Outcomes of Astigmatic Correction with and without Two Different Cyclotorsion Compensation Methods in Small Incision Lenticule Extraction Surgery.

PURPOSE: To compare the astigmatic correction outcomes of small incision lenticule extraction (SMILE) surgery with or without two different cyclotorsion compensation methods. METHODS: This is a prospective randomized clinical trial. Patients with myopic astigmatism that underwent SMILE surgery were randomly divided into static cyclotorsion compensated group (SCC group), slit-lamp group and control group. In the SCC and slit-lamp groups, the intraoperative cyclotorsion was manually compensated with different limbal marking methods. In the control group, the cyclotorsion was not compensated. Visual acuity and manifest refraction were measured preoperatively and postoperatively. Astigmatic outcomes were estimated with vector analysis. RESULTS: A total of 94 eyes from 94 patients were analyzed postoperatively at the 3-month follow-up. Their mean preoperative cylinder was -1.56±0.86 D (range: -4.25 to -0.25 D). The mean preoperative spherical equivalent was -5.95±1.72 D (range: -10.50 to -2.75 D). All groups showed favorable results in the correction of myopic astigmatism. No statistically differences were found among three groups in postoperative visual acuity, refractive outcomes or vector parameters. CONCLUSION: Cyclotorsion compensation with two different manual limbal marking methods was helpful in aligning the surgical position in SMILE, but it was not as effective as expected for the correction of myopic astigmatism under well controlled surgical positioning.

International Multicenter, Myopic and Myopic Astigmatism Femto LASIK, Customized by Automated Ray-Tracing Ablation Profile Calculation: A Postmarket Study.

Purpose: To assess the safety and efficacy of a customized ablation treatment (InnovEyes) to correct myopia and myopic astigmatism with femtosecond laser-assisted in situ keratomileusis (Femto LASIK). Patients and Methods: In this prospective, nonrandomized, multicenter study, 113 patients (225 eyes) with preoperative myopia less than -9.0 diopters (D) and astigmatism 0 to -4.0 D (based on InnovEyes refraction) underwent wavefront, tomography, and biometry assessment using a single diagnostic device (InnovEyes sightmap). These data were imported and used unmodified by the InnovEyes algorithm to automatically calculate and optimize correction of lower- and higher­order aberrations (HOAs) treated by the EX500 ablation profile. Visual acuity, refractive error, HOAs, and patient satisfaction were evaluated over 3 months. Results: A total of 106 patients (212 eyes) completed the study and were included in the analysis. Mean preoperative manifest refraction spherical equivalent (MRSE) was -3.38±1.76 D. At Month 3, uncorrected distance visual acuity was 20/20 or better in 208/212 (98.1%) eyes, and it was the same as, or better than, the preoperative best-corrected distance visual acuity (CDVA) in 162/212 (76.4%) eyes; 76/212 (35.8%) eyes gained ≥1 line of CDVA. MRSE was within ±0.5 D in 195/212 (92.0%) eyes. Additionally, 201/209 (96.2%) eyes had no change (defined as a change between -0.1 µm and 0.1 µm, inclusive) in HOAs, and 105/106 (99.1%) patients reported to be satisfied with the results. Conclusion: Customizing ray-tracing Femto LASIK with this platform appeared safe and effective in correcting myopic astigmatism and also achieved a significant percentage of eyes gaining lines of vision, potentially by addressing HOAs, along with a consistently high level of patient satisfaction.

Clinical effect of cross positioning method for correcting low and moderate astigmatism during small incision lenticule extraction / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the clinical outcomes of using the cross-positioning method for correcting low and moderate astigmatism during small incision lenticule extraction(SMILE)surgery with Alpins vector analysis.METHODS: A total of 50 patients(81 eyes)with low and moderate astigmatism with the rule ≤1.50 D who underwent SMILE surgery at the laser myopia treatment center of Xi'an No.1 Hospital from May 2022 to November 2022 were included in the prospective randomized controlled study, and they were divided into two groups according to the random table, with 25 case(41 eyes)in cross-positioning group and 25 cases(40 eyes)in control group. In the cross-positioning group, the patients' head position was adjusted based on the cross intersection lines before the standard SMILE procedure, aligning the lateral canthi with the horizontal line and the midpoint of the eyebrows and the nose bridge with the vertical line. Postoperative visual acuity and refractive results at 3 mo were observed in both groups, and astigmatic changes were analyzed and evaluated using the Alpins vector analysis method.RESULTS: During the follow-up period, 6 cases(11 eyes)in the cross-positioning group were lost to follow-up, while in the control group, 8 cases(14 eyes)were lost to follow-up, with 19 cases(30 eyes)and 17 cases(26 eyes)finally included in the cross-positioning group and the control group, respectively. At 3 mo postoperatively, the uncorrected visual acuity(UCVA)of both groups' operated eyes was ≥1.0, and no serious complications occurred, with no significant differences in UCVA, best corrected visual acuity(BCVA), spherical power, and spherical equivalent between the cross-positioning group and the control group(all P>0.05). The cylindrical power in the cross-positioning group was 0.00(0.00, 0.00)D, which was lower than -0.13(-0.50, 0.00)D in the control group(P=0.01). The vector analysis results showed that the difference vector(DV)in the cross-positioning group was lower than that in the control group [0.00(0.00, 0.00)vs 0.13(0.00, 0.50), P=0.01], and the index of success(IOS)was better than that of the control group [0.00(0.00, 0.00)vs 0.18(0.00, 0.77), P<0.01]. At 3 mo postoperatively, 26(87%)and 15(58%)eyes in the cross-positioning group and control groups achieved an angle of error(AE)within ±5°, respectively.CONCLUSION: The cross positioning method was used to calibrate the patients' head position during SMILE surgery, which reduced the axial position error and improved the accuracy of SMILE in correcting low and moderate astigmatism.

Comparing high and low energy outcomes on day one for SmartSight myopic-astigmatism treatments with the SCHWIND ATOS: a retrospective case series.

BACKGROUND: Impact of low energy asymmetric spacings vs. high energy symmetric spacings on the immediate/early (postoperative day 1 (POD1)) outcomes of SmartSight lenticule extraction for myopic astigmatism with a new femtosecond laser system. METHODS: The first 112 eyes of 56 patients consecutively treated using low energy asymmetric spacings (Group A; Study group) were compared at POD1 to the last 112 eyes of 56 patients consecutively treated using high energy symmetric spacings (Group S; Controls). Mean age of the patients was 28 ± 5 years with a mean spherical equivalent of -4.41 ± 1.76 diopters (D) and a mean magnitude of refractive astigmatism of 0.89 ± 0.82 D. RESULTS: Laser Energy was -25 ± 1nJ lower for asymmetric treatments (p < .0001); Spot and Track distances were + 0.7 ± 0.1 µm larger and -0.8 ± 0.1 µm tighter for asymmetric treatments, respectively (p < .0001 for both). At POD1, astigmatism was -0.08 ± 0.02D lower for asymmetric treatments (p < .0003); uncorrected and corrected visual acuities (UDVA and CDVA, respectively) were -0.03 ± 0.01logMAR better for asymmetric treatments (p < .0007); differences between postop UDVA and preop CDVA along with change in CDVA were + 0.3 ± 0.1lines better for asymmetric treatments (p < .0003). CONCLUSIONS: Lenticule extraction treatment using SmartSight is safe and efficacious already at POD1. Findings suggest that low energy asymmetric spacings may further improve the immediate and short-term outcomes of SmartSight lenticule extraction in the treatment of myopic astigmatism compared to conventional settings (high energy symmetric spacings).

Cationic nanoemulsion vs. 0.15% sodium hyaluronate artificial tears in the healing process following modern surface keratorefractive surgery.

PURPOSE: The aim of this study was to investigate the influence of artificial tears containing either cationic nanoemulsion (CCN) or sodium hyaluronate artificial tears (SH) on early postoperative healing after modern surface refractive surgery. MATERIALS AND METHODS: In this multicenter, prospective, double-masked, parallel-group (1:1), comparative study, 129 patients (n = 255 eyes) were randomized to receive CCN (n = 128) or SH (n = 127) as an adjuvant treatment after either transepithelial photorefractive keratectomy (transPRK) or Epi-Bowman keratectomy (EBK). The patients' perspectives were gathered using the Ocular Surface Disease Index (OSDI) questionnaire, and uncorrected (UCVA), and corrected (BCVA) visual acuity were assessed before and one week and one month after the procedure. In addition, corneal epithelization and subjective assessment of visual blur and eye irritation on drop instillation were assessed at one week postoperatively. RESULTS: No statistically significant differences were found between two groups in age, spherical equivalent refractive error, UCVA, BCVA or OSDI scores before the procedure. There was also no difference between groups in UCVA one week and one month after the procedure. However, statistically significantly lower OSDI scores were found one week and one month after the procedure in the CCN group. Moreover, blurred vision after use of the eye drops was observed less frequently in the CCN group than in the SH group. CONCLUSIONS: The CCN and SH groups had similar postoperative UCVA. However the significantly lower OSDI scores and less frequently blurred vision after application of the eye drops in the CCN group suggest better subjective outcomes in this group.

The effects of programmed optical zones on achieved corneal refractive power with myopic astigmatism after small incision lenticule extraction (SMILE): a vector analysis.

PURPOSE: To evaluate the effects of different programmed optical zones (POZs) on achieved corneal refractive power (CRP) with myopic astigmatism after small incision lenticule extraction (SMILE). METHODS: In total, 113 patients (113 eyes) were included in this retrospective study. The eyes were divided into two groups according to POZ: group A (6.5, 6.6, and 6.7 mm, n = 59) and group B (6.8, 6.9, and 7.0 mm, n = 54). Fourier vector analysis was applied to evaluate the error values between the attempted and achieved corneal refractive power (CRP). Alpins vector analysis was used to calculate surgically induced astigmatism (SIA), difference vector (DV), magnitude of error (ME), and astigmatism correction index (ACI). Multivariate regression analysis was performed to assess potential factors associated with the error values. RESULTS: The error values in the group with large POZ were closer to zero, and significantly associated with the POZ at 2 and 4 mm of the cornea (ß = - 0.50, 95% confidence interval [CI] [- 0.80, - 0.20]; ß = - 0.37, 95% CI [- 0.63, - 0.10], P < 0.05, respectively). For the correction of astigmatism, the values of SIA, ME, and ACI were lower in group B than in group A (P < 0.05). The fitting curves between TIA and SIA were y = 0.83x + 0.19 (R2 = 0.84) and y = 1.05x + 0.04 (R2 = 0.90), respectively. CONCLUSIONS: Smaller POZs resulted in higher error values between the achieved- and attempted-CRP in the SMILE procedure, which should be considered when performing surgery.

Twelve-month outcomes of a new refractive lenticular extraction procedure

Background: To evaluate the 12-month refractive and visual outcomes of Small Incision Guided Human-cornea Treatment (SmartSight®, SCHWIND eye-tech-solutions, Kleinostheim, Germany) in the treatment of myopia corrections with low to moderate astigmatism with the use of a new femtosecond laser system.Methods221 eyes of 114 patients consecutively treated with SmartSight lenticule extraction were assessed. The mean age of the patients was 28±6 years at the time of treatment with a mean spherical equivalent refraction of -6.26±2.17D and mean astigmatism of 0.92±0.68D. Monocular corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA) were assessed pre- and post-operatively. Refractive changes have been determined in terms of changes in refraction, as well as changes in keratometric readings. The changes in central epithelial thickness have been determined.ResultsAt twelve months post-operatively, mean UDVA was 20/21±2. Spherical equivalent showed a residual refraction of +0.48±0.31D with refractive astigmatism of 0.13±0.18D postoperatively. There was a slight decrease of -0.1 Snellen lines at 12-months follow-up. The same correction was determined using changes in refraction, as well as changes in keratometric readings. The central epithelial thickness increased by +3±2µm. Spherical equivalent correction within ±0.50D was achieved in 199 eyes (90%), and cylindrical correction in 221 (100%). Preoperative corrected distance visual acuity (CDVA) was 20/20 or better in 213 eyes (96%), and postoperative uncorrected (UDVA) was 20/20 or better in 205 eyes (93%). No eye had lost two or more Snellen lines of CDVA.ConclusionsMyopic astigmatism correction with SmartSight provided good results for efficacy, safety, predictability, and visual outcomes at the twelve months of follow up. The central epithelial thickness barely increased by 3±2µm. (AU)

Twelve-month outcomes of a new refractive lenticular extraction procedure.

BACKGROUND: To evaluate the 12-month refractive and visual outcomes of Small Incision Guided Human-cornea Treatment (SmartSight®, SCHWIND eye-tech-solutions, Kleinostheim, Germany) in the treatment of myopia corrections with low to moderate astigmatism with the use of a new femtosecond laser system. METHODS: 221 eyes of 114 patients consecutively treated with SmartSight lenticule extraction were assessed. The mean age of the patients was 28±6 years at the time of treatment with a mean spherical equivalent refraction of -6.26±2.17D and mean astigmatism of 0.92±0.68D. Monocular corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA) were assessed pre- and post-operatively. Refractive changes have been determined in terms of changes in refraction, as well as changes in keratometric readings. The changes in central epithelial thickness have been determined. RESULTS: At twelve months post-operatively, mean UDVA was 20/21±2. Spherical equivalent showed a residual refraction of +0.48±0.31D with refractive astigmatism of 0.13±0.18D postoperatively. There was a slight decrease of -0.1 Snellen lines at 12-months follow-up. The same correction was determined using changes in refraction, as well as changes in keratometric readings. The central epithelial thickness increased by +3±2µm. Spherical equivalent correction within ±0.50D was achieved in 199 eyes (90%), and cylindrical correction in 221 (100%). Preoperative corrected distance visual acuity (CDVA) was 20/20 or better in 213 eyes (96%), and postoperative uncorrected (UDVA) was 20/20 or better in 205 eyes (93%). No eye had lost two or more Snellen lines of CDVA. CONCLUSIONS: Myopic astigmatism correction with SmartSight provided good results for efficacy, safety, predictability, and visual outcomes at the twelve months of follow up. The central epithelial thickness barely increased by 3±2µm.

Small Incision Lenticule Extraction (SMILE) and Laser in Situ Keratomileusis (LASIK) Used to Treat Myopia and Myopic Astigmatism: A Systematic Review and Meta-analysis of Randomized Clinical Trials.

PURPOSES: The purpose of this meta-analysis is to systematically compare the safety, efficacy, and predictability of small incision lenticule extraction (SMILE) and laser in situ keratomileusis (LASIK). METHODS: This study covered the data searched from the PubMed, the EMBASE and the Cochrane Library. The Cochrane Handbook was also referred to as evaluating the quality of the included studies. In addition, this meta-analysis was performed using Revman 5.4 software. RESULTS: A total of 11 randomized controlled trails (RCTs) were included. The proportion of eyes with refraction within ±0.5D was higher in LASIK group compared with SMILE group (RR, 0.91; 95% CI, 0.83 to 0.99; p = .04). The spherical aberration (SA) was smaller in SMILE group compared with LASIK group (RR, -0.12; 95% CI, -0.23 to -0.01; p = .04). There were no significant differences between two groups with regard to final mean refractive spherical equivalent (SE) (MD, -0.04; 95% CI, -0.12 to 0.03; p = .22), proportion of eyes losing one or more lines of corrected distance visual acuity (CDVA) (RR, 1.14; 95% CI, 0.58 to 2.27; p = .70), proportion of eyes with uncorrected distance visual acuity (UCVA) of 20/20 or better (RR, 0.99; 95% CI, 0.94 to 1.05; p = .71), postoperative mean logMAR UCVA (MD, 0.01; 95% CI, -0.00 to 0.03; p = .13), postoperative refraction within ±1.0D (RR, 1.00; 95% CI, 0.98 to 1.02; p = .60), postoperative astigmatism within ±0.25, 0.5 and 1.0D (RR, 0.80, 0.99, 1.00; 95% CI, 0.35 to 1.83, 0.94 to 1.05, 0.98 to 1.02; p = .60, 0.86, 0.87), postoperative higher order aberrations (HOAs) (RR, 0.00; 95% CI, -0.16 to 0.16; p = .99). CONCLUSION: For predictability, LASIK was superior to SMILE. There were comparably safety and efficacy for the correction of myopia and myopic astigmatism in SMILE and LASIK. SA was smaller after SMILE than after LASIK.

Clinical analysis of functional optical zone after transepithelial photorefractive keratectomy in patients with different degrees of myopic astigmatism / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the effect of preoperative degrees of myopic astigmatism and anterior corneal curvature on the functional optical zone(FOZ)after transepithelial photorefractive keratectomy(TransPRK).METHODS: Retrospective study was conducted on 78 patients(130 eyes)with myopia and myopic astigmatism who underwent TransPRK, and they were divided into control group(cylinder 0D), moderate astigmatism group(-0.50～-2.00D)and high astigmatism group(&#x003E;-2.00～&#x003C;-6.00D). The FOZ was measured and compared among the three groups 6mo after operation. The correlations between attempted correction, anterior corneal curvature, corneal aberrations, Q value, and the FOZ were analyzed.RESULTS: At 6mo after operation, the mean FOZ was 5.16±0.12mm in the control group, 5.29±0.23mm in the moderate astigmatism group, and 5.49±0.23mm in the high astigmatism group(P&#x003C;0.001), and the FOZ of the high astigmatism group was significantly higher than moderate astigmatism and control group(P&#x003C;0.05, P&#x003C;0.001); Pearson correlation analysis showed that the changes in spherical equivalent, total corneal higher-order aberrations(HOAs), coma, and spherical aberration were all negatively correlated with FOZ(all P&#x003C;0.05); and FOZ positively correlated with changes in the steep curvature(K2), mean curvature(Km), corneal astigmatism, and Q value(all P&#x003C;0.01). Multiple linear regression analysis showed that there was still positive correlation between preoperative K2 and FOZ after adjusting for other risk factors(P&#x003C;0.001).CONCLUSION: Patients with high astigmatism can obtain a larger FOZ and less induced coma after TransPRK. A larger FOZ can be achieved in eyes with steeper keratometry.

SMILE after DALK to reduce residual refraction: two-year results.

PURPOSE: To determine the two-year results of small incision lenticule extraction (SMILE) for correcting post-keratoplasty myopia and myopic astigmatism. METHODS: In this case-series study, 10 eyes of 10 patients with a 6- to 10-year history of successful deep lamellar keratoplasty (DALK) underwent SMILE using the VisuMax laser platform. Ophthalmologic examinations and visual acuity and refraction measurement were taken pre- and 1, 3, 6, 12, and 24 months postoperatively. The Pentacam and Sirius imaging were done in the first and last follow-up sessions. RESULTS: The mean age of the patients was 39.60 ± 7.86 years. Six subjects were male. Two years after SMILE, the mean improvement in UDVA and CDVA was 3.60 ± 1.84 (P < 0.001) and 1.60 ± 2.91 (P = 0.231) LogMAR, respectively. The mean decrease in spherical equivalent, spherical error, and cylinder power was 1.92 ± 1.96 diopter (D) (P = 0.013), 0.70 ± 3.05D (P = 0.213), and 2.42 ± 2.91D (P = 0.024), respectively. The vector mean target-induced astigmatism, surgical-induced astigmatism, and difference vector were 1.30D@44˚, 1.11D@24˚, and 0.86D@73˚, respectively. Two years after SMILE, vertical coma, horizontal coma, and spherical aberration increased by 0.44 ± 0.51, 0.23 ± 0.32, and 0.02 ± 0.16 µm, respectively, (all P > 0.05) while trefoil reduced by 0.29 ± 0.75 µm (P = 0.428). CONCLUSION: SMILE can be an effective procedure for reducing refraction and astigmatism after DALK in patients with moderate myopia and moderate to severe astigmatism and improves the visual acuity in these patients. Axis rotation during surgery may result in under-correction of astigmatism. Refinement of SMILE treatment nomogram for post-DALK cases seems necessary.

Influence of Ocular Residual Astigmatism on the Correction of Myopic Astigmatism by Toric Implantable Collamer Lens: A Comparative Study With Femtosecond Laser Small Incision Lenticule Extraction.

Purpose: To evaluate the influence of the origin of astigmatism on the correction of myopic astigmatism by toric implantable collamer lens (TICL) and compare it with femtosecond laser small incision lenticule extraction (SMILE). Methods: Ocular residual astigmatism (ORA) was determined by vector analysis using manifest refraction and Scheimpflug camera imaging of the anterior cornea. One-to-one matching between the TICL and SMILE groups was performed by preoperative manifest refractive astigmatism (RA) and ORA, tolerating a maximum difference of 0.50 diopter (D) for RA and 0.25 D for ORA. Patients of each group were further divided into groups according to ORA (high > 1.0 D; low ≤ 1.0 D). The baseline and 12-month postoperative data were analyzed. Data are expressed as mean ± standard deviation (SD). A value of p less than 0.05 was considered statistically significant. Results: For the TICL group, no significant differences in the postoperative RA, safety index, efficacy index, index of success (IOS), correction index (CI), and angle of error (AOE) were found between high (n = 36) and low ORA (n = 36) groups (Mann-Whitney U test, p > 0.05). For the SMILE group, the postoperative RA (high: -0.67 ± 0.43 D, low: -0.39 ± 0.29 D, Mann-Whitney U test, p = 0.003) and IOS (high: 0.50 ± 0.43, low: 0.25 ± 0.23, Mann-Whitney U test, p = 0.003) were greater in the high ORA group. When comparing TICL and SMILE groups, the mean postoperative RA (TICL: -0.48 ± 0.29 D, SMILE: -0.67 ± 0.43 D, Mann-Whitney U test, p = 0.03) and IOS (TICL: 0.32 ± 0.23, SMILE: 0.50 ± 0.43, Mann-Whitney U test, p = 0.03) were significantly higher in the SMILE group when the ORA was >1.0 D. Conclusion: Both TICL and SMILE are effective in correcting myopic astigmatism. ORA has a lesser effect on TICL than on SMILE.

Effect of eye laterality on correction of myopic astigmatism with small incision lenticule extraction (SMILE) using vector analysis.

PURPOSE: To compare the vector analysis, visual, and refractive outcomes after myopic astigmatic correction using SMILE between the right and left eyes. METHODS: This is a retrospective study including 41 right and 40 left eyes that underwent SMILE for correction of myopic astigmatism greater than 0.75 diopters (D) with a follow-up of at least 3 months. Vector analysis for astigmatic correction was done. Visual and refractive parameters were compared between both groups by measuring mean postoperative logMAR uncorrected distance visual acuity, mean postoperative spherical equivalent (SE), cylinder, and refractive predictability in terms of SE and cylindrical correction. Efficacy and safety of SMILE were also determined. RESULTS: No significant difference was found between vector outcomes except for angle of error (AE). The right eye group yielded a negative mean AE (- 2.71 ± 5.35), while the left eye group yielded a positive mean AE (0.23 ± 9.60). Correction index, magnitude of error and refractive predictability of cylindrical correction showed undercorrection of astigmatism in both groups. The right eye group showed lower predictability for higher cylindrical correction. Visual outcomes were similar for both eyes. CONCLUSION: Rotational errors account for vectorial outcome differences between right and left eyes. Despite achieving good visual and refractive outcomes with low cylinder correction, the tendency to undercorrect between eyes due to this error may be more evident when treating higher amounts of astigmatism. More careful preoperative control for cyclotorsion is warranted for right eyes compared to left eyes.

Femtosecond LASIK for the correction of low and high myopic astigmatism.

INTRODUCTION: Higher preoperative myopic astigmatism is associated with a higher probability of retreatment due to patient dissatisfaction as a result of residual cylindrical error. Nonetheless, retreatment is safe and the final clinical results are comparable to those of patients with lower preoperative astigmatism who were satisfied with the primary treatment. Our purpose is to compare the efficacy and safety of femtosecond LASIK (FS-LASIK) for the refractive correction of patients with low (< 1.5 Diopters (D) versus high (≥ 1.5 D) myopic astigmatism. METHODS: Retrospective observational study of 841 eyes of 825 eligible patients treated with FSLASIK for the correction of simple or compound myopic astigmatism. Outcome measures included residual error, best corrected and uncorrected distance visual acuity (BCVA and UCVA), efficacy and safety 3 months after the primary procedure or the retreatment. RESULTS: Of 841 eyes in total, 432 (51.37%) had < 1.5 D (Group 1) and 409 (48.63%) had ≥ 1.5 D (Group 2) preoperative myopic astigmatism. The efficacy index of primary treatment was 0.94 ± 0.18 in Group 1 and 0.89 ± 0.22 in Group 2 (P = 0.001). Of 138 eyes (16.41%) that were retreated due to dis-satisfaction related to residual refractive error, 28 belonged to Group 1 (6.5%) and 110 (26.9%) to Group 2 (P < 0.001). Following retreatment, small but statistically significant differences in the residual mean postoperative cylinder (-0.08 ± 0.24 vs -0.27 ± 0.46 D, P = 0.001) and UCVA (1.11 vs 0.96, P = 0.0001) were detected for Groups 1 and 2, respectively. However, there were no statistically significant differences in the safety and efficacy indices. CONCLUSION: Following FS-LASIK, eyes with myopic astigmatism ≥ 1.5 D have approximately four times more chances of undergoing retreatment due to dis-satisfaction caused by residual refractive error compared to eyes with myopic astigmatism < 1.5 D. However, the clinical results after retreatment are highly satisfactory and comparable in both groups.

One year outcomes after small incision lenticule extraction ReLEX in the correction of myopia and myopic astigmatism.

PURPOSE: To report the visual and refractive outcomes of small incision lenticule extraction ReLEX (SMILE) technique using VisuMax femtosecond laser in myopia and myopic astigmatism patients. MATERIAL AND METHODS: A non-randomized clinical study has been conducted on patients with myopia and myopic astigmatism who underwent ReLEX SMILE technique, using the Zeiss VisuMax Laser system (Carl Zeiss Meditec AG, Jena, Germany) at Oculens Clinic, Cluj-Napoca, Romania. Patients older than 18 years, with ocular astigmatism up to -5 diopters (D), spherical equivalent up to -10.00 D, corrected distance visual acuity (CDVA) of 0.3 or better before the surgery, stable refraction for one year, and with a minimum calculated post operator residual stromal bed of 250µ were included in the study. RESULTS: The study involved a total of 25 myopic eyes (median of sphere diopters equal with -4D) and 67 myopic astigmatic eyes (median of cylinder diopters equal with -1.5 D). The mean refractive spherical equivalent (MRSE) on patients with myopic eyes reduced from -4.25D (median) to -0.5D at one month follow-up, -0.25 D at 6 and 12 months. The mean refractive spherical equivalent (MRSE) on patients with astigmatic myopic eyes reduced from-6.25 D to -0.67 D at one month, -0.62 D at six and twelve months. The value of sphere decreased postoperatively on myopic eyes with a median of -0.25D at one, six and twelve months. The value of cylinder decreased postoperatively on myopic astigmatic eyes with a median of -0.50 D at one month, -0.25 D at six months and -0.50 D at 12 months. At 6 and 12 months, 20 (80.0%) of myopic eyes were maintained within ±0.5 D and 22 (88.0%) with ±1D. On both groups (myopic eyes and myopic astigmatic eyes), statistically significant differences were observed when the keratometric baseline values were compared to each follow-up (P-values < 0.0001), without any significant differences between follow-ups (P-values>0.15). At 1-month follow-up, uncorrected distance visual acuity (UDVA) was better than or equal to 0.5 in 88.0% of myopic eyes and 82.1% of myopic astigmatic eyes. UDVA remained stable in all cases of myopic eyes at six months and the percentage increased at 92.0% in myopic eyes. UDVA slightly increased at 6-months (85.1%) and remained at the same value at 12-months in myopic astigmatism eyes. CONCLUSIONS: SMILE proved an effective and safe refractive corneal procedure and provided a predictable and stable correction of myopia and myopic astigmatism. SMILE technique demonstrated very good outcomes in terms of keratometric, cylinder, spherical measurements.

Toric Implantable Collamer Lens for the Treatment of Myopic Astigmatism.

PURPOSE: To report visual outcomes following surgical correction of myopic astigmatism with Visian Toric implantable collamer lens (ICL) (STAAR Surgical, Monrovia, CA, USA) at a single tertiary refractive center in the United States. PATIENTS AND METHODS: Toric ICL was implanted in 96 eyes (55 patients) with mean preoperative sphere of -8.98 ± 3.04 diopters (D) and cylinder of -2.67 ± 1.02 D from December 2018 to February 2021. Primary visual outcomes of efficacy, safety, stability, predictability of refractive correction, and astigmatic analysis were reported at three and twelve months postoperatively. Secondary subjective outcomes included patient-reported dry eye symptoms and glare/halos at postoperative visits. Other secondary outcomes were biometric data and postoperative vault over time. RESULTS: At three and twelve months, 75 and 46 eyes were evaluated, respectively. At twelve months, the mean manifest refraction spherical equivalent (MRSE) was -0.23 ± 0.47 D with 93% achieving within ±1.00 D of target refraction. The manifest refractive cylinder (MRC) at twelve months was -0.73 ± 0.51 D, with 86% within ±1.00 D of target. Uncorrected distance visual acuity (UDVA) was 20/20 or better in 74% of eyes at twelve months. No patients lost ≥2 lines of corrected distance visual acuity (CDVA) at twelve months. The mean angle of error was -0.9 ± 10.2° at three months and -1.6 ± 12.8° at twelve months. One patient required bilateral lens rotation, four patients underwent secondary enhancement with LASIK/PRK, and seven patients underwent postoperative limbal relaxing incisions. CONCLUSION: This initial single-site experience finds Toric ICL implantation for myopic astigmatism to be safe and effective. Patients can achieve markedly improved UDVA in a single surgery with stable vision over time and minimal adverse subjective symptoms.

One-year follow-up of a new posterior chamber toric phakic intraocular lens implantation for moderate-to-high myopic astigmatism.

PURPOSE: To investigate refractive and visual outcomes as well as rotational stability following implantation of Eyecryl phakic toric intraocular lens (pIOL) for moderate-to-high myopic astigmatism. METHODS: The efficacy, safety, predictability, stability, and adverse events of Eyecryl toric pIOL were evaluated in patients with spherical refraction from - 4.50 to - 18.50 diopters (D) and cylindrical refraction from - 0.50 to - 5.50 D. RESULTS: This study included 60 eyes of 31 patients. The mean manifest refraction spherical equivalent (MRSE) dropped from - 10.45 ± 2.74 D preoperatively to - 0.34 ± 0.51 D and - 0.40 ± 0.56 D at 6 and 12 months postoperatively, respectively. There was an 81% decrease in astigmatism after surgery. The safety and efficacy of indices were 1.36 ± 0.43 and 1.20 ± 0 .32. At the final follow-up, the rate of eyes within ± 1.00 D and ± 0.50 D of the desired MRSE were 85% and 68.33%, respectively. Vision-threatening complications were not observed during the follow-up. CONCLUSIONS: The implantation of pIOL was effective, safe, and predictable in patients with moderate-to-high myopic astigmatism during 1-year follow-up.

Comparative evaluation of rotational stability of toric IOLs with four-eyelet vs two-eyelet capsular tension rings in eyes with high myopia.

AIM: To compare the rotational stability of Toric intraocular lens (IOLs) implantation combined with four-eyelet or two-eyelet capsular tension rings (CTRs) in eyes with high myopia and cataract. METHODS: This prospective randomized controlled interventional study included 33 eyes which had preoperative corneal astigmatism ≥1.5 D and ocular axial length ≥25.5 mm. These eyes were randomly divided into two groups to undergo phacoemulsification and toric IOL implantation with either four-eyelet CTR implantation (group A, n=16) or two-eyelet CTR implantation (group B, n=17). Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), phoropter examination results, and toric IOL rotation degrees were tested 6mo after the surgery. RESULTS: In both groups, the toric IOL was in the capsular sac 6mo after surgery. The difference between the two groups in terms of visual outcome was not found to be statistically significant (P>0.05) at a follow-up of 6mo. The mean residual astigmatism values were 0.56±0.22 D and 0.92±0.24 D in A and B groups, respectively (P<0.001). The mean rotation degree of IOL was 1.00°±0.73° in group A and 3.53°±1.46° in group B (P<0.001). CONCLUSION: In cataract patients with high myopia and astigmatism, four-eyelet CTR can effectively increase the rotation stability of toric IOLs, achieving the desired goal of correcting corneal astigmatism.

Influence of Ocular Residual Astigmatism and Target-Induced Astigmatism on the Efficacy of the Implantation of a Toric Implantable Collamer Lens With Central Hole for Myopic Astigmatism Correction.

PURPOSE: To investigate the effects of ocular residual astigmatism (ORA) and target-induced astigmatism (TIA) on the efficacy of toric implantable collamer lens (TICL) with central hole for myopic astigmatism correction. METHODS: Retrospective case series. One hundred and eighteen eyes implanted with a TICL (V4c) from 118 patients were included. Subjective refraction and corneal topography were examined preoperatively, at 1 and 12 months postoperatively. The eyes were divided into the low-ORA ( ≤ 0.5 D) and high-ORA (>0.5 D) groups based on vector analysis, and into the low-TIA (≥0.75D and <2 D) and the high-TIA (≥2 D and ≤ 4 D) groups according to preoperative refractive astigmatism. Correction index (CI) and index of success (IOS) were compared between different groups. RESULTS: All surgeries were uneventful, and no complications occurred during follow-up. At 1 and 12 months postoperatively, no significant differences were found in CI or IOS values between the high and low ORA groups, while significantly higher CI and lower IOS were detected in the high-TIA group than in the low-TIA group (P < 0.05). No significant difference was found in CI between 1 and 12 months postoperatively in either group (P > 0.05). However, significantly lower IOS was found at 12 months compared with 1 month postoperatively for each group (P < 0.05). CONCLUSIONS: Toric implantable collamer lens (TICL) implantation is effective in correcting myopic astigmatism and is more effective in eyes with high TIA, while ORA has a minor effect.

Visual Outcomes After Sequential Posterior Chamber Phakic IOL with Corneal Refractive Surgery (Bioptics) for the Treatment of Myopic Astigmatism.

PURPOSE: To report the outcomes of sequential posterior chamber phakic intraocular lens (PC-pIOL) with corneal refractive surgery in conventional (PC-pIOL prior to refractive surgery) and reverse (refractive surgery prior to PC-pIOL) bioptics for treating high myopic astigmatism. SETTING: Tertiary refractive center, Draper, Utah, USA. DESIGN: Retrospective case series. METHODS: Medical records of patients who underwent planned bioptics were reviewed. Surgery involved PC-pIOL placement using an implantable collamer lens (ICL) with preceding or subsequent LASIK or PRK. Pre- and postoperative manifest spherical equivalent (SEQ), visual acuity, and PC-pIOL vault were analyzed. RESULTS: Of the 51 eyes present at 12 months postoperatively, 49 eyes (96%) achieved target SEQ within ±1.00 D and an identical amount achieved refractive astigmatism ≤1.00 D. Post-bioptics eyes achieved a postoperative UDVA equal to or better than preoperative CDVA in 45 eyes (88%). Efficacy and safety indices were 1.08 ± 0.20 (41 eyes) and 1.13 ± 0.22 (44 eyes) for conventional bioptics and 0.99 ± 0.42 (7 eyes) and 1.15 ± 0.38 (7 eyes) for reverse bioptics eyes at 12 months. The maximum PC-pIOL vault of conventional bioptics eyes (27 eyes) within 6 months before and after LASIK/PRK was 385 ± 159 µm and 377 ± 135 µm, respectively (P = 0.71). CONCLUSION: Bioptics for high myopic astigmatism was safe and effective. Reverse bioptics, although not as traditional, could provide similar results. Additionally, the PC-pIOL vault does not appear to be affected by LASIK/PRK.