Femtosecond Laser-Assisted Cataract Surgery

Efficiency of venturi vs peristaltic-based phacoemulsification in femtosecond laser cataract surgery

PURPOSE

To compare the efficiency of peristaltic vs venturi vacuum platforms when applied to femtosecond-treated cataract.

SETTING

Outpatient Eye Center, Mercy Health System, Springfield, Missouri.

DESIGN

This is a prospective randomized controlled trial of 111 patients with moderate nuclear sclerosis scheduled for bilateral routine laser cataract surgery (LCS) ( ClinicalTrials.gov ; NCT03970525).

METHODS

Patients were randomized to receive surgery in 1 eye with a peristaltic system and the other with a venturi system. The vacuum and phacoemulsification power were the same for both systems. The primary outcomes were phacoemulsification energy (EFX), ultrasound time (UST), phacoemulsification in/out time (PIOT), surgery time (speculum in/out time), and endothelial cell count (ECC).

RESULTS

The type of vacuum/phacoemulsification system used during LCS had a significant impact on the 4 procedural outcomes. Specifically, EFX, UST, PIOT, and total microscope time (speculum in/out case time) were lower when the venturi system was used compared with the peristaltic system ( t (100) = -4.28, P < .001). The vacuum system used did not affect the uncorrected distance visual acuity, corrected distance visual acuity, or central cornea thickness. ECC decreased by 6.38% with venturi and 8.32% with peristaltic ( t (87) = 1.19, P = .235). There were no complications.

CONCLUSIONS

Venturi-based phacoemulsification was more efficient than peristaltic, based on energy and time, when used for removal of femtosecond-treated cataract.

Comparison of venturi and peristaltic based phacoemulsification efficiency in routine femtosecond laser cataract surgery

OBJECTIVE

To compare the efficiency of venturi and peristaltic pump phacoemulsification systems in patients undergoing routine laser cataract surgery.

DESIGN

Single center, nonrandomized clinical study.

PARTICIPANTS

The study compared consecutive eyes with moderate nuclear sclerosis undergoing routine laser cataract surgery at the Outpatient Eye Center, Mercy Health System, Springfield, MO, USA.

METHODS

Each surgery used the same femtosecond laser settings. Surgeries were performed with either a venturi or peristaltic vacuum system by a single surgeon (WJS). The EFX, percent power, ultrasound time (UST), the total time that the phaco tip was in the eye (phaco tip in/out time, PIOT), and the surgery time (speculum in/out time) were recorded. Exclusions and intraoperative complications were also analyzed.

RESULTS

995 eyes were included in the study. The EFX in the venturi eyes (1.7 ± 1.3; n = 521) compared to peristaltic eyes (2.1 ± 1.4; n = 474) was lower (p < 0.0001). Similarly, the UST in the eyes performed with the venturi system versus the peristaltic system was reduced (32.4 ± 22.3 s vs 40.7± 25.7 s; p < 0.0001). The PIOT in the venturi group compared to the peristaltic group was less (71.1 ± 31.1 sec vs 79.1 ± 36.1 s; p = 0.0002). The case time (speculum in/out time) was lower for the venturi eyes (307.2 ± 68.8 s vs. 311.6 ± 53.6 s; p = 0.268).

CONCLUSION

In eyes undergoing routine laser cataract surgery, the use of the venturi pump system was more efficient compared to the peristaltic pump system based on energy use and time, and there was no significant difference in complications.

Femtosecond laser versus manual clear corneal incision in implantable collamer lens surgery

This study aims to compare the efficacy and safety of femtosecond laser-assisted implantable collamer lens (ICL) implantation with traditional manual ICL techniques. A retrospective analysis was conducted on patients who underwent ICL implantation at Beijing New Vision Eye Hospital in 2023. Patients (aged 18-45) were matched for gender and refractive error, with forty-two eyes in each group. Preoperative and postoperative parameters were measured at intervals of 1 day, 1 week, 1 month, 3 months, and 6 months post-surgery. Statistical analyses were conducted to compare outcomes between the two groups. Contrary to our expectations, short-term results (within 1 month) for the femtosecond laser-assisted group showed significantly lower visual acuity and higher astigmatism levels compared to the traditional group. Over time, both techniques yielded comparable outcomes in visual acuity and other parameters by 3 and 6 months postoperatively. The predictive accuracy for refraction outcomes remained superior in the traditional ICL group throughout the study period. The femtosecond laser-assisted ICL implantation did not display any significant short-term and long-term advantages over traditional manual ICL implantation methods. Given the increased costs and lack of clear benefits, femtosecond laser-assisted incisions are not recommended for ICL implantation at this time.

Incidence and analysis of intraoperative complications in femtosecond laser-assisted cataract surgery: a large-scale cohort study to establish the learning curve

AIMS

To assess the safety of femtosecond laser-assisted cataract surgery (FLACS) based on surgical parameters and intraoperative complications analysis and to determine the length of the learning curve for FLACS.

METHODS

A prospective consecutive cohort study was conducted on Chinese patients who underwent either FLACS (3289 cases) or contemporaneous conventional phacoemulsification cataract surgery (2130 cases). The laser group was divided into four subgroups in chronological order. We recorded intraoperative complication incidences and compared with surgical parameters between groups. Subgroup analysis was conducted to explore the learning curve of FLACS.

RESULTS

The laser group had a 4.93% incidence of incomplete capsulotomies and a 1.22% incidence of anterior capsule tears. Subgroup analysis showed significant differences in 8 aspects between the first 250 cases (50 cases per surgeon) and the last 2539 cases, but only 2 aspects differed between the second 250 cases (50 cases per surgeon) and the last 2539 cases. There were no significant differences between the third 250 cases (50 cases per surgeon) and the last 2539 cases.

CONCLUSIONS

The intraoperative complications of FLACS were reported, and the learning curve is associated with a significant reduction in the incidence of intraoperative complications. The length of the basic learning curve of FLACS is 100 cases, and the length of the advanced learning curve was 150 cases. This study demonstrated that FLACS is characterised by a relatively straightforward and secure operative technique.

Changes in cataract and refractive surgery practice patterns among JSCRS members over the past 20 years

PURPOSE

To evaluate changes in cataract and refractive surgery practice patterns among members of the Japanese Society of Cataract and Refractive Surgery (JSCRS) over the past 20 years.

STUDY DESIGN

Questionnaire survey study.

SUBJECTS AND METHODS

Clinical surveys were conducted annually between February and April from 2004 to 2023. Survey questions covered various areas, including cataract surgical techniques, anesthesia, endophthalmitis prophylaxis, toric and presbyopia-correcting intraocular lenses (IOLs), complications, and refractive surgery.

RESULTS

The highest (n=554 [36.8%]) and lowest (n=316 [19.1%]) numbers of responses were collected in 2012 and 2016, respectively. In perioperative management, the intraoperative use of polyvinyl alcohol-iodine solution and topical antibiotic prescription 3 days before surgery has increased. The use of intracameral injection at the end of surgery has also significantly increased, although it has not been established as common practice. In anesthesia, there is a clear polarization between the use of topical drops and tenon injection. The use of toric IOLs and presbyopia-correcting IOLs has significantly increased from 2010 to 2023. In the latter, the use of trifocal IOLs has particularly increased. Regarding IOL power calculations, the Barrett True K and the Barrett Universal II formulas are rapidly gaining popularity for application with and without post-laser vision correction, respectively. In refractive surgery, phakic IOLs and corneal refractive therapy have attracted considerable interest, followed by laser in situ keratomileusis.

CONCLUSIONS

Evaluation of annual clinical survey data over the past two decades provided valuable insights into the shifting practice patterns and clinical opinions among JSCRS members.

Economic evaluations in cataract surgery: a narrative review

Economic evaluations are tools for assessing emerging technologies and a complement for decision-making in healthcare systems. However, this topic may not be familiar for doctors and academics, who may be confused when interpreting the results of studies using these tools. Cataract is a disease which has received special attention in healthcare systems due to its high incidence, the great impact that it could have on patients' quality of life, and the fact that it can be definitively solved in almost all cases through cataract surgery. Historically, economic evaluations in cataract surgery have been conducted for many purposes by simply assessing whether the surgery is cost-effective for specific questions related to the implantation of multifocal intraocular lenses, surgical techniques, optimizing assessments, preventing diseases or complications, etc. Moreover, although there are systematic reviews about cataract surgery and narrative reviews introducing the concept of economic evaluations, as far as we know, no previous study has been conducted that synthesizes and integrates evidence coming from both fields. Thus, the purpose of this narrative review is to introduce doctors and academics to economic evaluation tools, to describe how these have been historically applied to cataract surgery, and to provide special considerations for the correct interpretation of economic studies.

Surgical time and efficacy of illuminated chopper-assisted cataract surgery involving miosis after femtosecond laser pretreatment

PURPOSE

To evaluate the efficacy of the illuminated chopper-assisted cataract surgery in terms of shortening the surgical time in eyes with miosis after femtosecond laser pretreatment.

METHODS

As retrospective study, three hundred thirty-six eyes of 336 consecutive patients who underwent the femtosecond laser and illuminated chopper-assisted cataract surgery were included. Cases with pupil less than 6 mm after femtosecond laser pretreatment were included in the miosis group. Pupil diameter, surgical time, and improved efficacy (100/surgical time×pupil size) were compared between eyes with and without miosis.

RESULTS

Of 336 eyes, 20 were included in the miosis group (6.0%). Pupil diameter was smaller in eyes with miosis than in those without miosis (5.23 ± 0.38 mm vs 7.35 ± 0.64 mm, p < 0.001); however, surgical time was not different (6.86 ± 0.73 min vs 6.60 ± 1.27 min, p = 0.071) between the two groups. Mechanical pupil dilations were not needed in any cases. As a result, improved efficacy was calculated to be higher in patients with miosis (2.83 vs 2.14, p < 0.001).

CONCLUSION

In terms of surgical time and improved efficacy, using the illuminated chopper simplified cataract surgery involving miosis after femtosecond laser pretreatment. The use of an illuminated chopper is expected to be a good solution for femtosecond laser-assisted cataract surgeries.

Update on Femtosecond Laser-Assisted Cataract Surgery: A Review

The advent of femtosecond lasers has resulted in a new standard in cataract surgery, intended to overmatch the paradigm of conventional phacoemulsification. Femtosecond laser-assisted cataract surgery (FLACS) enables a higher level of reproducibility, precision, accuracy, and customization when performing several steps of cataract (or lens) surgery. Capsulotomy, corneal incisions, lens fragmentation, and arcuate incisions are the main procedures performed using FLACS. As the demand for better refractive outcomes and spectacle independence increases, the features of FLACS are highly relevant, especially when considering the implantation of premium intraocular lenses, such as toric, enhanced depth-of-focus, or multifocal lenses. The present article reviews the state of the art of femtosecond laser-assisted cataract (lens) surgery, contemplating the advantages and limitations of the two types of femtosecond laser pulses available (high and low energy) by evaluating their reported outcomes and complications.

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.

Endothelial Cell Loss Following Cataract Surgery Using Continuous Curvilinear Capsulorhexis or Precision Pulse Capsulotomy

Purpose

To compare endothelial cell density (ECD), percentage of hexagonal cells (%Hex) and coefficient of variation (CV) in cell size following lens cataract surgery with phacoemulsification performed using Continuous Curvilinear Capsulorhexis (CCC) or Precision Pulse Capsulotomy (PPC).

Patients and Methods

Sixty-seven subjects were randomly assigned to undergo lens cataract removal with the capsulotomy step performed using either CCC or PPC. Specular microscopy images were obtained pre-operatively, 1 month and 3 months after surgery. ECD, %Hex and CV were analyzed in a masked fashion by an independent reading center.

Results

The mean percentage ECD loss at 1 month was 11.5% in the CCC group and 12.3% in the PPC group (P = 0.818; t-test). At 3 months, the mean percentage ECD loss was 11.7% in the CCC group and 12.4% in the PPC group (P = 0.815; t-test). The mean %Hex at 1 month was 54.3% in the CCC group and 54.7% in the PPC group (P = 0.695; t-test). At 3 months, the mean %Hex was 56.2% in the CCC group and 54.7% in the PPC group (P = 0.278; t-test). The CV at 1 month was 34.4% in the CCC group and 34.3% in the PPC group (P = 0.927; t-test). At 3 months, the CV was 32.7% in the CCC group and 33.4% in the PPC group (P = 0.864; t-test).

Conclusion

No differences in ECD loss, %Hex and CV were observed between patients who received CCC or PPC. PPC use during cataract surgery does not result in any increased endothelial cell loss beyond that normally associated with this surgery.

Femtosecond laser-assisted cataract surgery: Update and perspectives

Cataract surgery is among the most frequently performed surgical procedures worldwide and has a tremendous impact on patients' quality of life. Phacoemulsification (PCS) is accepted as a standard of care; its technique has continuously evolved and already achieved good anatomical, visual, and refractive outcomes. Lasers in ophthalmology are widely used in clinical practice, femtosecond lasers (FSLs) for corneal surgery in particular. It was natural to assess the usefulness of FSL in cataract surgery as this technology was within reach. Indeed, precise and reproducible cuttings provided by FSL platforms could improve standardization of care and limit the risk associated with the human element in surgery and provide a step toward robot-assisted surgery. After docking and planning the procedure, femtosecond lasers are used to perform corneal incisions, capsulorhexis, lens fragmentation, and arcuate incisions in an automated manner. A well-constructed corneal incision is primordial as it offers safety during the procedure, self-seals afterward, and influences the refractive outcome. Capsulorhexis size, centration, and resistance to shearing influence the surgery, intraocular lens (IOL) centration and stability, and posterior capsular opacification formation. Lens fragmentation is where most of the energy is delivered into the eye, and its amount influences endothelial cell damage and potential damage to other ocular structures. The arcuate incisions offer an additional opportunity to influence postoperative astigmatism. Femtosecond laser-assisted cataract surgery (FLACS) has been a topic of research in many studies and clinical trials that attempted to assess its potential benefits and cost-effectiveness over PCS and is the subject of this mini-review.