal cross-linking (CXL) in eyes with keratoconus. Methods: T-CAT with CXL was performed in 600 eyes (522 patients). Based on the T-CAT ablation plan, the theoretical maximum ablation depth was 50 µm after epithelium removal. After ablation, accelerated corneal cross-linking (CXL) was performed in the central 8-mm zone (9 mW/cm 2 for 10 minutes in “epi-off” mode). The visual acuity and tomography were assessed. Results: There was significant improvement in uncorrected ( P = .001) and corrected ( P = .001) distance visual acuity after the procedure. Keratometry, root mean square lower order aberrations and higher order aberrations, defocus, coma 90°, and spherical aberration reduced significantly after surgery at 10 years of follow-up ( P &lt; .005). All Pentacam (Oculus Optikgerate GmbH) tomographic variables showed significant changes indicating regularization after T-CAT ( P &lt; .005). Flattening of greater than 5.00 diopters in maximum keratometry was noted in 6 eyes (1%). Two of 600 eyes progressed postoperatively and required repeat CXL. Conclusions: T-CAT plus CXL is a safe and effective technique even in the long term for regularizing the anterior corneal surface with significant visual improvement and reduction in higher order corneal aberrations. [ J Refract Surg . 2023;39(11):759–766.]

The association between ocular biometric components and corneal aberrations

ABSTRACT Clinical relevance Evaluating factors affecting corneal higher-order aberration component has a very important role in interpreting the characteristics of the formed image on the retina. Background To determine the relationship between ocular biometric components and corneal higher-order aberrations in an elderly population. Methods This report is related to a subsample of the Tehran Geriatric Eye study (TGES), a population-based cross-sectional study that was conducted on individuals aged 60 years and above in Tehran city, Iran using multistage stratified random cluster sampling. All study participants underwent ocular examinations including visual acuity measurement, refraction and slit-lamp biomicroscopy. Anterior segment imaging and corneal aberrometry were performed using Pentacam AXL. Results In the present study, 644 eyes of 415 individuals (56.9% female) with mean age of 66.36 ± 4.70 years were evaluated. According to a multiple generalised estimating equation model, the root mean square of total higher-order aberrations was related to age (β = 0.081, p = 0.002), crystalline lens thickness (β = 0.08, p < 0.001), and corneal diameter (β = -0.04, p = 0.014). The root mean square of total coma aberration was directly related to the female sex (β = 0.02, p = 0.05), and crystalline lens thickness (β = 0.06, p < 0.001). There was a direct relationship between the root mean square of third- and fourth-order higher-order aberrations and crystalline lens thickness (p < 0.001). Spherical aberration was directly related to the male sex (β = -0.02, p = 0.004), axial length (β = 0.05, p < 0.001) and central corneal thickness (β = 0.001, p = 0.025), and was inversely related to anterior chamber depth (β = -0.07, p = 0.031) and crystalline lens thickness (β = -0.25, p < 0.001). Conclusion Ocular biometric components are related to corneal aberrations in the elderly. These factors need to be considered in respect of medical and surgical procedures required for the elderly.

Association between Corneal Higher-Order Aberrations Evaluated with a Videokeratographer and Corneal Surface Abnormalities in Dry Eye.

Analysis of higher-order aberrations (HOAs) is one reported method for evaluating dry eye disease (DED)-related loss of visual function. Tear film (TF) instability and corneal epithelial damage (CED) are both reportedly responsible for HOAs in DED, although, to the best of our knowledge, there are no reported methods that allow concurrent evaluation of their effects. In this study, we used a videokeratographer (VK) to continuously measure HOAs in DED after eye opening and investigated factors of ocular surface abnormalities that determine HOAs. This study involved 96 DED cases that underwent DED symptom assessment with a questionnaire and examination of tear volume, TF abnormalities (i.e., TF lipid-layer interference grades and spreading grades, and non-invasive breakup time and fluorescein breakup time), and CED, and their correlation with HOAs evaluated via VK. The results show that HOAs at 1 or 2 s after eye opening can reflect TF instability and CED within the central 4-millimeter-diameter area of the optical zone in DED eyes concurrently. This finding may be useful for the rapid and non-invasive detection and evaluation of degraded visual function in DED cases with a variety of clinical features.

Short term clinical observation of keratoconus treated with stromal lenticule addition keratoplasty combined with corneal collagen cross-linking

Objective: To investigate the efficacy of Femtosecond laser-assisted stromal lenticule addition keratoplasty (SLAK) combined with corneal collagen cross-linking (CXL) in the treatment of middle and advanced Keratoconus. Methods: It was a retrospective case series study. Data of 23 cases (24 eyes) of keratoconus treated with femtosecond laser-assisted SLAK combined with CXL in Laser Vision Centre of Xi'an No.1 Hospital from September 2020 to June 2022 were collected, including 16 males and 7 females, aged (23.69±5.18) years. The thickness, diopter number and diameter of the donor corneal stromal lens were assessed. uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), and diopter were recorded before and 1, 3, and 6 months after surgery. Sirius 3D fault corneal topography instrument to measure flat simulated keratometry (Kf), steep simulated keratometry (Ks) and the difference between them (ΔK), as well as central corneal thickness (CCT) and corneal high-order aberration. Results: Six months after surgery, CCT (454.83±50.01) μm were significantly higher than before (384.92±35.45) μm (P<0.05). Six months after surgery, UCVA (1.41±0.32) was significantly lower than before (1.11±0.33)(P<0.05). Six months after surgery, spherical diopter [(-15.73±7.89) D], Kf [(56.82±4.76) D] and Ks [(61.00±4.70) D] were significantly higher than before [(-12.08±5.99) D, (53.55±4.95) D, (58.65±5.10) D] (P<0.05). There was no significant difference in BCVA, column mirror degree and higher order aberrations before and 6 months after surgery(P>0.05). No corneal stromal lens folds, melting and displacement were observed in all eyes during the follow-up period, and no corneal opacity or immune rejection was observed. Conclusions: femtosecond laser-assisted SLAK combined with CXL can significantly increase the corneal thickness of keratoconus and has good effectiveness. In addition, six months of postoperative follow-up of patients showed no significant changes in BCVA and high-order aberrations in the 6 mm central diameter of the cornea, and no postoperative adverse reaction were found in all eyes, indicating that the operation has certain safety.

Rate of fractional change in corneal tomography parameters in keratoconus using a combination of predictive parameters

BackgroundTo compare the rate of fractional change for multiple corneal tomographic factors in progressive keratoconus (KC).MethodsIn this retrospective case series, 40 eyes (40 patients) with progressive KC (increase in central keratometry of 1.00 D or maximum keratometry of 1.50 D on two visits at least six months apart) were included. Cases with previous history of ocular surgery, poor scans, corneal scars, severe dry eyes, post-excimer ectasia, pellucid marginal degeneration were excluded. Medical records, corneal tomography and anterior corneal wavefront (8 mm) (Scheimpflug tomography, Pentacam, Oculus, Germany) were analyzed. Rate of fractional change (Rx = (x1 − x0)/(|x0|tm)); where, x1 = value at follow-up, x0 = value at initial visit and tm = time in months, was measured.ResultsThe mean age of the patients was 30.0 ± 8.4 years. The mean follow-up duration was 8.9 ± 4.2 months. Coma (0.076 ± 1.4) had the largest rate of fractional change (P = 1.7 × 10−14, Kruskal–Wallis test). The rate of fractional change was higher for aberrometric parameters (anterior corneal higher-order aberrations root mean square and anterior coma) compared to pachymetric and keratometric parameters (P values ranging from 1.4 × 10−4 to 7.4 × 10−10, Mann–Whitney test, effect size ranging from 0.4–0.7). The rate of fractional change was comparable between pachymetric and keratometric factors (P > 0.05 for all comparisons, Mann–Whitney test).ConclusionsAnterior corneal wavefront, especially anterior coma, were noted to have higher rate of fractional change compared to single point keratometric and pachymetric indices in progressive KC. This information can be used for decision-making when monitoring patients with KC.

A Comprehensive Wavefront Assessment of Keratoconus Using an Integrated Scheimpflug Corneal Tomographer/Hartmann-Shack Wavefront Aberrometer.

To characterize higher-order aberrations (HOAs) in different severities of keratoconus (KC) from the anterior and posterior corneal surfaces and whole eye using an integrated Scheimpflug corneal tomographer/Hartmann-Shack wavefront aberrometer. This study included eyes with clinical KC, topographic KC (no clinical signs), fellow eyes with very asymmetric ectasia with normal topography and no clinical signs (VAE-NT), and control eyes. Corneal and ocular wavefront aberrations were obtained using an integrated Scheimpflug tomographer/Hartmann-Shack wavefront aberrometer. The diagnostic capability of distinguishing VAE-NT from the control was also tested. This study included 68 eyes with clinical KC, 44 with topographic KC, 26 with VAE-NT, and 45 controls. Clinical KC had significantly greater total HOAs and coma from the anterior and posterior corneal surfaces and whole eye than the other groups ( P <0.05). Although topographic KC had significantly greater values in all wavefront parameters than the control ( P <0.05), ocular and corneal HOAs did not differ between the VAE-NT and control groups. The coma from the anterior cornea in topographic KC was significantly greater than that in VAE-NT ( P <0.05); the coma from the posterior cornea and whole eye did not differ. Total HOAs from the anterior corneal surface exhibited the highest area under the receiver operating characteristic curve value of 0.774 (sensitivity, 73%; specificity, 78%). A comprehensive wavefront assessment can be used to quantitatively evaluate corneal and ocular HOAs across various severity of KC. Total HOAs from the anterior corneal surface exhibited the potential ability in distinguishing VAE-NT from the control eyes.

A Prospective Study of Cyclosporine A 0.1% Combined with Loteprednol 0.2% vs Cyclosporine A 0.05% Alone in the Treatment of Dry Eye.

To examine the efficacy and tolerability of a combination of cyclosporine 0.1% and loteprednol 0.2% (CsA-LE; Klarity CL) in comparison to commercially available cyclosporine 0.05% (CsA; Restasis) in improving signs and symptoms of dry eye. This multicenter, prospective, randomized, controlled, open-label study evaluated 60 patients randomized to a single treatment for 4 weeks and evaluated at day 0, day 14, and day 28. Comparison was made of corneal higher-order aberrations (HOAs), dry-eye symptoms (SPEED score), tear-breakup time (TBUT), corneal staining, and ocular hyperemia, as well as tolerability of each medication with the validated COMTOL instrument. A total of 56 patients completed enrollment. Corneal HOAs improved significantly with CsA-LE, but not CsA alone. Both groups showed significant improvement (with no significant differences between groups) in SPEED scores, corneal staining, TBUT, and conjunctival hyperemia. Tolerability was similar between the drugs, and no significant safety issues were identified. The combination of CsA 0.1%-LE 0.2% provided significant improvement in corneal HOAs, while CsA 0.05% did not. For all other measures of ocular surface improvement, both medications showed similar benefits. Tolerability was comparable between the formulations. When rapid rehabilitation of the ocular surface is needed to reduce aberrations, CsA-LE is an appropriate choice.

Comparison of visual quality after SMILE correction of low-to-moderate myopia in different optical zones

ObjectiveTo compare the effects of different optical zones for small-incision lenticule extraction (SMILE) on postoperative visual quality in low-to-moderate myopia.MethodsThis retrospective case–control study involved patients who underwent SMILE using two optical-zone diameters: 6.5 mm (50 patients, 100 eyes) and 6.8 mm (50 patients, 100 eyes). Uncorrected visual acuity (UCVA), best corrected visual acuity, spherical equivalent (SE), corneal higher-order aberrations (HOAs), and subjective visual-quality questionnaire scores were assessed.ResultsPostoperatively, UCVA and SE did not differ between the two groups (P > 0.05). In both groups, corneal HOAs, spherical aberration, and coma significantly increased at 1 and 3 months postoperatively (P < 0.05), while trefoil was unchanged after surgery (P > 0.05). Corneal HOAs, spherical aberration, and coma significantly differed between the groups at 1 and 3 months (P < 0.05), while trefoil did not (P > 0.05). Visual-quality scores were higher in the 6.8 mm group than in the 6.5 mm group at 1 month (P = 0.058), but not at 3 months (P > 0.05). In both groups, subjective scores significantly decreased at 1 month (P < 0.05) and gradually returned to the preoperative level at 3 months (P > 0.05). The subjective visual-quality scores were negatively and positively correlated with pupillary and optical-zone diameter, respectively (P < 0.05 for both). Objective visual-quality indicators (HOAs, spherical aberration, and coma) were negatively correlated with optical-zone diameter (P < 0.05) but not pupillary diameter (P > 0.05).ConclusionSMILE in different optical zones effectively corrected low-to-moderate myopia. The larger the optical-zone diameter, the better the early postoperative visual quality.

Comparison of visual performance between bifocal and extended-depth-of-focus intraocular lenses.

We compared the visual performance of a bifocal intraocular lens (IOL) (ZMB00) and an extended-depth-of-focus (EDOF) IOL (ZXR00V) by evaluating postoperative parameters at 10 weeks after the last surgery in cataract patients who underwent bilateral ZMB00 or ZXR00V implantation between 2011 and 2020. The right and left lenses were implanted within 3 months of each other. The study enrolled 1536 eyes of 768 patients; the ZMB00 group comprised 1326 eyes of 663 patients (age: 67.0 ± 7.8 years; female/male, 518/145), and the ZXR00V group comprised 210 eyes of 105 patients (age: 67.8 ± 6.9 years; female/male, 39/66). A linear mixed-effects model using data for both eyes, with strict adjustments for sex, age, subjective refraction spherical equivalent, subjective refraction cylinder, corneal astigmatism, axial length, corneal higher-order aberrations and pupil diameter, ensured statistical validity. Uncorrected near visual acuity, corrected near visual acuity, and near spectacle independence were significantly better in the ZMB00 group (p<0.00068, Wald test) than in the ZXR00V group. Contrast sensitivity (visual angle of the test target: 4.0°/2.5°/1.6°/1.0°/0.7°) and contrast sensitivity with glare (4.0°/2.5°/1.6°/1.0°/0.7°) were significantly better in the ZXR00V group (p<0.00068, Wald test) than in the ZMB00 group. Uncorrected intermediate visual acuity, contrast sensitivity with glare (6.3°), and 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) scores for General Vision were slightly but significantly better in the ZXR00V group than in the ZMB00 group (p<0.05, Wald test). At high-performance levels, the two IOL groups had different characteristics regarding various visual performance parameters.

Characteristics and influencing factors of corneal higher-order aberrations in patients with cataract

PurposeTo observe the distribution characteristics of corneal higher-order aberrations (HOAs) in cataract patients, and analyze the relationship of HOAs with patients’ age and ocular biometric parameters.MethodsThis retrospective study reviews the patients with cataract in Wuhan Aier Eye Department from January to August 2022. Root mean square (RMS) of the total HOA (tHOA), spherical aberration (SA), coma and trefoil aberration of the anterior cornea at central 4 and 6 mm optic zone were measured by the Wavefront Aberrometer (OPD-Scan III; Nidek Inc, Tokyo, Japan). The biometric parameters including axial length (AL), keratometry (K), central corneal thickness (CCT) and lens thickness (LT) were measured by swept-source coherence laser interferometry (OA-2000; TOMEY Corp, Aichi, Japan). Subgroup analyses and multiple linear regression analyses were used to determine whether HOAs were associated with age and ocular biometric parameters.ResultsA total of 976 patients (976 eyes) were included, averagely aged 65 years. At central 4 and 6 mm optic zone, the mean RMS of tHOA were respectively 0.20 and 0.65 μm, the SA were 0.06 and 0.30 μm, the coma aberration were 0.11 and 0.35 μm, and the trefoil aberration were 0.12 and 0.30 μm. The tHOA decreased with age until 60 years and then started to increase afterwards. The tHOA, coma and trefoil aberration increased with corneal astigmatism. The tHOA, SA, and coma aberration differ among different AL groups, and emmetropes had the smallest tHOA, SA, and coma aberration.ConclusionsWith increasing age, the value of tHOA decrease first and started increasing at 60 years. The trends of corneal HOAs are consistent with corneal low-order aberrations. The values of tHOA, SA and coma aberration were the smallest in emmetropic eyes.

Effect of preoperative pupil offset on corneal higher-order aberrations after femtosecond laser-assisted in situ keratomileusis

BackgroundThis study aimed to investigate the relationship between multiple higher-order aberrations (HOAs) subgroups and pupil offset, as well as to analyze the factors affecting postoperative corneal HOAs in patients with different degrees of refractive errors.MethodsWe enrolled 160 patients (316 eyes) aged ≥ 18 years who had undergone femtosecond laser-assisted in situ keratomileusis (FS-LASIK) treatment. Based on the relationship between the preoperative pupil offset and the postoperative ΔHOAs, all patients were divided into two groups: group I (pupil offset ≤ 0.20 mm) and group II (pupil offset > 0.20 mm). All of the eyes had low to high myopia with or without astigmatism (manifest refraction spherical equivalent (MRSE) < -10.00 D). Uncorrected distance visual acuity, corrected distance visual acuity, MRSE, pupil offset, central corneal thickness, corneal HOAs, vertical coma (Z3−1), horizontal coma (Z31), spherical aberration (Z40), trefoil 0° (Z33), and trefoil 30° (Z3−3) over a 6 mm diameter central corneal zone diameter were evaluated preoperatively and at 1 and 3 months postoperatively.ResultsOur result revealed significant differences in postoperative corneal total root mean square (RMS) HOAs, RMS vertical coma, RMS horizontal coma, RMS spherical aberration, and RMS trefoil 30° between group I and group II. ΔMRSE was found to be an effective factor for ΔRMS HOAs (R2 = 0.383), ΔRMS horizontal coma (R2 = 0.205), and ΔRMS spherical aberration (R2 = 0.397). In group II, multiple linear regression analysis revealed a significant correlation between preoperative pupillary offset and Δtotal RMS HOAs (R2 = 0.461), ΔRMS horizontal coma (R2 = 0.040), and ΔRMS trefoil 30°(R2 = 0.089). The ΔRMS vertical coma effect factor is the Y-component, and the factor influencing ΔRMS spherical aberration was ΔMRSE (R2 = 0.256).ConclusionA small pupil offset was associated with a lower induction of postoperative corneal HOAs. Efforts to optimize centration are critical for improving surgical outcomes in patients with FS-LASIK.

Changes in corneal high order aberrations and anterior chamber parameters following scleral fixated intraocular lens implantation

BackgroundTo evaluate the change in corneal high order aberrations (HOAs) and anterior chamber parameters following scleral fixation in aphakic patients using the Scheimpflug camera system. MethodsThis retrospective study included patients who were aphakic after phacoemulsification surgery and underwent scleral-fixed intraocular lens (SF-IOL) implantation with Z suture technique between 2010 and 2022. Preoperative and postoperative best corrected visual acuity (BCVA), anterior segment parameters and corneal aberrations were evaluated with a combined Scheimpflug-Placido disk corneal topography device (Sirius Costruzione Strumenti Oftalmici, Florence, Italy). The following values were recorded: Simulated keratometry (SimK), flat meridian (K1), steep meridian (K2), iridocorneal angle (ICA), temporal anterior chamber angle (T-ACA), nasal anterior chamber angle (N-ACA), horizontal anterior chamber diameter (HACD), anterior chamber volume (ACV), corneal volume (CV), total Root Mean Square (RMS), high order aberrations (HOAs), spherical aberration, coma, trefoil, quadrifoil, and secondary astigmatism. ResultsThe study included 31 eyes of 31 patients (mean age: 63.00 ± 19.41 years, 17 males/14 females). Postoperative BCVA was better than preoperative BCVA (p = 0.012). Postoperatively, there was a statistically significant increase in ACV and CV values and a statistically significant decrease in K2 (p = 0.009, p = 0.032, p = 0.015). Preoperative T-ACA and preoperative and postoperative ACV were negatively correlated with postoperative intraocular pressure (r=-0.427 p = 0.033, r=-0.406 p = 0.032 and r=-0.561 p = 0.001). There were statistically significant postoperative increases in corneal RMS, trefoil and HOAs for 3 mm pupil diameter (p = 0.0177, p = 0.001, p = 0.031) and in corneal RMS, trefoil and quadrifoil aberrations for 6 mm pupil diameter (p = 0.033, p = 0.001, p = 0.001). ConclusionsIn conclusion, SF-IOL implantation with Z-suture technique used for visual rehabilitation of aphakic patients may affect visual quality by increasing corneal HOAs while improving visual acuity.

Erratum to: Effect of Upper Lid Blepharoplasty Surgery on Corneal Topography and Corneal High-Order Aberrations.

Correction to: Effect of Upper Lid Blepharoplasty Surgery on Corneal Topography and Corneal High-Order AberrationsFacial Plast Surg eFirstDOI: 10.1055/a-2047-7405

Higher-order aberrations and visual quality after incision lenticule extraction surgery with intraoperative angle kappa adjustments between small and large kappa patients: A 2-year follow-up.

To evaluate the postoperative visual outcomes, that is, corneal higher-order aberrations (HOAs) and visual quality, of patients with an angle kappa greater than 0.30 mm who underwent angle kappa adjustment during small-incision lenticule extraction (SMILE) 2 years after surgery compared to eyes with an angle kappa less than 0.30 mm. This was a retrospective study and included 12 patients from October 2019 to December 2019 who underwent the SMILE procedure for correction of myopia and myopic astigmatism and had one eye with a large kappa angle and another eye with a small kappa angle. Twenty-four months after surgery, an optical quality analysis system (OQAS II; Visiometrics, Terrassa, Spain) was used to measure the modulation transfer function cutoff frequency (MTFcutoff), Strehl2D ratio, and objective scatter index (OSI). HOAs were measured with a Tracey iTrace Visual Function Analyzer (Tracey version 6.1.0; Tracey Technologies, Houston, TX, USA). Assessment of subjective visual quality was achieved using the quality of vision (QOV) questionnaire. At 24 months postoperatively, the mean spherical equivalent (SE) refraction was - 0.32 ± 0.40 and - 0.31 ± 0.35 in the S-kappa group (kappa <0.3 mm) and the L-kappa group (kappa ≥0.3 mm), respectively (P > 0.05). The mean OSI was 0.73 ± 0.32 and 0.81 ± 0.47, respectively (P > 0.05). There was no significant difference in MTFcutoff and Strehl2D ratio between the two groups (P > 0.05). Total HOA, coma, spherical, trefoil, and secondary astigmatism were not significantly different (P > 0.05) between the two groups. Adjustment of angle kappa during SMILE helps reduce the decentration, results in less HOAs, and promotes visual quality. It provides a reliable method to optimize the treatment concentration in SMILE.