Femtosecond Laser-assisted Cataract Surgery Research Articles

A brief note on Femtosecond laser-assisted cataract surgery

Femtosecond Laser-Assisted Cataract Surgery (FLACS) is an advanced modality for cataract surgery. Its advantage in cataract surgery in terms of reduction of ultrasound power is controversial. We believe this controversy is due to different techniques and different nuclear densities included in the studies. Our study evaluated the Effective Phacoemulsification Time (EPT) during phacoemulsification with or without Femtosecond laser technology in different nuclear densities. The study comprised two main groups: Conventional phacoemulsification and FLACS groups. We stratified all eyes included in the study into soft and hard cataracts, and we employed the vertical quick chop technique for nucleus disassembly in all cases. In the FLACS group, we used sextans in addition to 350 microns grid softening

Intra- and early postoperative complications after standard cataract surgery or femtosecond laser-assisted cataract surgery combined with pars plana vitrectomy in cases of retinal diseases

Intra- and early postoperative complications after standard cataract surgery or femtosecond laser-assisted cataract surgery combined with pars plana vitrectomy in cases of retinal diseases

Zonulysis during Femtosecond Laser-Assisted Cataract Surgery

Zonulysis during Femtosecond Laser-Assisted Cataract Surgery

Clinical outcomes after femtosecond laser assisted cataract surgery with implantation of the TECNIS Symfony intraocular lens

AIM: To evaluate the clinical outcomes in terms of vision across distances (near, intermediate, and far), contrast sensitivity and subjective patient satisfaction after femtosecond laser-assisted cataract surgery (FLACS) with implantation of an extended range of vision (ERV) intraocular lens (IOL). METHODS: Forty patients (55 eyes) undergoing bilateral or monocular FLACS with implantation of the ERV IOL TECNIS Symfony (Johnson & Johnson Vision) were enrolled. Uncorrected distance (UDVA), intermediate (UIVA) and near visual acuities (UNVA) were evaluated at 3mo after surgery, as well the defocus curve, contrast sensitivity, patient satisfaction and spectacle independence. RESULTS: No severe complications occurred. All eyes showed a central position of the IOL in the capsular bag without tilting at 3mo after surgery. 3mo postoperative mean logMAR visual acuity at 5 m, 67 cm and 40 cm were -0.04 ±0.08, -0.17±0.22, 0.37±0.17, respectively. All patients obtained satisfactory UDVA and UIVA, as well as functional UNVA, meeting the needs of daily life. Spectacle independence rate was 94.55%. Contrast sensitivity results did not differ from those obtained with monofocal aspheric lenses. Likewise, no moderate and severe photic phenomena were reported. Mean patient satisfaction scores with distance, intermediate and near vision were 9.0, 9.0, and 7.0, respectively. CONCLUSION: FLACS with implantation of the ERV IOL TECNIS Symfony provides a successful visual restoration at far, intermediate distance and a functional-range near vision acuity, with minimal level of disturbing photic phenomena, and high rates of spectacle independence and patient satisfaction.

Recent Updates in Femtosecond Laser-assisted Cataract Surgery.

International Ophthalmology Clinics: Winter 2021 - Volume 61 - Issue 1 - p 77-94 doi: 10.1097/IIO.0000000000000338

Queratotomía arcuata transepitelial o intraestromal con láser de femtosegundo para corrección de astigmatismo corneal en el momento de la cirugía de cataratas

PurposeThe aim of this study was to compare the results of intrastromal arcuate incisions (AIs) and transepithelial AIs to treat corneal astigmatism during femtosecond laser-assisted cataract surgery (FLACS). MethodsThis retrospective study included 20 patients with corneal astigmatism between 0.70 and 2.00 diopters (D) who underwent FLACS with concurrent intrastromal AIs in one eye and transepithelial AIs in the fellow eye. The main outcomes measures at 2-3months of follow-up were the difference between preoperative and postoperative keratometric corneal cylinder (Kcyl), the correction index (CI) and the percentage of overcorrection. ResultsThe mean difference between preoperative and postoperative Kcyl revealed a mean value of 0.36±0.37D in the transepithelial group and 0.53±0.42D in the intrastromal group (P<.001). The mean CI was 0.83±0.71 in the transepithelial group and 0.68±0.29 in intrastromal group (P=.17). Five eyes (25%) had an astigmatism overcorrection in the transepithelial group and 1eye (5%) in the intrastromal group. ConclusionsBoth intrastromal and transepithelial AIs showed potential for mild to moderate astigmatism correction and appeared to be a safe procedure. Despite transepithelial AIs presented a higher CI, the intrastromal AIs results were more predictable.

Femtosecond Laser-Assisted Cataract Surgery: Does It Improve Outcomes in Fuchs Endothelial Corneal Dystrophy?

The role of femtosecond laser -assisted cataract surgery in patients with Fuchs endothelial corneal dystrophy remains poorly defined. This invited commentary examines the current evidence surrounding this often-debated topic.

Herpes simplex virus stromal keratitis and endotheliitis after femtosecond laser–assisted cataract surgery and astigmatic keratotomy

Two weeks after uneventful femtosecond laser–assisted cataract surgery (FLACS) with laser astigmatic keratotomy (AK) in the right eye, a 72-year-old woman developed a corneal ulcer and infiltrate in the superonasal AK incision, with severe anterior chamber reaction. She was initially treated for bacterial followed by fungal keratitis, without resolution. She was referred to our university corneal service for consultation. Based on clinical presentation and slitlamp examination, the patient was diagnosed with herpes simplex virus keratitis (HSK). The patient was administered topical steroid eyedrops and systemic antiviral therapy, with full resolution of the keratitis. To the authors’ knowledge, this is the first reported case of herpes simplex virus stromal keratitis and endotheliitis after FLACS combined with AK. This report postulates about possible etiologic factors for activation of HSK after femtosecond laser treatment and proposes preventative actions.

Evaluation of femtosecond laser-assisted anterior capsulotomy in the presence of ophthalmic viscoelastic devices (OVDs)

The introduction of femtosecond laser-assisted cataract surgery is an alternative approach to conventional cataract surgery. Our study aimed to determine the effectiveness of femtosecond laser-assisted capsulotomy in the presence of different ophthalmic viscoelastic devices (OVDs) in the anterior chamber. Fresh porcine eyes (n = 96) underwent LDV Z8-assisted anterior capsulotomy, either in the presence of an OVD (Viscoat, Provisc, Healon, Healon GV or HPMC) or without, using 90% and 150% energies respectively. Following that, the capsule circularity, tag’s arc-length, tag-length, tag-area and rupture strength (mN) of the residual capsular bag were evaluated. We found that increasing energy from 90 to 150% across the OVD sub-groups improved the studied capsulotomy parameters. Amongst the 90% energy sub-groups, the circularity and tag-parameters were worse with Viscoat and Healon GV, which have higher refractive index and viscosity compared to the aqueous humour. Using 150% energy, Healon GV showed a significantly worse total arc-length (p = 0.01), total tag-length (p = 0.03) and total tag-area (p = 0.05) compared to the control group. We concluded that; an OVD with a refractive index similar to aqueous humour and lower viscosity, such as Healon or Provisc, as well as a higher energy setting, are recommended, to enhance the efficacy of laser capsulotomy.

Comparison of Femtosecond Laser-Assisted Cataract Surgery and Conventional Phacoemulsification in Shallow Anterior Chambers and Glaucoma.

Purpose To compare femtosecond laser-assisted cataract surgery (FLACS) versus conventional phacoemulsification in shallow anterior chamber cataract patients with glaucoma or zonulysis. Methods This was a single-center retrospective review of cataract surgeries in shallow anterior chamber and glaucoma patients between January 2016 and December 2018 in which a LenSx femtosecond laser was used. The outcome measures included pre- and postoperative uncorrected and corrected distance visual acuity (UDVA and CDVA), intraocular pressure (IOP), endothelial cell density (ECD), endothelial cell loss (ECL), and object scatter index (OSI). Results One hundred and six eyes of 106 patients with a mean anterior chamber depth of 1.54 ± 0.51 mm were included in this study. Among them, 26 (23.2%) had zonulysis and 18 eyes had capsular tension ring implantation in general. The percentage of capsular tension ring implantation was statistically significantly lower in the FLACS group (P = 0.027). The UDVA, CDVA, ECD, and IOP were not statistically significant between the two groups at all time points. The postoperative ECL and OSI of the FLACS group was better than those of the conventional group (P < 0.01). Conclusions FLACS can reduce ECL and improve visual quality compared to the conventional phacoemulsification in shallow anterior chamber patients. Also, it has the trend of reducing the use of capsular tension rings in subluxated cataracts. It is an ideal choice for patients with complicated cataract such as with shallow anterior chambers, glaucoma, and zonulysis.

Changes in Corneal Endothelial Cells Morphology Due to Different Cataract Surgery Procedures: A Retrospective Study From November 2014 to November 2016

Introduction: The corneal endothelium is made up of an extremely thin layer of non -regenerating cells essential in keeping the cornea clear. The purpose of this study was to quantify the corneal endothelial cells morphology, visual acuity (VA) and refractive error in patients having femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification surgery (CPS). Methods: Clinical data from 56 eyes were included in this study. 28 eyes had FLACS surgery and another 28 eyes had CPS. Distance VA, refractive error, corneal thickness and endothelial cells morphology were evaluated pre-operatively and at 1 month follow up. Refractive error was determined subjectively and VA was taken using Snellen chart. Specular microscope was used to measure endothelial cells morphology and central corneal thickness. Mann Whitney test and Spearman correlation analysis were used to analyse the results. Results: There were no statistically significant difference in the mean endothelial cell density (p=0.24), mean central corneal thickness (p=0.68), mean coefficient of variance (p=0.19), mean hexagonality (p=0.44), VA (p=0.72) and postoperative refractive outcome (p=0.66) between both groups. The duration of surgery was noted to have no statistically significant difference between both groups (p=0.08), while the cumulative dissipated energy and torsional time showed a significant difference between groups (p=0.01 and p&lt;0.01 respectively). Conclusion: This study concluded that there was no significant difference in the endothelial cells morphology in patients undergoing both cataract surgeries. Both surgeries presented similar outcomes in the patients’ eyes.

Evaluation of femtosecond laser-assisted cataract surgery after 10 years of clinical application

Abstract Introduction Femtosecond laser-assisted cataract surgery (FLACS) has been considered a technological advance in modern cataract surgery. After years of experience, it has been observed that clinical outcomes had more complications than expected at the beginning. The aim of this study is to compare the benefits and disadvantages of the FLACS technique with conventional cataract surgery. Method The PubMed and Web of Science platforms were used to search for scientific literature. Results The femtosecond laser has currently improved the surgical technique in terms of the shorter ultrasound time used and the lower loss of endothelial cells. Likewise, the centration of capsulotomy and the correction of astigmatism with arcuate incisions have also been improved. As disadvantages, are the high cost of the laser, the intraoperative capsular complications, the induction of intraoperative myosis, and the learning curve of the technique. Conclusions The FLACS technique is considered beneficial for specific cases, such as patients with scheduled premium surgery, or with low endothelial cell count. However, it is believed that given the technological cost it is not a cost effective technique for most standard cases in our daily clinical practice.

FOCUSED (Femtosecond Optimized Continuous Uncorrected Sight with EDOF and Diffractive Multifocal IOLs) - A Review.

The aim of this article is to review techniques to maximize all-distance uncorrected visual acuity and minimize photic phenomena after the implantation of multifocal and extended-depth of focus (EDOF) intraocular lenses (IOLs). This review examines the role of femtosecond laser-assisted cataract surgery (FLACS) in postoperative minimization of astigmatism and optimization of outcomes with multifocal and EDOF lenses. By incorporating intraoperative and preoperative imaging, femtosecond platforms such as those that utilize iris or conjunctival vessel registration, can enable a precision of corneal incisions and toric IOL markings that enable the lowest possible postoperative levels of astigmatism. Current studies suggest that with increasing IOL complexity, that is, trifocal versus bifocal, image degradation with even low levels of postoperative astigmatism are increased. To this end, current data support the utility of femtosecond laser arcuate incisions to enable the achievement of 0.5 D or less postoperative astigmatism for best outcomes with multifocal lenses. The synergistic combination of multifocal/EDOF IOLs with FLACS is an extremely promising route in achieving postoperative spectacle independence for patients. The marriage of the precision of FLACS with the increasing complexity of multifocal/EDOF IOLs will fuel nomogram adjustment and systematic improvements, such as the Wörtz-Gupta formula. Such strategies provide an unprecedented precision to cataract surgery that makes FOCUSED (Femtosecond Optimized Continuous Uncorrected Sight with EDOF and Diffractive Multifocal IOLs) a reality.

Comparison of Nd:YAG Laser Capsulotomy Rates Between Refractive Segmented Multifocal and Multifocal Toric Intraocular Lenses

To investigate the early incidence of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy according to intraocular lens (IOL) type (nontoric vs toric) and surgical techniques (femtosecond laser-assisted cataract surgery vs conventional phacoemulsification) in eyes with refractive multifocal IOLs. Retrospective case-control study. Nine hundred thirteen eyes from 483 patients implanted with Lentis Mplus LS-313 MF20 (767 eyes) or Lentis Mplus Toric LU-313 MF20T (146 eyes) IOLs (Oculentis GmbH, Berlin, Germany) were enrolled. We compared the incidence of Nd:YAG laser capsulotomy between the nontoric and toric groups. In addition, the incidence of Nd:YAG laser capsulotomy was also evaluated according to the surgical technique used. The overall incidence of Nd:YAG laser capsulotomy was 10.2% (93/913 eyes). The Nd:YAG laser capsulotomy rate was significantly higher in the toric group (24/146; 16.4%) than in the nontoric group (69/767; 9.0%; P= .007). Of the 913 enrolled eyes, 448 eyes (49.1%) underwent femtosecond laser-assisted cataract surgery and 465 eyes (50.9%) underwent conventional phacoemulsification cataract surgery. There was no significant difference in the incidence of Nd:YAG laser capsulotomy between eyes with femtosecond laser-assisted cataract surgery and eyes with conventional phacoemulsification cataract surgery. Patients with refractive multifocal toric IOLs had higher early incidence rates of Nd:YAG laser capsulotomy when compared to those with refractive multifocal nontoric IOLs. Furthermore, femtosecond laser-assisted cataract surgery could not reduce the early incidence of Nd:YAG laser capsulotomy in this study.

The Effect on Post-Operative Intraocular Lens Centration by Manual Intraoperative Centration versus Auto-Centration.

IntroductionTo determine if intraoperative manual centration of the intraocular lens (IOL) during cataract surgery results in better early post-operative centration. It is common practice for cataract surgeons to align intraocular lens centration to the visual axis by manual intraoperative manipulation of the intraocular lens. We aim to compare post-operative intraocular lens centration between intraocular lenses that were allowed spontaneous positioning in the capsular bag and IOLs that were manually centred during implantation.Materials and MethodsOne hundred and twenty-five consecutive eyes that underwent either femtosecond laser-assisted cataract surgery (FLACS) or phacoemulsification and IOL (monofocal/toric/multifocal) implantation by a single surgeon were included. Post-operative IOL centration at 4 weeks was assessed and measured on a slit-lamp by a masked observer.ResultsA total of 17 (13.6%) IOLs were off-centered to some extent at 4 weeks post-operatively. All the decentered IOLs were graded as minimal or mild (<0.5mm) decentration. There was no statistically significant difference in the proportion of decentered IOLs between the manual centration group and non-centration group (p = 0.59).ConclusionThe final position of the IOL is not dependent on manual centration but rather on the design and symmetry of the IOL, as well as the integrity of the capsular bag.

Efficacy of 3D digital visualization in minimizing coaxial illumination and phototoxic potential in cataract surgery: pilot study.

To compare the coaxial light intensity required during cataract surgery and rate of postoperative visual recovery, with surgical visualization achieved with a traditional analog operating microscope compared with a 3D digital visualization system. Weill Cornell Medical Center, New York Presbyterian Hospital, New York, New York. Retrospective, consecutive, single-surgeon series. Patients undergoing femtosecond laser-assisted cataract surgery were retrospectively grouped into either: (1) visualization using the binoculars of a standard operating microscope (traditional group) or (2) visualization using a 3D digital visualization system affixed to the same operating microscope (digital group). Note was made in each case of light intensity used, light exposure time, intraoperative and/or postoperative complications, and postoperative visual acuities. The study comprised 24 eyes in the traditional group and 27 eyes in the digital group. There were no intraoperative or postoperative complications in either group and no difference in mean light exposure time, but the mean light intensity used in the digital group was significantly less (18.5% ± 1.5%) than that in the traditional group (43.3% ± 3.7%; P < .001). Furthermore, the digital group achieved a postoperative day 1 visual acuity that was within 2 lines of the postoperative month 1 visual acuity a greater percentage of time than that in the traditional group (81.5% of eyes vs 54.2% of eyes; P = .04). Light intensity was significantly decreased in patients who underwent cataract surgery assisted by the 3D digital visualization platform without an increase in complications or surgical time and possibly with a faster postoperative visual recovery.

Long-Term Evaluation of Capsulotomy Shape and Posterior Capsule Opacification after Low-Energy Bimanual Femtosecond Laser-Assisted Cataract Surgery.

Purpose To evaluate capsulotomy shape and posterior capsule opacification (PCO) during an 18-month follow-up for bimanual femtosecond laser-assisted cataract surgery (FLACS). Methods 74 eyes operated by a well-trained surgeon with bimanual FLACS technique using low-energy LDV Z8 (Ziemer Ophthalmic Systems AG, Port, Switzerland) were included in the study. The follow-up period was 18 ± 2 months. Another 91 eyes, which underwent standard bimanual microincision cataract surgery (B-MICS), served as a control group. In all cases, a BunnyLens AF (Hanita Lenses, Israel) intraocular lens was implanted in the bag. A digital image of the capsule with slit-lamp retroillumination was performed in all patients at 18 months of follow-up. Image analysis software (ImageJ) was used to evaluate the shape of the capsulotomy in terms of diameter, area, and circularity. PCO score was evaluated using EPCO 2000 software. Best corrected visual acuity (BCVA) and endothelial cell count (ECC) were evaluated before and after surgery at 1 and 18 ± 2 months. Results At 18 months, mean capsulotomy diameter was 5.34 ± 0.21 mm while capsulorhexis was 5.87 ± 0.37 mm (p < 0.001) and the deviation area from baseline was 1.13 ± 1.76 mm2 in FLACS and 2.67 ± 1.69 mm2 in B-MICS (p < 0.001). Capsulotomy circularity was 0.94 ± 0.04 while capsulorhexis was 0.83 ± 0.07 (p < 0.001). EPCO score was 0.050 ± 0.081 in the FLACS group and 0.122 ± 0.239 in the B-MICS group (p=0.03). The mean BCVA improvement was significant in both groups, without a significant difference at 18 months. We noticed a statistically significant difference in endothelial cell loss at 18 months (FLACS 12.4% and B-MICS 18.1%; p=0.017). Conclusions Bimanual FLACS is a safe and effective technique, as determined in a long-term follow-up. Capsulotomy shape presented higher stability and circularity in the FLACS group over the 18-month observation period. FLACS resulted in lower PCO scores and endothelial cell loss at 18 months in comparison to B-MICS standard technique.

Clinical Results of Femtosecond Laser-assisted Cataract Surgery in Eyes with Posterior Chamber Phakic Intraocular Lens

Clinical Results of Femtosecond Laser-assisted Cataract Surgery in Eyes with Posterior Chamber Phakic Intraocular Lens

Femtosecond laser-assisted cataract surgery in eyes with shallow anterior chamber depth: comparison with conventional phacoemulsification.

To compare the postoperative outcomes between femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification in eyes with shallow anterior chamber depth (ACD). Eye Clinic, NEUROFARBA Department, University of Florence, Italy. Prospective case series. Forty eyes of 40 patients with senile cataract and true ACD less than 2.00 mm underwent FLACS (femto group, n = 20) or manual phacoemulsification (phacoemulsification group, n = 20). Preoperatively and 1 week and 1 month and 6 months postoperatively, central corneal thickness (CCT) and endothelial cell density were evaluated; basal epithelial cell (BEC) and Langerhans dendritic cell (LDC) densities and keratocyte activation were assessed using in vivo corneal confocal microscopy. Intraoperative parameters such as cumulative dissipated energy (CDE) and ultrasound (US) power were recorded. Endothelial cell loss (ECL) was significantly lower in the femto group at all timepoints (P ≤ .001). In the phacoemulsification group, the CCT was significantly higher 1 week (P < .001) and 1 month (P < .001) postoperatively than preoperatively; conversely, in the femto group, it was higher only after 1 week (P < .001). BECs and LDCs significantly increased at 1 postoperative week (P < .001), returning to preoperative values after 1 month in both groups. Keratocyte activation remained significantly higher at 1 postoperative month only in the phacoemulsification group (P = .005). CDE and US power were lower in the femto group (P = .017 and P = .001, respectively); they were correlated with ECL (r = 0.662, P = .000; r = 0.389, P = .013). In eyes with shallow ACD, FLACS was a safe and an effective technique, significantly reducing the postoperative ECL and corneal inflammation compared with conventional phacoemulsification.

History of cataract surgery from ancient times to today

AbstractCataract surgery is the most frequently performed ophthalmic surgery worldwide. This year approximately 32 million surgeries will be performed. The journey to modern, quick, and safe cataract surgery has been quite long. This review covers topics from ancient couching to the most modern phacoemulsification and femtosecond laser-assisted cataract surgery. The gain in quality of life is the largest with cataract surgery compared to other implant surgeries (e.g. knee, hip replacement, etc.). Ophthalmology has made huge advancements in recent decades. New microsurgical tools and diagnostic equipment have been developed, together with new surgical methods and foldable intraocular lenses, made from biocompatible material. From monofocal lenses, through aspheric, toric, and multifocal lenses, to multifocal toric lenses, today almost all kinds of refractive error can be compensated, including presbyopia. Teamwork, precise preoperative assessment, and fine surgical technique should also be emphasized in order to achieve the best and most predictable postoperative results for both patient and surgeon.