Manifest Refraction Spherical Equivalent Research Articles

Evaluation of clinical outcomes following implantation of a sub-2-mm hydrophilic acrylic MICS intraocular lens.

To evaluate clinical outcomes following sub-2-mm microincision cataract surgery (MICS) and intraocular lens (IOL) implantation. Five EU clinical sites. Prospective, multicenter, open-label, single-arm, non-randomized. Preoperative assessment involved visual acuity (VA), intraocular pressure and biometry measurements. 1.4-mm wound-assisted or 1.8-mm MICS was performed. Follow-up visits were made 1day, 1-2weeks, 1-2 and 4-6months after surgery. The incision size, corrected distance VA (CDVA), uncorrected distance VA, manifest refraction spherical equivalent (MRSE), refraction predictability/stability and IOL decentration were assessed. At 12-, 18-, and 24-month, long-term centration, posterior capsular opacification (PCO) and Nd:YAG capsulotomy rates were investigated. A total of 103 eyes were implanted with the study IOL (INCISE, Bausch & Lomb), 96 of which were included in visual outcome analysis. A mean 6-month CDVA of - 0.02 logMAR (20/20 + 1) was observed and 75 eyes (79.8%) and 93 eyes (98.3%) achieved a visual acuity of at least 20/20 or 20/40. Mean MRSE was - 0.20 ± 0.60D. Mean absolute predictive error was 0.44 ± 0.36D, with 90.4% within 1.00D of target. Mean total decentration was 0.35 ± 0.36mm at 6months and 0.32 ± 0.14mm at 24months (p > 0.05). 24-month evaluation of posterior capsular opacification score was 0.03 for the central area. A Nd:YAG rate of 3.4% was observed at 24months. The new MICS IOL provided excellent visual outcomes and was safe and effective for the sub-2-mm procedure. The MICS IOL demonstrated long-term centration, stability and a low rate of PCO development.

Photorefractive intrastromal corneal crosslinking for treatment of myopic refractive error: Findings from 12-month prospective study using an epithelium-off protocol

To assess the long-term effectiveness and safety of photorefractive intrastromal corneal crosslinking (CXL) in patients with low myopia. Ruhr University Eye Hospital, Bochum, Germany. Prospective case series. Healthy eyes with myopia were treated with photorefractive intrastromal CXL using the Mosaic System. Riboflavin 0.1% solution (VibeX Rapid) was topically administered, followed by 365nm ultraviolet-A (30mW/cm2) irradiance. Efficacy was assessed by theuncorrected distance visual acuity (UDVA), manifest refraction spherical equivalent (MRSE), and keratometry. Safety was assessed by corrected distance visual acuity (CDVA), slitlamp biomicroscopy, endothelial cell count, and adverse event rates. Fourteen patients (24 eyes) with a mean age of 35.7years were included. At all follow-ups, a statistically significant improvement in UDVA was observed (all P<.001). The CDVA progressively improved from 1month postoperatively and a statistically significant improvement was achieved at 12months (P<.001). The average reduction in manifest sphere was 0.90 diopter (D)±0.40 (SD) by 12months. There were no significant differences in mean manifest sphere and MRSE at 3, 6, or 12months. Compared with baseline, significant reductions in corneal curvature were also observed at all follow-ups (all P<.05). There were no significant changes in endothelial cell density (P=1.00) or number of cells (P=.95) at 12months postoperatively, and no adverse events were reported. Photorefractive intrastromal CXL was a safe and efficacious treatment of refractive error in patients with low myopia.

Outcomes of presbyopia-correcting intraocular lenses after laser in situ keratomileusis.

Laser in situ keratomileusis (LASIK) is the most common refractive surgery in young patients, which aims at providing a clear distance vision without the use of spectacles. With time, these patients develop symptomatic cataract, which affects activities of daily living, and to improve visual acuity, intraocular lens (IOL) implantation can be considered. In post-myopic LASIK patients, to allow continuation of spectacle independence, the implantation of presbyopia-correcting IOLs is a suitable option. The purpose of this retrospective case series is to report the visual outcome and quality in post-myopic LASIK eyes after the implantation of AT LISA tri839MP IOL. Twenty eyes of 13 patients with history of myopic LASIK within 20years underwent phacoemulsification by one single surgeon. All eyes were implanted with AT LISA tri839PMP IOL, and their outcomes were evaluated at 6months postoperation. The mean postoperative uncorrected distance visual acuity (VA) is 0.28 ± 0.29, while the corrected distance VA is 0.06 ± 0.14. The mean postoperative uncorrected near VA is 0.02 ± 0.05, while the corrected near VA is 0.01 ± 0.02. The mean postoperative manifest refraction spherical equivalent (SE) is - 0.92 ± 0.76D. There is a statistically significant difference between the preoperative and postoperative refraction (p = 0.02), which shows a postoperative myopic shift. There is also a statistically significant difference between the mean targeted SE and postoperative manifest refraction SE (p = 0.00). Only one out of 20 eyes (5%) reported halo and glare symptoms. Ten out of 20 eyes (50%) are able to achieve spectacles independence. In conclusion, in post-myopic LASIK eyes, AT LISA tri839MP provides a good visual outcome at both near and distance, but is more predictable at near than at distance. There is a myopic shift in the postoperative SE. Visual quality is satisfactory and has not been exacerbated. Most patients can remain to be spectacles free at all distances.

Biomechanical Properties of the Cornea Using a Dynamic Scheimpflug Analyzer in Healthy Eyes.

PurposeTo investigate biomechanical properties of the cornea using a dynamic Scheimpflug analyzer according to age.Materials and MethodsIn this prospective, cross-sectional, observational study, participants underwent ophthalmic investigations including corneal biomechanical properties, keratometric values, intraocular pressure (IOP), and manifest refraction spherical equivalent (MRSE). We determined the relationship of biomechanical parameters and ocular/systemic variables (participant's age, MRSE, IOP, and mean keratometric values) by piecewise regression analysis, association of biomechanical parameters with variables by Spearman's correlation and stepwise multiple regression analyses, and reference intervals (RI) by the bootstrap method.ResultsThis study included 217 eyes of 118 participants (20–81 years of age). Piecewise regression analysis between Corvis-central corneal thickness (CCT) and participant's age revealed that the optimal cut-off value of age was 45 years. No clear breakpoints were detected between the corneal biomechanical parameters and MRSE, IOP, and mean keratometric values. Corneal velocity, deformation amplitude, radius, maximal concave power, Corvis-CCT, and Corvis-IOP exhibited correlations with IOP, regardless of age (all ages, 20–44 years, and over 44 years). With smaller deformation amplitude and corneal velocity as well as increased Corvis-IOP and Corvis-CCT, IOP became significantly increased. We provided the results of determination of confidence interval from RI data using bootstrap method in three separate age groups (all ages, 20–44 years, and over 44 years).ConclusionWe demonstrated multiple corneal biomechanical parameters according to age, and reported that the corneal biomechanical parameters are influenced by IOP.

Comparative analysis of outcomes after wavefront-guided and wavefront-optimized laser in-situ keratomileusis in high myopic eyes

Purpose The aim was to evaluate and compare the clinical outcomes after laser in-situ keratomileusis (LASIK) in high myopia using wavefront-guided (WFG) and wavefront-optimized (WFO) ablation profiles provided by two different excimer laser platforms. Patients and methods Prospective, consecutive, comparative, and masked clinical trial including 41 high myopic eyes treated with WFG LASIK using the Advanced CustomVue system (WFG group) and 40 eyes treated with a WFO profile using the Allegretto EX-500 platform (WFO group). Visual, refractive, contrast sensitivity (CVS-1000), and aberrometric outcomes were evaluated in both groups of eyes during a 6-month follow-up. Results The efficacy index was significantly better in the WFG group compared with the WFO (1.01±0.11 vs. 0.96±0.12, P=0.038). The safety index was also significantly better in the WFG group (1.03±0.12 vs. 0.94±0.11, P=0.011). All eyes achieved postoperatively an uncorrected distance visual acuity of 20/25 or better in the WFG group, whereas 87.5% of eyes achieved this uncorrected distance visual acuity in the WFO group. More eyes gained one line of corrected distance visual acuity in the WFG group (36.5 vs. 15.0%, P=0.015). Significantly lower postoperative manifest refraction spherical equivalent (P=0.045) and cylinder (P=0.005) were found in the WFG group. Manifest refraction spherical equivalent was within ±1.00 D in 90.3% and 80% of eyes in WFG and WFO groups, respectively (P=0.001). Contrast sensitivity decreased significantly only in the WFO group (P≤0.0397). More significant increase in high-order aberrations was found in the WFO group (P≤0.005). Conclusion WFG LASIK provides better efficacy, safety, predictability, and preservation of visual quality in high myopic eyes than WFO LASIK.

Visual rehabilitation in moderate keratoconus: combined corneal wavefront-guided transepithelial photorefractive keratectomy and high-fluence accelerated corneal collagen cross-linking after intracorneal ring segment implantation

BackgroundTo investigate the effects of combined corneal wavefront-guided transepithelial photorefractive keratectomy (tPRK) and accelerated corneal collagen cross-linking (CXL) after intracorneal ring segment (ICRS) implantation in patients with moderate keratoconus.MethodsMedical records of 23 eyes of 23 patients undergoing combined tPRK and CXL after ICRS implantation were retrospectively analyzed. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), corneal indices based on Scheimpflug tomography, higher-order aberrations (HOAs), and corneal biomechanical properties were evaluated before and after ICRS implantation, and at 1, 3, and 6 months after combined tPRK and CXL.ResultsThere were significant improvements in final logMAR UDVA and logMAR CDVA, and reductions in sphere, MRSE, and all corneal indices from baseline. Significant improvements in logMAR UDVA and reductions in sphere, MRSE, maximal keratometry, keratometry at the apex, mean keratometry, and keratoconus index were noted after ICRS implantation. After tPRK and CXL, significant improvements in logMAR UDVA and logMAR CDVA, and reductions in cylinder and all corneal indices were observed. There were significant improvements in final root mean square HOAs and coma aberrations from baseline, but no changes from baseline after ICRS implantation. Significant reductions in final radius and deformation amplitude from baseline were noted.ConclusionsCombined tPRK and accelerated CXL after ICRS implantation in moderate keratoconus appears to be a safe and effective treatment, providing an improvement in visual acuity, corneal indices, and HOAs.Trial registrationretrospectively registered (identification no. NCT03355430). Date registered: 28/11/2017.

Comparison of OKULIX ray-tracing software with SRK-T and Hoffer-Q formula in intraocular lens power calculation

PurposeTo compare the performance of OKULIX ray-tracing software with SRK-T and Hoffer Q formula in intraocular lens (IOL) power calculation in patients presenting with cataract. MethodsIn this prospective study, 104 eyes of 104 patients with cataract who underwent phacoemulsification and IOL implantation were recruited. Three IOL brands were used and for all eyes, IOL power calculation was performed using SRK-T, Hoffer Q formula and also OKULIX ray-tracing software. For all patients, axial length and keratometry data was obtained with IOLMaster 500 device and IOL power was determined using Hoffer Q and SRK-T formula. The IOL powers were also calculated using the OKULIX ray-tracing software combined with CASIA AS-OCT and IOLMaster 500 device. Optically measured axial length of eyes were inserted to OKULIX software from IOLMaster 500 device, and anterior and posterior tomographic and corneal pachymetry data was imported from CASIA AS-OCT into the OKULIX.The performance of each calculation methods was measured by subtracting the predicted postoperative refraction from the postoperative manifest refraction spherical equivalent (MRSE). For each of the 3 methods, the mean absolute prediction error was determined, too. ResultsThe mean value absolute prediction error by OKULIX, SRK-T and Hoffer Q formulas, respectively, were 0.42 (±0.03), 0.36 (±0.02) and 0.37 (±0.02). The mean absolute prediction error by OKULIX had no significant difference between three IOL groups (P = 0.96), and it was confirmed that there was no meaningful statistically difference in mean absolute prediction error between the OKULIX, SRK-T and Hoffer Q formula. (P = 0.25). Also in each group of implanted IOLs, all three formulas worked with the same accuracy. The prediction error using OKULIX were within ±0.50 diopter in 63.5% of eyes and within ±1.00 diopter in 94.2% of eyes. ConclusionOKULIX ray-tracing IOL power measurements provides reliable and satisfactory postoperative results, which are comparable to other 3rd generation formulas of SRK-T and Hoffer Q.

Femtosecond laser implantation of a 340-degree intrastromal corneal ring segment in keratoconus: Short-term outcomes

To evaluate the short-term outcomes of femtosecond laser-assisted implantation of a 340-degree intracorneal ring (ICR) (Keraring) in patients with keratoconus. Four centers in Iran. Prospective case series. All cases had implantation of the 340-degree ICRafter tunnel creation with a femtosecond laser. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, sphere, cylinder, manifest refraction spherical equivalent (MRSE), mean keratometry (K), steep K, and flat Kwere evaluated preoperatively and 1, 3, and 6months postoperatively. Eighteen eyes of 17 patients were included. The mean follow-up was 4.33months (range 1 to 6months). The mean UDVA improved from 0.95 logarithm of the minimum angle of resolution (logMAR)±0.33 (SD) to 0.53±0.35 logMAR (P=.001) and the mean CDVA from 0.39±0.22 logMAR to 0.26±0.21 logMAR (P=.09). The mean sphere decreased from -5.08±3.74 diopters (D) to -1.67±2.59 D, the mean cylinder from -5.83±2.02 D to -2.72±1.81 D, and the mean MRSE from -8.03±3.88 D to -3.01±2.82 D (P<.001). The mean K decreased from 51.43±3.59 D to 47.42±3.59 D (P<.001). All patients with a preoperative mean K greater than 55.0 D had worse CDVA. Implantation of a 340-degree ICR using femtosecond laser improved the visual, refractive, and topographic parameters in keratoconic patients. The findings indicate that patients with severe keratoconus (mean K >55.0 D) are not good candidates for this type of ICR.

COMBINED FEMTOSECOND LASER ASSISTED CATARACT SURGERY AND PARS PLANA VITRECTOMY

Purpose: Determine the benefits and challenges of combined femtosecond laser-assisted cataract surgery with the Catalys® system (Abbott, Abbott Park, IL) and vitrectomy. Design: Retrospective study Methods: We retrospectively reviewed eight consecutive cases of combined femtosecond laser-assisted cataract surgery with the Catalys® system and vitrectomy by a single surgeon. The University of Minnesota Institutional Review Board provided Expedited Review Approval for this project. Results: The study population was 25% male with mean age of 69.1 years, mean pre-operative intraocular pressure of 14.9 mmHg, and mean best corrected visual acuity of 0.44. All patients completed both portions of the combined procedure. There were no complications from the femtosecond laser portion with the mean vacuum time 163s (range 125-320s). Post-operative findings included intraocular pressure rise (25%), and persistent macular edema (38%). The mean intraocular pressure at month one was 16 mmHg with an improvement in mean best-corrected visual acuity to 0.27 (range 0-0.52, p<0.05). Intraocular lens was centered in all cases, and mean manifest refraction spherical equivalent was -0.77 (range -2.75-0), which was not statistically significantly different than the target spherical equivalent of -0.59 (p=0.24). Conclusions: Combined femtosecond laser-assisted cataract surgery with the Catalys® system and vitrectomy was not associated with significant complications, with an overall improvement in visual acuity.

Comparison of FDA safety and efficacy data for KAMRA and Raindrop corneal inlays.

To provide a side-by-side analysis of the summary of safety and effectiveness data (SSED) submitted to the FDA for the KAMRA and Raindrop corneal inlays for the correction of presbyopia. SSED reports submitted to the FDA for KAMRA and Raindrop were compared with respect to loss of corrected distance visual acuity (CDVA), adverse event rates, induction of astigmatism, retention of contrast sensitivity, stability of manifest refractive spherical equivalent (MRSE), and achieved monocular uncorrected near visual acuity (UNVA) at 24mo. Totally 442/508 of KAMRA patients and 344/373 Raindrop patients remained enrolled in the clinical trials at 24mo. The proportion of KAMRA and Raindrop patients who lost ≥2 lines of CDVA at 24mo was 3.4% and 1%, respectively. The adverse event rate was comparable between the devices. No significant inductions of astigmatism were noted. Both technologies induced a transient myopic shift in MRSE followed by a hyperopic shift and subsequent stabilization. Totally 87% of KAMRA and 98% of Raindrop patients attained a monocular UNVA of J5 (20/40) or better at 24mo, 28% of KAMRA and 67% of Raindrop patients attained a monocular UNVA of J1 (20/20) or better at 24mo. Both devices can be considered safe and effective, however, the results of corneal inlay implantation are mixed, and long-term patient satisfaction will likely depend on subjective expectations about the capabilities of the inlays. Variability in surgical technique and postoperative care within and between the two clinical trials diminishes the comparative power of this article.

Implantable Collamer Lens in the Management of Pseudophakic Ametropia.

To assess Visian Implantable Collamer Lens (ICL) (STAAR Surgical, Monrovia, CA) implantation in the ciliary sulcus to correct pseudophakic ametropia in patients who are not candidates for a keratorefractive procedure. The authors performed a prospective non-comparative case series study of 18 patients (age: 48 to 61 years) with refractive surprise after phacoemulsification. Patients underwent implantation of a piggyback collagen copolymer lens: V4C design in 16 myopic eyes and V4B design in 2 hyperopic eyes. The position and vault of the ICLs were documented at all control visits clinically and with Pentacam (Oculus Optikgeräte, Wetzlar, Germany). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), intraocular pressure (IOP), and endothelial cell count were recorded at baseline and 1 week and 1, 6, 12, and 18 months postoperatively. The MRSE improved from -3.08 ± 2.37 diopters (D) preoperatively to -0.44 ± -0.23 D postoperatively, corrected with a mean ICL power of -3.20 ± 2.90 D. The mean UDVA improved from 1.03 ± 0.12 logMAR preoperatively to 0.05 ± 0.06 logMAR postoperatively (P = .00), whereas CDVA improved from 0.47 ± 0.03 logMAR preoperatively to -0.006 ± 0.02 logMAR (P = .001) postoperatively. None of the cases developed interlenticular opacification throughout the 18-month follow-up. The mean ICL vault measured by Scheimpflug tomography was 451.27 ± 178.5 µm. Acute IOP elevation with anterior uveitis developed in 2 eyes and was controlled by topical steroids and a beta-blocker. Sulcus implantation of the secondary ICL to correct pseudophakic refractive error was safe, predictable, and well tolerated in all studied eyes. [J Refract Surg. 2017;33(8):532-537.].

Intracorneal Inlays for Presbyopia

The purpose of this review is to summarize recent literature and provide clinical pearls for the use of intracorneal inlays for surgical treatment of presbyopia. A preoperative manifest refraction spherical equivalent (MRSE) in the appropriate range for a KAMRA or Raindrop inlay aids with optimization of postoperative visual results. An eye with MRSE of −0.75 is ideal for consideration of KAMRA inlay, whereas plano to +0.50 MRSE tends to have better visual results with Raindrop. Both KAMRA and Raindrop corneal inlays are effective surgical treatment options for presbyopia. Patient selection, preoperative counseling, surgical implantation that is centered, optimized corneal depth, and appropriate postoperative management are vital to patient and surgeon success with the technology.

Correlation of Corneal Biomechanical Stiffness With Refractive Error and Ocular Biometry in a Pediatric Population.

To assess the correlation between corneal biomechanical stiffness and refractive error (RE) in the pediatric population. A total of 733 pediatric eyes were included in the study retrospectively. All eyes underwent corneal tomography (Pentacam), RE assessment, and air-puff deformation (Corvis-ST). Waveform analyses of deformation provided corneal stiffness (CS) and extraocular tissue stiffness (EOS). Eyes were subgrouped into emmetropia [manifest refraction spherical equivalent (MRSE) ∼ 0 D], hyperopia (MRSE > 0 D), myopia I (MRSE between 0 D and -3 D), myopia II (MRSE between -3 D and -6 D), and myopia III (MRSE greater than -6 D) for multivariate analyses. Ocular biometry variables [age, intraocular pressure (IOP), central corneal thickness (CCT), corneal astigmatism, anterior chamber depth, and RE] were used as covariates. The apparent elastic modulus (E) was defined as the ratio of CS and CCT. All groups had similar age, CCT, and IOP (P > 0.05). CS was the only parameter to differ between all the grades of myopia (P < 0.0001). CS was lower by 3.72%, 6.84%, and 10.68% in myopia I, II, and III eyes, respectively, relative to emmetropic eyes. EOS increased by 11.15%, 22.60%, and 28.5%, respectively. Multivariate regression revealed age, IOP, CCT, corneal astigmatism, anterior chamber depth, and RE as significant predictors of CS, with a high coefficient of regression (R = 0.66). Corneal E negatively correlated with the grade of myopia. CS and EOS correlated negatively and positively with the grade of myopia, respectively. Ocular biometry variables were significant predictors of both CS and EOS. The decrease in CS was attributed to that in elastic modulus.

Safety, efficacy and refractive outcomes of LASIK surgery in patients aged 65 or older

Report on the safety, efficiency and refractive outcomes of LASIK surgery in patients aged 65 or older. This study includes a case series of patients ≥65years that underwent corneal refractive surgery during the period June 2010 to June 2015 at Hospital Zambrano Hellion, Monterrey, Mexico. Inclusion criteria were normal topography, central corneal thickness >500μm, preoperative manifest refraction spherical equivalent (MRSE) up to -8.5D and +6.0D, cylinder up to -6.0D, CDVA of 20/25 or better and with no other ocular pathology. A total of 44 eyes (24 patients) were included. Mean age was 67.2±2.1years (range 65-80), with mean follow-up of 12.2±1.3months. Conventional LASIK was performed in 20 patients (group 1, 36 eyes) to improve UDVA (10 eyes myopic LASIK and 26 eyes hyperopic LASIK) and presbyopic LASIK (monovision) in 4 patients (group 2, 8 eyes) to restore near-vision performance. Preoperative MRSE group 1 was myopic: -2.79±1.88D; hyperopic +2.19±1.88D; and +2.10±0.87D in group 2. Preoperative UDVA in group 1 was 0.67±0.30 LogMAR; 0.46±0.18 LogMAR; and Jaeger ≥4 in 90% in group 2. Postoperative MRSE: -0.29±0.86D (myopic LASIK) (p<0.001), +0.34±0.62D (hyperopic LASIK) (p<0.001) and -1.25±0.59D (non-dominant eye) in presbyopic LASIK. Postoperative UDVA in myopic LASIK was 0.15±0.30 (p=0.001) and 0.11±0.11 (p<0.001) for hyperopic LASIK. In group 2, binocular UDVA was 0.16±0.17 (p=0.12) and UNVA was ≥J2 in 100% of the patients. Even though elder patients may present greater LASIK restrictions due to lens and other ocular age-related changes, patients ≥65years that were candidates for conventional and presbyopic LASIK showed satisfactory and safe refractive and visual outcomes.

Photorefractive intrastromal corneal crosslinking for the treatment of myopic refractive errors: Six-month interim findings

To evaluate the safety and efficacy of photorefractive intrastromal corneal crosslinking (CXL) in low myopia. Ruhr University Eye Hospital, Bochum, Germany. Prospective case series. Healthy eyes with myopia or myopic astigmatism had photorefractive intrastromal CXL using the Mosaic system to apply ultraviolet-A (UVA) 365nm (30mW/cm2) irradiance (total calculated UVA dose of 10J/cm2 or 15J/cm2) with riboflavin 0.1% solution. Efficacy was determined by the change in the manifest refraction spherical equivalent (MRSE), uncorrected distance visual acuity (UDVA), and corneal curvature. Safety was determined by the corrected distance visual acuity (CDVA), slitlamp biomicroscopy, endothelial cell count, and adverse events. Twenty-six eyes of 14 patients with a mean age of 30.8years±9.3 (SD) were included. There were statistically significant improvements in UDVA 1, 3, and 6months postoperatively (all P<.001). A significant improvement in CDVA was observed (P=.02). Improvements in the mean manifest sphere and MRSE versus baseline were noted at all visits (P<.001), with a mean change of 0.99±0.47 diopter (D) and 0.97±0.48 D, respectively, by 6months postoperatively. Significant reductions in corneal curvature versus baseline occurred at all follow-up visits (all P<.05). At1month, there were no significant changes in the endothelial cell density (P=.282) or number of cells (P=.069). No safety issues or complications were reported. The findings show that patterned CXL using a custom CXL system is safe and effective for reducing myopic refractive error.

Comparison of visual effects of FS-LASIK for myopia centered on the coaxially sighted corneal light reflex or the line of sight.

To compare visual quality after femtosecond laser in situ keratomileusis (FS-LASIK), between the coaxially sighted corneal light reflex (CSCLR) group and conventional ablation line of sight (LOS) group. In total, 243 eyes (122 patients) were treated with centration on the CSCLR (visual axis) and 238 eyes (119 patients) treated with centration on the pupil center (LOS). Postoperative outcomes [uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA)], safety index, efficacy index, refractive outcome, ablation center distance from the visual axis, corneal high-order aberrations, subjective discomfort glare and shadowing incidence rate, and contrast sensitivity at 1, 3, and 6mo were measured and compared. The mean age was 27.77±7.1y in the CSCLR group and 26.03±7.70y in the LOS group. Preoperatively, the manifest refraction spherical equivalent (MRSE) was -6.68±2.60 D in the CSCLR group and -6.65±2.68 D in the LOS group. The postoperative UCVA, BSCVA, MRSE (-0.03±0.263 D in the CSCLR group, -0.05±0.265 D in the LOS group), efficacy index (1.04, 1.03), and safety index (1.09, 1.08) were not significantly different between the groups (all P>0.05). In total, 3% lost one line and more of BSCVA in the CSCLR group, as 9% in the LOS group postoperatively (P<0.05). The ablation center deviation was 0.20±0.15 mm from the visual axis (Pentacam system default setting; range, 0-0.75 mm) in the CSCLR group, and 0.43±0.22 mm (range, 0-1.32 mm) in the LOS group (P<0.0001). Statistically significant greater augmentation of total corneal higher-order aberrations (0.15±0.10 µm and 0.20±0.12 µm respectively, P=0.03) and vertical and horizontal coma (P<0.0001) were noted in the LOS group. Subjective discomfort glare and shadowing incidence rates were 8.59% and 17.5% in the CSCLR and LOS groups, respectively (P<0.05). The 1-month postoperative contrast sensitivity visual acuity in the CSCLR group was significantly higher than that in the LOS group on contrast (100%, 25%, 10%) with a dark background, but there was no significant difference between the groups at 3 or 6m. Myopic LASIK centered on the CSCLR achieves significantly lower induction of loss of BSCVA, corneal high-order aberrations, and lower risk of subjective discomfort glare and shadowing, and lower decline in early contrast sensitivity by comparison with centration on the LOS, giving advantages in visual quality postoperatively.

V4B implantable collamer lens versus Intacs corneal rings to manage anisometropic myopic amblyopia in children

ObjectiveTo compare the safety and efficacy of phakic intraocular lens (PIOL) versus intrastromal corneal ring segments (Intacs), for correcting high myopic anisometropia in amblyopic children. DesignNonrandomized prospective multi-center study. ParticipantsThirty children, aged between 4 and 12 years, with unilateral high myopic anisometropic amblyopia were included in this study. MethodsPatients who were prospectively subdivided into group A, with mean preoperative manifest refraction spherical equivalent (MRSE) of −12.96 ± 4.17 D, underwent unilateral phakic posterior chamber intraocular lens implantation. Patients with mean preoperative MRSE of −8.60 ± 1.16 D in group B were treated by Intacs corneal rings. Pre- and postoperative visual acuity, ocular examination, stereoacuity, axial biometry measurements, cycloplegic refraction, and endothelial cell counts were performed in all patients. ResultsGroup A revealed prevention of amblyopia with improvement in spectacle-corrected distance visual acuity, where 4–6 lines were achieved in 77% of children, 2–3 lines in 4%, and just 0–1 lines restricted to 19% of children. Improvement in stereoacuity was noted in 93.33% of group A cases, whereas group B showed fewer cases of successfully improved vision, with 4–6 lines in 70% of children, 2–3 lines in 3%, and just 0–1 lines restricted to 27% of children. Improvement in stereoacuity was noted in 86.66% of cases. Two cases of cataract and 1 case of glaucoma with 1 case of uveitis were noted in the implantable contact lens (ICL) group. ConclusionsPosterior chamber PIOLs or Intacs may provide a safe alternative in treating anisometropic myopic patients. Intacs implantation is safer with fewer complications than ICL. However, ICL implantation is advantageous over the corneal ring segment procedure owing to the wide range of errors to correct.

Comparison of laser in situ ketatomileusis and photorefractive keratectomy for myopia using a mixed-effects model.

PurposeTo compare the results of laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) for myopia using a mixed-effects model.MethodsThis comparative retrospective study was conducted in 1,127 eyes of 579 patients after LASIK and 270 eyes of 144 patients after PRK who had two or more postoperative follow-ups after 3 months. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refractive spherical equivalent (MRSE), percentage of eyes within ± 0.5 diopters (D) and ± 1.0 D of targeted refraction, and central corneal thickness were compared between PRK and LASIK groups using a mixed-effects model.ResultsCompared with the LASIK group, UCVA in the PRK group was significantly worse in the initial year but was significantly better after 4 years. The average BSCVA was not significantly different between the LASIK and PRK groups after 4 years. The average gain of BSCVA in the PRK group was significantly larger than that of the LASIK group after 2 years. MRSE in the LASIK and PRK groups showed a gradual myopic shift until 6 years after surgery. After 6 years, MRSE in the PRK group remained stable whereas MRSE in the LASIK group continued a myopic shift. The percentages of eyes within ± 0.5 D or ± 1.0 D in the LASIK group were significantly higher than those in the PRK group at 3 months but were significantly lower than those in the PRK group at 10 years.ConclusionsPRK for myopia shows better efficacy than LASIK for myopia after 4 years.

Enhancement after Small-Incision Lenticule Extraction: Incidence, Risk Factors, and Outcomes

To report the incidence, risk factors, and outcomes of enhancement after small-incision lenticule extraction (SMILE). Retrospective cohort study. Five hundred twenty-four eyes of 307 patients who underwent SMILE at Singapore National Eye Center between February 2012 and March2016. The data collected included patient age at primary SMILE, gender, race, preoperative and postoperative manifest refraction spherical equivalent (MRSE), preoperative and postoperative uncorrected distance visual acuity and corrected distance visual acuity, the occurrence of suction loss during the procedure, and the need for enhancement. All enhancements were carried out by performing an alcohol-assisted photorefractive keratectomy (PRK) procedure with application of mitomycin C (MMC). Incidence, prevalence, preoperative and intraoperative risk factors for enhancement, and outcomes after enhancement. The prevalence of enhancement was 2.7%, and 71.4% eyes had enhancement within 1 year of primary SMILE. The incidence of enhancement was 2.1% and 2.9% at 1 and 2 years, respectively. Age older than 35 years, preoperative MRSE more than-6.00 diopters (D), preoperative myopia more than 6.00 D, preoperative astigmatism more than 3.00 D, and intraoperative suction loss were significant risk factors for enhancement after SMILE after adjusting for all other covariates (odds ratios, 5.58, 4.80, 1.41, 3.06, and 2.14, respectively; P= 0.004, 0.021, 0.022, 0.002, and 0.020, respectively). In the patients who underwent bilateral SMILE, the first-operated eye had a marginal trend toward significance for enhancement (P= 0.054). There was no gender or racial difference. In the 14 eyes requiring enhancement, the uncorrected distance visual acuity before enhancement ranged from 20/80 to 20/25, and the mean attempted enhancement spherical equivalent was-0.50±0.86 D. The uncorrected distance visual acuity improved in most patients (92.9%) after enhancement. The 2-year incidence of enhancement after SMILE was 2.9%. Risk factors associated with enhancement included older age at SMILE procedure, greater preoperative MRSE, greater preoperative myopia, greater preoperative astigmatism, and the occurrence of intraoperative suction loss. Clinical outcomes of using PRK with application of MMC for enhancement were good.

Artisan iris-fixated intraocular lens implantation in combination with pupilloplasty—correction of aphakia with pathologically large pupil and insufficient capsular support

ObjectiveThe aim of this study was to report the efficacy and safety of applying pupilloplasty in combination with Artisan iris-fixated intraocular lens (IOL) implantation in the treatment for aphakia with pathologically large pupil and insufficient capsular support. DesignThe study was a retrospective case series. ParticipantsTwenty-six aphakic eyes with pathologically large pupil and insufficient capsular support (from 26 patients) were included in the study. MethodsThe study patients underwent pupilloplasty in combination with Artisan iris-fixated IOL implantation. Follow-up appointments were scheduled at 1 week and at 1, 3, and 6 months postoperatively. ResultsThe mean uncorrected visual acuity was significantly improved from logMAR 1.15 ± 0.29 to logMAR 0.37 ± 0.17, and the mean manifest refraction spherical equivalent was significantly decreased from 12.07 ± 2.20 D to –0.69 ± 0.70 D at 6 month after surgery (p < 0.05). The pupil diameter decreased significantly, from 5.7 ± 1.1 mm preoperatively to 4.5 ± 0.8 mm at 6 months after pupilloplasty (p < 0.05). Patients experienced less photophobia postoperatively. The safety parameters, including endothelial cell count, intraocular pressure, corneal astigmatism, best-corrected visual acuity, and central corneal thickness, showed no significant differences in values before and after surgery. ConclusionsThe Artisan iris-fixated IOL implantation in combination with pupilloplasty can be used as an alternative way to correct aphakia with pathologically large pupil and insufficient capsular support.