Comparison of morphological and functional endothelial cell changes after cataract surgery: phacoemulsification versus manual small-incision cataract surgery

Safety of an Intracameral Fixed Combination for Mydriasis and Intraocular Anaesthesia During Cataract Surgery

Purpose

To compare the safety of a standardized, commercially available intracameral combination of mydriatics and anesthetic (ICMA) with a reference topical mydriatic regimen for cataract surgery.

Patients and Methods

The safety results from two international, randomized, controlled clinical studies were combined to compare ICMA at the beginning of cataract surgery (ICMA group) to the reference topical mydriatic regimen (reference group). Data were collected on ocular and systemic adverse events, corneal and anterior chamber examination, endothelial cell density, retinal thickness and visual acuity. Analysis was performed on a pooled safety set from both studies, preoperatively and up to 1 month postoperatively.

Results

342 patients received ICMA and 318 the reference topical regimen. Ocular adverse events were reported in 17.0% of patients in the ICMA group and 18.6% in the reference group. No difference was shown between groups in endothelial cell density (2208 ± 498 cells/mm2 for ICMA group versus 2241 ± 513 cells/mm2 for the reference group; p=0.547) and retinal thickness (change from baseline less than 50 µm in 94.7% versus 95.0% of patients, respectively) at 1 month postoperatively. At 1-day post-surgery, less patients in the ICMA group had moderate or severe (Grades 2 and 3) superficial punctate corneal staining (3.9% versus 7.0% for the reference group; p=0.064). Postoperatively, some ocular symptoms were also less frequently reported in the ICMA group. Best-corrected visual acuity increased in 96.0% of patients in the ICMA group and 95.8% in the reference group at 1 month.

Conclusion

ICMA injection at the beginning of cataract surgery was demonstrated to be safe and may also provide perioperative and postoperative advantages over the standard topical mydriatic regimen.

Effect of Nondominant Left-Handed Phacoemulsification Surgery on Corneal Endothelium

PURPOSE

To evaluate the effect of phacoemulsification surgery performed with the nondominant left hand on the corneal endothelium.

METHODS

The study included 160 patients who were followed up for at least six months after uneventful cataract surgery. Seventy-seven patients who underwent nondominant left-handed phacoemulsification were evaluated as Group 1 and 83 patients who underwent dominant right-handed phacoemulsification were evaluated as Group 2. In all the patients, preoperative axial length (AL), aqueous depth (AD), anterior chamber depth (ACD), and lens thickness (LT) were evaluated. All phacoemulsification procedures were undertaken with the same device by two surgeons using the same technique, and the intraoperative cumulative dissipated energy (CDE) value, effective phacoemulsification time, and total operative time were recorded. Corneal endothelial cell density (ECD), coefficient of variation (CV) percentage, hexagonal cell percentage (HCP), and central corneal thickness (CCT) measurements were evaluated by specular microscopy preoperatively and at the postoperative first and sixth months.

RESULTS

The two groups had a similar age and gender distribution and did not significantly differ in terms of the preoperative AL, AD, ACD, LT, intraoperative CDE, effective phacoemulsification time, and total operative time with similar age and gender distribution (p > 0.05 for all). The preoperative and postoperative first- and sixth-month specular microscopy measurements of ECD, CV, HCP, and CCT ​​were also similar in the groups (p > 0.05 for all).

CONCLUSIONS

In this study, it was observed that nondominant left-handed phacoemulsification resulted in similar changes in endothelial cell count and morphology to those obtained from dominant-handed phacoemulsification.

Comparison of changes in endothelial cell count and central corneal thickness after phacoemulsification and small-incision cataract surgery: A prospective observational study at a tertiary care center of eastern Uttar Pradesh

Purpose

Morphological stability and functional integrity of corneal endothelium are necessary to maintain long-term corneal transparency. When the number of endothelial cells drops below 450-800 cells/mm², corneal edema, irreversible loss of corneal transparency, and decreased vision occur. There is concern regarding manual small-incision cataract surgery (MSICS) being more harmful to the endothelium in comparison to phacoemulsification. Our study aims to determine which technique maintains the corneal parameters closest to the normal physiological state.

Methods

A prospective observational study was conducted over a period of 15 months on 100 eyes, out of which 43 patients underwent phacoemulsification surgery and 57 underwent MSICS. TOPCON SP-1P, Version 1.41, 50-60 Hz frequency, noncontact specular microscope with pachymeter was used to measure endothelial cell count (ECC) and central corneal thickness (CCT) on four occasions: 1 day prior to surgery and on day 1, 3^rd week, and 6^th week after surgery.

Results

In total, 100 eyes of 100 subjects were studied with no dropout during the study period. The age range was 40-70 years. There was no statistically significant difference between the preoperative mean ECC and mean CCT in phacoemulsification and SICS groups. A statistically significant difference was observed in the postoperative mean ECC (P < 0.01) and mean CCT (P < 0.001) on day 1 and 3^rd week between the phacoemulsification and SICS groups, respectively. The mean endothelial cell loss at 6 weeks was less with SICS but comparable with phacoemulsification.

Conclusion

SICS is significantly faster, less expensive, less technology dependent, can deal with all types of cataracts, is relatively safe, and is more appropriate for advanced cataracts.

Corneal endothelial protection during manual small-incision cataract surgery: A narrative review

Cataract causes bilateral blindness in 20 million people globally, the vast majority of whom live in developing countries. Manual small-incision cataract surgery (MSICS) has emerged as an efficient and economical alternative to phacoemulsification, giving comparable results in terms of final visual gain. One of the important determinants of postoperative visual gain is the status of the corneal endothelium. Multiple factors such as corneal distortion, irrigation solution turbulence, mechanical trauma by instruments, nuclear fragments, intraocular lens contact, and free oxygen radicals, all have been implicated in causing corneal damage during cataract surgery. MSICS with posterior chamber intraocular lens implantation has been reported to cause an endothelial cell loss of 15.83%, which is comparable with other modes of cataract surgery like extracapsular cataract extraction and phacoemulsification. Thorough preoperative assessment of endothelial status and taking necessary steps for endothelial protection during surgery can decrease the endothelial cell loss and overall burden of pseudophakic bullous keratopathy. In addition to surgical techniques, the type of irrigating solutions, ocular viscoelastic devices, intracameral dyes, and drugs all affect the endothelial cell status. This review presents a summary of available literature on the protection of endothelial cells during different steps of MSICS. This is especially relevant for developing countries where large-scale MSICS cataract surgeries are performed to decrease the cataract blindness burden.

Comparison of corneal endothelial cell loss during manual small-incision cataract surgery using viscoelastic-assisted nucleus removal versus continuous balanced salt solution plus technique - Randomized controlled trial

Purpose

The purpose of this study was to compare and analyze the endothelial cell loss during manual small-incision cataract surgery (MSICS) using the viscoelastic-assisted nucleus removal versus basal salt solution plus technique.

Methods

This was a prospective randomized trial of 204 patients who underwent MSICS using viscoelastic-assisted nucleus removal (Group 1- OVD) versus basal salt solution plus technique (Group 2- BSS) at a tertiary eye care hospital in North India from January 2018 to 2021. Of these 204 patients, 103 (50.5%) and 101 (49.5%) were allocated to Group 1 and 2, respectively. The parameters assessed were detailed history, demographics, and anterior and posterior segment details. Visual acuity, intraocular pressure (IOP), keratometry, pachymetry, and endothelial cell density were evaluated preoperatively and postoperatively on day 1 and 30.

Results

The mean age of the patients was 64.5 ± 8.2 years (range 48-82 years). There were 129 (63.2%) males and 75 (36.8%) females. The mean LogMAR visual acuity for both groups on day 1 (Group 1- 0.3 ± 0.1, Group 2- 0.5 ± 0.2) and day 30 (Group 1- 0.1 ± 0.2, Group 2- 0.1 ± 0.1) was statistically significant (P &lt; 0.001), and the mean IOP value showed a statistically significant value (P &lt; 0.009) on day 1 in Group 2 (15.0 ± 2.4 mmHg) and on day 30 (P &lt; 0.001) in both the groups (Group 1- 13.6 ± 1.8 mmHg, Group 2- 13.5 ± 2 mmHg). The horizontal and vertical k values also showed a statistically significant difference on day 1 and day 30 (P &lt; 0.001). The mean percentage change of central corneal thickness (CCT) in Group 1 was 17.7% and in Group 2 was 17.4% on day 1, and it was 1.1% on day 30 in both the groups, which was statistically significant (P &lt; 0.001) compared to preoperative values. The percentage change in endothelial cell density on day 1 was 9% in Group 1 and 4.6% in Group 2, which was statistically significant (P &lt; 0.001). On day 30, it was 9.7% and 4.8%, respectively, which was statistically significant (P &lt; 0.001).

Conclusion

Our study highlights statistically significant endothelial cell loss with viscoelastic-assisted nuclear delivery compared to BSS-assisted nuclear delivery during MSICS in a short follow-up of 1 month. The CCT values showed a slight increase, and the keratometry and IOP were unaffected compared to the preoperative parameters in both the groups.

Survey of Ophthalmology Training Experiences Among Young Ophthalmologists in the Asia-Pacific

PURPOSE

To describe ophthalmology training experiences across the Asia-Pacific (APAC).

DESIGN

Survey study.

METHODS

We utilized an anonymous online survey, which was previously validated and conducted in Europe, through Young Ophthalmologist leaders from the national member societies of the Asia-Pacific Academy of Ophthalmology (APAO) from September 2019 to July 2021. Responses were based on a 5-point Likert scale (where applicable) and data were analyzed using Microsoft Excel. Our main outcome measures were differences between regions, that is, Southeast Asia (SEA) and Western Pacific (WP); and seniority, that is, trainees/junior ophthalmologists and senior ophthalmologists.

RESULTS

We collated 130 responses representing 20 regions in the APAC region. The year of completion of ophthalmic training ranged from 1999 to 2024. The mean duration of training was 3.7±1.0 years. Most (98/130, 75%) indicated an interest for a common training standard across the APAC. Comparing SEA and WP trainees, both regions had similar working environments, but those in SEA reported significantly lower remuneration than their counterparts in WP ($600 vs $3000, P <0.05). WP trainees performed more phacoemulsification surgeries (76 WP vs 19 SEA), while SEA trainees conducted more manual small incision cataract surgeries (157 WP vs 1.5 SEA per duration of training). Senior ophthalmologists performed more cataract surgeries (210.9 senior ophthalmologists vs 40.1 junior ophthalmologists). Trainees had less confidence in medical competency areas such as interpreting an electroretinogram/visual evoked potential/electrooculogram (SEA=1.8, WP=2.1) and conducting an angiography (SEA=2.8, WP=3.4).

CONCLUSIONS

Our study highlighted heterogeneity among ophthalmology training experiences in the APAC region, with the majority indicating an interest in a common training standard.

Comparison of Corneal Tissue Profile of Pseudophakic and Phakic Donors

PURPOSE

To compare the endothelial quality of corneas obtained from pseudophakic donors with age-matched phakic controls.

METHODS

Retrospective analysis of 100 corneas each from pseudophakic and phakic eyes with donor age ≥60 years in both the groups was performed. The endothelial cell density, coefficient of variation, and percentage of hexagonal cells obtained by specular microscopy were compared between the two groups. The cut-off level of endothelial cell density (ECD) taken for optical keratoplasty was 2,000 cells/mm2.

RESULTS

The male and female donors constituted 60% (n=120) and 40% (n=80), respectively. The mean age of the donors was 66.9±7.3 years in the phakic group and 69.9±7.7 years in pseudophakic group. The mean ECD in the phakic group was 2757.6±328.5 cells/mm2 and that in the pseudophakic group was 2225.5±471.9 cells/mm2 (P<0.0001). The mean coefficient of variation in the phakic group was 37.1±5.0 and that in the pseudophakic group was 38.6±11.1 (P=0.234). The mean percentage of hexagonality in the phakic group and the pseudophakic group was 52.0±6.4% and 51.2±7.2%, respectively (P=0.414). Both in univariate and multivariate linear regression analysis, age of the donor was found to be negatively associated in predicting ECD (P=0.002 and P=0.003, respectively). Sixty-nine and thirty-three corneas from the phakic and pseudophakic donor pool were used respectively.

CONCLUSION

Difference in ECD between the phakic and the pseudophakic donor group was found to be statistically significant. The ECD in the pseudophakic group was found to be above the cut-off limit required for keratoplasty. Hence, pseudophakic corneas may also be used for transplantation.

Risk factors for fluctuations in corneal endothelial cell density (Review)

The cornea is a transparent, avascular and abundantly innervated tissue through which light rays are transmitted to the retina. The innermost layer of the cornea, also known as the endothelium, consists of a single layer of polygonal endothelial cells that serve an important role in preserving corneal transparency and hydration. The average corneal endothelial cell density (ECD) is the highest at birth (~3,000 cells/mm²), which then decrease to ~2,500 cells/mm² at adulthood. These endothelial cells have limited regenerative potential and the minimum (critical) ECD required to maintain the pumping function of the endothelium is 400-500 cells/mm². ECD < the critical value can result in decreased corneal transparency, development of corneal edema and reduced visual acuity. The condition of the corneal endothelium can be influenced by a number of factors, including systemic diseases, such as diabetes or atherosclerosis, eye diseases, such as uveitis or dry eye disease (DED) and therapeutic ophthalmological interventions. The aim of the present article is to review the impact of the most common systemic disorders (pseudoexfoliation syndrome, diabetes mellitus, cardiovascular disease), eye diseases (DED, uveitis, glaucoma, intraocular lens dislocation) and widely performed ophthalmic interventions (cataract surgery, intraocular pressure-lowering surgeries) on corneal ECD.

"Chopper Shield" Technique to Protect Corneal Endothelium During Phacoemulsification Surgery for Rock Hard Cataracts

Purpose

To describe an innovative technique of using a chopper as a shield for preventing mechanical corneal endothelial trauma that can occur during the phacoemulsification of brunescent cataracts.

Methods

This prospective study included patients with hard cataracts (grade nuclear opalescence 4 and above on LOCS III) who underwent phacoemulsification surgery. The chopper shield technique was performed in 48 eyes of 44 patients. The technique entailed placing the chopper horizontally as a shield anterior to the emulsifying nuclear fragment between the phaco tip and corneal endothelium to prevent nucleus fragments from coming into contact with the corneal endothelium. Outcome measures included cumulative dissipated energy (CDE), corneal edema (day one), CCT (assessed at one day, one week, and one month), and endothelial cell density assessed at three months.

Results

Of the 48 eyes included in the study, 23 were males and 25 were females (mean age: 70.02±5.98years). Preoperatively, mean central corneal thickness (CCT) was 529.62±21.70 microns, and endothelial cell counts were 2258.76±182.22 cells per mm². Postoperatively on day one, CCT increased to 563.93±24.53 microns, a 6.47% increase from preoperative central corneal thickness. CCT became 534.83±22.64 microns on postoperative day seven, a 0.98% increase from preoperative CCT. Endothelial cell loss was 6.77% at three months from the day of surgery.

Conclusion

The chopper shield technique offers continuous protection to the corneal endothelium by minimizing endothelial cell loss during phacoemulsification of dense nuclear cataracts.

Efficacy of intracameral antibiotics following manual small incision cataract surgery in reducing the rates of endophthalmitis: A meta-analysis

BACKGROUND

Manual small incision cataract surgery (MSICS) is a widely used technique for cataract surgery in the developing world. Higher rates of postoperative endophthalmitis have been reported with this technique compared with phaco-emulsification. The purpose of this study was to evaluate the efficacy of prophylactic intracameral (IC) antibiotics in reducing the rates of postoperative endophthalmitis following MSICS.

METHODS

Systematic review and meta-analysis of patients undergoing MSICS. A literature search in PubMed and EMBASE databases was performed to identify studies published from October 1992 to April 2020 evaluating MSICS with a minimum of 500 eyes reported. Two authors independently assessed eligibility, extracted data and assessed the risk of bias. Heterogeneity was assessed using the I² test.

RESULTS

Twelve studies enrolling 1 494 307 eyes were included. IC antibiotics were used in 725 324 (48.5%) eyes. The risk ratio of developing endophthalmitis was 2.94 (95% CI, 1.07-8.12; P = .037) in eyes that did not receive IC antibiotics.

CONCLUSIONS

Routine use of IC antibiotics may help to reduce the rates of endophthalmitis following MSICS and significantly improve the safety of this effective form of cataract surgery.

Combined treatment of phacoemulsification and single-port limited pars plana vitrectomy in acute angle-closure glaucoma

AIM

To evaluate the efficacy of combined treatment of phacoemulsification (PE) and micro-incisional single-port transconjunctival limited pars plana vitrectomy (PPV) in acute angle-closure glaucoma (AACG).

METHODS

A retrospective study included 26 patients who underwent PE diagnosed with AACG. Among them, 16 patients (16 eyes) underwent PE alone, 10 patients (10 eyes) underwent combined limited vitrectomy and PE. Then we compared intraocular pressure (IOP), anterior chamber angle, anterior chamber depth, central corneal thickness and corneal endothelial cell count before and after surgery, and effective PE time during cataract surgery.

RESULTS

Effective PE time was shorter in the combined surgery group than in the single surgery group (P=0.040). There was no statistically significant difference in IOP and best-corrected visual acuity between the two groups postoperatively. At 6mo postoperatively, there was no difference in the anterior chamber angle, anterior chamber depth, and central corneal thickness between two groups, but corneal endothelial cell count was higher in the combined surgery group than in the single surgery group (P=0.046). No complication such as vitreoretinal disease, endophthalmitis, bullous keratopathy was noted.

CONCLUSION

Combined micro-incisional single-port transconjunctival limited PPV and PE are more effective and safer than PE alone because of less operation time and fewer complications for management of AACG.

Torsional phacoemulsification: A pilot study to revise the "harm scale" evaluating the endothelial damage and the visual acuity after cataract surgery

PURPOSE

To study the effect of torsional phacoemulsification energy on corneal endothelium evaluating the relationship between changes of endothelial cells and postoperative visual acuity.

METHODS

This prospective clinical observational cohort study included 50 patients with cataract who underwent torsional phacoemulsification. Sequential quantitative and qualitative morphometric endothelial cell analyses of the cornea were performed four weeks preoperatively and six weeks postoperatively using noncontact specular microscopy.

RESULTS

This work confirmed the strong relationship, described by a linear model (one-way ANOVA, R2 = 77.9%, P < 0.0001), between the percentage of endothelial cell loss (ECL%) and the 5-score harm scale. According to the Tukey post-hoc pairwise comparison test, distinct values of ECL% are grouped in 3 subsets. The value of ECL = 10% has been identified as cut-off to discriminate patients with excellent postoperative best-corrected visual acuity (BCVA > 85 letters) from those with just a good/satisfied visual outcome (BCVA ≤ 85 letters). Within the 5-score harm scale, there was a significant correlation among phaco energy intraoperatively delivered and the average endothelial cell loss.

CONCLUSIONS

This study confirms the validity of the 5-score harm scale first proposed by Sorrentino and colleagues in 2016. This time, the method categorizes cataracts taking into account nucleus hardness and phaco cumulative dissipated energy. Predicting the harm on corneal endothelium, we can discriminate patients with excellent BCVA and with just good/satisfied BCVA. With torsional phacoemulsification with respect to longitudinal, the percentage of patients who can reach excellent BCVA is remarkably increased.

Comparison of central corneal thickness and endothelial cell measurements by Scheimpflug camera system and two noncontact specular microscopes

PURPOSE

To investigate the correlation of Scheimpflug camera system and two noncontact specular microscopes in terms of central corneal thickness (CCT) and corneal endothelial cell morphology measurements.

METHODS

One hundred eyes of 50 healthy subjects were examined by Pentacam Scheimpflug Analyzer, CEM-530 (Nidek Co, Ltd, Gamagori, Japan) and CellChek XL (Konan Medical, California, USA) via fully automated image analysis with no corrections made. Measurement differences and agreement between instruments were determined by intraclass correlation analysis.

RESULTS

The mean age of the subjects was 36.74 ± 8.59 (range 22-57). CCTs were well correlated among all devices, with having CEM-530 the thinnest and CellChek XL the thickest measurements (intraclass correlation coefficient (ICC) = 0.83; p < 0.001 and ICC = 0.78; p < 0.001, respectively). Mean endothelial cell density (ECD) given by CEM-530 was lower than CellChek XL (2613.17 ± 228.62 and 2862.72 ± 170.42 cells/mm², respectively; ICC = 0.43; p < 0.001). Mean value for coefficient of variation (CV) was 28.57 ± 3.61 in CEM-530 and 30.30 ± 3.53 in CellChek XL. Cell hexagonality (HEX) with CEM-530 was higher than with CellChek XL (68.70 ± 4.16% and 45.19 ± 6.58%, respectively).

CONCLUSIONS

ECDs with CellChek XL and CEM-530 have good correlation, but the values obtained by CellChek XL are higher than CEM-530. Measurements for HEX and CV differ significantly and show weak correlation. Thus, we do not recommend interchangeable use of CellChek XL and CEM-530. In terms of CCTs, Pentacam, CEM-530 and CellChek XL specular microscopy instruments are reliable devices.

[Phacoemulsification versus manual small incision cataract surgery: Anatomic and functional results]

PURPOSE

Prospective randomised study to compare the impact of phacoemusification (PHACO) and small incision cataract surgery (SICS) on endothelial structure (cell density and morphology) and refractive results (visual acuity, induced astigmatism).

METHODS

Prospective study of 57 patients (63 eyes) over 20 months (May 2012-January 2014) undergoing surgery by 2 experienced surgeons. We included patients with senile or presenile cataracts, LOCS III class 2, 3 and 4. Patients were randomized into 2 groups based on their birth month (group 1: PHACO [33]; group 2: SICS [30]). All pre- intra- and postoperative data were collected prospectively. The minimum follow-up was 6 months. We used the SPSS 18.0 for statistical analysis. Statistical tests used included the test-t Student, the Anova test, the Mann-Witney non-parametric test and the Khi² test. A threshold of significance was set at 0.05.

RESULTS

The mean preoperative endothelial cell density was 2447.5±225 c/mm² with no significant difference between the two groups (P=0.207). The mean percentage of hexagonality was 55.5±8.2% in groups 1 and 2. The most significant cell loss was during the first immediate postoperative period for both groups. At Day 15 postoperative, the decrease in cell loss was significant (P<0.001) with a mean loss of 312.9±208.9 c/mm² (P<10^-2). Postoperatively, the mean best-corrected visual acuity was 0.057 log MAR for all of our patients (P=0.170); no patient had an acuity ≤1/10. The mean astigmatism at the conclusion of follow-up was 1.08±0.42 D in group 1 and 1.51±0.55 D in group 2, with a significant difference (P=0.001).

CONCLUSION

Both SICS and PHACO give excellent results, both anatomical and refractive. However, SICS appears to be more advantageous than PHACO in terms of speed, cost, and independence from technology, and appears to be better suited to dense cataracts and mass surgery.

Pars Plana-Modified versus Conventional Ahmed Glaucoma Valve in Patients Undergoing Penetrating Keratoplasty: A Prospective Comparative Randomized Study

PURPOSE

To compare the outcome of pars-plana-modified Ahmed glaucoma valve (AGV) versus limbal-based conventional AGV into the anterior chamber, in patients undergoing penetrating keratoplasty (PK) for glaucoma with coexisting corneal diseases.

METHOD

In this prospective randomized clinical trial, 58 eyes of 58 patients with glaucoma and coexisting corneal disease were divided into two groups. Group 1 (29 eyes of 29 patients) included patients undergoing limbal-based conventional AGV into the anterior chamber (AC) along-with PK and group 2 (29 eyes of 29 patients) included those undergoing pars-plana-modified AGV along-with PK. Outcome measures included corneal graft clarity, intraocular pressure (IOP), number of antiglaucoma medications, and postoperative complications. Patients were followed up for a minimum period of 2 years.

RESULTS

Out of 58 eyes (58 patients), 50 eyes (50 patients: 25 eyes of 25 patients each in group 1 and group 2) completed the study and were analyzed. Complete success rate for AGV (group 1: 76%; group 2: 72%; p = 0.842) and corneal graft clarity (group 1: 68%; group 2: 76%; p = 0.081) were comparable between the two groups at 2 years. Graft failure was more in conventional AGV (32%) as compared to pars plana-modified AGV (24%) but not statistically significant (p = 0.078) at 2 years.

CONCLUSION

Though both procedures were comparable in various outcome measures, pars-plana-modified AGV is a viable option for patients undergoing PK, as it provides a relatively better corneal graft survival rate and lesser complications that were associated with conventional AGV.

A Pilot Study to Propose a "Harm Scale", a New Method to Predict Risk of Harm to the Corneal Endothelium Caused by Longitudinal Phacoemulsification, and the Subsequent Effect of Endothelial Damage on Post Operative Visual Acuity

PURPOSE

To study the effect of longitudinal phacoemulsification energy on corneal endothelium and to evaluate the relationship between changes of endothelial cells and postoperative visual acuity.

METHODS

This prospective clinical observational cohort study included 50 patients with cataract who underwent longitudinal phacoemulsification. Sequential quantitative and qualitative morphometric endothelial cell analyses of the cornea were performed 4 weeks preoperatively and 6 weeks postoperatively using noncontact specular microscopy.

RESULTS

There was a relationship between ECL percentage (ECL%) and the 5-score harm scale, well-described by a linear model (one-way ANOVA, R2 = 73.3%). Analyzing the distribution of ECL% Mean with Tukey post-hoc pairwise comparison test (P < 0.001), the value of ECL = 20% has been regarded as cut-off to discriminate patients who obtained an excellent postoperative best-corrected visual acuity (BCVA > 85 letters) from those who just had a good visual outcome (BCVA ≤ 85 letters). There was a significant correlation among the 5-score harm scale, phaco energy intraoperatively delivered, and average cell area postoperatively.

CONCLUSIONS

The 5-score harm scale, a new method that enables to pigeonhole cataracts taking into account nucleus hardness and phaco times, allows to predict the harm on corneal endothelium after longitudinal phacoemulsification. Assessment of ECL% permits to discriminate between patients with excellent BCVA and with just good BCVA, postoperatively.

Advances in cataract surgery: preserving the corneal endothelium

PURPOSE OF REVIEW

Cataract surgery is known to lead to some degree of corneal endothelial cell loss (ECL). The purpose of this review is to describe how recent technological advancements such as femtosecond laser-assisted cataract surgery (FLACS) affect corneal endothelium during cataract surgery.

RECENT FINDINGS

It has been suggested that FLACS may reduce the amount of required ultrasound energy used in cataract surgery, a factor known to be directly related to ECL. Several recent studies demonstrate either no difference or less ECL with FLACS than with standard phacoemulsification 1-3 months after surgery. However, results at 6 months show comparable ECL between the two techniques. Other recent advancements in surgical technique, such as biaxial microincision surgery, result in similar ECL rates to that of standard phacoemulsification. The use of ultraviolet light in the newly developing light-adjustable intraocular lenses does not increase ECL. Studies show either similar results or less ECL with the use of the newer viscous-dispersives when compared with other viscoelastic devices. Other aspects such as the use of intracameral injections have no adverse effects on corneal endothelium.

SUMMARY

Newly emerging cataract surgical techniques cause comparable ECL to that of conventional phacoemulsification. Femtosecond laser-assistance may reduce ECL, but likely only in the early postoperative period. Further studies are needed to better elucidate short and long-term effects of FLACS on the corneal endothelium. Viscous dispersives may offer equal or increased protection of the corneal endothelium during surgery compared with viscoelastic devices currently in wide use, but further studies are required to support these results.