New technology update: femtosecond laser in cataract surgery

Comparing the efficacy and safety between femtosecond laser-assisted cataract surgery and conventional phacoemulsification cataract surgery: systematic review and meta-analysis

OBJECTIVE

To investigate the efficacy and safety of femtosecond laser-assisted cataract surgery (FLACS) compared with conventional phacoemulsification cataract surgery (CPCS).

METHODS

Randomized controlled trials (RCTs) were systematically searched in PubMed, Embase, Cochrane Library, ClinicalTrials.gov, CNKI, and Wanfang. Main outcomes were visual acuity, capsulotomy parameters, effective lens position, and complications. Secondary outcomes included refractive outcomes, intraoperative parameters, and corneal parameters.

RESULTS

In total, 41 RCTs involving 9310 eyes were included. There was a statistically significant difference in favour of FLACS over CPCS for uncorrected distance visual acuity at 12 months (mean difference [MD] -0.03; 95% CI -0.05 to -0.01); corrected distance visual acuity at 1 week (MD -0.05; 95% CI -0.07 to -0.02) and 12 months (MD -0.02; 95% CI -0.04 to -0.00); area of capsulotomy at 1 month (MD 4.04 mm2; 95% CI 3.45-4.64) and 6 months (MD 5.02 mm2; 95% CI 3.28-6.77); and intraocular lens centroid-pupil centroid distance at 1 week (MD -0.06 mm; 95% CI -0.08 to -0.05), 1 month (MD -0.07 mm; 95% CI -0.09 to -0.06), and 6 months (MD -0.06 mm; 95% CI -0.07 to -0.04). With regard to surgical complications, FLACS was less than CPCS for the incidence of decentred IOL (odds ratio 0.06; 95% CI 0.01-0.24). However, FLACS did not increase the incidence of other intraoperative or postoperative complications except subconjunctival hemorrhage.

CONCLUSIONS

Both FLACS and CPCS are effective and safe. FLACS achieves better visual outcomes in the early postoperative period and long-term follow-up, accompanied by more accurate capsulotomy and more optimized effective lens position than CPCS. However, no difference of visual outcomes was found after middle-term follow-up.

Comparing the time efficiency of two lasers used in FLACS: real-world observational study

PURPOSE

To evaluate time efficiencies in the laser room for 2 different femtosecond laser systems.

SETTING

1 private practice in Atlanta, Georgia, and 1 private practice in Los Angeles, California.

DESIGN

Prospective, observational, single-masked study.

METHODS

Patients scheduled to receive femtosecond laser-assisted cataract surgery (FLACS) included those who were not pregnant, had no previous eye surgeries, and were not scheduled to undergo additional surgical procedures at the time of treatment; patients who received a standard, monofocal lens without undergoing arcuate incisions were excluded. Patients taking Flomax or any tamsulosin were also excluded from the study. Each comparable step in the LenSx and CATALYS workflow was identified and clearly defined. Time for each step was evaluated and compared using t tests and regression analyses to control for patient and site-specific differences between the 2 groups.

RESULTS

Time data were collected for 89 patients (89 eyes). The overall procedure was 2.86 minutes shorter for the LenSx system when compared with the CATALYS system ( P < .05). Per patient, the LenSx system had significantly shorter time for patient positioning (57.26 vs 122.00 seconds; P < .05), imaging (33.23 vs 42.17 seconds; P < .05), laser treatment (21.57 vs 39.67 seconds; P < .05), and undocking/transition (67.13 vs 185.30 seconds; P < .05) compared with the CATALYS system. Regression analyses yielded similar results, with the LenSx system being over 35% (3.21 minutes; P < .05) shorter overall than the CATALYS system controlling for location, age, sex, lens thickness, cataract grade, fragmentation pattern, and arcuate incisions.

CONCLUSIONS

LenSx procedures were significantly shorter than the CATALYS procedures overall, which can enable ophthalmology practices to increase efficiency.

First-in-Human Safety Study of Femtosecond Laser Image-Guided Trabeculotomy for Glaucoma Treatment: 24-month Outcomes

Purpose

Pilot study to evaluate adverse events and intraocular pressure (IOP)-lowering of a novel, noninvasive glaucoma procedure, femtosecond laser, image-guided, high-precision trabeculotomy (FLIGHT).

Design

Prospective, nonrandomized, single-center, interventional, single-arm clinical trial.

Participants

Eighteen eyes from 12 patients with open-angle glaucoma.

Methods

Eighteen eyes from 12 patients underwent FLIGHT, creating a single channel measuring 500-μm wide by 200-μm high through the trabecular meshwork and into Schlemm's canal. Adverse events, IOP, and other parameters were evaluated out to 24 months.

Main Outcome Measures

Outcomes were the rates and types of adverse events and the rate of postprocedure best-corrected visual acuity loss (≥ 2 lines) compared with baseline. Efficacy outcomes were reduction in mean intraocular pressure (IOP) with respect to baseline and the percentage of eyes with a ≥ 20% reduction in IOP.

Results

Eighteen eyes from 12 patients were enrolled in the study; 11 patients (17 eyes) returned at 24 months. There were no serious adverse events related to the laser treatment. Well-defined channels were clearly visible at 24 months by gonioscopy and anterior segment OCT, with no evidence of closure. At 24 months, the mean IOP was reduced by 34.6% from 22.3 ± 5.5 to 14.5 ± 2.6 mmHg (P < 5e-5), with an average of 2.0 ± 1.2 hypotensive medications compared with 2.2 ± 1.1 at baseline (P = 0.22). Fourteen out of the 17 study eyes (82.3%) achieved a ≥ 20% reduction in IOP at 24 months when compared with baseline.

Conclusion

The FLIGHT system demonstrated a favorable safety profile in this initial pilot study, with no device-related serious adverse events. The channels appeared patent at 24 months, indicating medium-term durability.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references.

Capsulotomy enlargement after femtosecond laser treatment among cataract patients of different age groups: a retrospective case series

PURPOSE

Larger-than-planned capsulotomies can occur, yet their association with age and eye parameters remains poorly understood. This study aimed to assess capsulotomy enlargement after femtosecond laser treatment in cataract surgery and to explore a possible correlation of capsulotomy enlargement with age and eye parameters.

METHODS

This retrospective case series included consecutive patients diagnosed with cataracts between 05/2018 and 11/2019. Among them, patients within the age ranges of <18, 18-49, and ≥50 years were assigned to the childhood cataract (CC), young adult cataract (YAC), and age-related cataract (ARC) groups, respectively. The capsulotomy enlargement ratio (CER), age, degree of cataract, lens thickness (LT), axial length, and anterior chamber depth were recorded and analyzed.

RESULTS

A total of 155 participants (179 eyes) were enrolled. The CER was significantly different among the three groups (CC: 1.245 vs. YAC: 1.060 vs. ARC: 1.029, P<0.001). The CER was found to be independently associated with both age (β=-0.011 (0.001), P<0.001) and LT (β=-0.049 (0.017), P=0.006) in the CC group, but it was only independently correlated with age (β=-0.004 (0.001), P=0.002) in the YAC group and LT (β=-0.014 (0.007), P=0.048) in the ARC group.

CONCLUSIONS

Capsulotomy enlargement can occur after femtosecond laser treatment in cataract surgery, especially in the non-adult group. Age was a determinant of the CER in CC and YAC groups, while LT was an independent determinant of the CER in CC and ARC groups. These two factors should be taken into consideration for more precise sized capsulotomy.

The creation of a corneal incision with a femtosecond laser

BACKGROUND: The cutting action of a femtosecond laser (FS-laser) on the corneal tissue is performed using a photodestructive effect. FS-laser technology is used in many different areas of corneal surgery, and studying this effect is an actual issue. AIM: To evaluate the surface of the corneal incision created by a FS-laser (experimental study). MATERIALS AND METHODS: 20 porcine eyes were divided into two groups (FS-laser and keratome). The corneal tissue surface in the area of contact between two lips of the incision was visualized by electron microscopy. RESULTS: In all cases, we received a full-thickness incisions through the cornea. Images obtained by electron microscopy showed regular surface, no signs of thermal or mechanical damage to the corneal structure. CONCLUSIONS: The FS-laser is used as a microscopic scalpel in surgery. The precision cutting process is performed by mechanical forces generated by photodestruction by expanding cavitation bubbles.

A transparent hydrophilic anti-biofouling coating for intraocular lens materials prepared by "bridging" of the intermediate adhesive layer

The attachment of bio-foulants, including unwanted cells, proteins, and bacteria, to a medical device such as an intraocular lens can lead to implantation failure. Hydrophilic polymers are often used as surface modifiers in the fabrication of anti-biofouling coatings, but a hydrophilic coating can easily become swollen and peel off the substrate. In this study, we chose polymethyl methacrylate (PMMA) as the representative material of intraocular lenses because PMMA has better biocompatibility, a higher refractive index, better optical clarity, lighter weight, more stable performance, and lower cost than other intraocular lens materials. We fabricated polyvinyl alcohol (PVA) coatings with or without a "bridge", that is, an intermediate adhesive layer (AL), to increase the adhesion bonding effect between the anti-biofouling coating and the substrate. The results indicated that the prepared coatings were transparent and noncytotoxic. Moreover, the anti-adhesion properties of the cells and the resistance properties to nonspecific protein adsorption of PMMA modified by both AL and PVA coatings were better and more durable compared with the sample only modified with a physically dipped PVA coating. The coating prepared by AL "bridging" provides a new strategy for the preparation of a transparent hydrophilic anti-biofouling coating suitable for PMMA intraocular lens materials.

Femtosecond Laser Assisted Cataract Surgery: A Review

Femtosecond laser assisted cataract surgery (FLACS) offers a level of precision, accuracy and customization that is not possible with manual phacoemulsification (MP). With the increase of patient expectations and premium intraocular lens utilization in the era of refractive cataract surgery, predictability and accuracy has become of utmost importance. FLACS has four main functions: creation of a consistently sized round capsulotomy, treatment of keratometric astigmatism with arcuate incisions, construction of clear corneal incisions, and fragmentation and/or softening of the lens. However, FLACS may have limitations due to suction loss, incomplete capsulotomy or poor pupillary dilation. Patient selection and surgeon experience is critical. This review article will focus on the various platforms available for FLACS, the steps in cataract surgery it can perform, and overall advantages and limitations of the technology.

Outcomes of Femtosecond Laser Assisted Cataract Surgery Performed by Resident and Attending Surgeons

Objective The study aimed to evaluate the safety and efficacy of resident surgeons performing femtosecond laser assisted cataract surgery (FLACS).

Methods A retrospective chart review was conducted at the University of Wisconsin-Madison from postgraduate year four residents performing FLACS between 2017 and 2019. Data were also collected from residents performing manual cataract surgery, and attending surgeons performing FLACS for comparison. Recorded data included patient demographics, pre- and postoperative visual acuity, pre- and postoperative spherical equivalent, nuclear sclerotic cataract grade, ocular and systemic comorbidities, intraocular lens, duration of surgery, cumulative dissipated energy (CDE), and intraoperative and postoperative complications.

Results A total of 90 cases were reviewed with 30 resident manual cases, 30 resident FLACS cases, and 30 attending FLACS cases. Resident manual (25.5 ± 6.8 minutes) and resident FLACS (17.5 ± 7.1 minutes) cases took a significantly longer time to complete compared with attending FLACS cases (13.6 ± 4.4 minutes; p < 0.001). There was higher CDE in resident FLACS and resident manual cases compared with attending FLACS cases, but the difference was not statistically significant (p = 0.06). Postoperative visual acuity was not statistically different at 1-day and 1-month after surgery among the three groups. Resident FLACS complications, which included one case requiring an intraoperative suture to close the wound, two cases with intraoperative corneal abrasions, two cases with postoperative ocular hypertension, and one case with cystoid macular edema, were not significantly greater than attending FLACS complications (p = 0.30).

Conclusion The FLACS performed by resident surgeons had comparable visual acuity outcomes to FLACS performed by attending surgeons, and to manual cataract surgery performed by resident surgeons. However, resident FLACS cases took significantly longer time to complete, and they were associated with a higher CDE and minor complication rate compared with attending FLACS cases. Introducing advanced technologies into surgical training curricula improves resident preparedness for independent practice, and this study suggests FLACS can be incorporated safely and effectively into resident education.

Ultrasound-Energy Consumption During Phases of Phacoemulsification of Nuclear Cataracts Using Femtosecond Laser: A Comparative Study

Purpose

To compare ultrasound (US) energy utilized in different phases of nuclear cataract removal in femtosecond laser-assisted cataract surgery (FLACS) with conventional phacoemulsification surgery (CPS) in relation to different nuclear densities.

Methods

A prospective nonrandomized comparative study was conducted at Ain Shams University and Al Watany Eye Hospital, Cairo, Egypt on 250 eyes with senile nuclear cataracts (NCs) of different nuclear densities (1-6). Eyes were divided into two groups - FLACS and CPS - and each group was subdivided according to cataract density into subgroups A (NC 1-2), B (NC 3-4) and C (NC 5-6). sextant-softened fragmentation patterns were assessed in the FLACS group and the quick-chop technique used in the CPS group. US energy required for nucleus cracking (EFX split) and for quadrant removal (EFX quadrant) was recorded.

Results

Total eyes included in the FLACS and CPS groups were 117 and 133, respectively. No significant differences between the groups for EFX quadrant and EFX split groups were observed (P=0.18 and P=0.49, respectively). For subgroup A, no significant difference was found between FLACS and CPS on EFX split (P=0.08) and EFX quadrant (P=0.49). For subgroup B, significantly lower values of EFX split (P=0.0001) and EFX quadrant (P<0.0001) were obtained with FLACS than CPS. For subgroup C, no significant difference was found for EFX split (P=0.86); however, EFX quadrant was significantly lower in the FLACS group (P=0.05).

Conclusion

FLACS lowers US energy utilized during quadrant removal at different nuclear densities, with highest significance in medium-density nuclear cataracts. Nucleus cracking by femtosecond laser is less effective in very hard cataracts. However, femtosecond-laser softening of hard nuclei is capable of of US-energy reduction during quadrant removal.

How Can We Improve Toric Intraocular Lens Calculation Methods? Current Insights

In this paper, we review current strategies for calculating toric intraocular lenses (IOLs). We discuss the prevalence and clinical relevance of astigmatism and the assessment of toric IOL candidates. We detail recommendations for evaluating astigmatism and current biometry and IOL power calculation techniques. Finally, error sources and results of current toric IOL calculators are discussed.

Preoperative intraocular pressure as a strong predictive factor for intraocular pressure rise during vacuum application in femtosecond laser-assisted cataract surgery

PURPOSE

To evaluate the effect of preoperative intraocular pressure (IOP) and the vacuum level on IOP during femtosecond laser-assisted cataract surgery.

METHODS

Intraocular pressure was measured in 40 enucleated porcine eyes by intracameral manometry prior, during and after vacuum application using the VICTUS femtosecond laser platform (Bausch&Lomb, Technolas Perfect Vision GmbH, Germany). Twenty combinations of different preoperative IOP levels (12, 16, 20 and 24 mmHg) and different vacuum levels (350-550 mbar) were investigated.

RESULTS

Multivariate regression analysis indicated that both the vacuum level (beta = 0.138; p < 0.001) but much stronger the preoperative IOP (beta = 0.861; p < 0.001) were predictive factors for IOP rise during vacuum application. Mean IOP was 28.23 ± 3.86, 34.23 ± 3.92, 40.35 ± 4.41 and 46.82 ± 4.11 mmHg in groups with baseline IOP of 12, 16, 20 and 24 mmHg, respectively. In the 350, 450 and 550 mbar group, and mean IOP was 35.85 ± 7.85, 37.33 ± 7.90 and 39.00 ± 8.04 mmHg, respectively. Lowering the preoperative IOP by 2 mmHg and reducing the vacuum from maximum to minimum resulted in a similar reduction in IOP during vacuum application (-3.10 ± 0.79 mmHg versus -3.15 ± 0.88 mmHg; p = 0.015). Furthermore, decreasing the baseline IOP from 20 to 12 mmHg resulted in a 30.0% reduction in intraoperative IOP.

CONCLUSION

Preoperative IOP was a stronger predictive factor for intraoperative IOP rise than the applied vacuum level. Measurements and critical interpretation of preoperative IOP in a preliminary examination could help estimating the individual risk of significant IOP rise during femtosecond laser-assisted cataract surgery and could help taking early countermeasures in selected cases. Due to the porcine ex vivo model, further studies are needed to verify these findings.

Unilateral Refractive Lens Exchange with a Multifocal Intraocular Lens in Emmetropic Presbyopic Patients

Purpose: To evaluate the visual outcome and patient satisfaction after a unilateral multifocal IOL implantation in the non-dominant eye of emmetropic patients with presbyopia. Methods: An interventional case series of consecutive patients who underwent unilateral phacoemulsification with femto-laser assisted cataract surgery (FLACS) and refractive lens exchange (RLE), followed by an implantation of a trifocal diffractive IOL (FineVision Micro F), was performed in the non-dominant eyes of emmetropic patients with presbyopia. After 6 months of follow-up, the main outcome measures were uncorrected distance visual acuity (UDVA), uncorrected intermediate visual acuity (UIVA), and uncorrected near visual acuity (UNVA). Secondary outcomes included spherical equivalent (SE), refraction, contrast sensitivity, patient questionnaire and presence of visual side effects. Results: A total of 26 eyes of 26 patients, with an average age of 53.8 ± 4.1 years, were included in this study. Preoperative mean UDVA was 0.13 ± 0.04 logMAR (Snellen 20/27), UIVA was 0.46 ± 0.12 logMAR (Snellen 20/58), and UNVA was 0.66 ± 0.17 logMAR (Snellen 20/91), in comparison to postoperative mean UDVA of 0.18 ± 0.32 logMAR (Snellen 20/30) (p = 0.32), UIVA of 0.17 ± 0.21 logMAR (Snellen 20/30) (p < 0.005), and UNVA of 0.02 ± 0.10 logMAR (Snellen 20/21) (p < 0.005). Monocular UNVA of 20/25 or better in the operated eye was achieved in 23 (88%) patients. Twenty-four (96%) patients said they would recommend this procedure to family and friends. There were no intraoperative complications and no IOL exchange was required. Conclusions: A unilateral RLE of the non-dominant eye with FLACS and a trifocal diffractive IOL (FineVision Micro F) implantation in emmetropic, presbyopic patients is provides satisfactory distance, intermediate, and near visual outcomes with no complications reported in this preliminary case series.

Effect of lens thickness and nuclear density on the amount of laser fragmentation energy delivered during femtosecond laser-assisted cataract surgery

PURPOSE

To study the influence of lens thickness and nuclear density on the amount of laser fragmentation energy delivered during femtosecond laser-assisted cataract surgery.

SETTING

Ain Shams University and Al-Watany Eye Hospital, Cairo, Egypt.

DESIGN

Retrospective case series.

METHODS

This study included eyes of patients with primary cataract of different nuclear densities that had femtosecond laser-assisted cataract surgery using the Catalys Precision system. Variables studied included preoperative lens thickness measured by spectral-domain optical coherence tomography, nuclear density using the Lens Opacities Classification System III, pupil size, laser fragmentation energy, total laser energy, and transversal ultrasound time (Ellips FX). Patients were divided according to the preoperative lens thickness as follows: lens thickness more than 4.8 mm (Group 1) and lens thickness 4.8 mm or less (Group 2).

RESULTS

The study included 192 eyes of 120 patients. The amount of laser energy for fragmentation was statistically significantly higher in Group 1 than in Group 2 (5.9 J ± 1.5 [SD] versus 4.5 ± 1.8 J) (P < .001). Laser fragmentation energy and total laser time had a strong positive correlation with lens thickness (r = 0.53, P < .001) but not with nuclear density or pupil size. Lens thickness was positively correlated with age (r = 0.42, P < .001) but not with nuclear density.

CONCLUSIONS

The preoperative lens thickness, not density, determined the amount of laser energy delivered. The laser might deliver unnecessary energy for softer and thicker nuclei while delivering less energy for thinner but harder nuclei.

Lens capsule-related complications of femtosecond laser-assisted capsulotomy versus manual capsulorhexis for white cataracts

PURPOSE

Comparison of lens capsule-related complications resulting from femtosecond laser-assisted capsulotomy and manual capsulorhexis in patients with white cataracts.

SETTING

Eye Center, Second Affiliated Hospital, Zhejiang Medical School, Hangzhou, China.

DESIGN

Prospective consecutive nonrandomized comparative cohort study.

METHODS

Selected patients were divided into a femtosecond laser-assisted cataract surgery group (FLACS group) and a conventional phacoemulsification cataract surgery group (CPCS group). Each case was recorded as either a type I or type II white cataract. Here, type I was characterized by the presence of a liquefied cortex, whereas type II had a solid cortex. Five experienced phacoemulsification surgeons conducted all surgeries. Lens capsule-related events, including anterior capsule tears, posterior capsule ruptures (PCRs), incomplete capsulotomies, and irregular capsulorhexes were recorded; surgical parameters, postoperative visual acuities, and intraocular lens (IOL) decentrations were evaluated.

RESULTS

The study comprised 132 eyes of 132 patients (66 in each group). Anterior capsule tears were significantly more common in the CPCS group than the FLACS group (12.1% versus 0%). All 8 cases of anterior capsule tears were type I cases. Six FLACS cases developed incomplete capsulotomies, four of which were type I cases. The incidences of PCRs and vitreous loss were the same. Capsulotomy produced better circularity index and diameter stability than capsulorhexis. IOLs were better centered in the FLACS group than the CPCS group. The mean ultrasound power, absolute phaco time, effective phaco time, and postoperative visual acuities were similar in both groups.

CONCLUSIONS

Compared with CPCS, FLACS decreased the risk for anterior capsule tears in white cataracts, especially in type I cases. However, it did not reduce the incidence of PCR. Incomplete capsulotomy during FLACS could happen in white cataracts. Using FLACS on white cataracts enabled more precise capsulotomies and better-centered IOLs.

Comparison of Surgically Induced Astigmatism and Morphologic Features Resulting From Femtosecond Laser and Manual Clear Corneal Incisions for Cataract Surgery

PURPOSE

To compare the surgically induced astigmatism (SIA) vector, flattening effect, torque, and wound architecture following femtosecond laser and manual clear corneal incisions (CCIs).

METHODS

In a double-armed, randomized, prospective case series, cataract surgery was performed for 600 eyes using femtosecond laser (300 eyes) or manual (300 eyes) 2.4-mm CCIs in temporal or superior oblique locations. SIA, flattening effect, torque, and the summated vector mean for SIA were calculated. Correlation with individual features was established and incision morphology was investigated by anterior segment optical coherence tomography at 3 months of follow-up.

RESULTS

The SIA, flattening effect, and torque were lower in the femtosecond laser group for both incision locations, although the differences were not significant (all P > .05). The femtosecond laser group showed less dispersion of SIA magnitude and flattening effect. Temporal and superior oblique incisions resulted in flattening effect values of -0.11 and -0.21 diopters (D), respectively, in the femtosecond laser group and -0.13 and -0.34 D, respectively, in the manual group. Significant correlations with individual features were only found in the femtosecond laser group, with preoperative astigmatism being the only significant SIA predictor by multiple regression analysis (P = .003). Femtosecond laser CCIs showed less deviation from the intended length, wound enlargement, endothelial misalignment, and Descemet membrane detachments (all P < .037).

CONCLUSIONS

Femtosecond laser CCIs were more reproducible. Although SIAs were smaller in femtosecond laser CCIs than in manual CCIs for both temporal and superior oblique incisions, the difference was not statistically significant. Association with individual features is highly variable. [J Refract Surg. 2018;34(5):322-329.].

Comparison of Wound Sealability Between Femtosecond Laser-Constructed and Manual Clear Corneal Incisions in Patients Undergoing Cataract Surgery: A Pilot Study

PURPOSE

To compare the sealability of femtosecond laser-constructed and manual clear corneal incisions (CCIs) in patients undergoing cataract surgery.

METHODS

This prospective, randomized study included 62 eyes of 62 patients with cataract grade 1 to 2 (LOCS scale). The patients were randomly assigned (1:1) for creation of either manual CCI (with a 2.4-mm keratome) or femtosecond laser-assisted CCI (LENSAR, Inc., Orlando, FL) (31 eyes in each group) before undergoing femtosecond laser-assisted cataract surgery. Wound sealability was assessed as grade 1, 2, or 3 (1: need to reform anterior chamber and hydrate wound at end of surgery; 2: need to reform anterior chamber only; 3: formed anterior chamber, no hydration or anterior chamber reformation necessary).

RESULTS

The nuclear sclerosis grade, cumulative dissipated energy and phacoemulsification time were comparable between the two groups. No complications were experienced in any of the patients. The mean wound sealability for the femtosecond laser group (2.35 ± 0.84) was statistically significantly better in comparison to the manual group (1.32 ± 0.65) (P < .001). At the end of the surgery, 22.6% (n = 7) of eyes in the femtosecond laser group needed reformation of the anterior chamber and hydration of the wound compared to 77.4% (n = 24) of eyes in the manual group. Conversely, 58.1% (n = 18) of eyes in the femtosecond laser group compared to 9.7% (n = 3) of eyes in the manual group were observed to have a formed anterior chamber.

CONCLUSIONS

Femtosecond laser-created CCIs had significantly better wound sealability compared to those created with a metal keratome. [J Refract Surg. 2017;33(11):744-748.].

[Morphological and clinical aspects of anterior capsulotomy in femtosecond laser-assisted cataract surgery]

The review covers morphological and clinical aspects of femtosecond laser-assisted anterior capsulotomy in cataract surgery. Literature data suggests that femtosecond laser-assisted capsulotomy is more accurate in size, shape, and centration than manual. Femtosecond laser-assisted anterior capsulotomy improves the accuracy of IOL positioning within the capsular bag.

Human lens epithelial cell apoptosis and epithelial to mesenchymal transition in femtosecond laser-assisted cataract surgery

AIM

To evaluate human lens epithelium cell apoptosis and epithelial to mesenchymal transition (EMT) induced by femtosecond laser in femtosecond laser assisted cataract surgery (FLACS).

METHODS

Sixty cataract patients with N2 to N3 stage according to the LOCS III were enrolled in this study and divided into three groups randomly: FLACS1 group (cataract surgery by FLACS with LenSx), FLACS2 group (cataract surgery by FLACS with LensAR) and manual group (cataract surgery by phacoemulsification). Patients in two FLACS groups performed anterior capsulotomy by LenSx or LensAR laser system. Patients in the manual group were performed continuous curvilinear capsulorrhexis (CCC) manually. The anterior capsules were fixed right after moved out of eye. Hematoxylin-eosine staining, immunofluorescence staining and real-time PCR were performed in order to observe human lens epithelium cells changes after cataract surgery.

RESULTS

The capsule cutting edge was shown irregularity and roughness in two FLACS groups and smooth edge in manual capsulotomy by pathologic staining. Irregularities of the cell configuration with partly swollen and destroyed nuclei were observed in two FLACS groups. Femtosecond laser could induce a significantly higher cell apoptosis in human lens epithelium cell than manually performed CCC (P<0.05). Lens epithelium cells apoptosis were correlated with femtosecond laser duration according to Pearson correlation analysis. Decreased N-cadherin expression, alpha-SMA and FSP-1 level in two FLACS groups showed the inhibition of cell EMT.

CONCLUSION

Femtosecond laser may affect the apoptosis and EMT of lens epithelium cells which are under the peeled central lens capsule.

Anterior Capsule of the Lens: Comparison of Morphological Properties and Apoptosis Induction following FLACS and Standard Phacoemulsification Surgery

Purpose

Comparative evaluation of morphological features of anterior capsules and apoptosis induction in epithelial cells after femtosecond laser-assisted cataract surgery (FLACS) and standard phacoemulsification surgery.

Methods

Group 1: 30 FLACS anterior capsulotomies and Group 2: 30 manual anterior continuous curvilinear capsulorhexes. All patients were operated on by the same experienced surgeon. Morphological features of the anterior capsules and apoptosis induction in epithelial cells were evaluated.

Results

All patients revealed a significant mean best-corrected visual acuity (BCVA) improvement 3 months after surgery, and no major intraoperative nor postoperative complications occurred. The capsular epithelium appeared to be preserved in both groups. Scanning electron microscopy analysis revealed irregular saw-tooth shaped edges in capsules from Group 1 whereas capsules from Group 2 showed regular and smooth edges. A statistically significant higher expression of the downstream apoptotic effector cleaved caspase 3 was observed in Group 1.

Conclusions

The saw-tooth appearance was likely due to the progressive sequence of laser pulses on the capsule. The low energy/high frequency properties of the laser pulse, combined with an overlapped pulse pattern, resulted in highly continuous morphology of capsule edges. The higher apoptosis induction in FLACS group might be due to photodisruption-dependent plasma generation and formation of cavitation bubbles.

Retinal and choroidal thickness after femtosecond laser-assisted and standard phacoemulsification

Purpose

The purpose of this study was to compare the short-term changes in retina and choroidal tissue after femtosecond laser-assisted cataract surgery (FLACS) and standard phacoemulsification (PE) surgery.

Methods

In all, 25 eyes undergoing FLACS and 27 eyes undergoing PE surgery were included in this nonrandomized, retrospective, cross-sectional study. Central retinal thickness (CRT) and choroidal thickness (CT) were measured pre- and postoperatively (at day 1, 1 week later, and after 1 month) with spectral domain optical coherence tomography (OCT) in all patients and were compared. For group comparisons, chi-square test and independent t-test were used. Postoperative values were compared to the baseline using a paired t-test. The magnitude of the change from baseline to the peak was analyzed by multiple regression models in an attempt to explain possible influence variables.

Results

Pre and postoperative CRT measurements were similar in both groups. The mean subfoveal CT at day 1, after 1 week, and 1 month were significantly higher than baseline CT measurements in the PE group.

Conclusion

FLACS might have an advantage in regard to postoperative choroidal changes.

Preliminary Results of Femtosecond Laser-assisted Cataract Surgery in a Private Clinic in Iran

Purpose:

To report the preliminary results of femtosecond laser-assisted cataract surgery in Iranian patients.

Methods:

This prospective case series included 21 eyes of 21 patients with cataract. Mean patient age was 66.7 ± 10 years. The patients underwent femtosecond-laser assisted cataract surgery (VICTUS Femtosecond Laser Platform: Bausch + Lomb) and intraocular lens (IOL) implementation in Bina Eye Hospital, Tehran, Iran between May and October, 2014. Visual outcomes, intraocular pressure (IOP), and complications were evaluated three months after surgery.

Results:

Mean preoperative best-spectacle corrected visual acuity (BSCVA) was 0.40 ± 0.21 logMAR which significantly improved to 0.02 ± 0.03 logMAR three months postoperatively (P < 0.001). Mean preoperative IOP was 17.88 ± 2.70 mmHg which significantly decreased to 12.5 ± 1.51 mmHg three months after operation (P < 0.001). Mean duration of operation for these patients was 29.30 ± 8 minutes and mean femtosecond laser process time was 4.20 ± 2 minutes. In terms of complications, 9 patients developed fine subconjunctival hemorrhage and eye redness and 2 patients had mild corneal edema which all subsided within less than 7 days. Serious complications such as anterior or posterior capsule tears were not encountered.

Conclusion:

Femtosecond laser-assisted cataract surgery is a relatively new method of cataract

Resident surgeon efficiency in femtosecond laser-assisted cataract surgery

Purpose

Comparison of resident surgeon performance efficiencies in femtosecond laser-assisted cataract surgery (FLACS) versus conventional phacoemulsification.

Patients and methods

A retrospective cohort study was conducted on consecutive patients undergoing phacoemulsification cataract surgery performed by senior ophthalmology residents under the supervision of 1 attending physician during a 9-month period in a large Veterans Affairs medical center. Medical records were reviewed for demographic information, preoperative nucleus grade, femtosecond laser pretreatment, operative procedure times, total operating room times, and surgical complications. Review of digital video records provided quantitative interval measurements of core steps of the procedures, including completion of incisions, anterior capsulotomy, nucleus removal, cortical removal, and intraocular lens implantation.

Results

Total room time, operation time, and corneal incision completion time were found to be significantly longer in the femtosecond laser group versus the traditional phacoemulsification group (each P<0.05). Mean duration for manual completion of anterior capsulotomy was shorter in the laser group (P<0.001). There were no statistically significant differences in the individual steps of nucleus removal, cortical removal, or intraocular lens placement. Surgical complication rates were not significantly different between the groups.

Conclusion

In early cases, resident completion of femtosecond cataract surgery is generally less efficient when trainees have more experience with traditional phacoemulsification. FLACS was found to have a significant advantage in completion of capsulotomy, but subsequent surgical steps were not shorter or longer. Resident learning curve for the FLACS technology may partially explain the disparities of performance. Educators should be cognizant of a potential for lower procedural efficiency when introducing FLACS into resident training.

A Review of Laser-Assisted Versus Traditional Phacoemulsification Cataract Surgery

The use of femtosecond laser surgery improves the precision and reproducibility of corneal incisions and the capsular opening; it also reduces the amount of ultrasound energy required for lens nucleus work-up. The rate of complications reported so far appears to be low. There are a number of contraindications such as a history of cornea and/or glaucoma surgery and certain anatomical features like deep-set eyes, kyphosis, tremor, and obesity. Visual recovery and refractive results of both techniques are excellent. Comparing laser cataract surgery (LCS) with manual cataract surgery (conventional phacoemulsification) based on meta-analysis currently reveals slight differences in refractive and visual outcome. Both methods are extremely successful and safe. LCS is a technique still on the rise, with its full potential not yet tapped.

Surface Modification of Intraocular Lenses

Objective:

This paper aimed to review the current literature on the surface modification of intraocular lenses (IOLs).

Data Sources:

All articles about surface modification of IOLs published up to 2015 were identified through a literature search on both PubMed and ScienceDirect.

Study Selection:

The articles on the surface modification of IOLs were included, but those on design modification and surface coating were excluded.

Results:

Technology of surface modification included plasma, ion beam, layer-by-layer self-assembly, ultraviolet radiation, and ozone. The main molecules introduced into IOLs surface were poly (ethylene glycol), polyhedral oligomeric silsesquioxane, 2-methacryloyloxyethyl phosphorylcholine, TiO₂, heparin, F-heparin, titanium, titanium nitride, vinyl pyrrolidone, and inhibitors of cytokines. The surface modification either resulted in a more hydrophobic lens, a more hydrophilic lens, or a lens with a hydrophilic anterior and hydrophobic posterior surface. Advances in research regarding surface modification of IOLs had led to a better biocompatibility in both in vitro and animal experiments.

Conclusion:

The surface modification is an efficient, convenient, economic and promising method to improve the biocompatibility of IOLs.

Descemet Membrane Detachment in Femtosecond Laser-Assisted Cataract Surgery

PURPOSE

To report a case series of 4 patients with Descemet membrane detachment (DMD) after undergoing femtosecond laser-assisted cataract surgery incisions.

METHODS

Case report.

RESULTS

DMD was noted at the secondary incision (n = 2) or at the main incision (n = 2). All the secondary incision and 1 main incision DMD were resolved with intraoperative maneuvers. Delay in recognizing DMD intraoperatively at the principal incision in 1 case led to inadvertent aspiration of a part of it and persistent postoperative corneal edema. This complication was handled with Descemet membrane endothelial keratoplasty 1 month after initial surgery.

CONCLUSIONS

DMD can occur after femtosecond laser-assisted cataract surgery, although it is a rare complication as it is in traditional phacoemulsification. The surgeon must be prepared to recognize it, manage it intraoperatively, and treat it postoperatively to reduce the risk of permanent damage to the eye.

Update and clinical utility of the LenSx femtosecond laser in cataract surgery

The introduction of femtosecond lasers to cataract surgery has been the major disruptive technology introduced into ophthalmic surgery in the last decade. Femtosecond laser cataract surgery (FLACS) integrates high-resolution anterior segment imaging with a femtosecond laser allowing key steps of cataract surgery to be performed with computer-guided laser accuracy, precision, and reproducibility. Since the introduction of FLACS, there have been significant advances in laser software and hardware as well as surgeon experience, with over 250 articles published in the peer-reviewed literature. This review examines the published evidence relating to the LenSx platform and discusses surgical techniques, indications, safety, and clinical results.

Profitability analysis of a femtosecond laser system for cataract surgery using a fuzzy logic approach

AIM

To define the financial and management conditions required to introduce a femtosecond laser system for cataract surgery in a clinic using a fuzzy logic approach.

METHODS

In the simulation performed in the current study, the costs associated to the acquisition and use of a commercially available femtosecond laser platform for cataract surgery (VICTUS, TECHNOLAS Perfect Vision GmbH, Bausch & Lomb, Munich, Germany) during a period of 5y were considered. A sensitivity analysis was performed considering such costs and the countable amortization of the system during this 5y period. Furthermore, a fuzzy logic analysis was used to obtain an estimation of the money income associated to each femtosecond laser-assisted cataract surgery (G).

RESULTS

According to the sensitivity analysis, the femtosecond laser system under evaluation can be profitable if 1400 cataract surgeries are performed per year and if each surgery can be invoiced more than $500. In contrast, the fuzzy logic analysis confirmed that the patient had to pay more per surgery, between $661.8 and $667.4 per surgery, without considering the cost of the intraocular lens (IOL).

CONCLUSION

A profitability of femtosecond laser systems for cataract surgery can be obtained after a detailed financial analysis, especially in those centers with large volumes of patients. The cost of the surgery for patients should be adapted to the real flow of patients with the ability of paying a reasonable range of cost.

Emerging Technology in Refractive Cataract Surgery

Technology in cataract surgery is constantly evolving to meet the goals of both surgeons and patients. Recent major advances in refractive cataract surgery include innovations in preoperative and intraoperative diagnostics, femtosecond laser-assisted cataract surgery (FLACS), and a new generation of intraocular lenses (IOLs). This paper presents the latest technologies in each of these major categories and discusses how these contributions serve to improve cataract surgery outcomes in a safe, effective, and predictable manner.

Correlation between anterior chamber characteristics and laser flare photometry immediately after femtosecond laser treatment before phacoemulsification

PurposeTo assess the anterior chamber (AC) characteristics and its correlation to laser flare photometry immediately after femtosecond laser-assisted capsulotomy and photodisruption.Patients and methodsThe study included 97 cataract eyes (n=97, mean age 68.6 years) undergoing femtosecond laser-assisted cataract surgery (FLACS). Three cohorts were analysed relating to the flare photometry directly post femtosecond laser treatment (flare <100 n=28, 69.6±7 years; flare 100-249 n=47, 67.7±8 years; flare >249 photon counts per ms cohort n=22, 68.5±10 years). Flare photometry (KOWA FM-700), corneal topography (Oculus Pentacam, Germany: AC depth, volume, angle, pachymetry), axial length, pupil diameter, and endothelial cells were assessed before FLACS, immediately after femtosecond laser treatment and 1 day postoperative (LenSx Alcon, USA). Statistical data were analysed by SPSS v19.0, Inc.ResultsThe AC depth, AC volume, AC angle, central and thinnest corneal thickness showed a significant difference between flare <100 vs flare 100-249 10 min post femtosecond laser procedure (P=0.002, P=0.023, P=0.007, P=0.003, P=0.011, respectively). The AC depth, AC volume, and AC angle were significantly larger (P=0.001, P=0.007, P=0.003, respectively) in the flare <100 vs flare >249 cohort 10 min post femtosecond laser treatment.ConclusionsA flat AC, low AC volume, and a narrow AC angle were parameters associated with higher intraocular inflammation. These criteria could be used for patient selection in FLACS to reduce postoperative intraocular inflammation.

Advances in femtosecond laser technology

Femtosecond laser technology has become widely adopted by ophthalmic surgeons. The purpose of this study is to discuss applications and advantages of femtosecond lasers over traditional manual techniques, and related unique complications in cataract surgery and corneal refractive surgical procedures, including: LASIK flap creation, intracorneal ring segment implantation, presbyopic treatments, keratoplasty, astigmatic keratotomy, and intrastromal lenticule procedures.

Effects of lentiviral RNA interference-mediated downregulation of integrin-linked kinase on biological behaviors of human lens epithelial cells

AIM

To investigate the effects of lentivirus (LV) mediated integrin-linked kinase (ILK) RNA interference (RNAi) on biological behaviors of human lens epithelial cells (LECs).

METHODS

Human cataract LECs and immortalized human LEC line, human lens epithelial (HLE) B-3 cells were transfected by lentiviral vector expressing ILK-specific short hairpin RNA (shRNA) and then stimulated by transforming growth factor-β (TGF-β), the silencing of ILK gene and protein was identified by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot methods; biological behaviors including cell cycle and apoptosis, cell morphology, α-smooth muscle actin (SMA) stress fiber formation and cell migration were examined.

RESULTS

Remarkable decreases of ILK protein expression were detected in LECs carrying lentiviral ILK-shRNA vector; flow cytometry revealed arresting of cell cycle progression through the G1/S transition and higher apoptosis rate in ILK-RNAi-LV transfected cells. Less α-SMA stress fiber formation and migration was observed in ILK-RNAi-LV transfected LECs.

CONCLUSION

The present study demonstrated that ILK was an important regulator for LECs proliferation and migration. LV mediated ILK RNAi is an effective way to decrease ILK-regulated cell growth by arresting cell cycle progression and increasing cell apoptosis, as well as, to prevent cell migration by inhibiting TGF-β induced α-SMA stress fiber formation. Thus, LV mediated ILK RNAi might be useful to prevent posterior capsular opacification.

Comparative outcomes of femtosecond laser-assisted cataract surgery and manual phacoemusification: a six-month follow-up

BACKGROUND

To explore efficacy and safety outcomes in patients undergoing femtosecond laser-assisted cataract surgery (FLACS) versus manual phacoemulsification cataract surgery (PCS).

DESIGN

Prospective consecutive nonrandomized comparative cohort study.

PARTICIPANTS

A total of 124 eyes from 106 patients (70 in FLACS and 54 in PCS).

METHODS

Comparison of FLACS with PCS over 6 months.

MAIN OUTCOME MEASURES

Macular central subfield thickness (CST), cube volume (CV), cube average thickness (CAT), endothelial cell density (ECD), central corneal thickness (CCT) and photon count value (PCV).

RESULTS

CST, CV and CAT increased postoperatively, which did not return to preoperative levels by 6 months. The values were similar between groups throughout the follow-up, and comparison of changes from baseline also showed no significant difference. Preoperative ECD showed significant difference, which decreased postoperatively and remained stable during follow-up, being lowest at 1 month. FLACS had greater endothelial cell loss than PCS, which was not significant. CCT in both groups increased, reaching maximum on day one and tended to decrease thereafter. No significant differences were found regarding postoperative values and the mean increase. In both groups, mean PCV increased from preoperatively to day one, week one and month one. Flare values in FLACS were lower than PCS, reaching statistical significance at 6 months (P = 0.001). However, the differences in changes of PCV were not significantly different at any visit.

CONCLUSIONS

Both FLACS and PCS achieved similar safety and efficacy outcomes for performing cataract surgery. Flare values in eyes with FLACS were lower than those with PCS at 6 months postoperatively.

One-Day Use of Preoperative Topical Nonsteroidal Anti-Inflammatory Drug Prevents Intraoperative Prostaglandin Level Elevation During Femtosecond Laser-Assisted Cataract Surgery

PURPOSE

To determine if pretreatment with topical nonsteroidal anti-inflammatory drug (NSAID) prior to femtosecond laser-assisted cataract surgery (FLACS) prevents intraoperative prostaglandin level elevation as a potential risk factor of postoperative complications.

PATIENTS AND METHODS

Thirty-six patients with clinically significant cataract and without any concomitant general or ophthalmic disease were enrolled into the three age-matched groups of the study. The mean age of the patients was 62.3 ± 13.1 years. The first group of patients underwent traditional phacoemulsification (Control group), on the second group of patients FLACS was performed, and the third group of patients received topical 0.1% nepafenac pretreatment for 1one day prior to FLACS. Before the phacoemulsification part of the cataract surgery, approximately 110 µL of aqueous humor was collected in all groups. Total prostaglandin concentrations of the collected aqueous humor samples were evaluated by enzyme immunoassay (EIA).

RESULTS

The mean of the total prostaglandin concentrations of the aqueous humor samples was 208.8 ± 140.5 pg/mL in patients in the control group, 1449.1 ± 1019.7 pg/mL in the FLACS group (p > 0.001), and 92.2 ± 51.7 pg/mL in the group pretreated with topical NSAID before the FLACS (p > 0.001 compared to FLACS; p > 0.01 compared to control), respectively.

CONCLUSIONS

FLACS surgery increases intracameral prostaglandin concentration. However, using preoperative 1-day-long nonsteroid anti-inflammatory drops prior to FLACS, this intraoperative increase diminishes. Our study raises the possibility that NSAID pretreatment may be routinely administered before FLACS cataract surgeries to achieve a further decrease in the potential complications of increased total prostaglandin concentration during FLACS surgeries.

Changes in Aqueous Humor pH After Femtosecond Laser-Assisted Cataract Surgery

PURPOSE

To compare aqueous humor pH values in patients during femtosecond laser-assisted cataract surgery with patients during conventional phacoemulsification.

METHODS

A prospective clinical study was conducted in 29 eyes of 29 patients who underwent cataract surgery by a single surgeon. The femtosecond laser group included 15 eyes operated on with a femtosecond laser platform (Catalys; Abbott Medical Optics, Santa Ana, CA) and the phacoemulsification group included 14 eyes that were operated on with conventional phacoemulsification. The femtosecond laser group was subdivided into low, medium, and high level of cavitation gas bubbles after docking and the femtosecond laser procedure, according to the judgment of the surgeon. Aqueous humor samples (0.10 to 0.15 mL) were collected through a paracentesis from each patient after docking, corneal incisions, and nucleus fragmentation in the femtosecond laser group and after corneal incisions but before injection of viscoelastic in the phacoemulsification group, then analyzed with a pH meter.

RESULTS

The mean pH was 6.53 ± 0.09 (range: 6.42 to 6.70) and 7.42 ± 0.07 (range: 7.28 to 7.48) in the femtosecond laser and phacoemulsification groups, respectively (P < .001). In the femtosecond laser group, no significant differences in pH were observed between the three subgroups after docking and the femtosecond laser surgical procedure: low (6.55 ± 0.09 [range: 6.53 to 6.57]), medium (6.54 ± 0.07 [range: 6.52 to 6.55]), and high (6.42 ± 0.00 [range: 6.40 to 6.44]) level of gas bubbles.

CONCLUSIONS

Cavitation bubbles derived from the photodisruption process in femtosecond laser-assisted cataract surgery lead to an acidic shift of the aqueous humor pH as a result of the transformation of carbon dioxide to carbonic acid. The level of gas bubbles visible after the laser photodisruption does not seem to correlate with this pH shift. Further analysis of femtosecond laser-assisted cataract surgery is necessary.

The evolution of corneal and refractive surgery with the femtosecond laser

The use of femtosecond lasers has created an evolution in modern corneal and refractive surgery. With accuracy, safety, and repeatability, eye surgeons can utilize the femtosecond laser in almost all anterior refractive procedures; laser in situ keratomileusis (LASIK), small incision lenticule extraction (SMILE), penetrating keratoplasty (PKP), insertion of intracorneal ring segments, anterior and posterior lamellar keratoplasty (Deep anterior lamellar keratoplasty (DALK) and Descemet's stripping endothelial keratoplasty (DSEK)), insertion of corneal inlays and cataract surgery. As the technology matures, it will push surgical limits and open new avenues for ophthalmic intervention in areas not yet explored. As we witness the transition from femto-LASIK to femto-cataract surgery it becomes obvious that this innovation is here to stay. This article presents some of the most relevant advances of femtosecond lasers to modern corneal and refractive surgery.

Femtosecond laser cataract surgery

Femtosecond laser (FSL) cataract surgery is in its infancy but is rapidly gaining popularity due to the improved consistency and predictability for corneal incisions and anterior capsulorhexis. It enables subsequently less phacoemulsification energy and time to be employed, which has gains in terms of reduced corneal oedema. In addition, the FSL allows better circularity of the anterior capsulotomy, capsule overlap, intraocular lens (IOL) placement and centration of the IOL. These advantages have resulted in improved visual and refractive outcomes in the short term. Complication rates are low which reduce with surgeon experience. This review article focuses on the Alcon LenSx system.

[Results of femtosecond laser-assisted cataract surgery using the new 2.16 software and the SoftFit® Patient Interface]

INTRODUCTION

Femtosecond laser-assisted cataract surgery improved the results of cataract surgeries.

AIM

Outcome analysis of femtosecond laser-assisted cataract surgery using the novel 2.16 software and the SoftFit(®) Patient Interface.

METHOD

The novel software and the newly developed Patient Interface were used in 100 eyes of 100 patients.

RESULTS

Length of femtosecond laser pretreatment decreased to 45-60 seconds. The smaller size of the new patient interface resulted in easier docking even on pediatric eyes. Suction force used for docking decreased from 40-50 mmHg to 16-20 mmHg. Incidence rate of subconjunctival suffusion decreased from 40% to 15-20% and its clinical severity was reduced, too. No corneal microfolds evolved, thus the incidence rate of the free-floating capsulotomies increased from 30% to 97%. The total energy of femtosecond laser pretreatment was decreased by almost 50%. Corneal wounds had the desired structure, and they were easy to open and closed precisely.

CONCLUSIONS

The SoftFit(®) patient interface and the novel software widened the possible uses of the femtosecond laser-assisted cataract surgery, e.g. in pediatric ophthalmology. Innovations improved the safety and the predictability of the method.

Evaluation of the toric implantable collamer lens for simultaneous treatment of myopia and astigmatism

Myopic astigmatism is a prevalent condition that can be treated with spectacles, contact lenses, or laser refractive surgery. However, these treatment options have functional limitations at higher levels of refractive error. The toric implantable collamer lens is designed to treat a broad range of refractive error, generally up to -18 diopters with +1 to +6 diopters of astigmatism. Approval for a more limited treatment range of up to 15 diopters of myopia with +1 to +4 diopters of astigmatism is being sought in the US, where this device has not yet received marketing approval. Surgical correction of high-myopic astigmatism can be life-altering and allow people to participate in activities that were not previously feasible because of visual limitations. The toric implantable collamer lens is implanted behind the iris and in front of the natural crystalline lens. With earlier lens designs, it was necessary to create an iridectomy or iridotomy to prevent pupillary block. The newest toric implantable collamer lens model has a small central hole that is not visually noticeable. This eliminates the need to create a hole in the iris, thereby enhancing the safety of the procedure.

Corrective Techniques and Future Directions for Treatment of Residual Refractive Error Following Cataract Surgery

Postoperative residual refractive error following cataract surgery is not an uncommon occurrence for a large proportion of modern-day patients. Residual refractive errors can be broadly classified into 3 main categories: myopic, hyperopic, and astigmatic. The degree to which a residual refractive error adversely affects a patient is dependent on the magnitude of the error, as well as the specific type of intraocular lens the patient possesses. There are a variety of strategies for resolving residual refractive errors that must be individualized for each specific patient scenario. In this review, the authors discuss contemporary methods for rectification of residual refractive error, along with their respective indications/contraindications, and efficacies.