Comparing corneal outcome between femtosecond laser-assisted cataract surgery and conventional phaco surgery in Fuchs' endothelial dystrophy patients: a randomized pilot study with 6mo follow up

The outcomes of postoperative eye patching after cataract surgery in patients with Fuchs' endothelial corneal dystrophy

PURPOSE

To investigate the influence of post-operative eye patching on corneal thickness, endothelial cells' loss and visual acuity in patients diagnosed Fuchs' endothelial corneal dystrophy (FECD).

SETTING

Public healthcare centre, Shamir Medical Centre, Israel.

METHODS

This randomized controlled trial included patients with FECD undergoing routine cataract surgery in a public medical centre. Patients were randomly assigned to 2 groups: the eye undergoing surgery was covered with a patch for 24 h in the first group (patched group), and a plastic shield was used in the second (non-patched group). Both groups received a unique dose of a local steroid and antibiotic post-operatively. The eyes were examined pre-operatively, and on days 1, 7 and 30 post-surgery . Examination included: best corrected visual acuity (BCVA), comeplete slit lamp examination, intra ocular pressure (IOP), anterior chamber depth (ACD), central corneal thickness (CCT) using the IOL Master 700 (Zeiss, Germany) and endothelial cell density (ECD) using Specular microscopy. Cumulative dissipated energy (CDE) and operation time were recorded for all cases.

RESULTS

The study included 46 eyes of 46 patients diagnosed with FECD. Twenty-three eyes in the patched group, and 23 eyes in the non-patched group . Thirty days post-operatively the CCT in the patched group decreased by 60 ± 38 mµ (9%) compared to 92 ± 80 mµ (13.5%) in the non- patched group (p = 0.04). Seven days post-operatively the CCT in the patched group decreased by 31 ± 35 mµ (5%) compared to 58 ± 76 (8%) in the non-patched group, but this difference did not reach statistical significance (p = 0.081). There was no statistically significant difference in endothelial cells loss as well as BCVA at 1, 7 and 30 days post-operatively between the study groups.

CONCLUSIONS

Avoiding eye patch post-operatively after cataract surgery in patients with FECD results in better corneal clarity recovery and reduced corneal edema one month post-operatively. Visual acuity and endothelial cell's loss were not influenced by patching.

Laser-assisted cataract surgery versus standard ultrasound phacoemulsification cataract surgery

BACKGROUND

Cataract is the leading cause of blindness in the world and, as such, cataract surgery is one of the most commonly performed operations globally. Surgical techniques have changed dramatically over the past half century with associated improvements in outcomes and safety. Femtosecond lasers can be used to perform the key steps in cataract surgery, such as corneal incisions, lens capsulotomy and fragmentation. The potential advantage of femtosecond laser-assisted cataract surgery (FLACS) is greater precision and reproducibility of these steps compared to manual techniques. The disadvantages are the costs associated with FLACS technology.

OBJECTIVES

To compare the effectiveness and safety of FLACS with standard ultrasound phacoemulsification cataract surgery (PCS) by gathering evidence from randomised controlled trials (RCTs).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; which contains the Cochrane Eyes and Vision Trials Register; 2022, Issue 5); Ovid MEDLINE; Ovid Embase; LILACS; the ISRCTN registry; ClinicalTrials.gov; the WHO ICTRP and the US Food and Drug Administration (FDA) website. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 10 May 2022.

SELECTION CRITERIA

We included RCTs where FLACS was compared to PCS.

DATA COLLECTION AND ANALYSIS

Three review authors independently screened the search results, assessed risk of bias and extracted data using the standard methodological procedures expected by Cochrane. The primary outcome for this review was intraoperative complications in the operated eye, namely anterior capsule, and posterior capsule tears. The secondary outcomes included corrected distance visual acuity (CDVA), quality of vision (as measured by any validated patient-reported outcome measure (PROM)), postoperative cystoid macular oedema complications, endothelial cell loss and cost-effectiveness. We assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 42 RCTs conducted in Europe, North America, South America and Asia, which enrolled a total of 7298 eyes of 5831 adult participants. Overall, the studies were at unclear or high risk of bias. In 16 studies the authors reported financial links with the manufacturer of the laser platform evaluated in their studies. Thirteen of the studies were within-person (paired-eye) studies with one eye allocated to one procedure and the other eye allocated to the other procedure. These studies were reported ignoring the paired nature of the data. There was low-certainty evidence of little or no difference in the odds of developing anterior capsular tears when comparing FLACS and PCS (Peto odds ratio (OR) 0.83, 95% confidence interval (CI) 0.40 to 1.72; 5835 eyes, 27 studies) There was one fewer anterior capsule tear per 1000 operations in the FLACS group compared with the PCS group (95% CI 4 fewer to 3 more).  There was low-certainty evidence of lower odds of developing posterior capsular tears with FLACS compared to PCS (Peto OR 0.50, 95% CI 0.25 to 1.00; 5767 eyes, 26 studies). There were four fewer posterior capsule tears per 1000 operations in the FLACS group compared with the PCS group (95% CI 6 fewer to same).  There was moderate-certainty evidence of a very small advantage for the FLACS arm with regard to CDVA at six months or more follow-up, (mean difference (MD) -0.01 logMAR, 95% CI -0.02 to 0.00; 1323 eyes, 7 studies). This difference is equivalent to 1 logMAR letter between groups and is not thought to be clinically important. From the three studies (1205 participants) reporting a variety of PROMs (Cat-PROMS, EQ-5D, EQ-SD-3L, Catquest9-SF and patient survey) up to three months following surgery, there was moderate-certainty evidence of little or no difference in the various parameters between the two treatment arms. There was low-certainty evidence of little or no difference in the odds of developing cystoid macular oedema when comparing FLACS and PCS (Peto OR 0.84, 95% CI 0.56 to 1.28; 4441 eyes, 18 studies). There were three fewer cystoid macular oedema cases per 1000 operations in the FLACS group compared with the PCS group (95% CI 10 fewer to 6 more).  In one study the incremental cost-effectiveness ratio (ICER) (cost difference divided by quality-adjusted life year (QALY) difference) was GBP £167,620 when comparing FLACS to PCS. In another study, the ICER was EUR €10,703 saved per additional patient who had treatment success with PCS compared to FLACS. Duration ranged from three minutes in favour of FLACS to eight minutes in favour of PCS (I2 = 100%, 11 studies) (low-certainty evidence).  There was low-certainty evidence of little or no important difference in endothelial cell loss when comparing FLACS with PCS (MD 12 cells per mm2 in favour of FLACS, 95% CI -40 to 64; 1512 eyes, 10 studies).  AUTHORS' CONCLUSIONS: This review of 42 studies provides evidence that there is probably little or no difference between FLACS and PCS in terms of intraoperative and postoperative complications, postoperative visual acuity and quality of life. Evidence from two studies suggests that FLACS may be the less cost-effective option. Many of the included studies only investigated very specific outcome measures such as effective phacoemulsification time, endothelial cell count change or aqueous flare, rather than those directly related to patient outcomes. Standardised reporting of complications and visual and refractive outcomes for cataract surgery would facilitate future synthesis, and guidance on this has been recently published.

Comparison of femtosecond laser-assisted cataract surgery and conventional phacoemulsification on corneal impact: A meta-analysis and systematic review

This meta-analysis aims to compare corneal injuries and function after femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification surgery (CPS). A comprehensive literature search of PubMed, EMBASE, and the Cochrane Controlled Trials Register was conducted to identify randomized controlled trials (RCT) and high-quality prospective comparative cohort studies comparing FLACS with CPS. Endothelial cell loss percentage (ECL%), central corneal thickness (CCT), endothelial cell density (ECD), endothelial cell loss (ECL), percentage of the hexagonal cell (6A), and coefficient of variance (CoV) were used as an indicator of corneal injury and function. Totally 42 trials (23 RCTs and 19 prospective cohort studies), including 3916 eyes, underwent FLACS, and a total of 3736 eyes underwent CPS. ECL% is significantly lower in the FLACS group at 1-3 days (P = 0.005), 1 week (P = 0.004), 1 month (P<0.0001), 3 months (P = 0.001), and 6 months (P = 0.004) after surgery compared to CPS. ECD and ECL appeared no statistically significant difference between the two groups, except for the significant reduction of ECD at 3 months in the CPS group (P = 0.002). CCT was significantly lower in the FLACS group at 1 week (P = 0.05) and 1 month (P = 0.002) early postoperatively. While at 1-3 days (P = 0.50), 3 months (P = 0.18), and 6 months (P = 0.11), there was no difference between the FLACS group and the CPS group. No significant difference was found in the percentage of hexagonal cells and the coefficient of variance. FLACS, compared with CPS, reduces corneal injury in the early postoperative period. Corneal edema recovered faster in the FLACS group in the early postoperative period. In addition, FLACS may be a better option for patients with corneal dysfunction.

Corneal densitometry: an innovative method to quantitatively evaluate corneal changes after phacovitrectomy

BACKGROUND

To quantitatively investigate corneal changes and the correlation between corneal densitometry (CD) and endothelial parameters after phacovitrectomy.

METHODS

Thirty-eight eyes with idiopathic full-thickness macular holes (iFTMHs) and cataracts underwent phacovitrectomy. Examinations were conducted at baseline and Day 1, Day 7, Month 1, and Month 3 postoperatively. CD and central corneal thickness (CCT) were measured using Pentacam. Corneal endothelial cell density (ECD), coefficient of variation (CV), and hexagonality (HEX) were measured using specular microscopy.

RESULTS

ECD and HEX significantly decreased after surgery and the change in HEX occurred prior to CV. CCT increased immediately after surgery and recovered 3 months postoperatively. CD values increased significantly 1 day after surgery and then gradually decreased. For CD in the 0-2 mm zone, it took 1 month to recover in the central and posterior layers and 3 months in the anterior and total layers. For CD in the 2-6 mm zone, the central layer recovered at Day 7, the anterior and total layers recovered at 1 month, and the posterior layer did not recover until 3 months postoperatively. The CD within all layers in the 0-2 mm zone was positively correlated with CCT. Posterior CD in the 0-2 mm zone was negatively correlated with ECD and HEX.

CONCLUSIONS

CD is not only correlated with CCT, ECD, and HEX but also reflects the state of the whole cornea and each layer. CD can be an objective, rapid, and noninvasive tool that reflects corneal health and undetectable edema and monitors the process of lesion repair.

TRIAL REGISTRATION

This study was registered with the Chinese Clinical Trial Registry (31/10/2021, ChiCTR2100052554).

Kataraktoperation beim Vorliegen einer Fuchs-Endotheldystrophie

Bei Betroffenen mit einer Fuchs-Endotheldystrophie beginnen die Probleme mit den Augen häufig in einem Alter, in dem sich auch schon erste Anzeichen einer Katarakt zeigen. Und umgekehrt findet man in der augenärztlichen Praxis immer wieder Patient*innen mit einer deutlichen Katarakt und einer Cornea guttata als Nebenbefund. In beiden Situationen stellt sich dann die Frage, ob zunächst nur eine posteriore lamelläre Keratoplastik (in Deutschland meist als DMEK) bzw. nur eine Kataraktoperation erfolgen oder ob gleich ein kombiniertes Vorgehen (sog. Triple-Operation) angestrebt werden sollte. Nur bei jungen Betroffenen mit einer fortgeschrittenen Fuchs-Endotheldystrophie ohne jeglichen Hinweis auf eine Katarakt und gut erhaltener Akkommodation kann, je nach individuellen Gegebenheiten, eine alleinige DMEK sinnvoll sein, in allen anderen Fällen erscheint eine Triple-Operation geeigneter. Dabei erscheint ein sequenzielles Vorgehen in diesen Situationen weniger angebracht, da sich in zahlreichen Studien zeigte, dass der Verlauf und die Ergebnisse nach einer Triple-Operation mit denen nach einem sequenziellen Vorgehen vergleichbar sind. Beim Vorliegen einer signifikanten Katarakt und einer Cornea guttata fällt die Entscheidung im Hinblick auf das operative Vorgehen deutlich schwerer. Hierbei gibt es unterschiedliche Aspekte in der Anamnese sowie den ophthalmologischen Untersuchungen (z. B. zentrale Hornhautdicke, Endothelzelldichte), die einem bei der Entscheidung helfen können. Soll dann zunächst nur eine Kataraktoperation erfolgen, sollten geeignete Maßnahmen ergriffen werden, um ein möglichst optimales Ergebnis trotz Vorliegen der Cornea guttata zu erreichen. Im folgenden Beitrag soll auf die wichtigsten prä-, peri- und postoperativen Aspekte im Hinblick auf die bestmögliche operative Versorgung von Betroffenen mit Fuchs-Endotheldystrophie und Katarakt eingegangen werden.

Cataract surgery and intraocular lens placement in patients with Fuchs corneal dystrophy: a review of the current literature

PURPOSE OF REVIEW

Late-onset Fuchs endothelial corneal dystrophy (FECD) is seen in approximately 4% of individuals over the age of 40. With the growing population of adults over the age of 65, ophthalmologists need to be aware of the preoperative, perioperative, and postoperative considerations involved in cataract surgery in Fuchs patients.

RECENT FINDINGS

Management of cataract patients with FECD requires preoperative assessment of endothelial cell size, density, and morphology. Considerations for perioperative endothelial cell loss include patients with hyperopia and shallow anterior chambers, phacoemulsification technique, transfer of ultrasonic energy to the cornea, corneal-protective perioperative agents, as well as thermal and mechanical damage.

SUMMARY

Ophthalmologists performing cataract surgery on patients with FECD must carefully consider the risks of endothelial cell loss during surgery and minimize the risk of corneal decompensation after surgery. Preoperative management should evaluate the severity of the FECD as well as individual factors such as cataract density, the health and thickness of the cornea, and the anterior chamber depth. Perioperative techniques, adjustments to biometry calculations, and intraocular lens (IOL) selection may help optimize visual outcomes and recovery time.

Comparison of perioperative parameters in one-handed rotational phacoemulsification versus conventional phacoemulsification and femtosecond laser-assisted cataract surgery

AIM

To compare perioperative parameters of one-handed rotational phacoemulsification technique (one-handed phaco-roll) with each of other two techniques, "Divide et Conquer" and femtosecond laser-assisted cataract surgery (FLACS).

METHODS

In this retrospective and comparative cohort study, eyes with uncomplicated cataract (nuclear density grade 2 to 3) treated routinely with one-handed phaco-roll (n=23; Group 1) or "Divide et Conquer" (n=23; Group 2) or FLACS (n=23; Group 3) were enrolled. Intraoperative parameters including effective phaco-time (EPt), ultrasound time (USt), aspiration time, surgical time, phacoemulsification (phaco)-power, balanced salt solution (BSS) use, cumulative dissipated energy (CDE) were recorded and compared. Clinical outcomes including best corrected visual acuity (BCVA), corneal endothelial cell density (ECD), endothelial cell loss (ECL), central corneal thickness (CCT) and central macular thickness (CMT), were assessed and compared pre-operatively and at 1mo after surgery.

RESULTS

Aspiration and surgical time, and BSS used were lower in Group 1 (P<0.01) than other groups. EPt, phaco-power and CDE were lower in Group 1 (P<0.05) than Group 2 but not significantly different from Group 3. In Group 1, USt was lower (P<0.05) than Group 2 but higher (P<0.05) than Group 3. BCVA improved in all groups without significant difference between Group 1 and the other ones. No significant differences regarding all post-operative morphologic outcomes (ECD, ECL, CCT, CMT) were reported. No clinical complications occurred.

CONCLUSION

One-handed phaco-roll seems to be less time-consuming than "Divide et Conquer" and FLACS and less energy-consuming than "Divide et Conquer". Furthermore, one-handed phaco-roll seems to have an equal safety profile compared to the other two techniques.