Yee RW, Matsuda M, Schultz RO, et al. Changes in the normal corneal endothelial cellular pattern as a function of age

Current Eye Research (Impact Factor: 1.64). 07/1985; 4(6):671-8. DOI: 10.3109/02713688509017661
Source: PubMed


Human endothelial morphologic changes were quantitated by specular microscopy and computer-assisted morphometry to establish normal baselines of various morphologic parameters. Cellular polymegethism and cellular pleomorphism increases with age, and normal baseline parameters are detailed. Furthermore, no significant difference in any morphologic parameters between the right and left eye and between central and peripheral endothelium was detected in the normal corneas examined. These normal morphologic baselines can possibly be utilized to detect early corneal endothelial pathology and/or cell loss nondetectable by cell density measurement.

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    • "The mean endothelial count (ECC) in the normal adult cornea ranges from 2000 to 2500 cells/mm2, and the count continues to decrease with age. Previous cross-sectional studies have shown the normal attrition rate of corneal endothelial cells is 0.3-0.5% per year.12 Morphological stability and functional integrity of the corneal endothelium are necessary to maintain long-term corneal transparency after cataract surgery. "
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    ABSTRACT: To compare the morphological (cell density, coefficient of variation and standard deviation) and functional (central corneal thickness) endothelial changes after phacoemulsification versus manual small-incision cataract surgery (MSICS). Prospective randomized control study. In this prospective randomized control study, patients were randomly allocated to undergo phacoemulsification (Group 1, n = 100) or MSICS (Group 2, n = 100) using a random number Table. The patients underwent complete ophthalmic evaluation and specular microscopy preoperatively and at 1and 6 weeks postoperatively. Functional and morphological endothelial evaluation was Noncon ROBO PACHY SP-9000 specular microscope. Phacoemulsification was performed, the chop technique and MSICS, by the viscoexpression technique. The mean difference in central corneal thickness at baseline and 1 week between Group 1 and Group 2 was statistically significant (P = 0.027). However, this difference at baseline when compared to 6 week and 1 week, 6 weeks was not statistically significant (P > 0.05). The difference in mean endothelial cell density between groups at 1 week and 6 weeks was statistically significant (P = 0.016). The mean coefficient of variation and mean standard deviation between groups were not statistically significant (P > 0.05, both comparisons). The central corneal thickness, coefficient of variation, and standard deviation were maintained in both groups indicating that the function and morphology of endothelial cells was not affected despite an initial reduction in endothelial cell number in MSICS. Thus, MSICS remains a safe option in the developing world.
    Middle East African journal of ophthalmology 03/2014; 21(1):56-60. DOI:10.4103/0974-9233.124098
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    • "This indicates that the surgery is more harmful to the endothelium probably due to more manipulation in the anterior chamber because of the floppy iris, use of iris hooks, etc. There were no significant differences in the percentage of hexagonal cells, CV or CCT, which implies equal and normal postoperative healing of the corneal endothelium in both study groups (Yee et al. 1985). This indicates that the higher cell loss in the tamsulosin group was not due to a toxic effect. "
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    ABSTRACT: Purpose: The purpose of this study was to assess the incidence of intraoperative floppy iris syndrome (IFIS) and the morphology of the corneal endothelium after cataract extraction in Caucasian male patients exposed to the α-1a adrenergic receptor antagonist tamsulosin. Methods: In a clinical prospective study, 23 male patients (23 eyes) treated with tamsulosin due to benign prostatic hyperplasia and 25 male patients (25 eyes) with no tamsulosin treatment had cataract surgery. The divide-and-conquer technique was used with the Infinity OZil(®) machine. A combination of Healon and Healon5 was used in all patients, but the use of additional Vision Blue, iris retractors or intracameral phenylephrine in the tamsulosin group was at the discretion of the surgeon. The endothelial cell density, variation in endothelial cell size (CV), percentage of hexagonal cells and central corneal thickness (CCT) were recorded at baseline and at 3 months postoperatively. Results: In the tamsulosin-treated group, 19 of 23 eyes (83%) developed IFIS, compared with no IFIS in the control group. Compared with the control group, the tamsulosin group showed significantly less dilatation at the start of the operation, significant miosis during surgery and significantly greater corneal endothelial cell loss 3 months postoperatively (12% versus 3%; p< 0.001). Conclusion: Intraoperative floppy iris syndrome during cataract surgery is significantly associated with tamsulosin-treated male patients. Patients on tamsulosin showed less preoperative dilatation, significant miosis during surgery, and had significantly greater postoperative endothelial cell loss compared with nontreated patients despite recommended precautions.
    Acta ophthalmologica 04/2013; 92(4). DOI:10.1111/aos.12140 · 2.84 Impact Factor
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    • "The healthy corneal endothelial cells of the human corneal endothelium are mostly hexagonal in shape [28, 29], and one of the morphological characteristic of isolated human corneal endothelial cells in vitro is the maintenance of the unique polygonal cellular structure in culture [8, 30, 31]. Cell circularity can be determined using the formula: Circularity = Perimeter2/(4π × Area), which quantifies the roundness of the cell assessed, where a value approaching 1.0 is equivalent to a cell with a cellular profile nearing circularity. "
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    ABSTRACT: The culture of human corneal endothelial cells (CECs) is critical for the development of suitable graft alternative on biodegradable material, specifically for endothelial keratoplasty, which can potentially alleviate the global shortage of transplant-grade donor corneas available. However, the propagation of slow proliferative CECs in vitro can be hindered by rapid growing stromal corneal fibroblasts (CSFs) that may be coisolated in some cases. The purpose of this study was to evaluate a strategy using magnetic cell separation (MACS) technique to deplete the contaminating CSFs from CEC cultures using antifibroblast magnetic microbeads. Separated "labeled" and "flow-through" cell fractions were collected separately, cultured, and morphologically assessed. Cells from the "flow-through" fraction displayed compact polygonal morphology and expressed Na(+)/K(+)ATPase indicative of corneal endothelial cells, whilst cells from the "labeled" fraction were mostly elongated and fibroblastic. A separation efficacy of 96.88% was observed. Hence, MACS technique can be useful in the depletion of contaminating CSFs from within a culture of CECs.
    International Journal of Biomaterials 01/2012; 2012:601302. DOI:10.1155/2012/601302
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