All laser cataract surgery compared to femtosecond laser phacoemulsification surgery: corneal trauma

Qualitative and quantitative endothelium changes after cataract surgery: ultrasound phacoemulsification vs. nanolaser technique

Purpose

The aim of this study was to evaluate corneal endothelial cell density and morphology, central corneal thickness, and best visual acuity using ultrasound (US) phacoemulsification or nanosecond laser technique.

Setting

Department of ophthalmology, Nabeul, Tunisia.

Design

Prospective cohort study.

Methods

This study included eyes with nuclear cataracts with a density grade of 1, 2, 3, or 4 according to LOCS III, divided into two groups; group 1 had conventional US, and group 2 had nanosecond laser. The endothelial cell density (ECD), coefficient of variation (CoV) in cell size, percentage of hexagonal cells, central corneal thickness (CCT) and best visual acuity (VA) were evaluated during 24 months.

Results

Seventy-four eyes had uneventful surgery, 40 in group 1, 34 in group 2. Three procedures in group 2 required conversion to standard phacoemulsification. The mean ECD decreased from 2616.4 ± 194.6 cells/mm2 in group 1 preoperatively to 2088.4 ± 229.9 after 2 years. In group 2, it decreased from 2611.8 ± 186.5 cells/mm2 to 2276.4 ± 163.8 after 2 years. The change was statistically significant in both groups. The decline of the mean ECD in group 2 was significantly less important than in group 1 (p = <10-2). The mean percentage of hexagonal cells was 45.18 ± 4.9 preoperatively and 43.5% ± 6.6 after 2 years in group 1. In group 2, it remained almost stable with 45.6 ± 5.1 and 45.4% ± 6.6 preoperatively and after 2 years, respectively. Preoperatively, the mean CoV was 0.39 ± 0.037 in group 1 and 0.38 ± 0.04 in group 2. After 2 years, it was 0.38 ± 0.04 and 0.37 ± 0.038 in group 1 and group 2, respectively. The changes of the mean CoV and the mean percentage of hexagonal cells were significant in both groups, but the difference between the groups was significant only during the six first months postoperatively. In preoperative, the mean corneal central thickness was 509.7 ± 19.5 in group 1 and 510.3 ± 20.4 in group 2. In both groups, the mean corneal thickness increased on D1 postoperatively to 550.9 in group 1, and 528.2 in group 2. The mean corneal thickness decreased more rapidly after 1 week in group 2, to find the initial values. Visual acuity improved from 0.76 Log Mar ± 0.5 at enrolment to 0.45 Log Mar ± 0.2, and 0.033 Log Mar ± 0.086 in group 1 at 1 day post-operative and after 24 months, respectively and from 0.58 Log Mar ± 0.28 to 0.2 Log Mar ± 0.09 and 0.035 Log Mar ± 0.083, respectively in group 2. There was no significant difference in VA at each follow-up between groups except for day 1.

Conclusion

Our study showed lower corneal tissue trauma, and lower endothelial cell loss in the laser cataract surgery compared to phacoemulsification.Clinical trial registration: (https://classic.clinicaltrials.gov/ct2/show/NCT05886283), identifier NCT05886283.

Cataract Surgery-Indications, Techniques, and Intraocular Lens Selection

BACKGROUND

Opacification of the lens of the eye (cataract) is usually due to aging. It is a painless, progressive condition that affects contrast and color perception and alters refraction, leading to visual loss that may be total. In cataract surgery, the turbid lens is replaced by an artificial lens. An estimated 600 000 to 800 000 such procedures are performed in Germany each year.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed, including meta-analyses, Cochrane reviews, and randomized controlled clinical trials (RCTs).

RESULTS

Cataract is the most common reversible cause of blindness around the world (approximately 95 million people). The surgical replacement of a turbid lens with an artificial lens is usually carried out under local anesthesia. The standard technique for fragmentation of the nucleus of the lens is ultrasonic phacoemulsification. RCTs have not shown the superiority of the femtosecond laser over phacoemulsification for this purpose so far. The spectrum of artificial intraocular lenses, aside from the conventional type with a single focus, include lenses with multiple foci, extended-depth-of-focus (EDOF) lenses, and astigmatism-correcting lenses.

CONCLUSION

In Germany, cataract surgery is usually performed on an outpatient basis under local anesthesia. Artificial lenses with various additional functions are available nowadays; the choice of lens depends on the needs of the individual patient. Patients must be adequately informed about the advantages and disadvantages of the different lens systems.

Femtosecond Laser-Assisted Cataract Surgery in Soft and Hard Nuclear Cataracts: A Comparison of Effective Phacoemulsification Time

Purpose

To compare effective phacoemulsification time (EFX) in femtosecond laser-assisted cataract surgery (FLACS) versus traditional quick chop phacoemulsification (QCP) in senile nuclear cataracts with different densities focusing on soft and hard ones.

Patients and Methods

A prospective non-randomized comparative study was carried out in Al Watany Eye Hospital and Ain Shams University Hospital, Cairo, Egypt; 250 eyes with senile nuclear cataract (NC) were included and classified into two main groups, FLACS and QCP groups. Each of them was stratified according to nuclear density into three subgroups, subgroups I (Soft NC), II (Medium NC), and III (Hard NC). Sextans-softened fragmentation pattern was performed in the FLACS group. Total EFX utilized for nucleus disassembly and removal was recorded by the completion of each surgery.

Results

A total of 117 eyes were included in the FLACS group and 133 eyes in the QCP group. No significant difference in EFX was observed between the two groups (P = 0.228). Regarding subgroups, EFX showed no statistically significant difference between FLACS and QCP (P = 0.283) in soft NC. For hard NC, a trend to lower values of EFX in FLACS compared with QCP was found, but without statistically significant difference (P = 0.122). Only in medium NC were significantly lower values obtained in FLACS compared with QCP (P < 0.0001).

Conclusion

When compared with QCP technique, FLACS can be used for advantages aside from EFX reduction, including astigmatic keratotomies, accurate sizing, and centration of capsulotomies especially in hard and soft nuclear cataracts. Significant reduction of total EFX with FLACS is most prominent only in medium-density nuclear cataracts.

[What will cataract surgery look like in the future? Alternatives in the pipeline]

Phacoemulsification is the most frequently performed surgery in the world. Over the past few years, this surgery seems to have reached a plateau with no further innovative breakthroughs. In this paper, we focus on alternatives techniques, the latest innovations, and the research and development pipeline in this field.

Cataract surgery and lens implantation

PURPOSE OF REVIEW

This review aims to introduce recent updates in cataract surgery and lens implantation.

RECENT FINDINGS

Compared to phacoemulsification, femtosecond laser-assisted cataract surgery (FLACS) may offer benefit for cataract patients with other complicated ocular diseases, such as corneal disease and vitreous abnormalities. Meanwhile, several types of novel intraocular lenses (IOLs) have been introduced to the market, and each of them has particular features in improving patients' visual acuity. In addition, based on a series of studies, multifocal IOL is superior to monofocal IOL when it comes to providing a better visual correction at different distances. Furthermore, a research group has introduced a new approach for cataract surgery - all laser surgery (FLACS band with nanolaser emulsification), which can effectively reduce iatrogenic trauma to the cornea. Also, a novel technique designed for children can lessen damage from cataract surgery.

SUMMARY

Based on previous studies, we summarize the new proceedings in FLACS and the indications for applying multifocal or toric IOL. In addition, we briefly introduce a new approach to cataract surgery - all laser surgery (FLACS band with nanolaser emulsification), and a less invasive surgical procedure used in pediatric cataract patients.

Outcomes study between femtosecond laser-assisted cataract surgery and conventional phacoemulsification surgery using an active fluidics system

Purpose

The purpose of this study was to compare intraoperative parameters between femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification using Centurion^® Vision System with Active Fluidics.

Setting

This study was performed at Brasília Ophthalmologic Hospital, Brasília, Federal District, Brazil.

Patients and methods

This was a prospective randomized comparative study. Patients with the diagnosis of cataract and surgical extraction programmed were divided into two groups: conventional phacoemulsification and FLACS. Intraoperative data were collected and submitted for statistical analysis.

Results

A total of 400 eyes were enrolled, 200 in each group. There were no surgical complications. Groups were statistically equivalent in age and nucleus density. Cumulative dissipated energy and torsional time were significantly reduced in the FLACS group. Conventional surgery had less fluid usage, total case time and aspiration (ASP) time.

Conclusion

FLACS with Active Fluidics System can reduce the ultrasound energy use during cataract surgery, in spite of increasing case time, fluid usage and ASP time.