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Cataract or refractive lens surgery, along with the implantation of multifocal intraocular lenses (MF-IOL), enables a complete range of functional far, near and intermediate vision. Refractive, diffractive and extended depth of focus (EDoF) or combination of these principles represent the technology used to obtain this multifocality. Aberrometry makes it possible to study the aberrations induced by MF-IOLs. Among the different optical principles available to measure ocular aberrations, pyramidal wavefront-based sensor (PWS) aberrometry shows the highest resolution with MF-IOLs. Retinal image quality measured by a PWS aberrometer differed significantly according to the technology of the implanted lens. Monofocal and diffractive lenses showed the highest values of far-distance retinal image quality, followed by refractive and EDoF lenses; however, retinal image quality analysed in diffractive lenses appears to be more dependent on residual refractive error. Considering this limitation, PWS-aberrometry could be used to compare diffractive lenses. Nevertheless, further studies are needed to provide additional information about the clinical retinal image quality of MF-IOLs and to help surgeons in the important preoperative selection of IOLs.

This study aims to evaluate the applicability of the high-resolution WaveFront Phase Imaging Sensor (WFPI) in eyes with Fuchs’ Endothelial Corneal Dystrophy (FECD) through qualitative and quantitative analysis using a custom-designed Automatic Guttae Detection Method (AGDM). The ocular phase was measured using the t · eyede aberrometer and then was processed to obtain its High-Pass Filter Map (HPFM). The subjects were pathological and healthy patients from the Fundación Jiménez-Díaz Hospital (Madrid, Spain). The AGDM was developed and applied in pupils with 3 and 5 mm of diameter. A set of metrics were extracted and evaluated like the Root-Mean-Square error (RMS), Number of guttae, Guttae Area, and Area of Delaunay Triangulation (DT). Finally, a Support Vector Machine (SVM) model was trained to classify between pathological and healthy eyes. Quantitatively, the HPFM reveals a dark spots pattern according to the ophthalmologist’s description of the slit-lamp examination of guttae distribution. There were significant statistical differences in all the metrics when FECD and Healthy groups were compared using the same pupil size; but comparing both pupil sizes for the same group there were significant differences in most of the variables. This sensor is a value tool to objectively diagnose and monitor this pathology through wavefront phase changes.

To evaluate and compare the performance of two diffractive trifocal and one extended depth of focus (EDOF) intraocular lenses (IOLs). In this 6-month, single-center, prospective, randomized, comparative study, patients undergoing routine cataract surgery were randomized to receive one of two trifocal IOLs (AcrySof IQ PanOptix; Alcon Laboratories, Inc., Fort Worth, TX, or FineVision Micro F; PhysIOL SA, Liège, Belgium) or an EDOF IOL (TECNIS Symfony; Abbott Medical Optics, Inc., Abbott Park, IL). There were 20 patients in each group. The primary outcome was binocular and monocular uncorrected distance (UDVA), intermediate (UIVA), and near (UNVA) visual acuity. The secondary outcomes were quality of vision and aberrometry. There was no statistically significant difference between groups in either monocular (P = .717) or binocular (P = .837) UDVA. Monocular and binocular UNVA were statistically and significantly better for both trifocal lenses than for the EDOF IOL (P = .002). The percentage of patients with J2 UNVA was 52.5% monocularly and 70% binocularly for the TECNIS Symfony IOL, 81.5% monocularly and 100% binocularly for the AcrySof IQ PanOptix IOL, and 82.5% monocularly and 95% binocularly for the FineVision Micro F IOL. There was no significant difference in binocular UIVA between groups; VA was better than 0.6 in 55%, 53%, and 35% of patients with the TECNIS Symfony, AcrySof IQ Pan-Optix, and FineVision Micro F IOLs, respectively. Overall, 90% patients achieved spectacle independence. There were no differences in visual symptoms and aberrometry among groups. All three IOLs provided good visual acuity at all distances, a high percentage of spectacle independence, and little or no impact of visual symptoms on the patients' daily functioning. Near vision was statistically better for both trifocal IOLs compared to the EDOF IOL. [J Refract Surg. 2018;34(8):507-514.].

Background Refraction is one of the key components of a comprehensive eye examination. Auto refractometers that are reliable and affordable can be beneficial, especially in a low-resource community setting. The study aimed to validate the accuracy of a novel wave-front aberrometry-based auto refractometer, Instaref R20 against the open-field system and subjective refraction in an adult population. Methods All the participants underwent a comprehensive eye examination including objective refraction, subjective acceptance, anterior and posterior segment evaluation. Refraction was performed without cycloplegia using WAM5500 open-field auto refractometer (OFAR) and Instaref R20, the study device. Agreement between both methods was evaluated using Bland-Altman analysis. The repeatability of the device based on three measurements in a subgroup of 40 adults was assessed. Results The refractive error was measured in 132 participants (mean age,30.53 ± 9.36 years, 58.3% female). The paired mean difference of the refraction values of the study device against OFAR was − 0.13D for M, − 0.0002D (J0) and − 0.13D (J45) and against subjective refraction (SR) was − 0.09D (M), 0.06 (J0) and 0.03D (J45). The device agreed within +/− 0.50D of OFAR in 78% of eyes for M, 79% for J0 and 78% for J45. The device agreed within +/− 0.5D of SR values for M (84%), J0 (86%) and J45 (89%). Conclusion This study found a good agreement between the measurements obtained with the portable autorefractor against open-field refractometer and SR values. It has a potential application in population-based community vision screening programs for refractive error correction without the need for highly trained personnel.

Purpose: Barrett toric calculator (BTC) is known for its accuracy in toric IOL (tIOL) calculation over standard calculators; however, there is no study in literature to compare it with real-time intraoperative aberrometry (IA). The aim was to compare the accuracy of BTC and IA in predicting refractive outcomes in tIOL implantation. Methods: This was an institution-based prospective, observational study. Patients undergoing routine phacoemulsification with tIOL implantation were enrolled. Biometry was obtained from Lenstar-LS 900 and IOL power calculated using online BTC; however, IOL was implanted as per IA (Optiwave Refractive Analysis, ORA, Alcon) recommendation. Postoperative refractive astigmatism (RA) and spherical equivalent (SE) were recorded at one month, and respective prediction errors (PEs) were calculated using predicted refractive outcomes for both methods. The primary outcome measure was a comparison between mean PE with IA and BTC, and secondary outcome measures were uncorrected distance visual acuity (UCDVA), postoperative RA, and SE at one month. SPSS Version-21 was used; P < 0.05 considered significant. Results: Thirty eyes of 29 patients were included. Mean arithmetic and mean absolute PEs for RA were comparable between BTC (−0.70 ± 0.35D; 0.70 ± 0.34D) and IA (0.77 ± 0.32D; 0.80 ± 0.39D) (P = 0.09 and 0.09, respectively). Mean arithmetic PE for residual SE was significantly lower for BTC (-0.14 ± 0.32D) than IA (0.001 ± 0.33D) (−0.14 ± 0.32D; P = 0.002); however, there was no difference between respective mean absolute PEs (0.27 ± 0.21 D; 0.27 ± 0.18; P = 0.80). At one-month, mean UCDVA, RA, and SE were 0.09 ± 0.10D, -0.57 ± 0.26D, and -0.18 ± 0.27D, respectively. Conclusion: Both IA and BTC give reliable and comparable refractive results for tIOL implantation.

To compare the refractive prediction accuracy of the Optiwave Refractive Analysis (ORA) SYSTEM with the Barrett True-K (BTK) formula in calculating intraocular lens (IOL) power in eyes that underwent cataract surgery after previous myopic photorefractive keratectomy (PRK) or laser-assisted in situ keratomileusis (LASIK). This retrospective study evaluated patients aged ≥22 years with prior myopic PRK or LASIK who underwent unilateral or bilateral cataract removal and monofocal IOL implantation using the ORA SYSTEM at 177 sites in the United States. Two datasets were analyzed: All Eyes (ie, all eligible eyes) and First Surgery Eyes (ie, each patient's first implanted eye). All Eyes were subgrouped by axial length (AL) and further analyzed. The main outcomes included paired differences in absolute prediction errors (APEs) between the ORA SYSTEM and BTK and differences in the proportion of eyes with APEs of ≤0.25 diopter (D) and ≤0.50 D. 1067 eyes were analyzed, including 897 First Surgery Eyes. Significantly higher proportions of All Eyes had APEs of ≤0.25 D ( = 0.0128) and ≤0.50 D ( < 0.0001) using the ORA SYSTEM than the BTK formula. Similarly, significantly higher proportions of First Surgery Eyes had APEs of ≤0.25 D ( = 0.0037) and ≤0.50 D ( = 0.0004) using the ORA SYSTEM than the BTK formula. In both datasets, mean ( < 0.0001) and median ( ≤0.0005) APEs were significantly lower with the ORA SYSTEM than with the BTK formula. AL did not affect the differences in prediction accuracy between these IOL power calculations. In post-myopic PRK or LASIK eyes undergoing cataract surgery, the ORA SYSTEM provided significantly more accurate refractive predictability than the BTK formula, as determined by mean and median APE.

Purpose: This study was conducted to evaluate the accuracy of intraoperative aberrometry (IA) in intraocular lens (IOL) power calculation and compare it with conventional IOL formulas. Methods: This was a prospective case series. Eyes with visually significant cataract and axial hyperopia (AL <22.0 mm) underwent IA-assisted phacoemulsification with posterior chamber IOL (Alcon AcrySof IQ). Postoperative spherical equivalent (SE) was compared with predicted SE to calculate the outcomes with different formulas (SRK/T, Hoffer Q, Haigis, Holladay 2, Barrett Universal II and Hill-RBF). Accuracy of intraoperative aberrometer was compared with other formulas in terms of mean absolute prediction error (MAE), percentage of patients within 0.5 D and 1 D of their target, and percentage of patients going into hyperopic shift. Results: Sixty-five eyes (57 patients) were included. In terms of MAE, both Hoffer Q (MAE = 0.30) and IA (MAE = 0.32) were significantly better than Haigis, SRK/T, and Barrett Universal II (P < 0.05). Outcomes within ±0.5 D of the target were maximum with Hoffer Q (80%), superior to IA (Hoffer Q > IA > Holladay 2 > Hill-RBF > Haigis > SRK/T > Barrett Universal II). Hoffer Q resulted in minimum hyperopic shift (30.76%) followed by Hill-RBF (38.46%), Holladay 2 (38.46%), Haigis (43.07%), and then IA (46.15%), SRK/T (50.76%) and Barrett Universal II (53.84%). Conclusion: IA was more effective (statistically significant) in predicting IOL power than Haigis, SRK/T, and Barrett Universal II although it was equivalent to Hoffer Q. Hoffer Q was superior to all formulas in terms of percentage of patients within 0.5 D of their target refractions and percentage of patients going into hyperopic shift.

To perform a comparative clinical analysis of the safety, efficacy, and predictability of two surgical procedures (ie, small incision lenticule extraction [SMILE] and femtosecond laser-assisted LASIK [FS-LASIK]) to correct myopia. Sixty eyes of 31 patients with a mean spherical equivalent of -5.13 ± 1.75 diopters underwent myopia correction with the SMILE procedure. Fifty-one eyes of 27 patients with a mean spherical equivalent of -5.58 ± 2.41 diopters were treated with the FS-LASIK procedure. Postoperative uncorrected and corrected distance visual acuity, manifest refraction, and higher-order aberrations were analyzed statistically at 1 and 3 months postoperatively. No statistically significant differences were found at 1 and 3 months in parameters that included the percentage of eyes with an uncorrected distance visual acuity of 20/20 or better (P = .556, .920) and mean spherical equivalent refraction (P = .055, .335). At 1 month, 4 SMILE-treated eyes and 1 FS-LASIK-treated eye lost one or more line of visual acuity (P = .214, chi-square test). At 3 months, 2 SMILE-treated eyes lost one or more line of visual acuity, whereas all FS-LASIK-treated eyes had an unchanged or corrected distance visual acuity. Higher-order aberrations and spherical aberration were significantly lower in the SMILE group than the FS-LASIK group at 1 (P = .007, .000) and 3 (P = .006, .000) months of follow-up. SMILE and FS-LASIK are safe, effective, and predictable surgical procedures to treat myopia. SMILE has a lower induction rate of higher-order aberrations and spherical aberration than the FS-LASIK procedure.

PurposeTo evaluate the intrasession repeatability of anterior corneal topographic and aberrometric measurements provided by a color-LED topographer as well as their interchangeability with those provided by a Scheimpflug-based system in healthy eyes.MethodsThirty-five healthy eyes of 35 patients (age, 16–66 years) were enrolled. A complete eye examination was performed in all cases including a complete corneal analysis with the Scheimpflug-based system Pentacam (Oculus Optikgeräte) (one measurement) and the Cassini system (i-Optics) (three consecutive measurements). Intrasession repeatability of the Cassini measurements was assessed with the within-subject standard deviation (Sw) and the intraclass correlation coefficient (ICC). The Bland-Altman analysis was used to evaluate the agreement between both devices.ResultsMean Sw for keratometric readings was 0.02 mm (ICC ≥ 0.992), ranging between 0.16 and 0.05 D (ICC 0.930–0.978) for anterior and total astigmatic measurements. Mean Sw for asphericity and corneal diameter were 0.06 (ICC 0.926) and 0.03 mm (IC 0.997), respectively. Aberrometric parameters showed ICCs ≥ 0.816, except for Z42 (ICC 0.741) and Z44 (ICC 0.544). When comparing devices, statistically significant differences were found for most of topographic and aberrometric data (p ≤ 0.044). Likewise, ranges of agreement between devices were clinically relevant (keratometry > 0.06 mm; total astigmatic components > 0.69 D; asphericity 0.35; second-, third-, and fourth-order Zernike terms, more than 0.20, 0.13, and 0.01 μm, respectively).ConclusionsConsistent anterior corneal topographic, total corneal astigmatic, and aberrometric measurements are obtained with color-LED topography in healthy eyes, which are not interchangeable with those provided by the Scheimpflug-based topography.

Ocular aberrometry with a wide dynamic range for assessing vision performance and anterior segment imaging that provides anatomical details of the eye are both essential for vision research and clinical applications. Defocus error is a major limitation of digital wavefront aberrometry (DWA), as the blurring of the detected point spread function (PSF) significantly reduces the signal-to-noise ratio (SNR) beyond the ±3 D range. With the aid of Badal-like precompensation of defocus, the dynamic defocus range of the captured aberrated PSFs can be effectively extended. We demonstrate a dual-modality MHz VCSEL-based swept-source OCT (SS-OCT) system with easy switching between DWA and OCT imaging modes. The system is capable of measuring aberrations with defocus dynamic range of 20 D as well as providing fast anatomical imaging of the anterior segment at an A-scan rate of 1.6 MHz.