Comparison of visual quality after EVO-ICL implantation and SMILE to select the appropriate surgical method for high myopia

Changes of dysfunctional lens index before and after implantable collamer lens V4c implantation in patients with moderate-to-high myopia

BACKGROUND

Dysfunctional lens index (DLI) changing is rarely reported after implantable collamer lens (ICL) implantation. In the current research, we hope to investigate the changes of DLI by ray-tracing aberrometry before and after implantation of the posterior chamber phakic implantable collamer lens with a central artificial hole for patients with moderate-to-high myopia.

METHODS

This retrospective, observational case series included 206 eyes of 104 patients with moderate-to-high myopia who underwent ICL V4c implantation. Data were collected on ocular indicators preoperatively and at 1 day, 1, 3, and 6 months postoperatively. The i-Trace Visual Functional Analyzer was used to assess the DLI measurement.

RESULTS

The overall values of safety index and efficacy index were both more than 1. Preoperatively, the mean spherical equivalent (SE) of included 206 eyes was - 10.77 ± 3.46 diopter (D). Then at 1-day postoperation, the mean SE was - 0.22 ± 0.55 D, and barely changed from 1 day to 6 months postoperatively. Although the endothelial parameters had no significant differences between preoperation and postoperation, the mean loss of endothelial cells was 0.74 ± 0.98% at 6 months. Regarding the vault, there was a significant difference between each time of follow-up (P < 0.001). The mean of the vault decreased 109.6 ± 13.5 µm from 1-day post-op to 6 months post-op. The DLI values were 3.70, 9.26, 10.00, and 9.68 at baseline, 1, 3, and 6 months, respectively (P < 0.001), but no significant differences were found between 1, 3, and 6 months postoperatively (P > 0.05). The preoperative lnDLI showed a significant positive linear correlation (r = 0.621, P < 0.001) with the preoperative spherical equivalent (SE). The lnDLI was negatively correlated with the axial length (r = - 0.462, P < 0.001), corneal thickness (r = - 0.207, P = 0.003), preoperative LogMAR UDVA (r = - 0.189, P = 0.006), and preoperative LogMAR CDVA (r = - 0.306, P < 0.001).

CONCLUSIONS

The postoperative refractive parameters were confirmed excellent in efficacy, predictability, and stability in half a year. The DLI was significantly improved after the ICL V4c implantation in patients with moderate-to-high myopia and showed good stability during the follow-up periods. The DLI deserves a more comprehensive understanding and application in clinical services.

Intensive topical steroid regimen for enhanced very early recovery after small incision lenticule extraction

OBJECTIVE

This study aims to investigate the topical steroid regimen after small incision lenticule extraction (SMILE) for its effect on very early restoration of visual quality.

METHODS

A total of 180 patients (360 eyes) who underwent SMILE were enrolled. These patients were randomly assigned to three groups, with 60 patients in each group. The only difference among these three groups was the administration of 0.1% fluorometholone (FML) eye drops within two hours after SMILE: no FML in group A, 0.1% FML once every hour in group B and 0.1% FML once every half hour in group C. The corrected distance visual acuity (CDVA), objective scattering index (OSI), modulation transfer function (MTF) cut-off, Strehl ratio (SR) and incidence of subjective symptoms were evaluated preoperatively, at 2, 4 and 24 h and one week after SMILE.

RESULTS

The CDVA, MTF cut-off and SR values were significantly higher in group C, when compared to the other two groups, at 2 and 4 h after SMILE (p < 0.05). Furthermore, the OSI and incidence of subjective symptoms were significantly lower in group C, when compared to the other two groups, at 2 and 4 h after SMILE (p < 0.05). However, no significant differences in CDVA, MTF cut-off, SR, OSI and the incidence of subjective symptoms were detected among the three groups at 24 h and one week after SMILE (p > 0.05).

CONCLUSION

The administration of 0.1% FML eye drops every half hour within two hours after SMILE accelerates the restoration of visual and optical quality, and reduces the incidence of subjective symptoms during the very early phase after surgery.

Four-year visual outcomes and optical quality of SMILE and implantable collamer lens V4c (EVO-ICL) implantation for high myopia: a retrospective study

BACKGROUND

To compare the 4-year visual outcomes of implantable collamer lens V4c (EVO-ICL) implantation and small incision lenticule extraction (SMILE) for high myopia and astigmatism.

METHODS

This retrospective case study included 64 eyes of 40 patients. These patients with preoperative manifest refraction spherical equivalent (SE) between - 6.00 and - 10.00 diopters (D) were screened from the database of SMILE and EVO-ICL implantation procedures in 2015. The ICL group [32 eyes of 19 patients (mean age, 29.6 ± 6.3 years); mean SE, -8.71 ± 1.06 D] and SMILE group [32 eyes of 21 patients (mean age, 27.7 ± 5.6 years); mean SE, -8.35 ± 0.65D] were compared. All patients were then prospectively examined at a four-year follow-up for routine postoperative examinations, higher-order ocular aberrations, retinal image quality and a questionnaire.

RESULTS

The safety indexes were 1.15 ± 0.14 and 1.22 ± 0.21 (P = 0.36) for the SMILE and ICL groups, respectively. No eyes lost two or more lines of CDVA in either group. The efficacy indexes were 0.97 ± 0.16 and 0.96 ± 0.19 (P = 0.87), respectively. Twenty-three eyes (72%) in ICL and 26 eyes (81%) in SMILE groups were within ± 0.5 D of the attempted SE (P < 0.01). ICL-treated eyes had significantly less spherical aberration and coma (P < 0.01 and < 0.05, respectively) postoperatively. Halos were the prevalent visual disturbance in both groups.

CONCLUSION

SMILE and EVO-ICL implantation provided safe and effective correction of high myopia. SMILE showed slightly better long-term predictability. Mild postoperative visual disturbances were observed after ICL and SMILE at 4-year follow-up.

Quality of vision after myopic refractive surgeries: SMILE, FS-LASIK, and ICL

BACKGROUND

To characterize the quality of vision after SMILE, FS-LASIK, and ICL implantation and evaluate the related factors.

METHODS

131 eyes of 131 myopic patients (90 female, 41 male) who underwent refractive surgeries including SMILE (35 patients), FS-LASIK (73 patients), and ICL implantation (23 patients) were analyzed. The Quality of Vision questionnaires were completed 3 months after surgery, and the results were characterized and analyzed with baseline characteristics, treatment parameters, and postoperative refractive outcomes using logistic regression analysis to find out predicted factors.

RESULTS

Mean age was 26.5 ± 4.6 years (range: 18 to 39 years) and mean preoperative spherical equivalent was - 4.95 ± 2.04 diopters (D) (range: -1.5 to -13.5). Safety and efficacy index was comparable between different techniques: the safety index was 1.21 ± 0.18, 1.22 ± 0.18, and 1.22 ± 0.16 and the efficacy index were 1.18 ± 0.20, 1.15 ± 0.17, 1.17 ± 0.15 for SMILE, FS-LASIK and ICL respectively. The mean overall QoV score was 13.40 ± 9.11, with mean frequency, severity, and bothersome score of 5.40 ± 3.29, 4.53 ± 3.04, and 3.48 ± 3.18 respectively, and there was no significant difference between different techniques. Overall, the symptom with the highest scores was glare, following fluctuation in vision and halos. Only the scores of halos were significantly different among different techniques (P < 0.000). Using ordinal regression analysis, mesopic pupil size was identified as a risk factor (OR = 1.63, P = 0.037), while postoperative UDVA was a protective factor (OR = 0.036, P = 0.037) for overall QoV scores. Using binary logistic regression analysis, we found that patients with larger mesopic pupil size had an increased risk to experience glare postoperatively; compared to ICL, patients who underwent SMILE or FS-LASIK tended to report fewer halos; patients with better postoperative UDVA were less likely to report blurred vision and focusing difficulty; with larger residual myopic sphere postoperatively, patients experienced focusing difficulties and difficulty judging distance or depth perception more frequently.

CONCLUSIONS

SMILE, FS-LASIK, and ICL had comparable visual outcomes. Overall, glare, fluctuation in vision, and halos were the most frequently experienced visual symptoms 3 months postoperatively. Patients with ICL implanted tended to report halos more frequently compared with SMILE and FS-LASIK. Mesopic pupil size, postoperative UDVA, and postoperative residual myopic sphere were predicted factors for reported visual symptoms.

A meta-analysis of visual outcomes and optical quality after small incision lenticule extraction versus implantable collamer lens for myopia

OBJECTIVE

To evaluate possible differences in visual outcome and optical quality when small incision lenticule extraction (SMILE) versus implantable collamer lens (ICL) is used to correct myopia.

METHODS

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials were searched up to August 2021 to identify relevant studies. The PRISMA guidelines were followed. Primary outcomes were postoperative efficacy, safety, and predictability at the end of follow-up. Secondary outcomes were changes in modulation transfer function cutoff frequency (MTF _cut-off), objective scatter index (OSI) values, total higher-order aberrations (HOAs), spherical aberrations, and coma aberrations.

RESULTS

Seven studies with a total of 1296 eyes (SMILE: 731 eyes; TECXL: 565 eyes) were included. The ICL group had a better MTF _cut-off (P = 0.007) and less change in the proportion of HOAs (P < 0.001), spherical aberrations (P = 0.009), and coma (P = 0.006) than the SMILE group. For the other outcomes, there were no statistically significant differences.

CONCLUSIONS

SMILE and ICL implantation are comparable in efficacy, safety, and predictability for correcting myopia. Larger studies with longer follow-up times are warranted to provide a better understanding of the benefits of SMILE and ICL implantation.

Postoperative efficacy, safety, predictability, and visual quality of implantable collamer lens implantation versus small incision lenticule extraction in myopic eyes: a Meta-analysis

AIM

To compare the postoperative efficacy, safety, predictability, and visual quality of implantable collamer lens (ICL) implantation versus small incision lenticule extraction (SMILE) in myopia eyes.

METHODS

PubMed, EMBASE, Web of Science, Cochrane Library and several Chinese databases were searched at May 2021 to select relevant studies in comparison of clinical outcomes between ICL implantation and SMILE for myopia. The primary outcomes were efficacy, safety, and predictability. And the secondary outcomes were postoperative higher-order ocular aberrations (HOAs), modulation transfer function cutoff frequency (MTF), objective scatter index (OSI), contrast sensitivity and a quality of vision (QoV) questionnaire.

RESULTS

A total of 1036 eyes from 10 studies, of which 503 eyes underwent ICL implantation and 533 eyes underwent SMILE, were enrolled in this Meta-analysis. Pooled results revealed that ICL group had a better safety index and post-corrected distance visual acuity (CDVA) (P=0.007, <0.00001, respectively), and a lower percentage of eyes with a postoperative CDVA lost 1 line (P=0.007) than the SMILE group. No significant differences were found in comparison of the other primary outcomes. In the long-term follow-up (>6mo), ICL group had a lower total HOA, coma, and spherical aberration than SMILE group (P=0.003, <0.00001, 0.04). Yet higher trefoil was found in ICL group at 6mo after surgery (P=0.003). Additionally, ICL group also had a higher MTF value (P=0.02), and a higher contrast sensitivity score for spatial frequencies of 1.5, 6, and 12 cpds (P=0.02, 0.005, 0.02, respectively). And it also had a lower score of bothersome in QoV questionnaire than SMILE group (P=0.003).

CONCLUSION

ICL implantation and SMILE have similar and comparable outcomes in term of the efficacy and predictability for correcting high myopia. However, ICL group is relatively safer and also has better visual quality in comparison of SMILE group.

Comparison of Visual Outcomes and Optical Quality of Femtosecond Laser-Assisted SMILE and Visian Implantable Collamer Lens (ICL V4c) Implantation for Moderate to High Myopia: A Meta-analysis

PURPOSE

To compare visual outcomes and optical quality of femtosecond laser-assisted small incision lenticule extraction (SMILE) and Visian Implantable Collamer Lens (ICL V4c; STAAR Surgical) implantation for moderate to high myopia.

METHODS

For this systematic review and meta-analysis, the Cochrane, PubMed, Embase, and Chinese databases (Wan-fang data and CNKI) were comprehensively searched to identify studies comparing SMILE and ICL V4c implantation. Data of interest were extracted and analyzed by Stata V.16.0 software (StataCorp). The weighted mean differences and their 95% confidence intervals were used to assess the strength of the association.

RESULTS

Twelve studies incorporating 1,390 eyes of 822 patients were included. The analysis revealed ICL V4c implantation had a significantly higher safety index and lower high order aberrations, coma, and spherical aberration than SMILE in treating moderate to high myopia (P < .05). Subgroup analysis revealed such differences were more prominent in patients with high myopia who had shorter follow-up duration. When follow-up was longer than 6 months, the differences in safety index and total HOAs became nonsignificant (P > .05). The two procedures had no difference in efficacy index, postoperative visual acuity, spherical equivalent, trefoil, Objective Scatter Index, or modulation transfer function cut-off frequency (P > .05).

CONCLUSIONS

Both SMILE and ICL V4c implantation were safe and efficient for moderate to high myopia. Compared with SMILE, ICL V4c implantation might provide better postoperative visual quality in patients with high myopia in the early postoperative period. [J Refract Surg. 2022;38(6):332-338.].

A Comprehensive Investigation of Contrast Sensitivity and Disk Halo in High Myopia Treated With SMILE and EVO Implantable Collamer Lens Implantation

Purpose

To investigate the clinical outcomes in small incision lenticule extraction (SMILE) and EVO implantable Collamer lens (ICL)–treated high myopia.

Methods

Thirty-three SMILE-treated and 32 EVO ICL-treated patients were included and followed up for 6 months. Subjective refraction, contrast sensitivity, and disk halo size were measured preoperatively and postoperatively. Patient-reported outcomes (PROs) were obtained at the final visit.

Results

Significant differences in efficacy and safety indices were observed between the SMILE and EVO ICL groups at 6 months postoperatively (P < 0.05). In the SMILE group, the mesopic contrast sensitivity at 2.2 cycles per degree (cpd) and photopic contrast sensitivity at 0.5, 3.4, and 7.1 cpd were significantly improved. In the EVO ICL group, the mesopic contrast sensitivity at 7.1 cpd and photopic contrast sensitivity at 0.5, 7.1, and 14.6 cpd were significantly improved. The halo radii after SMILE were significantly increased at 1 week, showed a decreasing trend at 1 month, returned to baseline at 3 months, and progressed stably at 6 months. However, it was unchanged in the EVO ICL group. Regarding subjective experience, haloes were the most common disturbance with mild and little bothersomeness after EVO ICL in contrast to starbursts after SMILE.

Conclusions

EVO ICL implantation yielded better visual outcomes, improved contrast sensitivity particularly at high spatial frequencies, had a stabler disk halo size, and increased incidence of haloes, with less influence than that of SMILE.

Translational Relevance

The disk halo and PRO findings will be of benefit for consultations and evaluations in visual performance and disturbances.

Implantable collamer lens versus small incision lenticule extraction for high myopia correction: A systematic review and meta-analysis

Purpose

To compare the efficacy, safety, predictability and visual quality between implantable collamer lens (ICL) implantation and small incision lenticule extraction (SMILE) for high myopia correction in adults.

Methods

A systematic review and meta-analysis was conducted. A comprehensive literature search was done based on databases including PubMed, Science Direct, Embase, and the Cochrane Central Register of Controlled Trials. The efficacy index, safety index, changes in Snellen lines of corrected distance visual acuity (CDVA), predictability (difference between post-operative and attempted spherical equivalent error, SER), incidence of halos, and change in higher-order aberrations (HOAs) were compared. Mean difference (MD) and 95% confidence interval (CI) was used to estimate continuous outcomes, risk ratio (RR) and 95%CI was used to estimate categorical outcomes.

Results

Five observational studies involving 555 eyes were included in this review. Studies’ sample sizes (eyes) ranged from 76 to 197. Subjects’ refraction ranged from -6 diopter (D) to -12D. Study duration of most researches were 6 months or 12 months. Compared to SMILE, ICL implantation showed better efficacy index (MD=0.09, 95%CI:0.01 to 0.16) and better safety index (MD=0.08, 95%CI: 0.00 to 0.16). Compared with SMILE, more ICL-treated eyes gained one or more Snellen lines of CDVA (RR=1.54, 95%CI:1.28 to 1.86), more gained two or more lines (RR=2.09, 95%CI:1.40 to 3.13), less lost one or more lines (RR=0.17, 95%CI:0.05 to 0.63). There was no difference in predictability between two treatments, RRs of predictability of within ±0.5D and ±1D were 1.13 (95%CI: 0.94 to 1.36) and 1.00 (95%CI: 0.98 to 1.02). Compared with SMILE, ICL implantation came with a higher risk of halos [RR=1.79, 95%CI: 1.48 to 2.16] and less increase in total HOAs (MD=-0.23, 95%CI: -0.42 to -0.03).

Conclusion

Compared with SMILE, ICL implantation showed a higher risk of halos, but equal performance on SER control, and better performance on efficacy index, safety index, CDVA improvement and HOAs control. Overall, ICL implantation might be a better choice for high myopia correction in adults.

Pure ICL Implantation: A Novel Ophthalmic Viscosurgical Device-Free Method

PURPOSE

To assess the clinical efficiency of a novel ophthalmic viscosurgical device-free (OVD-free) method for intraocular collamer lens (EVO-ICL) implantation in myopic eyes.

METHODS

In this study, 40 patients underwent ICL implantation for both eyes: one eye underwent traditional ICL implantation, and the other eye underwent OVD-free (pure) ICL implantation. Preoperative and postoperative UDVA, BCVA, equivalent spherical degree (SE), IOP, visual quality index, subjective visual quality scale, corneal endothelial cell density (ECD), operation time, and complications were compared between and within the traditional and pure ICL implantation groups.

RESULTS

Increased IOP >22 mmHg 2 h after surgery was noted in 8 eyes (20%) in the traditional group, but not in the pure group (0%, P < 0.001). Increased IOP relative to baseline was significantly higher at 2 h after surgery for the traditional group compared with the pure group (P < 0.001). UDVA, BCVA, and SE were significantly improved in the pure group compared with those in the traditional group 1 day (P < 0.001, P=0.003) after implantation, but not 1 week or 3 months after. Modulation transfer function cut-off frequency (MTF cut-off), Strehl ratio (SR), and OV20% were significantly better in the pure group than in the traditional group 1 day after implantation (P=0.013, P=0.009, and P=0.004). No significant difference in ECD changes within or between groups was observed (P > 0.05). The operation time for the pure group (2.897 ± 0.346 min) was significantly shorter than that for the traditional group (4.444 ± 0.656 min; P < 0.001). No complications were reported for either group during the observation period, except early IOP elevation in the traditional group.

CONCLUSIONS

The pure ICL implantation method was associated with faster visual acuity recovery, shorter operation time, and more stable intraocular pressure. Pure ICL represents a safe and convenient method for ICL implantation compared with the traditional method, completely eliminating OVD-related complications without causing additional complications.

Comparison of the optical quality after SMILE and FS-LASIK for high myopia by OQAS and iTrace analyzer: a one-year retrospective study

BACKGROUND

To compare the correction effect and optical quality after small-incision lenticule extraction (SMILE) and femtosecond laser assisted laser in situ keratomileusis (FS-LASIK) for high myopia.

METHODS

51 high myopia eyes after SMILE and 49 high myopia eyes after FS-LASIK were enrolled and divided into two groups retrospectively. The OQAS and iTrace analyzer were used for optical quality inspection. Between the two groups the spherical equivalent (SE), astigmatism, uncorrected distant visual acuity (UDVA), strehl ratio (SR), modulation transfer function cutoff frequency (MTF cutoff), objective scatter index (OSI) and wavefront aberrations were analyzed and compared before surgery and at 1, 6 and 12 months after surgery.

RESULTS

After the operation: (1) SE and astigmatism declined and UDVA increased significantly in both groups, and UDVA was better after SMILE than FS-LASIK. (2) SR and MTF cutoff reduced and OSI increased significantly after SMILE and FS-LASIK. SR and MTF cutoff were significantly higher after SMILE than FS-LASIK. OSI was significantly lower after SMILE than FS-LASIK. (3) The total wavefront aberration, total low-order wavefront aberration, defocus and astigmatism aberration as well as trefoil aberration reduced significantly in both groups. The total high-order wavefront aberration increased significantly after FS-LASIK. The spherical and coma aberration increased significantly in both groups. The total high-order wavefront aberration and coma aberration at 1 month were higher after FS-LASIK than SMILE.

CONCLUSION

The optical quality descended after SMILE and FS-LASIK. SMILE was superior to FS-LASIK at the correction effect and optical quality for high myopia. The combination of OQAS and iTrace analyzer is a valuable complementary measurement in evaluating the optical quality after the refractive surgery.

TRIAL REGISTRATION

This is a retrospective study. This research was approved by the ethics committee of Xiangya Hospital and the IRB approval number is 201612074.

Comparison of the visual performance of iris-fixated phakic lens and implantable collamer lens to correct high myopia

Background

To compare visual performance between the iris-fixated phakic intraocular len (pIOL) and implantable collamer len (ICL) to correct high myopia.

Methods

Twenty-four eyes underwent iris-fixated pIOL implantation and 24 eyes underwent ICL implantation. At the 6-month follow-up, the best-corrected visual acuity (BCVA) and uncorrected distance visual acuity (UDVA) were compared between the iris-fixated pIOL and ICL groups. The objective scatter index (OSI), modulation transfer function (MTF) cutoff, and ocular aberrations were performed to evaluate postoperative visual quality between the two groups.

Results

No significant difference was found in UDVA, BCVA, and spherical equivalent between the iris-fixated pIOL and ICL groups (P > 0.05). Six months after surgery, the following values were significantly higher in the ICL group than in the iris-fixated pIOL group: MTF cutoff, strehl ratio and optical quality analysis system values at contrasts of 9 %, 20 %, and 100 % (P < 0.01). The OSI in the iris-fixated pIOL group was higher than in the ICL group 6 months after surgery (P < 0.01). All high-order aberrations were slightly more severe in the iris-fixated pIOL group than in the ICL group 6 months after surgery, although only trefoil (P = 0.023) differed significantly in this regard.

Conclusions

Both iris-fixated lenses and ICLs can provide good visual acuity. ICLs confer better visual performance in MTF-associated parameters and induce less intraocular light scattering than iris-fixated pIOLs.

Posterior-chamber phakic implantable collamer lenses with a central port: a review

We aimed to summarize the outcomes reported following the implantation of the V4c implantable collamer lens with a central port (ICL, STAAR Surgical Inc) for myopia correction. A literature search in PubMed, Web of Science and Scopus was carried out to identify publications reporting clinical outcomes of patients who were implanted with the V4c ICL model and had a follow‐up period of at least 6 months. A total of 35 clinical studies published between 2012 and 2020 were included in the present review. A comprehensive analysis of the available data was performed, focusing on visual and refractive outcomes at different time‐points post‐surgery. In addition, adverse events and other parameters such as endothelial cell density, intraocular pressure and vault measurements—which were evaluated in some of the studies—were also compared. This review encompassed a total of 2904 eyes. The outcomes reported in this review lead us to conclude that ICL V4c implantation for myopia correction is a safe and efficient procedure, with stable visual and refractive outcomes and low adverse event rates. The patient’s anterior segment should be thoroughly characterized, and the ICL parameters should be carefully selected so as to achieve good outcomes and avoid complications.

Visual outcomes after small incision lenticule extraction and implantable collamer lens V4c for moderate myopia: 1-year results

PURPOSE

To compare 1-year visual outcomes after implantable collamer lens V4c (EVO-ICL) implantation and small incision lenticule extraction (SMILE) for moderate myopia.

METHODS

In this retrospective study, 67 eyes of 39 patients with a preoperative manifest refraction spherical equivalent between - 3.00 and - 6.00 diopters (D) were selected from a database of SMILE and ICL implantation procedures performed from April 2018 to December 2018. Thirty-two eyes of 20 patients underwent EVO-ICL implantation, and 35 eyes of 19 patients underwent SMILE. At the routine 1-year follow-up appointment, all selected patients were examined for higher-order ocular aberrations, retinal image quality, and a quality of vision (QoV) questionnaire. This data was then analyzed.

RESULTS

No complications were observed. Uncorrected and corrected visual acuities at 1 year after surgery were - 0.13 ± 0.07 and - 0.15 ± 0.06 logMAR in the SMILE group, and - 0.10 ± 0.07 and - 0.16 ± 0.05 logMAR in the ICL group. Twenty-nine eyes (90.6%) which underwent ICL implantation and 34 eyes (97.1%) which underwent SMILE were within ± 0.5 D of the attempted spherical equivalent (P = 0.49). Changes in coma after ICL were significantly less than after SMILE (P = 0.002). The leading complaints after ICL and SMILE were halos (84.4%) and blurred vision (65.7%), respectively.

CONCLUSIONS

Both SMILE and ICL implantation provided good safety, efficacy, and predictability in correcting moderate myopia. The subjective visual complaints consisted mainly of halos after ICL and starbursts and blurred vision after SMILE.

Comparison of objective and subjective visual quality early after implantable collamer lens V4c (ICL V4c) and small incision lenticule extraction (SMILE) for high myopia correction

PURPOSE

To investigate differences in the objective and subjective visual quality of patients with high myopia following implantable collamer lens V4c (ICL V4c) versus small incision lenticule extraction (SMILE) early postoperatively.

METHODS

This prospective analysis included 94 eyes of 57 patients (8 males) in the ICL V4c group (mean spherical equivalent (SE), -8.07 ± 1.03 dioptres (D)) and 103 eyes of 57 patients (13 males) in the SMILE group (mean SE, -7.85 ± 0.78 D). Refractive parameters and wavefront aberrations were recorded preoperatively and 6 months postoperatively. Subjective visual quality was scored with the Quality of Vision questionnaire, and operation satisfaction was evaluated 6 months postoperatively.

RESULTS

At 6 months postoperatively, the efficacy index was 1.17 ± 0.16 in the ICL and 1.09 ± 0.20 in the SMILE group; the safety index was 1.21 ± 0.18 in the ICL and 1.12 ± 0.16 in the SMILE group. A significant increase in total higher-order aberrations (HOAs) in both the ICL and SMILE groups was observed, but to a lesser degree in ICL (p < 0.05). In the ICL group, trefoil significantly increased (p < 0.05), whereas in the SMILE group, coma, trefoil and spherical aberration significantly increased (p < 0.05). Glare, haloes and blurred vision had the highest incidences after both types of surgery, and postoperative haloes were significantly more common following ICL; 96.1% of ICL-treated and 94.9% of SMILE-treated patients were satisfied with their visual outcomes.

CONCLUSION

ICL V4c caused lower HOAs induction than SMILE. Despite the postoperative visual disturbances, both ICL and SMILE provided good efficacy, safety, predictability and high satisfaction in correcting high myopia.

Agreement between subjective and predicted high and low contrast visual acuities with a double-pass system

PURPOSE

To evaluate the agreement between subjective high and low contrast visual acuity (VA) and predicted values from double-pass system measurements in healthy candidates to laser refractive surgery.

METHODS

Ninety-two eyes measured during the preoperative screening to laser refractive surgery were included in this retrospective analysis. High contrast subjective visual acuity (HCVA) and low contrasts at 20% (LCVA20) and 9% (LCVA9) were compared with the predicted VA obtained with a commercial double-pass system (OQAS) at the same levels of contrast, 100% (OV100), 20% (OV20), and 9% (OV9). The agreement was evaluated with Bland-Altman analysis computing the limits of agreement (LoAs) and the correlations with the spearman rho.

RESULTS

An underestimation of VA was obtained with the double-pass system for the highest contrast. Differences between predictive and subjective measurements were statistically significant for 100% contrast (- 0.08 logMAR, p < 0.0005), but not for 20% (- 0.03 logMAR, p = 0.07) and 9% (- 0.02 logMAR, p = 0.9) of contrasts. The LoAs increased with the decrease of contrast from 0.29 with 100% to 0.39 logMAR with 9% of contrast. A weak correlation was obtained between subjective and predicted VA (rho ≤ 0.33) that was only significant for 100% (p = 0.001) and 20% (p = 0.004) contrasts.

CONCLUSION

Mean differences between methods were reasonably small so mean results obtained for predicted VA in OQAS studies can be considered as reliable, at least in healthy subjects and for low contrast. However, limits of agreement were considerably poor which means that OQAS cannot replace individual subjective measurements of VA in clinical practice.

Short-time evaluation on intraocular scattering after implantable collamer lens implantation for correcting high myopia

Background

To compare the intraocular scattering before and after implantation of implantable collamer lens (ICL) V4c for correction of high myopia in a short term.

Methods

In this study, 38 eyes of 19 patients who underwent the implantation of ICL V4c were followed up for 3 months. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), objective scattering index (OSI), modulation transfer function cutoff frequency (MTF cutoff), strehl ratio (S/R), OV100%, OV20% and OV9% were measured pre- and postoperatively. Meantime, the Pseudophakic Dysphotopsia Questionnaire (PDQ) was scored to evaluate the subjective satisfaction of intraocular scattering pre- and postoperatively.

Results

The UCVA were − 0.02 ± 0.06, − 0.03 ± 0.07 and − 0.04 ± 0.07 logMAR at 1 week, 1 month and 3 months postoperatively which were significantly better than those preoperatively (P < 0.05). The BCVA were − 0.09 ± 0.09, − 0.09 ± 0.1 and − 0.1 ± 0.11 logMAR at 1 week, 1 month and 3 months after surgery, which were better than those before surgery significantly (t = 15.64, P < 0.05). The mean OSI were 2.37 ± 1.6, 1.63 ± 0.94, 1.5 ± 0.86 and 1.43 ± 1.05 preoperatively, 1 week, 1 month and 3 months postoperatively which was found significant difference (F = 12.92 P < 0.05). No significant differences were found in MTF cut off (F = 0.61, P = 0.62), S/R (F = 0.58, P = 0.36), OV100% (F = 0.966, P = 0.65), OV20% (F = 0.121, P = 0.96) and OV9% (F = 1.01, P = 0.30) between pre- and postoperatively. The PDQ results indicated that intraocular scattering reduced at 3 months after surgery significantly (P < 0.05).

Conclusions

The ICL V4c implantation for correcting high myopia induced less intraocular scattering and visual disorder than spectacle correction.

Evaluation of visual quality after EVO-ICL implantation for hypermyopia: An observational study

The purpose of this retrospective study was to evaluate the visual quality, objective scattering index, aberration, etc after Implantable Collamer Lens with center hole (EVO-ICL) implantation to treat patients with hypermyopia (diopter > -10 D).A total of 30 eyes underwent EVO-ICL implantation. The uncorrected distance visual acuity (UDVA), best-corrected visual acuity (BCVA), equivalent spherical degree, aberration, visual quality parameters, and corneal endothelial cell density were compared preoperative and postoperative. Fill in the National Eye Institute Refractive Error Quality of Life Instrument-42 before and after surgery.The modulation transfer function (MTF), Optical Quality Analysis System (OQAS) II values (OV 100%, 20%, 9%), and Stahl ratio 1 and 3 months after surgery were higher than the respective preoperative values. The objective scatter index value increased 1 week after surgery, but decreased 1 and 3 months after surgery compared with the preoperative values. Total aberration (TA), total low-order aberration (tLOAs), and defocus decreased at 1 week and 3 months after EVO-ICL implantation. Total high-order aberration (tHOAs) and spherical aberration were significantly increased 1 week after surgery and decreased 3 months after surgery, and the difference was statistically significant. Astigmatism, coma, and clover were not significantly different in each time period. TA, tLOAs, tHOAs, defocus, and spherical aberration were higher at 1 week than 3 months after surgery. At 3 months after surgery, the scores of the patients' NEI-RQL-42 scale were all improved except that the glare was lower than that before surgery. There was no significant difference in the density of corneal endothelial cells before and 3 months after surgery.For patients with hypermyopia, the postoperative subjective and objective visual quality of EVO-ICL implantation was better than preoperative.

Optical quality in low astigmatic eyes with or without cylindrical correction

PURPOSE

To investigate whether optical quality could be improved by cylindrical correction for low astigmatic eyes with different amounts and axis orientations in patients with myopia up to - 3.00 diopters (D).

METHODS

A cross-sectional study enrolling healthy young eyes with 0 to - 3.00 D myopia and - 0.50 to - 0.75 D myopic astigmatism was implemented. With a repeated-measures design, outcome measures were sequentially obtained for each subject under two correction modalities: spherocylindrical correction and spherical correction. Subjective refraction was used to determine the refractive prescriptions accordingly in the two correction modalities to obtain optimal subject-reported visual acuity. Primary outcomes were optical quality parameters including objective scatter index (OSI), modulation transfer function (MTF) cut-off, Strehl ratio (SR), and a simulated contrast visual acuity-optical quality analysis system (OQAS) values (OV) obtained by a double-pass system. Corrected distance visual acuity (CDVA) was measured as a secondary outcome. Outcome comparisons between the two correction modalities were performed by grouping in different amounts (- 0.50 D, - 0.75 D) and axes (with the rule, WTR; against the rule, ATR; oblique, OBL) of astigmatism.

RESULTS

A total of 194 eyes of 194 subjects were evaluated. Significantly better CDVA were shown by spherocylindrical correction for all types of astigmatism except for - 0.50 D WTR astigmatism (P = 0.831). For eyes with - 0.50 D WTR astigmatism, better outcome was only shown in OSI with spherocylindrical correction (P = 0.019). For eyes with - 0.50 D ATR and OBL astigmatism, spherocylindrical correction demonstrated better outcomes in all parameters except for SR (P > 0.05). For eyes with - 0.75 D astigmatism, significantly better outcomes in all optical quality parameters were shown with spherocylindrical correction regardless of the axis (P < 0.05).

CONCLUSIONS

Eyes with ATR or OBL myopic astigmatism may benefit in optical quality and visual acuity by combining a cylindrical correction even with a low amount down to - 0.50 D. However, optical quality and visual acuity improvement are limited for WTR astigmatic eyes when the amount of astigmatism is less than - 0.75 D.