Preoperative Endothelial Cell Density Research Articles

Causes and outcomes of implantable collamer lens explantation in patients with corneal endothelial cell loss.

To investigate the correlated factors of corneal endothelial cell density (ECD) loss and ECD change in implantable collamer lens (ICL) explantation patients. Seoul St. Mary's Hospital, Seoul, South Korea. Retrospective analysis. The study cohort consisted of 93 eyes from 50 patients who underwent ICL explantation. Correlation analysis was performed to assess the ocular parameters associated with ECD loss, while percentage of ECD change (ΔECD%) was monitored up to 6 months postoperatively. Receiver operating characteristic (ROC) curve was used to set cutoff values of ocular parameters to prevent ECD loss after explantation. In multiple regression analysis, high vaulting, high vaulting/anterior chamber depth (ACD), low anterior chamber angle (ACA), and high iris pigmentations are the significant factors of ECD loss. At postoperative 6 months, 14 eyes (15.1%) had decrease (10.5% loss), 47 eyes (51.0%) were stationary, and 32 eyes (34.4%) had increase (12.7% gain) of ECD. The ROC curve analysis showed that vaulting had the highest area under the curve (AUC = 0.822), followed by vaulting/ACD (AUC = 0.821), ECD (AUC = 0.753), and ACA (AUC = 0.723) (all P < .01). Preoperative ECD showed a sensitivity of 77.6% and specificity of 86.7% in preventing ECD loss after explantation, with a cutoff value of 1722 cells/mm 2 , as determined by ROC curve analysis. Our study demonstrated that high vaulting is a significant factor in ECD loss among ICL-inserted patients. To prevent continuous ECD loss in ICL patients, close monitoring of ECD and making appropriate decisions regarding explantation may be necessary.

Narrative review after post-hoc trial analysis of factors that predict corneal endothelial cell loss after phacoemulsification: Tips for improving cataract surgery research.

Identifying pre/perioperative factors that predict corneal endothelial-cell loss (ECL) after phacoemulsification may reveal ways to reduce ECL. Our literature analysis showed that 37 studies have investigated one or several such factors but all have significant limitations. Therefore, the data of a large randomized controlled trial (PERCEPOLIS) were subjected to post-hoc multivariate analysis determining the ability of nine pre/perioperative variables to predict ECL. PERCEPOLIS was conducted in 2015-2016 to compare two phacoemulsification techniques (subluxation and divide-and-conquer) in terms of 3-month ECL. Non-inferiority between the techniques was found. In the present study, post-hoc univariate and multivariate analyses were conducted to determine associations between ECL and age, sex, cataract density, preoperative endothelial-cell density, phacoemulsification technique, effective phaco time (EPT), and 2-hour central-corneal thickness. The data are presented in the context of a narrative review of the literature. Three-month data were available for 275 patients (94% of the randomized cohort; mean age, 74 years; 58% women). Mean LOCSIII cataract grade was 3.2. Mean EPT was 6 seconds. Mean ECL was 13%. Only an older age (beta = 0.2%, p = 0.049) and higher EPT (beta = 1.2%, p = 0.0002) predicted 3-month ECL. Cataract density was significant on univariate (p = 0.04) but not multivariate analysis. The other variables did not associate with ECL. Older age may amplify ECL due to increased endothelial cell fragility. EPT may promote ECL via cataract density-dependent and -independent mechanisms that should be considered in future phacoemulsification research aiming to reduce ECL. Our literature analysis showed that the average ECL for relatively unselected consecutively-sampled cohorts is 12%.

The effect of irrigation and aspiration on the corneal endothelial cell density in patients undergoing Implantable Collamer Lens with a central hole implantation for myopia correction.

In the conventional technique, viscoelastic agents are typically rinsed away with balanced salt solution (BSS), but it may lead to a series of complications such as viscoelastic residue, anterior chamber instability and intraoperative TICL rotation. The utilization of irrigation and aspiration (I/A) has been shown to be effective in maintaining anterior chamber stability, reducing the incidence of postoperative high intraocular pressure, and minimizing postoperative fundus complications. However, there is a lack of previous studies investigating the impact of I/A on corneal endothelial cells during ICL implantation. The objective of this study was to examine the effect of I/A on corneal endothelial cells in patients undergoing myopia correction through implantation of Implantable Collamer Lens with a central hole (V4c ICL). A retrospective selection was made of 344 eyes from 172 patients who underwent V4c ICL implantation and I/A to remove viscoelastic agent from the anterior chamber between 2021 and 2022. The intraocular pressure (IOP) was measured at 1h, 2h and 3h after surgery. Corneal endothelial cell density (ECD), coefficient of variation in cell size (CV), standard deviation of cell area (SD), and percentage of hexagonal cells (HEX) were evaluated at 1week postoperatively to assess corneal endothelial cells. The first two represent polymegethism or morphological variation, while the third parameter represents the degree of polymorphism of the corneal endothelial cells. Electronic medical records were utilized for data collection purpose. All surgeries proceeded without complications. The IOP was 16.50 ± 3.42mmHg (range: 11.5-22.3mmHg) prior to surgery and increased to 21.25 ± 5.61mmHg (range: 9.5-34.8mmHg), 19.85 ± 5.18mmHg (range: 11.4-36.2mmHg) and finally settled at an average of 18.81 ± 4.57mmHg (range: 10.1-38.8mmHg) at the respective time points of 1h, 2h and 3h after surgery. The preoperative ECD was recorded as being approximately 3004 ± 295 cell/mm2, which exhibited a marginal decreased of 1.17% postoperatively, resulting in an average ECD value of 2969 ± 303 cell/mm2 one week after surgery (P = 0.12). Similarly, the preoperative CV was determined as 31.10 ± 3.78%, and it experienced a slight reduction with an average CV value of 30.74 ± 3.77% at week after surgery (P = 0.21). And, the preoperative SD was reported as 104.76 ± 17.26, and it remained virtually unchanged with an average SD value of 104.85 ± 18.75 at one week after surgery (P = 0.95). The preoperative HEX was calculated as 55.38 ± 8.94%, and it remained its stability with an average HEX value of 55.45 ± 8.73% one week after surgery (P = 0.92). The utilization of I/A led to a slight decrease in postoperative ECD when compared to conventional surgical techniques. Nevertheless, the reduction in ECD remained within acceptable limits, taking into accout the avervantaged it offered, such as stabilization of the anterior chamber and decreased occurrence of viscoelastic residue after surgery. It is challenging to anticipate the long-term safety of corneal endothelial cells based on current short-term studies. However, this study provides a valuable reference indicating that neither anterior chamber irrigation nor I/A aspiration have an adverse impact on the safety of corneal endothelial cells in the short term. Further research is imperative to enhance our understanding of their effects over an extended period.

Hemi-Ultrathin Descemet Stripping Automated Endothelial Keratoplasty (Hemi-UT-DSAEK) Using Pediatric Donor Corneas: A Case Series.

We sought to evaluate the clinical outcomes of hemi-UT-DSAEK grafts from the pediatric donor corneas of patients affected by Fuchs Endothelial Corneal Dystrophy (FECD). A prospective, interventional case series was conducted at the Ophthalmology Department of Venice Civil Hospital and the Veneto Eye Bank Foundation (Venice, Italy). Six eyes of six patients affected by FECD received large-diameter, semicircular hemi-UT-DSAEK grafts obtained from three pediatric donor corneas using the standard pull-through method. Endothelial cell density (ECD), central corneal thickness (CCT), best-corrected visual acuity (BCVA) and intraoperative and postoperative complications were recorded at different time intervals up to 12 months. The average donor age was 64.6 ± 8.6 years, and the pre-operative ECD was 3266 ± 225 cells/mm2. At 12 months postoperatively, the average ECD was 1376 ± 509 cells/mm2 with a mean decrease of 56.8 ± 19.1% from the preoperative donor count. At 12 months, four out of six eyes had significantly improved and reached a BCVA of ≥20/25 (Snellen equivalent). The mean CCT significantly decreased from 788 ± 138 μm before surgery to 576 ± 30 μm at 12 months postoperatively (p < 0.01). Hemi-UT-DSAEK grafts using pediatric donor corneas are surgically feasible and can provide similar clinical outcomes compared to conventional UT-DSAEK. Transplanting pediatric donor tissues with high ECD into two patients could potentially increase the donor tissue pool to treat endothelial disease.

Clinical Outcomes of Descemet Membrane Endothelial Keratoplasty Using a Preloaded Imported Graft.

Although the popularity of Descemet membrane endothelial keratoplasty (DMEK) is increased, there is still few clinical studies in Korea. In this study, we aimed to report the initial clinical outcomes of DMEK in patients followed up for more than 6 months. A total of 96 eyes that underwent DMEK by a single surgeon for Fuchs endothelial corneal dystrophy, pseudophakic bullous keratopathy, or other indications were evaluated for best-corrected visual acuity (BCVA), endothelial cell density (ECD), central corneal thickness (CCT), postoperative complications, and graft survival. The postoperative BCVA significantly increased compared to the preoperative BCVA by 59.4% (1.00 ± 0.77 logarithm of the minimum angle of resolution vs. 0.67 ± 0.76 logarithm of the minimum angle of resolution, p &lt; 0.001). The average preoperative ECD was 754 ± 382 cells/mm2, increasing to 1,333 ± 562 cells/mm2 at 3 months (76.8%, p &lt; 0.001), 1,334 ± 632 cells/mm2 at 6 months (76.9%, p &lt; 0.001), 1,121 ± 474 cells/mm2 at 12 months (48.7%, p = 0.024), and 972 ± 458 cells/mm2 at 24 months postoperatively (28.9%, p = 0.445). Compared to 3 months, the ECD declined by 15.9% at 12 months (p = 0.009) and 27.1% at 24 months postoperatively (p = 0.158). The average CCT was 675 ± 113 μm preoperatively, decreasing to 581 ± 102, 574 ± 101, and 594 ± 94 μm at 6, 12, and 24 months after DMEK, respectively (p &lt; 0.001 between all follow-up time points). Allograft rejection was detected in three (3.1%) and 14 eyes (14.6%) underwent retransplantation at an average of 10.1 ± 8.4 months after DMEK. DMEK is promising for maintaining corneal clarity, low postoperative complication rates, and stable graft longevity.

Safety of intracameral application of moxifloxacin and dexamethasone (Vigadexa®) after phacoemulsification surgery

BackgroundIntracameral antibiotics, such as moxifloxacin and cefuroxime, are safe to corneal endothelial cells and effective prophylaxis of endophthalmitis after cataract surgery. Corneal endothelial cells decrease in density after cataract surgery. Any substance used in the anterior chamber may affect corneal endothelial cells and lead to a greater decrease in density. This study wants to determine the percentage of endothelial cell loss after cataract extraction by phacoemulsification with off-label intracameral injection of moxifloxacin and dexamethasone (Vigadexa®).MethodsAn observational retrospective study was performed. The clinical records of patients undergoing cataract surgery by phacoemulsification plus intracameral injection of Vigadexa® were analyzed. Endothelial cell loss (ECL) was calculated using preoperative and postoperative endothelial cell density. The relation of endothelial cell loss with cataract grade using LOCS III classification, total surgery time, total ultrasound time, total longitudinal power time, total torsional amplitude time, total aspiration time, estimated fluid usage, and cumulative dissipated energy (CDE) was studied using univariate linear regression analysis and logistic regression analysis.ResultsThe median loss of corneal endothelial cells was 4.6%, interquartile range 0 to 10.4%. Nuclear color and CDE were associated with increased ECL. ECL>10% was associated with age and total ultrasound time in seconds.ConclusionsThe endothelial cell loss after the intracameral use of Vigadexa® at the end of cataract surgery was similar to the reported in other studies of cataract surgery without the use of intracameral prophylaxis for postoperative endophthalmitis (POE). This study confirmed the association of CDE and nuclear opalescence grade with postoperative corneal endothelial cell loss.

The effect of accelerated pulsed high-fluence corneal cross-linking on corneal endothelium; a prospective specular microscopy study

BackgroundCorneal collagen cross-linking (CXL) is a procedure utilized for halting keratoconus progression with different approved protocols. The current study aimed to assess the corneal endothelial changes following the relatively new accelerated pulsed high-fluence protocol of epithelium-off corneal cross-linking for the treatment of mild to moderate keratoconus.MethodsThis prospective case series study enrolled 45 eyes of 27 patients with mild to moderate progressive keratoconus who underwent accelerated pulsed high-fluence CXL (pl-ACXL, 30 mW/ cm2 UVA at 365 nm wavelength, 8 min pulsed mode 1 s on / 1 s off with a total energy of 7.2 J/ cm2). The main outcome measures were corneal endothelial changes assessed by specular microscopy at 3 and 6 months postoperatively including endothelial cell density (ECD), coefficient of variation, percentage of hexagonal cells, average, minimum and maximum endothelial cell sizes. Demarcation line depth was assessed 1 month following surgery.ResultsThe mean age of the studied sample was 24.89 ± 7.21. The mean preoperative ECD (2944.6 ± 247.41 cell/mm2) showed non-significant reduction at 3 and 6 months postoperatively (2931.03 ± 253.82 and 2924.7 ± 224.88 cell/mm2, respectively, P-value = 0.361). There were no significant changes in the mean coefficient of variation, percentage of hexagonal cells, average, minimum and maximum endothelial cell sizes at 3 and 6 months following pl-ACXL (P-value > 0.05). The mean demarcation line depth 1 month after pl-ACXL was 214 ± 17.43 μm.ConclusionsCorneal endothelial changes following accelerated pulsed high-fluence CXL were minimal with stability of endothelial cell count and non-significant morphological changes.Trial RegistrationClinicaltrials.gov: NCT04160338 (13/11/2019).

Long-term results of a new posterior chamber phakic intraocular lens in patients with high myopia: 5-year results.

To evaluate the long-term refractive outcomes of Eyecryl posterior chamber spherical phakic intraocular lens (pIOL) implantation in high myopia and endothelial cell density (ECD) change. Beyoglu Eye Training and Research Hospital, Istanbul, Turkey. Retrospective. Eyes that were not suitable for corneal refractive surgery, had high myopia between -6.00 diopters (D) and -20.00 D, had Eyecryl posterior chamber spherical pIOL implantation, and had at least 5 years of follow-up were included. Preoperative ECD was ≥2300 cells/mm 2 and cylindrical value was ≤2.0 D in all cases. Preoperative and postoperative first, third, and fifth years of refraction, uncorrected and corrected distance visual acuity (UDVA/CDVA), and ECD were recorded. 36 eyes of 18 patients were examined. The mean UDVA and CDVA in postoperative fifth years were 0.24 ± 0.19 logMAR and 0.12 ± 0.18 logMAR, respectively. The safety and efficacy indices were 1.52 ± 0.54 and 1.14 ± 0.38, respectively. At 5 years, the spherical equivalent was ±0.50 D in 75% of eyes and ±1.00 D in 92% of eyes. After 5 years, the mean cumulative ECD loss was 6.91% ( P = .07). The annual ECD loss was 1.57% in the first year, 0.26% between 1 year and 3 years, and 2.38% between 3 years and 5 years. Asymptomatic anterior capsule opacity developed in 1 eye 4 years after surgery. Rhegmatogenous retinal detachment developed in 1, and myopic choroidal neovascular membrane occurred in 1 eye. Eyecryl posterior chamber spherical pIOL implantation is one of the effective and safe refractive surgical methods in correcting high myopia with predictable and stable refractive results over a 5-year period. Longer-term studies are needed for complications such as decreased ECD, retinal complications, and lens opacity.

Impact on corneal morphology after cataract surgery with intracameral moxifloxacin in neglected hard cataracts.

To evaluate corneal morphology after use of 0.5% intracameral moxifloxacin (ICM) in cataract surgery in patients who presented late with hard cataracts. Cross-sectional study conducted from June-2021 to December-2021 at a tertiary eye-care center. 90 patients over 60 years with high-risk characteristics for Covid-19, who presented late with higher grades of nuclear-sclerosis (NS), were included. They underwent phacoemulsification and 0.5%moxifloxacin (0.1 ml) was injected intracamerally at the end of surgery. Best-corrected visual acuity (BCVA), intraocular pressures (IOP), endothelial cell density (ECD), coefficient of variation in cell-area (CoV), hexagonality (Hex) and central corneal thickness (CCT) were measured preoperatively and postoperatively on day1, day7 and day30. Statistical analysis was done by Anova test. p-value<0.05 was considered significant. Mean age of presentation was 65.26±8.3 years. Mean preoperative BCVA (1/60-to-6/60), IOP (16.7±2.3 mm of Hg), CCT (523.93±39.6µ), ECD (2547±302.08cells/mm2), Hex (47.04±5.7%) and CoV (37.57±3.9) changed to BCVA (6/9-to-6/6), IOP (17.5±2.1 mm of Hg), CCT (538.42±36.9µ), ECD (2388.40±339.25cells/mm2), Hex (44.44±5.6%) and CoV (39.09±4.5) at day30 postoperative. Average rate of change at day30 was increase in CCT (2.89%), ECD loss (6.4%), decrease in Hex (4.9%) and increase in CoV (4.6%), though clinically insignificant. No case of endophthalmitis or toxic-anterior segment syndrome seen. 0.5% moxifloxacin (0.1 ml) is safe as intracameral antibiotic to prevent postoperative infection in high-risk patients. The reported changes in the corneal parameters were within the range of any routine surgeries of hard senile cataracts. No specific effect could be attributed to ICM.

Identification of the preoperative and perioperative factors that predict postoperative endothelial cell density after Descemet membrane endothelial keratoplasty: A retrospective cohort study.

Low postoperative endothelial-cell density (ECD) plays a key role in graft failure after Descemet-membrane endothelial keratoplasty (DMEK). Identifying pre/perioperative factors that predict postoperative ECD could help improve DMEK outcomes. This retrospective study was conducted with consecutive adult patients with Fuchs-endothelial corneal dystrophy who underwent DMEK in 2015-2019 and were followed for 12 months. Patients underwent concomitant cataract surgery (triple-DMEK) or had previously undergone cataract surgery (pseudophakic-DMEK). Multivariate analyses assessed whether: patient age/sex; graft-donor age; preoperative ECD, mean keratometry, or visual acuity; triple DMEK; surgery duration; surgical difficulties; and need for rebubbling predicted 6- or 12-month ECD in the whole cohort or in subgroups with high/low ECD at 6 or 12 months. The subgroups were generated with the clinically relevant threshold of 1000 cells/mm2. Surgeries were defined as difficult if any part was not standard. In total, 103 eyes (95 patients; average age, 71 years; 62% women) were included. Eighteen eyes involved difficult surgery (14 difficult graft preparation or unfolding cases and four others). Regardless of how the study group was defined, the only pre/perioperative variable that associated significantly with 6- and 12-month ECD was difficult surgery (p = 0.01, 0.02, 0.05, and 0.0009). Difficult surgery also associated with longer surgery duration (p = 0.002). Difficult-surgery subgroup analysis showed that difficult graft dissection associated with lower postoperative ECD (p = 0.03). This association may reflect endothelial cell loss due to excessive graft handling and/or an intrinsic unhealthiness of the endothelial cells in the graft that conferred unwanted physical properties onto the graft that complicated its preparation/unfolding.

Corneal endothelial evaluation after phacoemulsification in eyes with pseudoexfoliation syndrome

Purpose The aim of this study was to evaluate the corneal endothelial cell changes after phacoemulsification in patients with age-related cataract and pseudoexfoliation (PEX) syndrome compared with control patients having age-related cataract using specular microscopy.Patients and methods In this prospective interventional case–control study, 20 eyes with cataract and PEX and 20 control eyes with cataract without PEX were subjected to phacoemulsification and posterior chamber foldable intraocular lens implantation at Minia University Hospital and Genaidy Eye Center, Minia, Egypt, between March 2019 and December 2020. Specular microscopy was done preoperatively and at 3 and 6 months postoperatively. The endothelial cell density (ECD), coefficient of variation, hexagonality (HEX%), pleomorphism, and corneal thickness were evaluated and compared between PEX and control eyes.Results The median best-corrected visual acuity improved significantly from a preoperative value of 0.3 in both groups to 0.5 and 0.6 in PEX and control groups, respectively, at 3 and 6 months postoperatively (P<0.001). In patients with PEX, the preoperative median ECD significantly decreased from 2790.5 cells/mm2 to 2387 at 3 months (P<0.001) and to 2380 cells/mm2 at 6 months (P<0.001). In the control group, the preoperative median ECD significantly decreased from 2599 to 2364 cells/mm2 at 3 months (P<0.001) and to 2353 cells/mm2 at 6 months (P<0.001). There was a statistically insignificant difference between the two groups regarding the preoperative and third and sixth postoperative month ECD (P=0.499, 0.850, and 0.860, respectively). The median of HEX% decreased significantly in the PEX eyes from a preoperative value of 45.5 to 39% at 3 months (P<0.001) and to 38% at 6 months (P<0.001). In the control eyes, the HEX% decreased significantly from a preoperative value of 42 to 38.5% at 3 months (P=0.009) and to 37% at 6 months (P<0.012). There was no statistically significant difference between the preoperative and postoperative values of the coefficient of variation % in either group, with no statistically significant difference between the two groups. In addition, there was no statistically significant difference between the two groups either before or after surgery in the central corneal thickness.Conclusion Although the percentage of reduction in ECD was more in the PEX eyes compared with the control eyes after phacoemulsification, there was no statistically significant difference in most of the studied parameters between the two groups.

Effect of Myopic Femtosecond Laser-Assisted LASIK on Anterior Chamber Inflammation (Flare Values) and Corneal Endothelium: A Prospective before and after Study.

Purpose This study aimed to investigate whether femtosecond laser-assisted LASIK (FS-LASIK) surgery causes inflammation in the anterior chamber and to analyze its effect on endothelial cells. Methods This prospective, longitudinal study included left eyes of 30 patients (19 females) who had undergone FS-LASIK surgery due to myopia and myopic astigmatism. Endothelial cell density (ECD) and morphological measurements were performed using a specular microscopy, and laser flare photometry was used to measure the anterior chamber flare values on the day of surgery. iFS™ Advanced FS and VISX STAR S4-IR Wavescan Excimer Laser platforms were used. Flare measurements were repeated on the postoperative 1st day and 7th day and the 1st and 3rd months. The endothelial measurements were repeated in the 3rd month. Results Preoperatively, the mean flare was 5.59 ± 1.24 photons/ms; it was 6.49 ± 2.42 on the postoperative 1st day, 5.87 ± 2.27 on the 7th day, 5.68 ± 1.66 on the 1st month, and 5.35 ± 1.24 on the 3rd month. A significant difference was observed only between the preoperative and postoperative 1st day flare values (p=0.047). The decrease in the ECD was clinically insignificant but statistically significant, with an average of 97.0 ± 209.9 cell count/mm2 (3.3%, p=0.017). However, there was no significant change in the coefficient of variation (p=0.448) and hexagonality (p=0.096). No significant correlation was found between the increase in the flare value on the postoperative 1st day and variables. A significant correlation was found between the decrease in ECD and the preoperative ECD (r = 0.356, p=0.027). Conclusion FS-LASIK caused minimal inflammation in the anterior chamber on only the 1st postoperative day; additionally, a minimal decrease of cell count with no morphological changes were noted in the endothelial cells on postoperative 3rd month. This trial is registered with NCT04899258.

Comparison of Donor Corneal Endothelial Cell Density Determined by Eye Banks and by a Central Image Analysis Reading Center Using the Same Image Analysis Method.

The purpose of this study was to evaluate agreement between eye banks (EBs) and an image analysis reading center on endothelial cell density (ECD) determinations using the same image analysis method. The Cornea Image Analysis Reading Center (CIARC) determined ECD with a single experienced analyst on EB-obtained central endothelial images from donors intended for keratoplasty from 2 eye banks, Eversight and Lions VisionGift, using the Konan center analysis method. The EBs performed ECD determination on their respective sets of images using the same analysis method with experienced eye bank technicians. The mean age of the 200 donors was 54 years (range 30-75 years). Seventy (35%) of the 200 patients were women, and 57 (29%) were diabetic. The mean ECD was 10 cells/mm2 greater by the EBs than by CIARC (P = 0.39), with 95% limits of agreement of [-304 to 323 cells/mm2]. The mean difference was not substantially changed when the difference between EBs and CIARC ECD was adjusted for sex, donor age, donor diabetes, CV, HEX, number of cells analyzed, and EBs as a random effect (estimated mean difference of 20 cells/mm2 after adjustment in a linear mixed model; P = 0.73). The EB-determined preoperative ECD was within 10% of the CIARC-determined ECD for 178 (89%) image sets, with 15 (8%) higher by >10% and 7 (3%) lower by >10%. Well-trained eye bank technicians achieve comparable results for ECD determination with an experienced image analyst from an image analysis reading center when the same image analysis method is used.

A comparative study of divide and conquer, stop and chop and phaco chop techniques of nucleotomy in phacoemulsification

Phacoemulsification is a variant of extracapsular cataract extraction surgery which is the gold standard treatment modality for cataract surgery nowadays. The common nucleotomy techniques of phacoemulsification are divide and conquer, stop and chop and phaco chop.Aim of this studyto compare different techniques of nucleotomy during phacoemulsification with respect to corneal endothelial cell loss, central corneal thickness (CCT) and comment on their merits and demerits. 60 patients undergoing cataract surgery by phacoemulsification were randomly divided into three groups of 20 each (Group A, B and C) who underwent nucleotomy by divide and conquer, stop and chop and phaco chop technique respectively. The preoperative endothelial cell density and central corneal thickness were recorded using Topcon SP3000P non-contrast specular microscope. All patients were followed up at 1, 4 and 12week after surgery and evaluated for vision, slit lamp examination, endothelial cell count and central corneal thickness.The age group of patients studied was 50-80 years, where maximum number of patients were in 51-60 years age group. Out of 60 patients, most common morphological type of cataract was nuclear (40%) cataract followed by cortico-nuclear (36.67%) cataract. After 1 week of surgery, drop in endothelial cell density was 7.06% in Group A, 6.49% in Group B and 6.84% in Group C patients. A further slight decrease in endothelial cell count was recorded during 4week and on final follow up visit at 12 weeks after cataract surgery, there was an endothelial cell loss of 9.51%, 10.9% and 11% in Group A, B and C respectively. The central corneal thickness at 1postoperative week increased by 2.75%, 2.35% and 2.20% in group A, B and C respectively. Further evaluation of CCT at 4and 12 week after surgery showed the values to be almost same as preoperative values. The rate of complications, which mainly included postoperative keratitis, mild anterior uveitis and cystoid macular edema, were found to be almost the same in all the three study groups.All the three nucleotomy techniques of phacoemulsification i.e divide and conquer, stop and chop and phaco chop are equally efficacious in terms of CCT changes, endothelial cell loss and complications rate in the hands of an experienced surgeon.

The effects of trypan blue use on the corneal endothelium during cataract surgery in patients with pseudoexfoliation syndrome (PEX)

Purpose In the present clinical study, it was aimed to investigate the possible effects of Trypan blue (TB) use on the corneal endothelium during cataract surgery in eyes with pseudoexfoliation syndrome (PEX) during a three-month follow-up period using the contralateral eye control design. Methods This prospective, randomised controlled, individual cohort study included 92 eyes of 46 patients with bilateral PEX and cataracts. While 1% TB was applied to one eye of the patients before capsulorhexis (study group), it was not applied to the other eye (control group). Both groups were compared preoperatively and postoperatively in terms of endothelial cell density (ECD), endothelial cell loss (%), pleomorphism, polymegathism and central corneal thickness (CCT) using specular microscopy. Results Preoperative corneal ECD was measured as 2362.56 ± 253.27 in the study group, 2380.84 ± 220.54 in the control group, and 2145.58 ± 221.71 in the study group and 2184.97 ± 200.94 cells/mm2 in the control group in the postoperative 3rd-month follow-up (p = 0.71 and = 0.37, respectively). In addition, there were no significant differences between the two groups in terms of the percentage of hexagonal cells, coefficient of variation (CV), and CCT both preoperatively and postoperatively 3 months later (p = 0.78, =0.39, =0.95 preoperatively and p = 0.31, =0.26, =0.83 postoperatively, respectively). Conclusion This study demonstrated that the injection of 1% TB into the anterior chamber for staining the anterior capsule during cataract surgery did not cause significant corneal endothelial changes at postoperative 3rd months, despite the increased fragility of corneal endothelial cells in patients with PEX.

Efficacy of Voriconazole Corneal Intrastromal Injection for the Treatment of Fungal Keratitis

Purpose To evaluate efficacy and safety of novel tricyclic corneal stroma injection (TCSI) voriconazole for the treatment of fungal keratitis. Methods This retrospective cohort study included data of 57 patients (57 eyes) with fungal keratitis. The TCSI group consisted of 27 patients (27 eyes) who were injected voriconazole once via TCSI procedure within one week after enrollment, in addition to conventional antifungal treatment. The control group consisted of 30 patients (30 eyes) who were treated using conventional antifungal treatment modalities. The outcome measures consist of the 3-week and 3-month best-corrected visual acuity (BCVA) values and size of infiltrate or scar, time to re-epithelialization, corneal perforation rate and/or therapeutic penetrating keratoplasty (TPK) requirement, the preoperative and post-TCSI corneal endothelial cell density (ECD), and the intraocular pressure (IOP) of the treated eye and the respective contralateral eye. Results There were no significant differences in the baseline demographic and clinical characteristics between the two groups. 3 weeks and 3 months after enrollment, the TCSI group exhibited an increase in visual acuity (P < 0.05), and there was no significant difference in the size of infiltrate or scar between two groups (P > 0.05). Time to re-epithelialization was shorter in the TCSI group than in the control group (P < 0.05). There was no statistically significant difference between corneal ECD on the day before and 7 days after TCSI and the IOP of treated and contralateral healthy eyes on the day before and 1 day, 3 days, 7 days, and 1 month after TCSI (P > 0.05). The difference in the risk of perforation and/or TPK requirement was not statistically significant between two groups (P > 0.05). Conclusion Localized injection of voriconazole using TCSI may be a minimally invasive, safe, and effective adjuvant treatment modality for fungal keratitis.

Corneal endothelial cell changes and surgical results after Ahmed glaucoma valve implantation: ciliary sulcus versus anterior chamber tube placement

We compared the changes in corneal endothelial cells and surgical outcomes after Ahmed glaucoma valve (AGV) implantation with the valve tip inserted either into ciliary sulcus (CS) or anterior chamber (AC). We retrospectively reviewed the medical records of patients treated with CS AGV (n = 24) and AC AGV (n = 38). We compared the preoperative and postoperative central corneal endothelial cell density (ECD), endothelial cell coefficient of variation (CV), best-corrected visual acuity, intraocular pressure (IOP), number of glaucoma medications, and postoperative complications in the two groups. Both groups had similar baseline characteristics and follow-up period. At the last follow-up, the AC AGV group had significantly higher mean monthly ECD loss (17.47 ± 11.50 cells/mm2 vs. 6.40 ± 7.69 cells/mm2, p < 0.0001) and greater proportion of mean monthly ECD loss than the CS AGV group (0.84 ± 0.53 vs. 0.36 ± 0.39%, p < 0.0001). Both groups had similar mean monthly CV changes. The qualified success rates at 2 years were 83.3% and 76.3% for the CS AGV and AC AGV groups, respectively. Although similar surgical outcomes including visual acuity, IOP, number of glaucoma medications, and postoperative complications were obtained following CS AGV and AC AGV, corneal ECD loss was higher in the AC AGV group. Thus, CS AGV may be a better surgical option than AC AGV.

Accelerated Corneal Endothelial Cell Loss after Phacoemulsification in Patients with Mildly Low Endothelial Cell Density.

By evaluating preoperative endothelial cell density (ECD), ECD loss after phacoemulsification can be predicted. In this retrospective cross-sectional study, we compared outcomes of phacoemulsification with different levels of preoperative ECD. Three-hundred-and-fifty-three patients aged between 18 and 90 years received phacoemulsification at Chang Gung Memorial Hospital. Age (p = 0.003), preoperative logMAR (p = 0.048), cataract grade (p = 0.005), preoperative ECD (p < 0.001), operation time (p = 0.043), phacoemulsification time (p = 0.001), and phacoemulsification energy (p < 0.001) were significantly associated with postoperative ECD change (%). Patients were divided into three groups according to preoperative ECD levels. Level of ECD, coefficient of variation (CV), cell hexagonality (HEX), central corneal thickness (CCT), visual acuity, underlying diseases, and complications were analyzed. With regard to groups, 29, 71, and 252 patients were respectively allocated into the markedly low (group A; ECD below 1000 cells/mm2), mildly low (group B; ECD between 1000 to 2000 cells/mm2), and normal (group C; ECD above 2000 cells/mm2) ECD level groups. The highest CV (40.8 ± 13.9%; p < 0.001) and lowest HEX (58.4 ± 14.6%; p < 0.001) were found in group A. Significant ECD loss was found in group B (28.9 ± 9.2%) as compared to group A (19.9 ± 5.4%) and C (15.0 ± 12.0%) (p < 0.001). No significant differences were found with regard to changes in CV (p = 0.941), HEX (p = 0.937), CCT (p = 0.346), and logMAR (p = 0.557) among the three groups. In conclusion, preoperative ECD level could be a novel predictive value for postoperative cell loss, which was the most prominent in mildly low ECD level group. Less phacoemulsification energy, earlier surgical intervention, or novel topical medications could be suggested for patients with an ECD range from 1000 to 2000 cells/mm2.

Effect of Six-Month Postoperative Endothelial Cell Density on Graft Survival after Descemet Membrane Endothelial Keratoplasty

To analyze if 6-month endothelial cell density (ECD) affects long-term ECD outcome and graft survival 5 years after Descemet membrane endothelial keratoplasty (DMEK) in eyes with Fuchs endothelial corneal dystrophy (FECD). Retrospective cohort study. A total of 585 DMEK eyes were included. The study group was divided into 4 groups based on 6-month ECD quartiles: group 1 (n= 146) with 313 to 1245 cells/mm2, group 2 (n= 148) with 1246 to 1610 cells/mm2, group 3 (n= 145) with 1611 to 1938 cells/mm2, and group 4 (n= 146) with 1939 to 2760 cells/mm2. Group 1 was further split into subgroups 1a (n= 36) with 6-month ECD of ≤828 cells/mm2, 1b (n= 37) with 829 to 1023 cells/mm2, 1c (n= 37) with 1024 to 1140 cells/mm2, and 1d (n= 36) 1141 to 1245 cells/mm2. Descemet membrane endothelial keratoplasty. Long-term ECD, graft survival, and postoperative complication rates. For group 1, 6-month ECD decreased from 951 (±233) cells/mm2 (n= 146) to 735 (±216) cells/mm2 (n= 99) at 5 years postoperatively. Group 1 graft survival probability was 0.95 (95% confidence interval [CI], 0.91-0.99] at 5 years postoperatively, which was lower than for groups 2 to 4 (P= 0.001). Five-year graft survival in subgroup 1a was 0.79 (95% CI, 0.67-0.94), which was lower than in subgroups 1b to 1d (P= 0.001). Preoperative ECD did not influence graft survival (P= 0.400), and higher 6-month ECD values were associated with lower graft failure rates (hazard ratio, 0.994; 95% CI, 0.99-1.00; P= 0.001). Six-month ECD is associated with DMEK graft survival. High early cell loss after DMEK negatively affects long-term ECD outcome and graft survival. Grafts in the lowest 6-month ECD subgroup (≤828 cells/mm2) are at higher risk of failure within 5 years after DMEK. To ensure sufficiently high 6-month ECD, preoperative graft quality assessment should be optimized, and cellular stress induced to the graft should be minimized. Additionally, developing therapeutic options for the treatment of low postoperative ECD could further improve DMEK graft longevity.

Modified Technique for Scleral-Sutured Fixation with the Double Knots Technique for Posterior Chamber Intraocular Lens: Short-Term Observation

Purpose To evaluate the short-term safety and efficacy of a novel approach of utilizing the 9-0 looped polypropylene suture with double knots buried into the scleral groove and the scleral tunnel to minimize the risk of the suture erosion and suture knot exposure. Design Clinical-based retrospective study. Methods Records of consecutive patients who had anterior vitrectomy and scleral-fixated posterior chamber intraocular lens (IOL) implantation between July 2018 and April 2020 with a minimum follow-up of 3 months were reviewed. Results This study enrolled a total of 21 eyes from 20 patients (15 male). These patients had a mean age of 58.52 ± 8.55 years and were followed for an average of 1.08 ± 0.58 years postoperatively. Best-corrected visual acuity (BCVA) improved from a preoperative mean of 0.43 ± 0.41 logMAR to a significantly higher mean 3-month postoperative value of 0.09 ± 0.21 logMAR (Z = -3.35, p < 0.01). There were no statistical differences between the preoperative and postoperative corneal endothelial cell density (p=0.71). The postoperative complications included transient increased intraocular pressure in 5 eyes (24%). No other complications were detected during the follow-up. Conclusions The modified technique proposed is a safe, effective, and reliable approach resulting in good visual outcomes. Our procedure might have the potential benefit to avoid suture-related complications in scleral-fixated IOL implantation. Trial registration. Retrospective case series study, not applicable.