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Background: Primary open angle glaucoma is an irreversible disease causing a reduction in corneal endothelium cells mainlyresponsible for corneal clarity along withnerve fiber layer loss.ObjectiveiTo calculate loss of corneal endothelium density (CED) andretinalnerve fiber layer(RNFL) thickness in Primary openangle glaucoma(POAG).Material and Methods: It was a prospective observational study conducted in Khyber Teaching Hospital from April 2015 toDecember 2019. A total of 112 patients were included in the study through consecutive non-probability sampling technique.Patients were diagnosed with open angle glaucoma on the basis of intra ocular pressure (IOP), optic disc changes, visual fieldschanges and Optical coherence tomography (OCT) findings. Corneal endothelium density and thickness of retinalnerve fiber layerwas calculated onthe basis of specular microscopy and OCT. These were compared with normalmatched values.Results: The POAG patients have average 17.12% CED and 34.73% RNFLthickness loss.Conclusion:It is observed that Corneal endothelial cell count may be evaluated along with nerve fiber layer thickness in Primaryopen angle glaucoma.Keywords.Specular microscopy, OCT, RNFL,POAG.

Purpose: To characterise the anatomical parameters of the porcine eye for potentially using it as a laboratory model of dry eye. Methods: Anterior chamber depth and angle, corneal curvature, shortest and longest diameter, endothelial cell density, and pachymetry were measured in sixty freshly enucleated porcine eyeballs. Results: Corneal steepest meridian was 7.85 ± 0.32 mm, corneal flattest meridian was 8.28 ± 0.32 mm, shortest corneal diameter was 12.69 ± 0.58 mm, longest corneal diameter was 14.88 ± 0.66 mm and central corneal ultrasonic pachymetry was 1009 ± 1 μm. Anterior chamber angle was 28.83 ± 4.16°, anterior chamber depth was 1.77 ± 0.27 mm, and central corneal thickness measured using OCT was 1248 ± 144 μm. Corneal endothelial cell density was 3250 ± 172 cells/mm2. Conclusions: Combining different clinical techniques produced a pool of reproducible data on the porcine eye anatomy, which can be used by researchers to assess the viability of using the porcine eye as an in-vitro/ex-vivo model for dry eye. Due to the similar morphology with the human eye, porcine eyeballs may represent a useful and cost effective model to individually study important key factors in the development of dry eye, such as environmental and mechanical stresses.

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

• Seventy-six patients who had undergone unilateral phacoemulsification of cataracts had their endothelial cell density (ECD) measured by specular microscopy. When compared with the unoperated contralateral eye, there was a mean decrease in ECD of 33.8%. Ten patients who had undergone unilateral intracapsular cataract extraction had a mean decrease in ECD of 14.9%. Cataract extraction by phacoemulsification appears to be more traumatic to the corneal endothelium than is intracapsular extraction.

Corneal endothelial cell density was measured in normal subjects and in a group of monozygotic and dizygotic twins. Cell density was found to decline with age and to be similar in right and left eyes in normal subjects. Both monozygotic and dizygotic twins were found to have very similar mean endothelial cells densities and particularly so in like-sided eyes.

An original system of grading of the corneal endothelial specular reflection, as assessed with a Haag-Streit 900 slit-lamp biomicroscope, has been shown to have a very highly significant relation to the endothelial cell density measured by contact specular photomicroscopy. The grading, though subjective and therefore not a substitute for the detailed record of photomicroscopy, is readily applicable to clinical practice and is a useful method of comparing and recording endothelial cell densities when assessed by the same observer. The intraobserver, but not the interobserver, variability has been examined, and the theoretical aspects of the grading system and a clinically applicable interpretation of the grading are presented.

Serial endothelial photographs were taken preoperatively and postoperatively in 200 eyes; 111 eyes contained a Rayner iris clip lens, 54 eyes contained a Fyodorov Sputnik lens, and 35 eyes had no lens. Central endothelial cell density was changed in all instances, with counts in implanted eyes declining 25 to 30%, and in nonimplanted eyes 10 to 15%. In both instances, the decline essentially ceased at about three months. The cause of the greater decline in implanted eyes appeared to be mechanical and subsequent cell loss after the 90-day period was virtually equal for the two groups. Methods that may be used to alter the difference in cell density occurring with implantation are best analyzed by using the 90-day period data for comparison.

• A new technique for determining corneal endothelial cell density from specular photomicrographs has been devised. The method is simple, inexpensive, and provides a high degree of accuracy and reproducibility.

Central corneal endothelial photographs were taken with a specular microscope. The cell density was calculated with a computerized image analyzer. No difference between the treated and control eyes could be found. The laser energy level delivered in trabeculoplasty seems to be too small to induce any permanent changes in the endothelial cells.

The central corneal endothelium of a consecutive group of 158 patients with senile cataract was examined before intracapsular cataract extraction with implantation of an open-loop anterior chamber lens and 6, 12 and 48 months after surgery. Corneal endothelial morphometry was performed using an automated digital image analysis system. After 6 months of follow-up, there was an average loss of 10.8% in central corneal endothelial cell density, which increased to 14.8% after 12 months and 18.8% after 48 months. The early post-operative endothelial cell loss was correlated significantly with a decrease of cell pattern stability and polymegathism (P less than 0.0001). There was also a significant correlation between the continuous post-operative cell loss and the simultaneous changes of pattern stability and polymegathism and the age at the time of surgery (P less than 0.05).

The corneal endothelial cells of 25 patients with unilateral acute glaucoma were photographed with a clinical specular microscope. Photography was performed as soon as (average 6-12 h) the IOP had been lowered with iv Acetazolamide and/or Mannitol and topical Pilocarpine therapy, and the corneas had become clear. Peripheral iridectomy was performed on the affected eye and prophylactically on the fellow eye in most of these patients. The follow-up endothelial photographs were taken 6-24 months postoperatively. High intraocular pressure lasting 3 days or more lowered the central endothelial cell density. But a rise in pressure lasting from only a few hours to 2 days did not affect the endothelial cell count. Operative glaucoma procedures caused a loss of central endothelial cells of approximately 4.8% in the series. There was a clear correlation between the duration of elevated pressure and the number of central corneal endothelial cells lost.

Non-contact specular micrographs of the corneal endothelium are usually only a few cell diameters in width. The oblong shape leads to uncertainties in the determination of cell density by counting the number of cells on an area of known size. A new method, particularly suited for a long and narrow picture, is described. A line with a length corresponding to 1 mm is drawn on a specular micrograph. The number n of cells sectioned by this line is counted. It is demonstrated that the average cell size A may be determined from n by the formula A = 1 404 669/n2 micron2. The relation between A and n is presented in Table 1, which also gives the corresponding cell density expressed by the number of cells per mm2.

Measurement of corneal endothelial cell density is important both for clinical diagnosis as well as clinical studies. Since endothelial cell loss is considered irreversible in humans, even small changes in endothelial cell density are relevant. Therefore it is important to know whether different instruments for endothelial cell density measurements give the same results and can thus be used interchangeably. In this study we compare corneal endothelial cell density and morphometry measurements from two widely used non-contact specular microscopes, the Topcon SP3000P and Konan Noncon Robo SP8000. Endothelial cell measurements were performed with both the Topcon SP3000P and Konan Noncon Robo SP8000 on 34 eyes of 18 consecutive patients of our cornea clinics with poor image quality being the only exclusion criterion. Images were obtained using the auto-focussing method and manual cell selection. Endothelial cell density (ECD), hexagonal cell ratio (HEX) and coefficient of value (CV) of the endothelial cell layer were calculated by the instruments’ built-in software. ECD values calculated by the Konan were systematically higher than Topcon values: in 94 % of eyes Konan gave a higher value than Topcon, leading to a mean difference in ECD between the instruments of 187 cells/mm2 (P

Pur P ose . To compare the amount of intraoperative energy used during conventional and torsional phacoemulsification surgery and investigate the changes in corneal endothelial cell density. M ethods . In this study, a total of 100 eyes in patients with age-related cataract (mean age 68.9 years) were included. Patients were randomly allocated into conventional (group 1) or torsional (OZil, group 2) phacoemulsification. Mean nuclear grade made according to Lens Opacities Classification System II was not different in the 2 groups. Total ultrasound time (USTT), cumulative dissipated energy (CDE), and the percent of total equivalent power in position 3 (%USTEPiP3) were compared between the 2 groups. results . There were 47 eyes in group 1 and 53 eyes in group 2. Patient age and sex were matched between the 2 groups (p=0.49, p=0.08). Mean USTT was 1.6±1.1 minutes (m) in group 1 and 1.5 ± 0.9 m in group 2 (p=0.55). Average CDE was 29.9±16.9 in group 1 and 25.2±19.1 in group 2 (p=0.20). Mean %USTEPiP3 was 27.0%±8.5% in group 1; however, it was 22.4%±6.6% in group 2 (p=0.003). At the first postoperative day, mean corneal edema was graded as 0.25±0.5 in group 1 and 0.18 ± 0.4 in group 2 (p=0.47). At the first postoperative week, it was found to be 0.02±0.15 in group 1 and 0.03±0.27 in group 2 (p=0.71). ECD loss was 6.7%±3.3% in group 1 and 4.2%±5.7% in group 2 (p=0.56). Con C lusions . No statistically significant difference was found between conventional and torsional phacoemulsification with respect to USTT and CDE. Torsional mode led to a significant reduction in US power in footswitch position 3. Torsional mode also appears to be associated with less loss of ECD (Eur J Ophthalmol 2009: 19: 984-9)

• The endothelium of 40 eyes from 38 diabetics were examined before and after argon photocoagulation. Twenty-two eyes were reexamined six weeks postoperatively. Changes in endothelial cell density were compared with regard to the energy delivered to the eye. There was no statistically significant change in the endothelial cell density in the immediate postoperative period. A statistically significant but small change in endothelial cell density was found in the six-week follow-up group when cell density was compared with energy delivered to the eye by the argon laser photocoagulator. Implications and possible causes for these observations are discussed.