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

Femtosecond laser-assisted cataract surgery for complex cataracts - A review

Since its inception in 2009, femtosecond laser-assisted cataract surgery (FLACS) has become an alternative to conventional phacoemulsification cataract surgery (CPCS). Clinical studies were unable to demonstrate superior visual outcomes, but revealed reduced endothelial cell loss. More recently, the cost-effectiveness of FLACS over CPCS in routine cataract surgeries has been challenged. However, the unique abilities of FLACS to customize anterior capsulotomies precisely, soften and fragment the nucleus without capsular bag stress, and create corneal incisions may have special utility in complex cataract and less-common scenarios. In this article, we review the unique role of FLACS in complex cataract surgeries and how it could play a role to improve the safety and predictability of nonroutine cataract surgery.

Preventing the Argentinian flag sign and managing anterior capsular tears: A review

The Argentinian flag sign (AFS) is a feared complication during cataract extraction. Intralenticular pressures, especially excessive posterior pressure, have been identified as potential mechanisms for capsular stress and tearing associated with AFS. Capsular tension is created by positive intralenticular pressures, which cause the irido-lens diaphragm to move anteriorly once the manual capsulorhexis has been initiated. This tension can cause inadvertent tears that self-propagate to the lens equator, causing an AFS, among other intraoperative complications. Thus, this review highlights the importance of identifying intumescent cataracts as well as a combination of techniques to relieve intracapsular pressures needed to prevent AFS. However, some instances of anterior capsular tears are unavoidable. Therefore, focus will also be placed on techniques during cataract extraction used to manage anterior capsular tears, mitigating extension to the posterior capsule.

Application of Femtosecond Laser in Challenging Cataract Cases

Femtosecond laser can provide precise and customized incision of ocular tissue with excellent accuracy and predictability. Thus, femtosecond laser-assisted cataract surgery (FLACS) can theoretically enhance the safety and efficacy of cataract surgery by providing reproducible and reliable clear corneal incision, limbal relaxing incision, anterior capsulotomy, and lens fragmentation. However, thus far, the superiority of the anatomical and visual outcomes of FLACS over those of conventional cataract surgery have been unclear. Nevertheless, studies have indicated that FLACS can potentially be helpful in improving the safety of cataract surgery in challenging situations, such as zonular weakness, preexisting capsular tear, white cataract, shallow anterior chamber, and pediatric cataracts, which may contribute to enhanced visual and anatomical outcomes. In this review, we provide a summary of the application of femtosecond laser in general cataract cases. In addition, we introduce the application of FLACS in the abovementioned challenging situations and discuss the results of studies regarding the safety and outcome of FLACS in these challenging cases.

Automated precision pulse capsulotomy vs manual capsulorhexis in white cataracts: reduction in procedural time and resource utilization

PURPOSE

To compare the utility of precision pulse capsulotomy (PPC) with manual capsulorhexis for capsulotomy in white cataracts.

SETTING

Hospital-based academic practice.

DESIGN

Retrospective analysis of surgical case records and surgical videos from a single surgeon.

METHODS

Cases involving intumescent and nonintumescent white cataracts were identified. Capsulotomy outcomes, surgical outcomes, procedural time, and resource utilization, as well as patient demographic and health data, were analyzed and subjected to statistical testing.

RESULTS

15 cases of white cataract (10 intumescent and 5 nonintumescent) performed using continuous curvilinear capsulorhexis (CCC) were compared with 20 cases (9 intumescent and 11 nonintumescent) performed using PPC. The cases covered a period of 14 months before and 30 months after surgeon adoption of PPC. There were no significant differences between the 2 groups in patient age, sex, ethnicity, ocular history, medical history, and medications. PPC resulted in complete capsulotomies without tags or tears and intracapsular intraocular lens implantation with 360-degree capsular overlap in all 20 cases. There was 1 CCC case resulting in the Argentinian flag sign. Compared with CCC, PPC white cataract cases also demonstrated significant advantages in capsulotomy time, reduced use of trypan blue and ophthalmic viscosurgical device, and less overall procedural time.

CONCLUSIONS

PPC is a safe and highly effective method to create consistent capsulotomies in both intumescent and nonintumescent white cataracts. The use of PPC provides benefits of significant reductions in capsulotomy time, overall procedural time, and resource utilization, resulting in a streamlined treatment of these complex cataract surgery cases.

FLACS vs conventional phacoemulsification by junior cataract surgeons: randomized trial

PURPOSE

To report intraoperative performance and postoperative outcomes of femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification (PE) in the hands of junior surgeons.

SETTING

Iladevi Cataract & IOL Research Centre, Ahmedabad, Gujarat, India.

DESIGN

Prospective single-masked randomized controlled trial.

METHODS

320 eyes (320 patients) undergoing cataract surgery for uneventful cataracts in the hands of junior surgeons were randomized to Group 1-FLACS or Group 2-PE. Intraoperatively, cumulative dissipated energy (CDE) and fluid used were compared. Postoperatively, the following were compared: central corneal thickness (CCT) on day 1, 1 week, and 1 month; corneal clarity (day 1 and 1 week); anterior chamber inflammation (day 1 and 1 week); change in endothelial cell density (ECD) at 6 months postoperatively; and corrected distance visual acuity (CDVA) at 1 week and 1 month postoperatively.

RESULTS

157 and 158 patients in groups 1 and 2 analysed. Intraoperatively, CDE (5.41 ± 2.73 vs 8.83 ± 4.28 in Groups 1 and 2, P = .0001) and fluid used (79.33 ± 33.46 vs 101.82 ± 32.23 mL in Groups 1 and 2, P < .0001) were significantly lesser in Group 1. CCT was significantly higher in Group 2 on day 1 (550.96 ± 33.64 vs 587.70 ± 55.76 μm in Groups 1 and 2, P < .0001) and at 1 week postoperatively (527.94 ± 30.78 vs 545.11 ± 35.17 μm in Groups 1 and 2, P = .001). 72% of eyes had clear corneas on day 1 in Group 1 compared with 39% in Group 2 ( P = .01). Anterior chamber inflammation and CDVA were comparable. Change in ECD was significantly lower (9.3%) in Group 1 vs 12.7% in Group 2, P < .0001.

CONCLUSIONS

FLACS showed lower intraoperative CDE, fluid usage, lesser increase in CCT, better early postoperative corneal clarity, and lesser change in ECD at 6 months postoperatively in the hands of junior surgeons during standard cataract surgery.

Evaluation of the Optical Aspects of the Ophthalmic Viscosurgical Device During Femtosecond Laser-Assisted Cataract Surgery

Purpose

In femtosecond laser-assisted cataract surgery (FLACS), capsulorhexis can be performed with an ophthalmic viscosurgical device (OVD) filled in the anterior chamber. We aimed to investigate changes in the laser properties in various optical aspects, such as focal shifting, reflection, and absorption associated with OVD.

Methods

Simulation was achieved by calculating the laser power attenuation due to reflection and spot size change using the Gullstrand eye model. Additionally, we calculated the absorption coefficient by measuring the laser power passing through the OVD with a laser meter and evaluated the effect of absorption by the OVD.

Results

In our simulation, power attenuation due to reflection was a maximum of 0.07%, and power attenuation was 0.08% even when considering the change according to the incident angle. Power attenuation due to the change of the spot size at the focus was 0.005%. Owing to the absorption of the OVD, a power increase of up to 13.5% was required for an anterior chamber depth of 3.0 mm to obtain the same effect as the aqueous humor.

Conclusions

The main reason for laser power attenuation associated with OVD was laser absorption through the OVD, and could also be caused by laser cavitation bubbles. To complete a safe capsulotomy during FLACS, the laser power should be increased appropriately, considering the absorption by the OVD in the anterior chamber.

Translational Relevance

The study results can be applied to calculate the optimal femtosecond laser energy to achieve complete capsulotomy during FLACS in the presence of anterior chamber OVD.

Safety of femtosecond laser-assisted cataract surgery versus conventional phacoemulsification for cataract: A meta-analysis and systematic review

Purpose

To compare the complications of femtosecond laser-assisted cataract surgery (FLACS) with those of conventional phacoemulsification surgery (CPS) for age-related cataracts.

Methods

PubMed, Cochrane Library, and EMBASE were systematically searched for studies comparing FLACS and CPS. Outcomes were operative complications, including the intraoperative capsule tear, postoperative corneal edema, macular edema, uncontrolled IOP, etc. The effect measures were weighted with odds ratios with 95% CIs.

Results

Nineteen RCTs and 18 cohort studies, including 24,806 eyes (11,375 of the FLACS group and 13,431 of the CPS group), were identified. There were no significant differences between the two groups in anterior capsule tear, corneal edema, macular edema, uncontrolled IOP, vitreous loss, posterior vitreous detachment, etc. Posterior capsule tear rate showed a significantly lower in RCT subgroups (P ​= ​0.04) and without differences in total (P ​= ​0.63). Significant differences were observed in the incidence of descemet membrane tear/trauma (P ​= ​0.02) and IFIS/iris trauma (P ​= ​0.04. Additionally, The FLACS specific complications showed a significantly higher rate of miosis (P ​< ​0.0001), corneal epithelial defect (P ​= ​0.001), corneal haze (P ​= ​0.002), and subconjunctival hemorrhage (P ​= ​0.01).

Conclusions

FLACS maintains the same safety compared with CPS in terms of all intraoperative and postoperative complications. Although FLACS did show a statistically significant difference for several FLACS specific complications, it would not influence the visual outcome and heal itself.

Adjusted femtosecond laser capsulotomy distance in white cataracts to decrease incomplete capsulotomy: a randomized comparative cohort study

BACKGROUND

To compare safety and effectiveness between standard position and adjusted distance pre- and post-anterior capsule of femtosecond laser capsulotomy in white cataracts surgery.

METHODS

Selected white cataracts that underwent LenSx femtosecond laser capsulotomy were randomized into groups A (standard position, with 300 µm symmetrically pre- and post-anterior capsule), B (increased distance with 400 µm symmetrically pre- and post-anterior capsule), and C (unsymmetrical distances of 200 µm pre- and 400 µm post-anterior capsule, respectively). All these surgeries were performed by the same experienced surgeon. Complications, including incomplete capsulotomy and capsule tears, were recorded. In addition, femtosecond capsulotomy and phacoemulsification parameters, IOLs centrality and corrected distance visual acuity were assessed.

RESULTS

A total of 113 eyes were included in this study. There were 8 (21.6%) incomplete capsulotomy and 1 anterior capsule tear in group A. Meanwhile, only 2 eyes (5.1%) had incomplete capsulotomy with none showing capsule tear in group B. In group C, only 1 eye (2.7%) had incomplete capsulotomy and no capsule tear occurred. Mean femtosecond laser capsulotomy time was longer in group B compared with groups A and C. Average cumulative dispersed energy, IOL centrality and corrected distance visual acuity were similar in all groups.

CONCLUSIONS

Appropriate adjustment on femtosecond laser capsulotomy distance by reducing pre-anterior capsule and increasing post-anterior distance, may decrease incomplete capsulotomy and be more effective in white cataracts surgery.

TRIAL REGISTRATION

Clinical trial registration number: ChiCTR2100043863.

Lens capsule-related complications in femtosecond laser-assisted cataract surgery: a study based on video analysis

PURPOSE

To analyse the occurrence and potential causes of lens capsule-related complications during femtosecond laser-assisted cataract surgery (FLACS).

METHODS

This prospective consecutive cohort study included the first 1600 eyes (from 1140 consecutive patients) who received FLACS performed by the same surgeon from May 2015 to December 2018. The potential causes and characteristic signs of capsulotomy-related complications, including incomplete capsulotomies and radial anterior capsule (AC) tears, were summarised based on the agreement of two ophthalmologists after they analysed the surgical videos. Subgroup analysis was conducted to characterise the capsulotomy learning curve.

RESULTS

Of the 1600 eyes, 52 (3.25%) had incomplete capsulotomies and 22 (1.38%) had radial AC tears. The most common causes of incomplete capsulotomies were eye tilt (16 eyes, 30.77%), air bubbles or ocular secretions at the interface (14 eyes, 26.92%) and white cataracts (7 eyes, 13.46%). Additionally, 54.55% (12/22) of AC tears were due to incomplete capsulotomy and secondary capsulorhexis. A significant difference was noted between the first 200 eyes and subsequent groups in terms of the incidence of incomplete capsulotomies. No difference was observed in the incidence of AC tears after the initial 100 procedures.

CONCLUSION

The most common causes of incomplete capsulotomies were eye tilt and air bubbles or ocular secretions at the interface. Secondary capsulorhexis after incomplete capsulotomy is the main risk factor for AC tears. There was a steep learning curve for laser capsulotomy in the first 100 operated eyes, as evidenced by the higher complication rate, but this stabilised after 200 procedures.

Recent developments in anterior capsulotomy for cataract surgery

PURPOSE OF REVIEW

Successful anterior capsulotomy is an important step in cataract surgery. This article reviews the various anterior capsulotomy techniques available to surgeons to optimize the step, including those that have become available since the introduction of femtosecond-laser-assisted cataract surgery (FLACS). Studies comparing the relative advantages of each technique will be emphasized.

RECENT FINDINGS

Manual continuous curvilinear capsulorhexis (CCC) and FLACS remain the two most widely studied techniques for achieving anterior capsulotomy. Each technique has been shown to be effective for a wide range of patients and cataract surgery complications. Meta-analyses have shown that FLACS provides similar results to manual CCC for long-term cataract surgery outcomes. Several alternative methods for anterior capsulotomy have been described, which aim to provide some of the advantages of laser capsulotomy at a lower cost; among these, precision pulse capsulotomy (PPC) and selective laser capsulotomy (SLC) have been investigated the most in the literature so far.

SUMMARY

Cataract surgeons have an increasing number of techniques for anterior capsulotomy available. Manual CCC and FLACS remain the most widely used, and most well studied. The latest techniques, PPC and SLC, have shown promise in the few studies performed since they were introduced.

Cataract: Advances in surgery and whether surgery remains the only treatment in future

Background

Cataract is the world's leading eye disease that causes blindness. The prevalence of cataract aged 40 years and older is approximately 11.8%-18.8%. Currently, surgery is the only way to treat cataracts.

Main Text

From early intracapsular cataract extraction to extracapsular cataract extraction, to current phacoemulsification cataract surgery, the incision ranges from 12 to 3 ​mm, and sometimes to even 1.8 ​mm or less, and the revolution in cataract surgery is ongoing. Cataract surgery has transformed from vision recovery to refractive surgery, leading to the era of refractive cataract surgery, and premium intraocular lenses (IOLs) such as toric IOLs, multifocal IOLs, and extended depth-of-focus IOLs are being increasingly used to meet the individual needs of patients. With its advantages of providing better visual acuity and causing fewer complications, phacoemulsification is currently the mainstream cataract surgery technique worldwide. However, patient expectations for the safety and accuracy of the operation are continually increasing. Femtosecond laser-assisted cataract surgery (FLACS) has entered the public's field of vision. FLACS is a combination of new laser technology and artificial intelligence to replace fine manual clear corneal incision, capsulorhexis, and nuclear pre-fragmentation, providing new alternative technologies for patients and ophthalmologists. As FLACS matures, it is being increasingly applied in complex cases; however, some think it is not cost-effective. Although more than 26 million cataract surgeries are performed each year, there is still a gap in the prevalence of cataracts, especially in developing countries. Although cataract surgery is a nearly ideal procedure and complications are manageable, both patients and doctors dream of using drugs to cure cataracts. Is surgery really the only way to treat cataracts in the future? It has been verified by animal experiments that lanosterol therapy in rabbits and dogs could make cataract severity alleviated and lens transparency partially recovered. Although there is still much to learn about cataract reversal, this groundbreaking work provided a new strategy for the prevention and treatment of cataracts.

Conclusions

Although cataract surgery is nearly ideal, it is still insufficient, we expect the prospects for cataract drugs to be bright.

Three-Dimensional Heads-up Cataract Surgery Using Femtosecond Laser: Efficiency, Efficacy, Safety, and Medical Education-A Randomized Clinical Trial

Purpose

To compare the efficiency, efficacy, and safety, as well as the educational value, of heads-up (three-dimensional visualization system–assisted) and traditional microscopic cataract surgery.

Methods

This randomized noninferiority trial enrolled 242 eyes of 201 patients who received femtosecond laser-assisted cataract surgery. The questionnaire study enrolled 26 medical interns and 39 medical students. Patients received surgery under either a three-dimensional visualization system (3D group, 117 eyes) or traditional microscope (TM group, 125 eyes) after random allocation. The primary outcome was surgical time. The noninferiority margin of surgical time was 60 seconds. Secondary outcomes included ultrasound power, phacoemulsification time, visual acuity, intraocular pressure, endothelial cell density, central corneal thickness, complications, and observer satisfaction scores for surgical procedures.

Results

Surgical time was 462.03 ± 80.36 seconds in the 3D group and 452.13 ± 76.63 seconds in the TM group (difference 9.90 seconds; 95% CI, –9.98 to 29.78; P = 0.365). Visual acuity and other perioperative parameters were comparable between the 3D group and the TM group (all P > 0.05). Incidences of both intraoperative and postoperative complications were low and not statistically different between groups (all P > 0.05). Across all observers, 3D surgery was superior to TM surgery for improving the degree of satisfaction (all P < 0.001).

Conclusions

The surgical efficiency of heads-up cataract surgery is not inferior to traditional microscopic surgery. Both methods achieved similar efficacy and safety outcomes. Moreover, heads-up cataract surgery showed a significant advantage in medical education.

Translational Relevance

Our findings show that heads-up cataract surgery has comparable efficiency, efficacy, and safety, as well as superior medical educational value, to TM surgery, which lays the foundation for promoting and popularizing this technology.

The Latest Evidence with Regards to Femtosecond Laser-Assisted Cataract Surgery and Its Use Post 2020

Femtosecond laser-assisted cataract surgery (FLACS) was introduced with the hope of making cataract surgery safer and making the refractive result more predictable. It is only in the last four years that level 1 prospective randomised controlled trials (RCT) using current technology have been published. These, along with a meta-analysis of recent studies have shown that there seems to be little long-term visual benefit when using FLACS with monofocal lenses. The promised decrease in ultrasound energy required to remove a cataract has not been consistently demonstrated. There is level one evidence that the rate of posterior capsular rupture is less with FLACS using modern software. The round capsulotomy may be of increasing importance with the uptake of toric, multifocal and extended depth of focus lenses where a predictable capsulotomy size and precise placement of the lens becomes more important.

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Parameters of Capsulorrhexis and Intraocular Lens Decentration After Femtosecond and Manual Capsulotomies in High Myopic Patients With Cataracts

Purpose: To compare the parameters of capsulorrhexis and intraocular lens decentration after femtosecond laser capsulotomy and manual continuous curvilinear capsulorrhexis in high myopic patients with cataracts. Methods: This is a prospective consecutive non-randomized comparative cohort study. Selected patients with axial length > 26.0 mm were divided into femtosecond laser capsulotomy (FS) group and manual continuous curvilinear capsulorrhexis (CCC) group. Five experienced phacoemulsification surgeons conducted all surgeries. Intraoperative complications and post-operative anterior segment photography were recorded. Intraocular lens decentration, area of capsulorrhexis, circularity, and capsule overlap were measured at 1 week, 1 month, and 2 years after surgery. Between group differences of parameters were determined with independent-sample t-test or the Mann-Whitney U-test, analysis of variance test, Pearson chi-square test, and Spearman rank correlation test. Results: The study included 142 eyes (108 patients), 68 eyes in the FS group, and 74 eyes in the CCC group. At 1 week, 1 month, and 2 years after surgery, the area of capsulorrhexis in the CCC group was significantly larger than in the FS group (P < 0.05), while no significant difference was noted in circularity values. The complete overlap ratio in the FS group was significantly higher than that in the CCC group (P < 0.05) at each measured timepoint. Significant correlations were noted between the anterior chamber depth and the area of capsulorrhexis in the CCC group (R = 0.25, P = 0.04), but did not correlate in the FS group (P > 0.05). In patients with an anterior chamber depth >3 mm, the capsule-intraocular lens (IOL) overlap of the CCC group was less than that of the FS group at all measured timepoints after surgery (P < 0.05). Meanwhile, the IOL decentration in the CCC group was significantly greater than that of the FS group in those patients at 2 years after surgery (P < 0.05). Conclusion: In high myopic patients with cataracts, with anterior chamber depth more than 3 mm, femtosecond laser capsulotomy can achieve better capsulorrhexis sizing and centering. Due to more precise capsulotomy and a better capsule-IOL overlap in the FS group, femtosecond laser capsulotomy resulted in better long-term centration of the IOL.

Clinical Results After Precision Pulse Capsulotomy

Purpose

To compare residual refractive error and complication rates between eyes undergoing a manual capsulotomy and those receiving a precision pulse capsulotomy using an automated device.

Patients and Methods

This study was a non-interventional two-arm retrospective chart review of clinical results after bilateral cataract surgery or refractive lens exchange (RLE) surgery with a monofocal toric intraocular lens (IOL) or a trifocal IOL where a manual capsulorhexis (Manual) or automated precision pulse capsulotomy (PPC) was performed.

Results

Exams from 243 eyes (122 PPC, 121 Manual) from 124 patients were reviewed; about 75% of which had a trifocal IOL implanted. There was no statistically significant difference in the MRSE with either IOL type, or overall. The overall percentage of eyes with residual refractive cylinder ≤ 0.50 D was significantly higher in the PPC group (89% vs. 79% in the manual group, p = 0.03), primarily driven by results with the toric IOL. Best corrected distance visual acuity was not statistically significantly different by group. Capsulotomy-related complications were lower in the PPC group relative to the manual group (4.1% vs. 6.6%), but this result was not statistically significant (p = 0.38).

Conclusion

Significantly more eyes had refractive cylinder ≤0.50 D in the PPC group. For all other measures, the automated PPC device produced clinical results equivalent to those achieved with a manual capsulorhexis.

Efficacy of Femtosecond Laser-Assisted Capsulotomy: Experimental Evaluation Using the Zonular Dehiscence Model

Purpose

The purpose of this study was to evaluate experimentally the efficacy of femtosecond laser (FL)-assisted capsulotomy using an eye model with different degrees of zonular dehiscence (ZD).

Methods

An eye model with ZD was created by removing the total iris and including the planned range of the ZD in porcine and human cadaver eyes. FL-assisted capsulotomies (laser group) and manual capsulotomies (manual group) were created for the eye model with 0, 45, 135, 180, and 270 degrees of ZD. The continuity, mean diameter, ellipticity, and decentration of the capsulotomy were evaluated using the captured images. The same evaluation of FL-assisted capsulotomies was done for five human cadaver eyes with 180 degrees of ZD.

Results

In the laser group, no differences were seen in the mean diameter, ellipticity, and decentration, although the manual group resulted in significantly larger, ovalized, and decentered capsulotomies with different degrees of ZD (P < 0.001, P < 0.001, and P = 0.0317, respectively). Continuous capsulotomies or capsulotomies with microadhesions were obtained up to 180 degrees of ZD, and incomplete treatment areas were seen in eyes with 270 degrees of ZD. Capsulotomy of the human cadaver eyes with 180 degrees of ZD showed similar results to those of porcine eyes.

Conclusions

In this experimental study, FL-assisted capsulotomy showed favorable results in eyes with between 0 and 180 degrees of ZD compared to conventional manual capsulotomy.

Translational Relevance

Our experimental model can simulate the capsulotomy in cases with ZD, the results are useful when determining the indication for FL-assisted capsulotomies.

FLACS in Congenital Iris Coloboma: A Useful Technique

This paper reports the technique and outcome of femtosecond laser-assisted cataract surgery (FLACS) in an iris coloboma patient (59-year-old male patient) with bilateral grade 3 cataractous lens and a shallow anterior chamber. Best-corrected visual acuity (BCVA) was 0 on logMAR with spherical equivalent (SE) 9 D in the right eye, and BCVA of 0.3 logMAR with a SE 8.75 D in the left. FLACS was performed on the left then the right eye using the Catalys platform of Johnson & Johnson (intraocular lens implantation of AMO Tecnis 1 ZCB00). Customized parameters were constructed to create capsulotomies of 4.54.7 mm for the left and right eyes, respectively, with manual centration of the distorted pupils. On the second day of follow-up, left-eye BCVA was 0.5 with SE 1 D, and right-eye BCVA was 1 with SE −0.75 D. At the 1-year follow-up, eyes showed stable bilateral Tecnis 1 IOL and refraction. FLACS is a safe surgical option with stable outcomes in cases of cataract with iris coloboma.

[Current value of femtosecond laser-assisted cataract surgery]

After more than 10 years of experience with the femtosecond laser in cataract surgery, it can be concluded that the safety profile of femtosecond laser-assisted cataract surgery (FLACS) is comparable to that of conventional cataract surgery. This technique offers the possibility to perform incisions with a precision superior to that of any surgeon in the world, based on the connection of preoperative and intraoperative diagnostics. This results in new possibilities to revolutionize the surgical procedure of cataract surgery and to generate new therapeutic approaches for the treatment of cataracts. The combination of keratotomy for correcting astigmatism, intraocular lenses supported by capsulotomy and individually adapted fragmentation patterns is already a component of a personalized cataract surgery.

Clinical and Surgical Outcomes of Femtosecond Laser-Assisted Cataract Surgery (FLACS) on Hard Cataracts in the Egyptian Population

Objective

To evaluate the clinical and surgical outcomes of femtosecond laser-assisted cataract surgery (FLACS) in hard cataract of Egyptian population.

Setting

ICare Center, Alexandria, Egypt.

Design

Retrospective observational.

Methods

The study included 50 FLACS cases of 40 patients who had cataract; NO4 NC4 or more according to Lens Opacities Classification System III (LOCS III), performed between October 2018 and May 2019. The cases underwent anterior capsulotomy, lens fragmentation, and corneal incisions with the femtosecond laser. Arcuate keratotomy was performed in selected cases. Phacoemulsification and implantation of an intraocular lens are then performed.

Results

Patients mean age was 63.06 ± 7.75 yr, mean femtosecond laser energy was 12.92 ± 0.72 mJ, mean docking time was 3.00 ± 0.83 min and overall mean laser treatment time was 92.00 ± 25.01 sec. Mean laser treatment time was lower in cases that did not get astigmatic keratectomy (87.7 ± 18.97 vs 89.47 ± 13.43 sec; p < 0.73). Attempted refraction was -0.09 ± 0.52 D and achieved 12 months postoperative manifest sphere equivalent refraction (SER) was -0.19 ± 1.11 D (r = 0.8 and P˂0.001). Mean error (ME) was -0.2 ± 1.11 (range: -2.5-1.5) while mean absolute error (MAE) was 0.97 ± 0.57 (range: 0-2.5). Eighty percent and 92% of cases had 1 month postoperative SER within 1.0 D and 1.5 D, respectively. One eye (2%) had incomplete capsulotomy, 7 eyes (14%) had incomplete corneal incision and lens fragmentation was complete in all cases except 1 eye (2%). Thirty-four eyes (68%) showed postdocking conjunctival ecchymosis and 35 eyes (70%) had intraoperative miosis.

Conclusion

FLACS has low complication rate with effective results. High cost of technology is still the main barrier against its popularity.

The benefits and drawbacks of femtosecond laser-assisted cataract surgery

INTRODUCTION

Since the introduction, femtosecond laser-assisted cataract surgery was believed to revolutionize cataract surgery. However, the judgment of clinical benefit was found to be far more complex than initially might have been thought. The aim of this review was to analyze the benefits and drawbacks of femtosecond laser-assisted cataract surgery compared with traditional phacoemulsification cataract surgery.

METHODS

PubMed and the Web of Science were used to search the medical literature. The following keywords were searched in various combinations: femtosecond laser, femtosecond laser-assisted cataract surgery, phacoemulsification cataract surgery, FLACS.

RESULTS

The benefits of femtosecond laser-assisted cataract surgery include lower cumulated phacoemulsification time and endothelial cell loss, perfect centration of the capsulotomy, and opportunity to perform precise femtosecond-assisted arcuate keratotomy incisions. The major disadvantages of femtosecond laser-assisted cataract surgery are high cost of the laser and the disposables for surgery, femtosecond laser-assisted cataract surgery-specific intraoperative capsular complications, as well as the risk of intraoperative miosis and the learning curve.

CONCLUSION

Femtosecond laser-assisted cataract surgery seems to be beneficial in some groups of patients, that is, with low baseline endothelial cell count, or those planning to receive multifocal intraocular lens. Nevertheless, having considered that the advantages of femtosecond laser-assisted cataract surgery might not be clear in every routine case, it cannot be considered as cost-effective.

Femtosecond laser assisted cataract surgery in a cataract patient with a "0 vaulted" ICL: a case report

BACKGROUND

Femtosecond laser assisted cataract surgery (FLACS) combined with implantable collamer lenses (ICLs) extraction has been shown to be a feasible method for patients developing cataracts after the ICL implantation. All reported cases had shallow vaults, ranging from 47 μm (μm) to 100 μm. We report for the first time, a case in which the FLACS was performed on the "0" vault eye.

CASE PRESENTATION

A 38-year-old man with anterior subcapsular cataracts underwent the FLACS combined with ICLs extraction 6 years after ICLs implantation in both eyes. In his left eye, the ICL touched the anterior capsule, existing "0" vault. During the capsulotomy, cavitation bubbles were trapped in the shallow space beneath the ICL, developing from small bubbles into big ones, which resulted in the incomplete capsulotomy. Comparatively, in the right eye, the ICL vault was measured 72 μm, and the capsulotomy was complete and no big cavitation bubbles formed. In both eyes, capsulotomy zones were manually assigned to the anterior capsule surface in the process of laser identification. However, the nuclear pre-fragmentations were unsuccessful in both eyes. Other steps of surgeries were performed uneventfully. Depending on the design of monovision, the uncorrected distance visual acuity (UDVA) was 20/32, and the near uncorrected visual acuity (UCVA) was 20/25 in both eyes postoperatively.

CONCLUSIONS

This case suggested that the surgeon should pay attention to the incomplete laser capsulotomy when using a femtosecond laser in cataractous cases with "0" vaulted ICLs, and manual adjustment was required in the process of laser identification.

The Clinical Relationship of Anterior Capsular Tears and Vertical Spacing in the Femtosecond Laser Capsulotomy Procedure

PURPOSE

To evaluate the frequency of anterior capsule tears and capsule edge irregularities in femtosecond laser anterior capsulotomy, including the effect of optimized vertical spacing settings.

METHODS

Three thousand eight hundred thirty-four cases were examined and grouped according to the femtosecond laser capsulotomy settings using manufacturer default settings with a vertical spacing of 10, 15, and 20 µm. Capsulotomy edge irregularities and anterior capsule tears were recorded intraoperatively.

RESULTS

The anterior capsule tear rates for the 10, 15, and 20 µm groups were 0.79%, 0.35%, and 0.09%, respectively. The capsule edge irregularity rates for the 10, 15, and 20 µm groups were 6.25%, 1.13%, and 1.15%, respectively. The treatment times for the 10, 15, and 20 µm groups were 1.6, 0.7, and 0.8 second, respectively. The risk reduction of anterior capsule tears positively correlated with the 15 and 20 µm group settings. The anterior capsule tear rate difference between the 10 and 20 µm group settings was statistically significant. Capsule edge irregularity rates were reduced in the 15 and 20 µm group settings. Eye movement was monitored in the 20 µm group and was observed in 9 of 13 patients with capsule edge irregularities.

CONCLUSIONS

Anterior capsule tear rates are low with femtosecond laser cataract surgery. The rate can be further reduced with optimization of the settings, including an increase in vertical spacing. [J Refract Surg. 2019;35(5):280-284.].