Coefficient Of Variation In Cell Size Research Articles

EFFECT OF MITOMYCIN C VERSUS BEVACIZUMAB ON CORNEAL ENDOTHELIAL CELLS FOLLOWING TRABECULECTOMY IN PRIMARY OPEN ANGLE GLAUCOMA

Background: Trabeculectomy is the standard treatment for patients with primary open angle glaucoma who had failed maximal tolerated medical therapy. The use of Mitomycin C (MMC) or Bevacizumab as adjuvant during trabeculectomy reduces fibrosis which in turn increases the possibility of success in filtrating surgery. However, MMC or Bevacizumab can lead to adverse effects, such as corneal toxicity especially on corneal endothelium, hypotony, formation of avascular cystic blebs, leaks, blebitis, and endophthalmitis. Objective: To evaluate and compare corneal endothelial cell changes before and after trabeculectomy with subconjunctival Mitomycin C versus trabeculectomy with sub conjunctival Bevacizumab in primary open angle glaucoma patients (1 month and 6 months postoperatively). Patients and methods: In this study, 20 patients (with 20 eyes) were divided into two equal groups: (Group A) included patients who underwent subscleral trabeculectomy with adjuvant intraoperative use of 0.2mg/ml MMC for 2 min, and (Group B) included patients who underwent subscleral trabeculectomy with subconjunctival injection of 1.25 mg/0.1 ml Bevacizumab. Non-contact specular microscope (Topcon sp-1p, Topcon Medical Inc., Japan) was done preoperatively, one month postoperatively and six months post-operatively to assess the corneal endothelium as regard ECD (cells/mm²), CV in cell size, HEX and CCT. This prospective comparative study was done at Department of ophthalmology, Sayed Galal University Hospital, Cairo, Egypt, and it was carried out from February 1ˢ 2019 to October 30 2020. Results: Six males (60%) and four females (40%) in group A while five males (50%) and five females (50%) in group B. The patients’ ages ranged from {25 to 47 years} (mean age35.70±6.70) in group A, and ranged from {20 to 45 years} (mean age 31.20±8.70) in group B. MMC and Bevacizumab did not have the same effect on corneal endothelium. There was a significant decrease in endothelial cell density (ECD) after six months post-operatively in both groups with significant difference between the two groups, and insignificant increase in central corneal thickness (CCT) after six months post-operatively in both groups, Also there was a significant changes in coefficient of variation (CV), and percentage of hexagonal cells (HEX), an increase in CV (polymegathism), and decrease in hexagonality (pleomorphism) in both groups, with significant difference between the two groups. Conclusion: MMC affected all parameters of endothelial cells more than Bevacizumab.

Yaşlanmanın Kornea Endotel Hücre Özellikleri Üzerine Etkisinin Değerlendirilmesi

Objective: To describe the corneal endothelial cell density and morphology in normal adult eyes, and determine the influence of aging on these parameters. Material and Methods: In this cross-sectional study, specular microscopy was performed in 547 eyes of 547 healthy volunteers aged 20 to 85 years. Of these, 279 were female, and 268 were male. The study parameters included endothelial cell density (ECD), cell area (CA), the coefficient of variation (CoV) and percentage of hexagonal cells (Hex%). The influence of age and gender on these parameters were evaluated. Results: The mean ECD and mean CA in the study population were 2607±323 cells/mm2 and 389.6±51.2 μm2, respectively. In the correlation analysis, there was a decrease in mean ECD (r= - 0.305, p<0.001), and an increase in mean CA (r=0.295, p<0.001) with increasing age. The mean CoV in cell size and the mean Hex% were 35.7±6.06% and 56.8±9.1%, respectively. There was a weak correlation between increasing age and CoV in cell size (r=0.075, p=0.021), and the percentage of hexagonal was not correlated with age (p=0.088). There were no statistically significant differences in mean ECD, mean CoV in cell size, or hexagonality between genders (all p values>0.05). Conclusion: Our data for the corneal endothelial structure in Turkish population showed that age but not gender, has a negative impact on endothelial cell density. Age was not a determinant in the pleomorphic changes of the endothelium.

Corneal endothelial cell density in healthy Caucasian population

AimTo reveal the changes of corneal endothelial characteristics with aging among Caucasian population. MethodsNon-contact specular microscopy was performed in 564 eyes of 282 healthy Caucasian Turkish patients. Endothelial cell density (MCD), mean cell area (MCA), coefficient of variation (CV) in cell size, percentage of hexagonal cells, and central corneal thickness (CCT) were measured. ResultsThe mean age was 42±17.1 (6–85) years. The MCD of the population was 2732±305cell/mm2 (range, 1904–3802cell/mm2). The MCA was 368±41m2 (range, 263–522m2). The mean CV in cell size was 34±7 (range, 25–68), the mean percentage of hexagonal cells was 46±8% (range, 25–76%), and CCT was 513±39 (range, 407–623). There was statistically significantly negative correlation (p<0.05) between age and cell density, hexagonality, and pachymetry. There was statistically significant correlation (p<0.05) between age and MCA. ConclusionWe report the normal values of corneal endothelial characteristics in Caucasian Turkish eyes. Over the age of 20, the MCD of Caucasian eyes is more than the Indian and Iranian eyes and less than the Chinese eyes. Caucasian population’s cell density in under the age of 20 is 3101±268cell/mm2.

Corneal Endothelial Cell Density and Morphology in Healthy Turkish Eyes

Purpose. To describe the normative values of corneal endothelial cell density, morphology, and central corneal thickness in healthy Turkish eyes. Methods. Specular microscopy was performed in 252 eyes of 126 healthy volunteers (M : F, 42 : 84). Parameters studied included mean endothelial cell density (MCD), mean cell area (MCA), coefficient of variation (CV) in cell size, percentage of hexagonal cells, and central corneal thickness (CCT). Results. The mean age of volunteers was 44.3 ± 13.5 (range, 20 to 70) years. There was a statistically significant decrease in MCD (P < 0.001; correlation, −0.388) and percentage of hexagonal cells, (P < 0.001; correlation, −0.199) with age. There was also a statistically significant increase in MCA (P < 0.001; correlation, 0.363) with increasing age. There was no statistically significant difference in MCD, MCA, CV in cell size, percentage of hexagonal cells, and CCT between genders and there was also no significant difference in these parameters between fellow eyes of subjects. Conclusions. Normotive data for the endothelium in the Turkish population are reported. Endothelial cell density in the Turkish eyes is less than that described in the Japanese, American, Chinese, and Filipino eyes and higher than that described in Indian, Thai, and Iranian eyes.

Morphometric changes of corneal endothelial cells in pseudoexfoliation syndrome and pseudoexfoliation glaucoma

ObjectiveTo evaluate the corneal endothelial morphometry and central corneal thickness (CCT) in pseudoexfoliative (PEX) eyes with and without glaucoma and to compare with normal eyes and eyes with primary open-angle glaucoma (POAG). MethodA total of 166 patients were included in this study: 36 eyes with pseudoexfoliation syndrome (PXS), 30 eyes with pseudoexfoliation glaucoma (PXG), 40 eyes with POAG, and 60 normal eyes. Corneal endothelial cell density (ECD), coefficient of variation (CV) in cell size, and percentage of hexagonal cells were measured using a non-contact specular microscope, whereas CCT was measured with an ultrasonic pachymeter. ResultsECD and percentage of hexagonal cells were lower in PEX groups and in the POAG group compared with normal eyes, while the CV in cell size was greater. There was a tendency for greater cell loss and morphological abnormalities of the corneal endothelial cells in PXG eyes compared to PXS eyes, when all pseudoexfoliative eyes were analyzed together. Changes in endothelial cells increased with age. There were no significant differences in mean CCT between the four groups. ConclusionEndothelial cell density is significantly decreased, and pleomorphism and polymegathism of cells are increased in PEX eyes, particularly when intraocular pressure is high.

Cambios morfométricos de las células del endotelio corneal en el síndrome pseudoexfoliativo y glaucoma pseudoexfoliativo

ObjetiveTo evaluate the corneal endothelial morphometry and central corneal thickness (CCT) in pseudoexfoliative (PEX) eyes with and without glaucoma and to compare with normal eyes and eyes with primary open-angle glaucoma (POAG). MethodA total of 166 patients were included in this study: 36 eyes with pseudoexfoliation syndrome (PXS), 30 eyes with pseudoexfoliation glaucoma (PXG), 40 eyes with POAG, and 60 normal eyes. Corneal endothelial cell density (ECD), coefficient of variation (CV) in cell size, and percentage of hexagonal cells, were measured using a non-contact specular microscope, whereas CCT was measured with an ultrasonic pachymeter. ResultsECD and percentage of hexagonal cells were lower in PEX groups and in the POAG group compared with normal eyes, while the CV in cell size was greater. There was a tendency for greater cell loss and morphological abnormalities of the corneal endothelial cells in PXG eyes compared to PXS eyes, when all pseudoexfoliative eyes were analyzed together. Changes in endothelial cells increased with age. There were no significant differences in mean CCT between the four groups. ConclusionEndothelial cell density is significantly decreased, and pleomorphism and polymegathism of cells are increased in PEX eyes, particularly when intraocular pressure is high.