Implantation Of Aspheric Intraocular Lens Research Articles

A simultaneous post-LASIK sequential bilateral implantation of multifocal IOLs aimed at refraction correction. A clinical case

The article presents a clinical example of intraocular presbyopia correction in a patient who previously underwent laser vision correction by LASIK for mild myopia. Before the surgery, the distance VA mono- and binocular was 1.0, ADD for reading distance 40 cm +2.0 D, objective refraction sph +0.5 D cyl -0.25 D ax 980, left eye sph +0.75 D cyl -0.25 D ax 660. The patient was given a simultaneous bilateral refractive lens exchange with an implantation of a trifocal aspheric intraocular lens in the right eye and a trifocal toric aspheric intraocular lens in the left eye. We used the following IOL calculation formulas: ASCRS mean IOL power, Shammas formula, Barrett true K formula, Masket formula, Modified Masket formula, Haigis-L formula. 1 week postop: UDVA OU = 1.0, UNVA 40 cm = 1.0, UVA 70 cm = 0.7. The objective refraction OD was sph +0.0, D cyl -0.75 D ax 163, OS sph +0.25 D, cyl -0.0 D. The compliance with the modified algorithms of pre-and intraoperative behavior of the operating team, thorough preparation of the patient, careful calculation of the IOL allowed us to obtain the predictive refractive result with a high level of visual satisfaction and absence of undesirable postoperative phenomena. The patient underwent the examination with Salzburg reading desk before and after the surgery, to confirm the excellent functional results of the treatment. Despite the fact that simultaneous same day IOL implantation in both eyes, especially in eyes with previously operated corneas, is still disputable, the above case confirms that with modern equipment, precise multi formula calculation, and ample experience help achieve excellent functional and refractive results.

Functional Approach to IOL Selection in Eyes With Combined Cataract and Keratoconus With an Option for Refractive Lens Exchange.

To evaluate spherical intraocular lens (IOL) implantation for cataracts in keratoconic eyes followed by optional refractive toric lens exchange to improve uncorrected visual acuity. This retrospective study evaluated cataract surgery outcomes in keratoconic eyes. Eyes treated with a spherical IOL targeted for -2.00 diopters (D) either achieved acceptable manifest refraction and desired exchange with a toric IOL (Group 1); achieved satisfactory manifest refraction and chose to use spectacles or contact lenses (Group 2); or did not achieve acceptable refraction and used contact lenses (Group 3). Group 4 had single-stage toric IOL implantation with plano target. Corrected and uncorrected distance visual acuity (CDVA and UDVA) and keratometry were analyzed. Groups 1 to 4 had 18, 23, 18, and 26 eyes, respectively. A staged toric exchange resulted in significantly better (P = .02) UDVA (mean: 0.15 logMAR; 20/25 Snellen) than initial toric IOL implantation (0.24 logMAR; 20/30 Snellen). All toric IOL exchange eyes achieved 20/30 or better CDVA and 94% had 20/40 or better UDVA. Mean manifest cylinder significantly decreased from 3.39 D before lens exchange to 1.10 D postoperatively. Initial implantation of a spherical IOL in keratoconic eyes allows basing toric calculations on the manifest refraction, which may be more reliable than keratometry measurements in keratoconic eyes. UDVA after staged toric IOL exchange was significantly better than after initial toric IOL implantation. Importantly, by staging use of toric lenses, the authors avoided cases where patients required a rigid contact lens after a toric IOL was implanted. [J Refract Surg. 2024;40(4):e207-e217.].

Aspheric hydrophobic acrylic intraocular lens outcomes in patients with additional ocular pathology

Objectives: The objective of the study was to examine the real-world visual performance, refractive outcomes, and glistening occurrence of a hydrophobic acrylic aspheric monofocal intraocular lens (IOL) in patients with ocular comorbidities. Materials and Methods: All cases of cataract surgery with the implantation of a hydrophobic acrylic aspheric monofocal IOL in a single centre between September 2020 and March 2022 were reviewed in a retrospective cohort study. Refraction (autorefract), visual acuity, peri- and post-operative complications, and the presence of posterior capsular opacification (PCO) and glistenings were recorded. Due to facility and surgeon preference, this lens was utilised predominantly for younger patients with additional ocular pathology. Results: Data regarding 15 patients (21 eyes) were collected. The mean age was 57.3 years (Range: 37–70). Eleven patients (73%) had ocular pathology in addition to cataracts. One patient was excluded due to a lack of follow-up. Post-operative refraction was available for 13 eyes (61%). The median follow-up time was five months. Corrected distance visual acuity (logarithm of the minimum angle of resolution) improved from 0.52 ± 0.54 to 0.17 ± 0.21 (mean ± standard deviation; P = 0.01); 95% confidence interval 0.08–0.26). 77% of eyes were within 0.5 D of the refractive target, and 92% were within 0.7 D. Six patients (30%) had documented PCO, with two requiring YAG capsulotomy. No patients had IOL glistenings. Conclusion: The hydrophobic aspheric monofocal IOL performs well for young patients with ocular pathology in addition to cataracts. Further, long-term follow-up will help to support its use for patients who require greater than standard longevity from an IOL.

Effectiveness and tolerability of the fixed combination of preservative-free drugs timolol and travoprost in glaucoma patients after cataract surgery

PURPOSE. The aim of the study was to evaluate the tolerability and effectiveness of the preservative-free combination eye drops timolol 0,5%/travoprost (Travapress Duo, ROMPHARM Company) when changing therapy in patients with initial and moderate stages of glaucoma after phacoemulsification of age-related cataract.METHODS. The study included 38 patients with disorders of the ocular surface with specific complaints, initial and moderate stages of glaucoma compensated for therapy with β-blockers and prostaglandin F2-α analogues. The patients were using monodrugs of these groups, or their fixed combinations. All patients had previously undergone phacoemulsification of age-related cataract with implantation of a monofocal aspherical intraocular lens. The main group consisted of 18 patients who underwent a change in antiglaucoma therapy to a preservative-free combination eye drops timolol 0,5%/travoprost (Travapress Duo, ROMPHARM Company) with once-per-day instillation regimen. Participants included in the control group (20 patients) remained on the treatment they had been using. All patients completed a questionnaire survey of subjective complaints and their condition, underwent assessment of the level of intraocular pressure (IOP), visual functions, parameters of the state of ocular surface (Schirmer test, epitheliopathy according to the Oxford scale), perimetric data on Humphrey 860 (Humphrey Field Analyzer III 860, Zeiss, USA), as well as morphometric parameters and indicators of retinal blood flow and optic nerve on OCT Cirrus 5000 Angioplex (Zeiss, USA) over three months of observation.RESULTS. After switching the drug all patients of the main group experienced a significant improvement in their subjective condition and gave less complaints about the ocular surface. At the same time, stable IOP compensation and no changes in retinal light sensitivity were achieved according to the results of perimetry, the morphometric data and indicators of retinal and optic nerve blood flow.CONCLUSION. The combined preservative-free eye drops timolol 0,5%/travoprost (Travapress Duo, ROMPHARM Company) is well tolerated by patients and is an effective antiglaucoma drug that allows achieving target IOP level with stabilization of morphological and functional parameters in patients with initial and moderate stages of glaucoma after previous cataract phacoemulsification.

Hypocalcemic cataract secondary to idiopathic hypoparathyroidism in an adolescent.

Idiopathic hypoparathyroidism is a rare endocrine disorder characterized by hypocalcemia secondary to inadequate parathyroid hormone secretion. Hypocalcemia-related cataract is most often observed in patients with postoperative hypoparathyroidism, whereas primary hypoparathyroidism-related cataract is rare and displays slow progression. Cataract usually occurs in people aged 18 to 50 years. Here, we describe a 17-year-old boy with bilateral cataract and a history of hypocalcemic tetany who was diagnosed with idiopathic hypoparathyroidism. Phacoemulsification with implantation of a monofocal aspherical intraocular lens was performed in the right eye; 6 months later, it was performed in the left eye. Elevated phosphorus and diminished calcium were observed in blood and aqueous humor. A deep anterior chamber, relatively thin central corneal thickness, large white-to-white distance, and thin lens were also observed. During follow-up, neither eye displayed intraocular lens decentration; best-corrected visual acuity was 20/20 in both eyes. These findings suggest that ophthalmologists should be vigilant when hypocalcemic tetany and cataract are present, especially in adolescents and young adults.

Visual function assessment of Chinese cataract patients after individual aspheric intraocular lens implantation according to preoperative cornea spherical aberration.

Aspheric intraocular lens (IOLs) implantation has been widely applied in cataract surgery. However, there is no consensus on the optimal guidance for the operations in IOLs implantation. This study evaluated the visual function of Chinese cataract patients six months after cataract surgery with two different guiding ideologies. We evaluated 50 patients (61 eyes) with implantation of different aspheric IOLs (SN60WF IOLs, ZCB00 IOLs, PY-60AD IOLs, AO IOLs) 6 months after cataract surgery. Twenty-four patients (30 eyes) under individual implantation were ascribed to group 1 and 26 patients (31 eyes) with randomized implantation were ascribed to the control group (group 2). Postoperatively parameters included monocular best-corrected visual acuity (BCVA), contrast sensitivity (CS), total spherical aberration Z (4, 0) at 5 mm pupil size, and patient satisfaction. The quality of life after operation was assessed through the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25). Six months after cataract operation, the contrast sensitivity with glare of group 1 at 2.5∘ was 0.697 ± 0.027, and 0.532 ± 0.049 in group 2. Besides, there was no significant difference at any other special frequency. The mean spherical aberration Z (4, 0) at 5 mm pupil size in group 1 was 0.015 ± 0.028 um, and in group 2 was 0.043 ± 0.109 um, with a significant difference (p< 0.01). The mean scores obtained from NEI VFQ-25 were not significantly different. It is effective to implant aspheric IOLs individually according to preoperative corneal spherical aberration. Patients obtained better contrast sensitivity with glare at 2.5∘, but there was no significant difference in BCVA, contrast sensitivity at other special frequency, and subjective visual function.

Comparison of two one-piece acrylic foldable intraocular lenses: Short-term change in axial movement after cataract surgery and its effect on refraction.

To compare the change in intraocular lens (IOL) axial movement, corneal power, and postoperative refraction of eyes implanted with two different single-piece, open loop, acrylic foldable IOLs with planar-haptic design: one IOL with hinges vs. one IOL without hinges. The role of IOL axial movement on short-term refractive shift after cataract surgery was also evaluated. This retrospective comparative study enrolled consecutive patients who had phacoemulsification with aspheric IOL implantation. The IOL depth (the distance from corneal endothelium to IOL surface) and corneal power were measured via anterior-segment optical coherence tomography at 4 days and 1 month postoperatively. The changes in axial movement of the IOL, corneal power, and manifest refractive spherical equivalent (MRSE) were compared among groups, and the correlations between each lens were evaluated. IOL with hinges was implanted in 42 eyes of 42 patients and IOL without hinges was implanted in 42 eyes of 42 patients. The change in axial movement between 4 days and 1 month was significantly smaller in the IOL with hinges group than in the IOL without hinges group (p < 0.001). The axial movement of IOL with hinges did not correlate with the MRSE change; however, the forward shift of IOL without hinges correlated with the myopic refractive change (Pearson r = 0.62, p < 0.001). The postoperative axial movement of IOL was more stable in the IOL with hinges group than the IOL without hinges group between 4 days and 1 month after cataract surgery. Even though the two study IOLs with planar-haptic design are made of similar acrylic materials, other characteristics such as hinge structure may affect IOL stability in the bag.

Refractive and Visual Outcomes of a Monofocal Non-Constant Aberration Aspheric Intraocular Lens.

PurposeTo evaluate the refractive and visual outcomes following cataract surgery and implantation of a new monofocal non-constant aberration aspheric intraocular lens (IOL).MethodsNinety eyes of 86 patients who underwent implantation the CT LUCIA 621P IOL (Carl Zeiss Meditec AG) were retrospectively analyzed in this study. Main outcome measures were refractive error and monocular corrected distance visual acuity (CDVA) and monocular uncorrected distance visual acuity (UDVA) values. Patients were evaluated at 1-month post-surgery and intra- and post-operative complications were recorded.ResultsEighty percent of the eyes showed a CDVA of 20/25 or better before surgery. The postoperative mean values of monocular distance Snellen decimal UDVA and CDVA were 0.64±0.22 and 0.89±0.13, respectively. All eyes showed the same or better difference between UDVA and CDVA. In relation to the postoperative spherical equivalent, the highest percentage of eyes, 31.11%, was for the range between −0.50 and −0.14D followed by 22.22% for the ±0.13D range. Ninety percent of the eyes were within ±1.00 D and 73.33% of eyes within ±0.50 D. The mean postoperative spherical equivalent was −0.18±0.55D. 37.78% and 76.67% of the eyes showed a value ≤0.50 D and ≤1.00D, respectively, being the mean postoperative refractive cylinder −0.81±0.50D. No adverse events were reported in whole sample intra and postoperatively.ConclusionThe present study shows that cataract surgery with an monofocal non-constant aberration aspheric IOL implantation resulted in good visual performance and refractive outcomes. This lens may be considered as a valid choice for patients in a standard-routine cataract surgery practice.

Comparison of Visual Outcomes Between Toric Intraocular Lenses and Clear Corneal Incisions to Correct Astigmatism in Image-Guided Cataract Surgery.

PurposeTo compare the astigmatism correction effects of toric intraocular lenses (IOL) and clear corneal incisions during image-guided cataract surgery.MethodsAll patients with regular corneal astigmatism of 0.75–1.5 D underwent cataract surgery and astigmatism correction using the Callisto eye image-guided system. One group had implantation of an AcrySof toric IOL. Another group had implantation of aspheric IOL with 3.0 mm single clear corneal incision (SCCI) on the steep axis. Uncorrected and best-corrected spectacle visual acuity, refraction, and toric IOL axis were evaluated at 1, 4, and 12 weeks postoperatively.ResultsSixty-eight eyes of 68 patients were included. The mean residual refractive cylinder was 0.34 ± 0.40 D in the toric group and 0.64 ± 0.57 D in the SCCI group. There were no significant differences in residual refractive cylinder, spherical equivalent, uncorrected distance visual acuity (UDVA), and best-corrected spectacle visual acuity (BCSVA) between groups. The percentage of the residual cylinder within ± 0.50 D was 75 and 56% for toric and SCCI cases, respectively (p > 0.1). The mean surgical induced astigmatism vector was 0.61 ± 0.29 D in the SCCI group and 1.04 ± 0.38 D in the toric group. The mean magnitude of error was negative (−0.54 ± 0.48 D) and the correction index was <1.0 (p < 0.05) in SCCI group. At 3 months, all toric IOL alignment errors were within 5 degrees from the intended axis.ConclusionsBoth toric IOL and SCCI can correct low and medium astigmatism effectively with the help of a precise image-guided system.

Efficacy comparison between toric intraocular lens and aspheric intraocular lens plus steep-axis incision in cataract patients with low corneal astigmatism.

The present study aimed to evaluate and compare the efficacy of toric intraocular lens (IOL) implantation and aspheric IOL implantation with steep-axis incision for correcting mild to moderate corneal astigmatism in cataract patients. A prospective, single-center, open label, randomized, two-arm study was designed. Cataract patients with corneal astigmatism of 1.0-2.0D were enrolled and divided into test and control groups. The test group had the AcrySof® IQ Toric IOL implanted and the control group had the AcrySof® IQ IOL implanted with a steep-axis corneal incision. All patients underwent examinations of uncorrected distance visual acuity (UCDVA), corrected distance visual acuity (CDVA), subjective refraction, and corneal astigmatism before surgery and at the 1-day, 1-month, and 3-month follow-ups. Vector astigmatism analysis was evaluated using the Alpins method. We enrolled 26 eyes of 20 patients in the study, with 13 eyes in each group. The test group had better vision than the control group at the 3-month follow-up and had more cases with a UCDVA of 20/20 (10/13 vs. 4/13). The surgically induced astigmatism (SIA) vector of the test group was higher than that of the control group (1.22±0.64 vs. 0.84±0.45). The correction index of the test group was closer to 1 compared to that of the control group (0.7 vs. 0.46). Approximately 85% of patients in the test group had an angle of error within -15° to 15°. However, only 23% of patients in the control group were within that range. Though steep-axis corneal incision was cost-saving and easy-to perform, its astigmatismcorrecting efficacy was not as good as the Toric IOL implantation for cataract patients with low to moderate corneal astigmatism.

Safety and efficacy of A1-UV aspheric intraocular lens implantation over the postoperative 5 years

Objective: To evaluate the clinical safety and efficacy of A1-UV aspheric intraocular lens (IOL) implantation over the postoperative 5 years. Methods: Prospective cohort study. The subjects came from a finished multicenter, randomized and controlled clinical trial with a follow-up period of 1 year from April to November 2012. The clinical research centers were Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Peking University Third Hospital, Tianjin Medical University Eye Hospital, and Daping Hospital of Army Medical University. Cataract patients in the experimental group were implanted with A1-UV type IOL, while cataract patients in the control group were implanted with SN60WF type IOL, and monocular patients were enrolled. From April to May 2018, patients enrolled in the previous study were recalled for follow-up and continued observation. The visual acuity, spherical equivalent, postoperative complications, non-contact intraocular pressure and subjective evaluation results were statistically analyzed preoperatively, at 1 to 2 days, 1 week, 1 month, 3 months, 6 months, 1 year and 5 years after operation. The main statistical methods included Mann Whitney U test, Wilcoxon signed rank test, independent sample t test, chi square test and Fisher exact test. Results: A total of 42 subjects (22 in the experimental group and 20 in the control group) completed 5-year continuous observation. Among the 42 subjects, 28 were female and 14 were male. The age was (70±9) years, and the time from surgery to recall was (5.77±0.19) years. The age, gender distribution, left/right eye distribution, axial length, IOL power and nucleus hardness classification data of the experimental group and the control group were balanced and comparable (all P>0.05). At different visiting time points, there was no significant difference in the best corrected distance visual acuity (BCDVA), best corrected near visual acuity (BCNVA), uncorrected distance visual acuity (UCDVA) and uncorrected near visual acuity (UCNVA) between the groups (all P>0.05). At 5 years after operation, the UCDVA, BCDVA and BCNVA of the two groups were significantly improved compared with the baseline [all P<0.01; UCDVA was improved from 0.75 (0.30 to 1.30) to 0.10 (-0.10 to 0.70) in the experimental group and from 0.75 (0.30 to 1.60) to 0.20 (-0.10 to 0.80) in the control group; BCDVA was from 0.60 (0.10 to 1.00) to 0.00 (-0.10 to 0.54) in the experimental group and from 0.60 (0.10 to 1.60) to 0.10 (-0.10 to 0.50) in the control group; BCNVA was from 0.55 (0.00 to 1.10) to 0.10 (-0.10 to 0.60) in the experimental group and from 0.55 (0.10 to 1.60) to 0.10 (-0.20 to 0.60) in the control group], but there was no significant change in the UCNVA (both P>0.05). There were no significant differences in the spherical equivalent, intraocular pressure, subjective evaluation of visual adverse symptoms, distance vision spectacle independence and comprehensive evaluation of satisfaction between the groups (all P>0.05). In the experimental group, one eye (4.5%) had an abnormal pupil, one eye (4.5%) had an abnormal IOL with a few particles on the surface of the IOL but no glistening, and 3 eyes (13.6%) had posterior capsular opacification (PCO); in the control group, one eye (5.0%) had an abnormal cornea, five eyes (25.0%) had abnormal IOLs [one eye (5.0%) had IOL calcification, and four eyes (20.0%) had IOL glistening], and one eye (5.0%) had PCO with posterior capsular folds and IOL tilt. There was no significant difference in PCO and IOL abnormality between the two groups (both P>0.05), but there was significant difference in the occurrence of IOL glistening (P=0.04). Conclusion: The long-term effect of A1-UV aspheric IOL on improving the UCDVA is stable and good, with high subjective satisfaction of patients, a low incidence of PCO, no glistening and good biocompatibility, over the postoperative 5 years. (Chin J Ophthalmol, 2021, 57: 41-47).

Comparison of visual quality after implantation of A1-UV and SN60WF aspheric intraocular lens.

To compare the visual performance of pseudophakic eyes implanted with A1-UV and SN60WF aspheric intraocular lens (IOL), and to investigate the correlations between visual quality parameters and pupil size. This prospective comparative study included 105 eyes of 90 patients with age-related cataract who underwent uneventful phacoemulsification. The subjects were divided into two groups according to the implanted IOL type. Three months postoperatively, visual acuity and contrast sensitivity were measured, wave-front aberrations were assessed using a KR-1W aberrometer (Topcon), and objective optical quality parameters were performed using an optical quality analysis system-OQAS II (Visiometrics). Independent sample t-test and Spearman correlation analysis were used for data analysis. There were no significant differences found in visual acuity, contrast sensitivity and visual quality parameters between the two groups (P>0.05). The measured intraocular spherical aberration (SA) in A1-UV IOL eyes of -0.19±0.05 µm was close to the designed SA value of -0.20 µm. The modulation transfer function cutoff, Strehl ratio and OQAS values were negatively correlated with pupil size in both groups (P<0.01). The subjective and objective visual quality in pseudophakic eyes with A1-UV and SN60WF IOLs are comparable. For aspheric IOL eyes, visual quality decreases with increasing pupil size.

Extended Depth of Focus Versus Monofocal IOLs: Objective and Subjective Visual Outcomes.

To evaluate and compare the objective and subjective outcomes between bilateral implantation of the extended depth of focus (EDOF) Mini Well intraocular lens (IOL) and the aspheric monofocal Mini-4-Ready IOL (both SIFI S.p.A., Catania, Italy). This prospective comparative study included 25 patients (50 eyes) bilaterally implanted with an EDOF Mini Well IOL (EDOF group) and 25 patients (50 eyes) bilaterally implanted with a Mini-4-Ready IOL (monofocal group). Three-month follow-up data included corrected and uncorrected distance visual acuity at 4 m and 80, 67, and 40 cm. Defocus curves, subjective and objective contrast sensitivity, and objective optical quality (modulation transfer function cutoff and Strehl ratio calculated with Optical Quality Analysis System [OQAS]; Visiometrics SL, Terrassa, Spain), halometry, and reading performance were measured. Subjective visual quality was evaluated based on National Eye Institute Refractive Error Quality of Life Instrument 42 (NEI RQL-42) scores. Postoperative uncorrected and corrected monocular and binocular intermediate and near visual acuity was significantly better in the EDOF group (P < .001). No differences were observed for distance visual acuity (P ⩾ .312). Defocus curve outcomes for myopic values were better in the EDOF group (P < .001). No significant differences were found in hyperopic (obtained in steps of +0.50 diopters [D] from emmetropia to 1.50 D) values (P ⩾ .095), contrast sensitivity curves (P ⩾ .087), or OQAS outcomes (P ⩾ .138). Halometric values were significantly better in the monofocal group (P < .05). There was a correlation between mean keratometry values and intermediate/near visual acuity. Significantly better NEI RQL-42 subscale scores for near vision, far vision, activity limitations, glare, dependence on correction, and suboptimal correction were noted in the EDOF group (P < .05). Intermediate and near visual acuity was better after EDOF IOL than after aspheric monofocal IOL implantation while maintaining similar levels of visual quality, except for halo perception. [J Refract Surg. 2020;36(4):214-222.].

Comparison of Toric Intraocular Lens Alignment Using Image-Guided System and Manual Marking Technique.

Objectives:The aim of this study was to compare the accuracy of an image-guided system (Callisto eye; Carl Zeiss, Oberkochen, Germany) with the manual marking technique in the positioning of a toric intraocular lens (IOL).Methods:A total of 80 eyes of 80 patients who underwent cataract surgery with a monofocal, single-piece, hydrophobic, biconvex, toric, aspheric IOL (Acrysof IQ SN6AT, Alcon Laboratories, Inc., Fort Worth, TX, USA) implantation were included. Before surgery, all of the patients underwent a complete eye examination that included evaluation of uncorrected (UCVA) and corrected distance visual acuity (CDVA), spherical equivalent (SE), astigmatic refraction (AR), keratometry, biometry, as well as meridian registration with the IOLMaster 700 (Carl Zeiss, Oberkochen, Germany), slit lamp examination, intraocular pressure measurement, and dilated retinal examination. The diopter of the toric IOL was calculated with an online calculator (Alcon, Fort Worth, TX, USA). At 3 months post surgery, the UCVA, CDVA, SE, and residual astigmatism were recorded, and the pupils of all of the patients were fully dilated to determine the toric IOL marker positions.Results:Group 1, the Callisto eye system group, comprised 45 eyes, and Group 2, the manual marking technique group, was composed of 35 eyes. The preoperative values of both groups were statistically similar in terms of the SE, corneal cylinder, axial length, logMAR UDVA, and logMAR CDVA. At postoperative 3 months, there were no significant differences between the 2 groups in the logMAR UDVA, logMAR CDVA, degree of misalignment of toric IOL, or mean deviation from target-induced astigmatism values. The mean deviation degree from the intended axis was 2.04±1.84 in the Callisto eye system group (Group 1) and 3.24±2.64 in the manual marking technique group (Group 2). However, this difference did not have any effect on the logMAR UDVA.Conclusion:The image-guided markerless system was found to be as effective as manual marking in the positioning of toric IOLs.

Personalized aspheric intraocular lens implantation based on corneal spherical aberration: a review.

With the evolution of cataract surgery from visual rehabilitation to refractive surgery, aspheric intraocular lenses (IOLs) are being increasingly used in the field of ophthalmology. This increased use can be attributed to negative or zero spherical aberrations with unique optical designs, which counteract some of the positive spherical aberrations of the cornea. These alterations reduce the total spherical aberration of human eyes and improve the visual acuity in patients with cataract postoperatively. At present, various types of aspheric IOLs are used worldwide. Although the implantation of aspheric IOL is beneficial to the patients who need correction of spherical aberrations, much controversy is still associated with ocular residual spherical aberrations that facilitate the best visual quality for patients postoperatively. In order to provide reference for future clinical work and scientific research, this report reviews the relationship between the ocular residual spherical aberration of human eyes and visual quality.

Comparison of three different diffractıve multifocal intraocular lenses with a +2.5, +3.0, and +3.75 diopter additıon power

PurposeTo compare the functional outcomes and astigmatic tolerability after implantation of multifocal intraocular lenses (IOLs) with a +2.5, +3.0, and +3.75 diopter (D) addition power. MethodsThis study included 122 eyes of 61 patients who had bilateral cataract extraction and implantation of diffractive aspheric multifocal acrylic IOLs with +2.5 D (+2.5 group), +3.0 D (+3.0 group), and +3.75 D (+3.75 group) addition powers. 1-year after surgery, distance corrected near (DNVA) and intermediate (DIVA) visual acuities at 32, 40, 45, 50, 55, and 60 cm; and contrast sensitivity measurements under photopic, mesopic and mesopic with glare conditions; spherical and astigmatic defocus testing; distance-intermediate-near vision patient satisfaction levels; spectacle dependance; patient-reported outcomes were assessed binocularly. ResultsThe +2.50 D group had better DIVA than both +3.0 group and +3.75 groups at 45 cm, 50 cm, 55 cm, and 60 cm (p < 0.05). The +3.75 group had better DNVA than both +2.5 and +3.0 IOL groups at 32 cm (p < 0.05). There was no significant difference in mean contrast values at all frequencies between three IOL groups (p > 0.05). The +2.50 D group showed better astigmatic tolerability than +3.00 group (at 2.00 D) and +3.75 group (at 1.50 D, and at 2.00 D) (p < 0.05). ConclusionMultifocal IOLs with +2.5 add power have better intermediate vision, but worse near vision compared to multifocal IOLs with +3.00 D and +3.75 D add power. Multifocal IOLs with +2.50 D add power tend to have better astigmatic defocus tolerability than multifocal IOLs with +3.00 D and +3.75 D add powers.

Visual Function after Implantation of a Presbyopia-Correcting Trifocal Intraocular Lens

Purpose: To evaluate distance, intermediate, and near visual performance in patients implanted with a trifocal aspheric presbyopia-correcting intraocular lens (IOL). Methods: Forty patients were bilaterally implanted with the AcrySofIQ PanOptix IOL after femtosecond laser-assisted lens surgery. Binocular best corrected distance visual acuity (CDVA) (4 m), best distance-corrected near visual acuity (DCNVA) (40 and 30 cm), best corrected distance intermediate visual acuity (DCIVA) (70, 60, and 50 cm), binocular distance contrast sensitivity under photopic conditions (85 cd/m²), and defocus curves were evaluated at 6-months. Results: Six months postoperatively, the mean binocular Snellen decimal CDVA and DCNVA were 0.94 ± 0.10 (ranging from 0.70 to 1.25) and 0.85 ± 0.13 (ranging from 0.63 to 1.00), respectively. At a distance, all patients showed a cumulative binocular distance-corrected visual acuity of 0.8 or better, and about 80% (n = 31) of the patients had a value of 1.0 (20/20). At near and intermediate distances, all patients showed a cumulative distance-corrected visual acuity of 0.5 (20/40) or better at 30, 40, 50, 60, and 70 cm. Specifically, 50 cm showed the highest percentage of patients with larger values of visual acuity (60% [n = 26] with 20/20). Defocus curve showed a wide range of useful vision with two peaks of best visual acuity at distance and at 50 cm, and the binocular distance contrast sensitivity was within normal limits. Conclusions: The outcomes of the present study show that the visual performance obtained with bilateral implantation of the trifocal aspheric AcrySofIQ PanOptix IOL is good at far, intermediate, and near distances.

Objective optical quality in eyes with customized selection of aspheric intraocular lens implantation

BackgroundTo compare the postoperative optical quality in eyes with customized selection and random selection of aspheric intraocular lens (IOL) implantation.MethodsA prospective, nonrandomized study was implemented in adult cataract patients who underwent unilateral phacoemulsification with aspheric IOL implantation. Patients were allocated into two treatment groups: a customized group and a control group. In the customized group, the aspheric IOL selection was based on the corneal spherical aberration to enable the postoperative target ocular spherical aberration closest to zero; in the control group, the aspheric IOLs were chosen using a random strategy. Primary outcome measurements included the following objective optical quality assessments: higher-order aberrations obtained by a Hartmann-shack aberrometer at 4 mm and 6 mm pupil diameters; objective scatter index (OSI), modulation transfer function (MTF) cut-off, Strehl ratio (SR) and a simulated contrast visual acuity—optical quality analysis system value (OV) obtained by a double-pass system with a 4-mm aperture. Subjective visual acuity was measured as secondary outcome. All the patients were followed up for 3 months.ResultsEighty-four patients in the customized group and 78 patients in the control group were evaluated. There was no significant difference in postoperative visual acuity between the two groups (P > 0.05). Significantly less ocular higher-order aberrations were shown in the customized group (P < 0.05). No significant difference was shown in OSI, MTF cut-off, SR and OV between the two groups (P > 0.05).ConclusionsAlthough customized selection of aspheric IOL implantation showed less postoperative ocular aberrations, it performed similarly to random selection of aspheric IOL implantation in terms of postoperative visual acuity, simulated contrast visual acuity, intraocular scatter, modulation transfer function and Strehl ratio.Trial registrationRetrospectively registered on 07/06/2019. Registration number: ChiCTR1900024356.

Pilot evaluation of refractive prediction errors associated with a new method for ray-tracing–based intraocular lens power calculation

To investigate the accuracy of a new ray-tracing-based intraocular lens (IOL) power calculation method and to compare the outcomes with different IOL calculation formulas. Hanusch Hospital, Vienna, Austria. Theoretical prospective monocentric study. Monofocal aspheric plate haptic IOL (CT Asphina 409M/MP) implantation was performed in 40 cataractous eyes. At 1month postoperatively, manifest refraction and optical coherence tomography-based biometry (IOLMaster 700) was conducted. The refractive spherical equivalent absolute error of the ray-tracing IOL power calculation method, based on individualized eye model data, a physical lens position predictor, retinal image quality metrics criteria for IOL power selection, and exact IOL design information was calculated and compared with the outcomes using the Barrett Universal II, Hill-RBF, SRK/T, and Haigis formulas. There was no significant difference in absolute errorbetween ray tracing and the Barrett Universal II (0.37 diopter [D]±0.29 [SD]; P=.601) or Hill-RBF (0.39±0.31 D; P=.170). However, the absolute error was significantly lower compared with the Haigis formula (0.42±0.36 D; P=.029) and SRK/T (0.52±0.39 D; P=.020). The refractive prediction of absolute error within ±0.25 D and within ±0.50 D ranged between 48% (ray tracing) and 25% (SRK/T), and between 80% (ray tracing) and 55% (SRK/T), respectively. The new ray-tracing-based IOL power calculation method was an accurate procedure and showed promising preliminary results not only for the refractive outcome, but also for surgeon and patient education as well as the management of patient expectations.

Two-stage procedure in the management of selected cases of keratoconus: clear lens extraction with aspherical IOL implantation followed by WFG-PRK.

To assess the objective and subjective results of a two-stage procedure for management of keratoconus: clear lensectomy with aspherical intraocular lens (IOL) implantation followed by wave front-guided photorefractive keratotomy (WFG-PRK). This prospective interventional non-randomized study included patients aged 35 years old or more with grade I and II stable keratoconus, a clear visual axis, minimal corneal thickness (MCT) 420 µm or more and average keratometric reading (K) less than 54 diopter (D). Refraction of all selected eyes should be -8.00 D sphere or more with less than -6.00 D cylinder and could be corrected two lines or more with spectacles or contact lenses. All studied eyes underwent a two-stage approach treatment: first refractive lens exchange and aspherical IOL implantation followed, after at least 3mo, by WFG-PRK. Pre and postoperative complete ophthalmological examination were performed. Topographical, visual and aberrometric results were recorded and evaluated during 6mo follow up period. Moreover, patient satisfaction and other subjective outcomes were also analyzed. The 13 eyes of 11 patients diagnosed with stable keratoconus and aged from 39 to 49y (42.4±6.2y) were enrolled in the study. At baseline, 8 eyes had grade I and 5 eyes had grade II keratoconus. The manifest sphere was -10.3±4.2 D (ranged from -8.0 to -14.0 D) and the manifest cylinder was -4.2±1.2 D (ranged from -1.75 to -5.50 D). After the two-stage procedure, sphere and cylinder reduced significantly to -0.43±0.22 D and -1.3±0.72 D respectively (P<0.001). There was also a highly significant improvement in the mean uncorrected distance visual acuity (UDVA) from logMAR 1.41±0.49 preoperatively to 0.51±0.16 postoperatively (P<0.001) and the mean corrected distance visual acuity (CDVA) from 0.76±0.24 preoperatively to 0.49±0.13 after the operation (P<0.001). All aberrometric and mesopic vision parameters and most of the topographical indices demonstrated highly significant improvement that remains stable until the end of follow up. All recorded subjective data revealed a high degree of patient satisfaction. Two-stage approach (clear lens exchange with monofocal IOL followed by WFG-PRK) in selected cases of keratoconus is a safe, effective and highly predictable procedure with satisfactory visual and refractive results.