Difference In Endothelial Cell Counts Research Articles

Corneal endothelial changes seven years after phacoemulsification cataract surgery

PurposeTo evaluate long-term postoperative corneal changes after phacoemulsification cataract surgery.MethodsTwenty patients who participated in a previous study regarding corneal endothelial changes after phacoemulsification cataract surgery were examined after 7 years. The patients were divided in three groups based on their initial increase in central corneal thickness day one after the surgery: < 5% increase, 6–20% increase and ≥ 20% increase. The primary outcome measures were corneal endothelial cell loss (ECL), endothelial cell count (ECC) and endothelial morphology.ResultsAfter 7 years, a difference in cell loss between the groups was observed, except for groups 1 and 2. Endothelial cell count (ECC) differed significantly between groups 1 and 3 at 3 months. At 7 years, there was no difference in ECC between the three groups. Cell loss was found exclusively in group 1 between 3 months and 7 years. Endothelial cell morphology showed a converging pattern between 3 months and 7 years.ConclusionAfter phacoemulsification cataract surgery, long-term ECC and morphology appear to converge towards a comparable steady state regardless of initial corneal swelling and endothelial cell loss.

Effect of Body Refrigeration Time on Cornea Donor Tissue.

To determine how early body refrigeration affects corneal donor transplant suitability and endothelial cell density. Donor information was obtained from the CorneaGen Eye Bank including demographics, time of death to preservation, and body refrigeration status, for donors between 2012 and 2016. The death to preservation interval was classified into 3 categories: 0 to 10, 10 to 20, and 20+ hours. Two primary logistic method models were fit using a main effects model and an interaction model to determine the association of body refrigeration on unsuitability of transplantation and endothelial cell density. Analysis was from 42,929 donor eyes, with a mean (standard deviation) endothelial cell count of 2743 (415) cells/mm2. Fifty-nine percent of donor eyes were from male donors in the eye bank data set, and the mean death to preservation interval was 11.0 (5.6) hours for all eyes. Unsuitability for transplantation demonstrated a reduced adjusted odds ratio by 22% (OR = 0.78, P = 0.009) when the body was refrigerated during the death to preservation interval versus when the body was not refrigerated. Eyes that were refrigerated, however, exhibited no statistically significant difference in endothelial cell count from eyes that were not refrigerated (P = 0.12). We demonstrate an appreciable effect of early body refrigeration on transplant suitability in this large cohort of eye bank eyes. There was no beneficial effect of body refrigeration on endothelial cell count.

Scleral Fixation of Single-Piece Foldable IOL Using Double-Flanged Technique.

PurposeTo describe the efficiency and visual results of a new method of transconjunctival intrascleral fixation of single-piece foldable IOL using double-flanged 6/0 prolene suture.Materials and MethodsSeventeen aphakic eyes of 17 patients without adequate capsular support were involved in this study. Lens was prepared by passing the 6/0 prolene suture in a track in the haptic of single-piece foldable IOL created by 31 g needle. The 6/0 prolene suture was retrieved through a 30 g needle transconjunctivally to outside the globe; then, IOL was implanted and a terminal bulb was created at the outer end of the prolene suture.ResultsAll cases were aphakic after complicated phacoemulsification. In 10 cases hydrophilic IOLs were used and in 7 cases hydrophobic IOLs were used. There is clear statistically significant difference between pre-UCVA and post- UCVA. Complications included suture slippage in 2 cases and prolene bulb exposure in one case. There was no significant difference in endothelial cell count and IOP before and after 3 months.ConclusionTransconjunctival intrascleral fixation of foldable single-piece IOLs is a safe efficient method for correcting aphakia.

Endothelial Safety and Efficacy of Ex Vivo Collagen Cross-linking of Human Corneal Transplants

To assess endothelial safety and efficacy of exvivo corneal collagen cross-linking (CXL) in human corneal transplants stored in 2 different culture media. Fellow-eye controlled laboratory study of exvivo human donor corneas. Three sets of paired human donor corneas, 5 pairs each, were stored in organ culture medium before deswelling either at 31 C or at room temperature. One eye of each pair was cross-linked by 0.1% riboflavin in hydroxylpropyl methylcellulose (HPMC) instillation for 10minutes followed by 10minutes of ultraviolet-A (9 mW/cm2) irradiation while contralateral eyes served as controls. In Set 1, endothelial cell densities were determined. In Set 2, paired samples were assigned to the 2 deswelling media and CXL efficacy was assessed comparing to untreated controls using collagenase-A-assisted enzymatic digestion. In Set 3, biomechanical testing was performed in the eye pairs (treated vs control) by stress/strain measurements. There was no difference in endothelial cell counts between CXL samples and controls (P= .21). No statistically significant difference in digestion dynamics was found between tissues stored in the 2 different culture media. Complete enzymatic digestion was slowed down by 3 hours in the cross-linked samples (P= .036). Stress needed for a 12% strain was increased by 34% in the treatment group compared to control (P= .04). Exvivo CXL of human donor tissue is an effective and safe procedure with no difference regarding efficacy between 2 commercially available deswelling media. Biochemical and biomechanical resistance were significantly increased after CXL. Patients requiring keratoplasty owing to corneal melting might benefit from the strengthening effect of preoperative CXL of donor tissue.

Comparative study of safety and efficacy of dispersive versus cohesive ophthalmic viscosurgical devices in cataract surgery after phacoemulsification

Background: To compare efficacy and safety of dispersive versus cohesive ophthalmic viscosurgical devices in cataract surgery after phacoemulsification to prevent endothelial cell loss. Material and Method: Total 40 consecutive patients of senile cataract with hard nucleus (grade 3/4) who attended AVBRH eye Opd were selected. 40 cases were randomly divided in two groups depending on the use of two different OVD's as – Group 1 Dispersive (20 cases): Hydroxypropyl methylcellulose (2 %), Group 2 Cohesive (20 cases): Sodium hyaluronate (1.4%). Preoperative examination and evaluation of BCVA, corneal thickness by pachymetry and endothelial cell count by specular microscope was done. ECCE with PCIOL implantation by phacoemulsification was performed by a single surgeon. Postoperative all the parameters were recorded on day 1, 1 week, 1 month and 3 months using the same methods and instruments. Results: In our study there was no significant change was seen preoperatively in age, visual acuity, intraocular pressure, and endothelial cell count among the two groups. Postoperatively rise in IOP was seen in both groups i.e. 30 % in group A and 10 % in group B, corneal endothelial cell loss was seen in both groups after performing phacoemulsification, there was no significant difference in the change in cornea thickness in eyes among two groups (P=0.20). Conclusion: Our study shows no significant difference in endothelial cell count and corneal thickness in eyes between two groups.

Comparison of the performance and safety of 2 ophthalmic viscosurgical devices in cataract surgery

To compare the clinical performance and safety of 2 ophthalmic viscosurgical devices (OVDs)-Twinvisc (OVD 1) and Duovisc (OVD 2)-in cataract surgery. European multicenter study. Prospective randomized controlled study. Patients with cataract had phacoemulsification and intraocular lens implantation in 1 eye. They were randomly assigned to receive OVD 1 or OVD 2. Preoperative and postoperative examinations over 3months included mean intraocular pressure(IOP), incidence of IOP peaks (≥30mm Hg and ≥24mm Hg), endothelial cell count (ECC), corneal thickness, and intraocular inflammation. A subjective evaluation of the OVDs was performed. The study comprised 220 patients. The incidence of IOP peaks and the mean IOP were not statistically significantly different between the 2 groups at any of the follow-up visits. At 6hours, the incidence of IOP spikes 30mm Hg or higher was 6.5% and 7.2% in the OVD 1 and the OVD 2 groups, respectively (P=.846). For the IOP spikes 24mm Hg or higher, the incidence was 16.8% and 25.2%, respectively (P=.128). Three months postoperatively there was no statistically significant difference in ECC and pachymetry between the 2 groups. Mild inflammation was noticed up to 7days postoperatively after which it resolved in both groups. Subjectively, the OVD 2 was easier to use, whereas the OVD 1 had better cohesive and dispersive properties. Both OVDs have similar performance and safety profiles in phacoemulsification cataract surgery. No clinically relevant differences were found between the 2 devices regarding transient IOP spikes, mean IOP, corneal endothelium injury, or inflammation.

Comparison of endothelial cell loss and complications between phacoemulsification and manual small incision cataract surgery (SICS) in uveitic cataract.

Endothelial cell loss and complications after cataract surgery may be higher when cataract is complicated by uveitis. To compare endothelial cell damage and complication rates after phacoemulsification and manual small incision cataract surgery (SICS) in patients with uveitis. Patients with uveitic cataract were randomly allocated for phacoemulsification (n=75) or manual SICS (n=80) in a double blind prospective study. In the bag implantation of a hydrophobic acrylic intraocular lens was aimed in all cases. Patients with follow up of less than six months were excluded. Main outcome measures were alteration in endothelial cell counts (ECC) and morphology, improvement in vision and complication rates. ECC was measured preoperatively and at 1 week, 3 months and six months, postoperatively. Six patients were lost to follow up and another three due inability to implant IOL. There were no significant difference in endothelial cell counts (P= 0.032), the variance of endothelial cell size (CV) and percentage of hexagonal cells between both the groups at six months (Mann-Whitney test, P=0.283). Endothelial cell density was significantly less in the group in which vitrectomy and/or pupil dilatation procedures were performed (2290±31.5 cells/mm2) versus (2385±50.3 cells/mm2), respectively (t test, P less than0.001). Incidence of postoperative complications that were observed like persistent uveitis (P=0.591), macular edema (P=0.671) and PCO (P=0.678) and visual outcome (P=0.974) were comparable between the two groups. Manual SICS and phacoemulsification do not differ significantly in endothelial cell loss and complication rates in uveitic eyes. However, increased anterior chamber manoeuvring due to additional procedures may lead to significantly higher endothelial cell loss.

The effect and safety of intravitreal injection of ranibizumab and bevacizumab on the corneal endothelium in the treatment of diabetic macular edema

Objective: To investigate the effect and safety of intravitreal injection (IVI) of bevacizumab and ranibizumab on corneal endothelial cell count and morphology in patients with diabetic macular edema.Materials and methods: A total of 60 eyes from 60 consecutive patients who received 0.5 mg/0.05 ml IVIs of bevacizumab (n = 30, IVB group) or 1.25 mg/0.05 ml ranibizumab (n = 30, IVR group) for three consecutive months were investigated prospectively. Specular microscopy was performed to evaluate endothelial cell count, the percentage of hexagonal cells (pleomorphism), and the coefficient of variation of the cell size (polymegathism); optical biometry was performed to evaluate central corneal thickness. Results before injection and 1 month after the first and third injections were compared.Results: The groups were matched for age (p = 0.11) and gender (p = 0.32). There was no significant difference in endothelial cell count (IVB group, p = 0.66; IVR group, p = 0.74), pleomorphism (IVB group, p = 0.44; IVR group, p = 0.88) and polymegathism (IVB group, p = 0.21; IVR group, p = 0.24) before injection or 1 month after the first and third injections. There was also no difference in central corneal thickness (IVB group, p = 0.15; IVR group, p = 0.58) before injection or 1 month after the first and third injections.Conclusion: Monthly 1.25 mg/0.05 ml IVIs of bevacizumab or 0.5 mg/0.05 ml of ranibizumab for three consecutive months in the treatment of diabetic macular edema does not affect corneal morphology and has no harmful effects on the endothelium.

Toxicity of intrastromal voriconazole injection on corneal endothelium in rabbits.

The aim of this study was to evaluate the toxicity of intrastromally injected voriconazole on corneal endothelial cells in rabbits. In total, 32 eyes of 16 rabbits (8 eyes for each group) were divided into 4 groups according to the concentration of voriconazole [group A: 50 μg/0.1 mL (0.05%), group B: 100 μg/0.1 mL (0.1%), group C: 250 μg/0.1 mL (0.25%), or group D: 500 μg/0.1 mL (0.5%)]. Right eyes were injected intrastromally with voriconazole at concentrations of 50 μg/0.1 mL, 100 μg/0.1 mL, 250 μg/0.1 mL, or 500 μg/0.1 mL. Left eyes were injected intrastromally with isotonic saline as controls. Central corneal thickness and endothelial cell counts were measured before and at 6 hours, 1 day, and 1 week after the injection was given. Corneas were then harvested for transmission electron microscopy. Only the 0.5% group did not significantly recover from corneal edema 1 week after the injection (P = 0.167, P = 0.051, P = 0.086, P = 0.001 in groups A-D, respectively). There were significant differences in endothelial cell counts for the 0.1% and 0.25% groups (P = 0.077, P = 0.019, P = 0.008 in groups A-C, respectively). Transmission electron microscopy evaluation revealed definite necrotic changes in endothelial cells at concentrations of 0.1%, 0.25%, and 0.5%, but only microstructural changes at a concentration of 0.05%. Our results suggest that voriconazole could be injected safely into the intrastromal layer at a concentration of 0.05% with low endothelial cell toxicity. However, injections should be administered with caution because of the risk of microstructural damage.

Combined topical and intracameral anesthesia for Descemet’s stripping automated endothelial keratoplasty

To evaluate the use of combined topical and intracameral anesthesia for Descemet's stripping automated keratoplasty (DSAEK). This was a retrospective comparative cohort analysis consisting of 10 eyes in 10 consecutive patients undergoing DSAEK surgery with combined topical and intracameral anesthesia. These cases were compared with 21 randomly selected controls during the same time period undergoing DSAEK surgery performed under retrobulbar anesthesia. Incidence of intraoperative and postoperative complications, and endothelial cell counts were compared. In all cases, DSAEK was completed without intraoperative complications. All patients tolerated the procedure well. There were 6 cases of postoperative graft dislocation requiring rebubbling, and no cases of primary failure or endophthalmitis. No significant difference in endothelial cell counts was found at final follow-up. Short-term results suggest that combined topical and intracameral anesthesia is as safe and effective for DSAEK in cooperative patients when compared to retrobulbar anesthesia. It may thereby be an alternative anesthetic modality for patients in whom retrobulbar or peribulbar anesthesia may be risky or contraindicated.

Toxicity of voriconazole on corneal endothelial cells in an animal model

AimsTo determine the effect of intracamerally injected voriconazole on corneal endothelial cells in rabbit eyes.MethodsVarious concentrations of voriconazole (0%, 0.03%, 0.1%, 0.25%, 0.5% and 1%) were injected intracamerally in 36...

Suture-Assisted vs Forceps-Assisted Insertion of the Donor Lenticula during Descemet Stripping Automated Endothelial Keratoplasty

To compare a new insertion method using a suture with the standard forceps-assisted insertion of the lamellar corneal graft in Descemet stripping automated endothelial keratoplasty (DSAEK). Interventional, comparative case series. DSAEK was performed on 28 consecutive eyes of 28 patients (mean age +/- standard deviation, 72.5 +/- 9.7 years; 12 males). The donor tissue was prepared using the Moria automated lamellar therapeutic keratectomy microkeratome head with a 300-mm blade depth on a Moria artificial anterior chamber (Moria, Antony, France). The central 9 mm of the recipient's Descemet membrane were stripped through a superior limbal incision. In eight consecutive unselected patients, a 10-0 monofilament suture on a long straight needle was used to insert the folded donor lenticula into the recipient's eye, whereas in the other 20 patients, a standard insertion forceps was used. During the suture insertion, an anterior chamber maintainer was used to fill the anterior chamber continuously with balanced salt solution to prevent its collapse. Suture-assisted DSAEK did not differ significantly from forceps-assisted DSAEK in any of the preoperative parameters. No significant differences were noted in the intraoperative or postoperative complications. Six months after surgery, there were no significant differences in endothelial cell counts (1804 vs 1935 cells/mm(2), respectively), visual acuity (20/40 vs 20/36, respectively), or refraction (spherical equivalent, 0.93 vs 1.05 diopters, respectively). Suture-assisted DSAEK is a valid alternative to forceps insertion; however, it does not seem to offer a significant advantage.

Intracameral triamcinolone acetonide to control postoperative inflammation following cataract surgery with phacoemulsification

To explore the efficacy, safety and tolerability of 1 mg intracameral triamcinolone acetonide (TA) in controlling ocular inflammation in patients undergoing cataract surgery. Sixty eyes of 60 patients undergoing cataract extraction with phacoemulsification at the Department of Ophthalmology, Baskent University School of Medicine were randomized into two groups. After surgery, eyes in group A were injected with 1 mg/0.1 ml TA into the anterior chamber, but eyes in group B were not. Postoperatively; in group B, topical prednisolone acetate 1% eyedrops were administered six times per day for 7 days, then four times per day for 15 days, to control postoperative inflammation. In group A, topical corticosteroids were not used. To evaluate the efficacy of intracameral TA, anterior chamber cells, anterior chamber flare and conjunctival hyperaemia were measured on postoperative days 1, 7 and 30 by slit-lamp biomicroscopy. The safety of intracameral TA was evaluated by visual acuity measurements, intraocular pressure values and fundus examination. Tolerance variables were assessed by the degree of burning, stinging and blurred vision. Both treatments were equally effective in controlling postoperative inflammation following phacoemulsification. No statistically significant differences between groups were observed for the efficacy, safety and tolerance variables, and no serious adverse events were observed. Intracameral TA of 1 mg can effectively be used to control postoperative inflammation after uncomplicated cataract surgery with phacoemulsification. This makes it possible to decrease the dosage and duration of topical prednisolone acetate.

Endothelial cell growth on silicon modified hydrogenated amorphous carbon thin films

The biological response of human microvascular endothelial cells (HMEC-1) seeded on Si-DLC films and on control surfaces was evaluated in terms of initial cell enhancement, growth, and cytotoxicity. The microstructure of the films was characterised by Raman spectroscopy and X-ray photoelectron spectroscopy. The effect of changes in microstructure, surface energy, surface electronic state, and electronic conduction, on the biological response of the films to endothelial cells was investigated. Endothelial cell adhesion and growth was found to be affected by changes in the microstructure of the films induced by silicon doping and thermal annealing. We observed a significant statistical difference in endothelial cell count between the as-deposited DLC and Si-DLC films using the one sample t-test at a p-value of 0.05. We also found a statistically significant difference between the adhesion of HMEC films on DLC and Si-DLC films at various annealing temperatures using the one-way ANOVA F statistic test at p < 0.05 and the post-hoc Tukey test. One sample t-test at p < 0.05 of MTT-assay results showed the endothelial cells to be viable when seeded on DLC/Si-DLC films. We suspect that the increased adhesion of endothelial cells induced by increasing the amount of silicon in the Si-DLC films is associated with the development of a suitable surface energy due to silicon addition, which neither favored cell denaturing nor preferential water spreading before cellular attachment on the film surface. The presence of an external positively charged dipole on the Si-DLC films confirmed by our Kelvin probe measurements is also expected to enhance the adhesion of endothelial cells that are well known to carry a negative charge. The Si-DLC films investigated hold potential promise as coatings for haemocompatible artificial implants.

Effect of mitomycin-C on the corneal endothelium during excimer laser surface ablation

To study the effects of mitomycin-C (MMC) on the corneal endothelium after surface ablation. This prospective observer-masked study comprised 40 consecutive patients (80 eyes) scheduled to have laser-assisted subepithelial keratectomy (LASEK) to correct myopia. The patients were divided into 2 groups. Group 1 included 32 eyes in which the ablation depth was 50 mum or less and that received no MMC. Group 2 included 48 eyes in which the ablation depth exceeded 50 mum and were treated with intraoperative MMC 0.02% for 30 seconds over the ablated zone. Preoperatively and 3 months postoperatively, 3 photographs of the central cornea of each eye were obtained using specular microscopy. A masked observer evaluated the endothelial cell density and compared the results between groups and the preoperative versus the postoperative results within the same group. The mean patient age was 31.5 years +/- 4.6 (SD) in Group 1 and 33.2 +/- 7.9 years in Group 2 (P = .3). Within-group comparison between the preoperative and postoperative endothelial cell density values showed a statistically significant increase in both groups. The mean values in Group 1 were 2462.5 +/- 226.8 cells/mm(2) preoperatively and 2562.5 +/- 258.7 cells/mm(2) postoperatively (P = .0001). The means in Group 2 were 2466.6 +/- 294.1 cells/mm(2) and 2525 +/- 312.5 cells/mm(2), respectively (P = .0008). The differences in endothelial cell counts between Group 1 and Group 2 preoperatively and postoperatively were not statistically significant (P = .9 and P =.5, respectively). A single intraoperative application of MMC 0.02% for 30 seconds after laser surface ablation did not seem to cause a substantial change in corneal endothelial cell density.

Intraoperative Mitomycin and Corneal Endothelium After Photorefractive Keratectomy

To determine whether there is an increased risk to the corneal endothelium when mitomycin C (MMC) is administered after photorefractive keratectomy (PRK). Prospective, randomized, double-blind, placebo-controlled crossover trial. Corneal endothelium was analyzed preoperatively and postoperatively in 18 eyes of nine patients who were administered either MMC- or balanced salt solution (BSS)-supplemented PRK at Codet Aris Vision, Tijuana, Mexico. After laser ablation, one eye was randomly assigned to intraoperative topical MMC 0.02% treatment for 30 seconds, and the fellow eye (the control eye) was treated in a standard fashion with topical BSS. Preoperative pachymetry and endothelial cell count were performed and compared with postoperative measurements after one month and three months. Main outcome measure studied was endothelial cell loss. There was no significant difference in the preoperative endothelial cell count between the 2 groups: MMC group 2835 +/- 395, control group 2779 +/- 492, P = .62. In the control group, at one month and three months the difference in the endothelial cell count was not statistically significant (P = .27, P = .14, respectively). However, in the MMC group the endothelial cell loss was statistically significant: at one month 14.7 +/- 5.1%, and at three months 18.2 +/- 9.0% (P = .0006, P = .002, respectively). The use of intraoperative topical MMC 0.02% for 30 seconds after PRK may affect the endothelial cell count.

Corneal endothelial cell protection with a dispersive viscoelastic material and an irrigating solution during phacoemulsification: low-cost versus expensive combination

Purpose To evaluate the protective effect on corneal endothelial cells of a low-cost and an expensive combination of a dispersive viscoelastic material and an irrigating solution during phacoemulsification. Setting Department of Ophthalmology, University of Vienna, Vienna, Austria. Methods This prospective randomized examiner- and patient-masked study comprised 90 eyes of 45 consecutive patients with age-related cataract in both eyes. For each patient, the first eye was randomly assigned to receive hydroxypropyl methylcellulose 2% (Ocucoat ®) and Ringer’s solution (low-cost combination) or sodium chondroitin sulfate 4%–sodium hyaluronate 3% (Viscoat ®) and an enriched balanced salt solution (BSS Plus ®) (expensive combination) during phacoemulsification. The contralateral eye received the other treatment. Endothelial cell function was evaluated by measuring corneal thickness (CT) using partial coherence interferometry, morphology assessment, and endothelial cell counts. Results The acute postoperative increase in CT was +9.8 μm in the low-cost group and +10.9 μm in the expensive group; the difference between groups was not significant. After 1 month, the CT still differed significantly from baseline in the low-cost group. Three months after surgery, the CT had returned to baseline values in both groups. There was no significant between–group difference in endothelial cell counts or morphology. Conclusions During phacoemulsification in a nonselected patient population, there was no difference in acute postoperative corneal edema and endothelial cell morphology after 3 months between a Viscoat and BSS Plus combination and an Ocucoat and Ringer’s solution combination. Eyes receiving the expensive combination had marginally faster recovery of corneal swelling by 3 months. However, the cost of Viscoat and 500 mL BSS Plus is 5 times that of Ocucoat and Ringer’s solution.