scholarly journals Specular microscopic observations of the corneal endothelium in the normal rabbit

1981 ◽  
Vol 15 (4) ◽  
pp. 393-395 ◽  
Author(s):  
Denise Montanaro Sailstad ◽  
R. L. Peiffer

Endothelial specular microscopy and pachometry were performed on both eyes of 14 young adult New Zealand white rabbits with clinically normal eyes. Endothelial cells of the central corneas formed a mosaic-like pattern of homogenous hexagonal cells with a mean diameter of 20·6 ± 1·0, μm sd. The mean number of cells per mm was 2998 ± 326 sd and the mean corneal thickness was 0·38 ± 0·02 mm sd.

2008 ◽  
Vol 28 (9) ◽  
pp. 427-430 ◽  
Author(s):  
João A.T. Pigatto ◽  
Cristine Cerva ◽  
Cesar D. Freire ◽  
Fernando C. Abib ◽  
Luciano P. Bellini ◽  
...  

Both healthy eyes of 10 six-year-old male and female mongrel dogs were studied. With a contact specular microscope the corneal endothelium was examined. Endothelial cells were analyzed in the central and peripheral cornea. Morphological analysis with regard to polymegathism and pleomorphism was performed. Three images of each region with at least 100 cells were obtained. The analysis showed that polygonal cells formed a mosaic-like pattern uniform in size and shape. The predominant number of cells was hexagonal. The polymegathism index was 0.22. The study demonstrates that the morphology of the normal corneal endothelial cells of dogs is similar to that found in the human cornea.


2020 ◽  
Author(s):  
J Valdez-Garcia ◽  
Gustavo Ortiz-Morales ◽  
Nallely Morales-Mancillas ◽  
Jorge Luis Domene-Hickman ◽  
Julio Hernandez-Camarena ◽  
...  

Abstract Purpose: To assess the corneal endothelial morphometry in healthy elderly Hispanic eyes.Methods: A retrospective, cross-sectional, observational, descriptive, and analytical study was designed to assess by specular microscopy the central region of the corneal endothelium. In a 4-year period, a total of 75 eyes from 42 patients were studied. All eyes included were from patients 65 or older (mean: 73.87±6.86), without ocular disease or surgeries.Results: The mean cell density (MCD) was 2268±597.0 cells/mm2. 44% of patients had polymegethism, with an average coefficient of variation (CV) of 42.04 ± 10.1%. 76% of patients had low pleomorphism, with an average of 42.3 ± 8.9% hexagonal cells. The mean corneal thickness was 537±38.2 μm. There was no statistically significant difference between age groups for MCD, CV, hexagonality and pachymetry (p=>.05). 27% of patients had corneal guttata.Conclusion: This study suggests that the elderly Hispanic population has a high prevalence of polymegethism, pleomorphism and guttata. Surprisingly, the oldest age group (>85) had an above average MCD, low polymegethism and good pleomorphism.


2021 ◽  
pp. 112067212110065
Author(s):  
Murat Serkan Songur ◽  
Yavuz Selim İntepe ◽  
Seray Aslan Bayhan ◽  
Hasan Ali Bayhan ◽  
Ender Şahin ◽  
...  

Purpose: In the present study we evaluate the corneal endothelium using specular microscopy in patients with obstructive sleep apnea syndrome (OSAS). Methods: The study included a total of 100 patients including 35 patients with mild OSAS, 34 patients with moderate OSAS and 31 patients with severe OSAS, and the right eyes of 30 patients as a control group. Patients were examined to exclude the possibility of ocular diseases. Cellular density in the cornea epithelium (cell/mm2), corneal thickness (µ), percentage of hexagonal cells (%) and the coefficient of variation were evaluated using a specular microscope. Results: Corneal thickness was significantly decreased in all OSAS groups when compared to the control group ( p = 0.002), while no significant difference was identified among the OSAS groups. The corneal endothelial cell density, percentage of hexagonal cells and coefficient of variation were significantly different between the OSAS groups and the control group ( p < 0.001). Conclusion: More significant impairments were noted in the corneal endothelium of the patients in the OSAS group than in the control group, and specular microscopy is in valuable in the follow-up and treatment of such patients.


1978 ◽  
Vol 12 (1) ◽  
pp. 37-39 ◽  
Author(s):  
M. Macari ◽  
C. R. Machado

Semen was collected weekly from New Zealand white rabbits from the 1st positive mounting test to 43 weeks of age by means of an artificial vagina. The mean values of the results obtained in the 1st and 20th collection weeks were respectively: volume (ml) 0·61 ± 0·30 and 0·70 ± 0·19; pH 7·22 ± 0·50 and 7·19 ± 0±15; concentration (sperm/mm3 x 103) 750 ± 207 and 381 ± 90; fructose (mg/l00 ml) 117 ± 58 and 203 ± 121; citric acid (mg/l00 ml) 256 ± 90 and 200 ± 97; sodium ions (mEq/l) 133 ± 31 and 163 ± 46; potassium ions (mEq/l) 40 ± 21 and 29 ± 14. On the basis of these results, New Zealand white rabbits reach sexual maturity by 6 months of age.


1996 ◽  
Vol 33 (6) ◽  
pp. 721-724 ◽  
Author(s):  
X. Li ◽  
J. G. Fox ◽  
S. E. Erdman ◽  
N. S. Lipman

A retrospective study revealed intestinal plasmacytosis in 53 of 102 rabbits used in various experimental studies and as controls. The breeds affected included New Zealand white ( n = 46), Dutch-belted ( n = 6), and Watanabe ( n = 1) rabbits. Sex predisposition was not found in any breed. The mean (± SD) ages were 3.1 ± 1.4 years for New Zealand white rabbits, 1.3 ± 1.1 for Dutch-belted rabbits, and 2 years for the Watanabe rabbit. The severity increased with animal age. The incidence was higher ( P < 0.05) in rabbits used in antibody production and cholesterol studies. The lesions were characterized by multifocal to diffuse infiltration of well-differentiated plasma cells in the intestinal mucosa. Electron microscopic examination revealed typical plasma cell morphology of the infiltrating cells. Small intestine and cecum were the major sites affected. In severe cases, colon, rectum, trachea, esophagus, mesenteric lymph node, and spleen were also involved.


2020 ◽  
Vol 36 (4) ◽  
Author(s):  
Abd Elaziz Mohamed Elmadina ◽  
Raghda Faisal Abdelfatah ◽  
Saif Hassan Alrasheed ◽  
Mustafa Abdu ◽  
Manzoor Ahmad Qureshi

Purpose:  To compare the corneal endothelial cells morphology and central corneal thickness (CCT) before and after phacoemulsification in Sudanese population. Place and Duration of Study:  Al-Neelain eye hospital, Khartoum, Sudan, from January 2018 to May 2018. Study Design:  Observational longitudinal study. Methods:  One hundred and forty eyes of 140 patients with immature senile cataract were selected by convenient sampling. The age ranged from 40 to 85 years. The patients underwent complete ocular examination including morphology of corneal endothelial cells and CCT using computerized non-contact specular microscope. Inclusion criteria for the study was eyes with normal corneal endothelial cells and cell density more than 1000 cells/mm2. We excluded patients with ocular or systemic diseases, previous history of intraocular surgery, refractive surgery or trauma as well as contact lenses wear. The patients underwent phacoemulsification by a single surgeon. The examination parameters were repeated one month after surgery. Descriptive and comparative statistical analyses were performed using SPSS for Windows Version 21.0. Results:  There was significant reduction in mean endothelial cells density after phacoemulsification compared to baseline with p < 0.001. There was also significant post-operative reduction in mean endothelial cells number as compared to baseline (P value < 0.001). Mean endothelial cells hexagonality was reduced after surgery with P value of 0.003. No significant difference was found between mean coefficient variation of endothelial cells size before and after phacoemulsification (P = 0.55). Central corneal thickness showed significant increase post-operatively, P = 0.003. Conclusion:  Phacoemulsification causes significant damage to corneal endothelium cells, including decrease in corneal endothelial cell density, hexagonality and cell number. Key Words:  Corneal endothelium, Endothelial cell density, Central corneal thickness, Phacoemulsification.


2019 ◽  
Vol 47 (1) ◽  
Author(s):  
Lídia Luzia Clerot ◽  
Paula Stieven Hünning ◽  
Marcelle Bettio ◽  
Marcela Torikachvili ◽  
Michelle Beck Petersen ◽  
...  

Background: The corneal endothelium is a monolayer of polygonal cells which constitute the last layer of the cornea. The integrity of this layer is critical to cornea transparency. The characterization of normal corneal endothelial morphology is important not only to clinical evaluation but also to selection of areas of the cornea with better quality to be employed as donor tissue. The aim of the present study was to evaluate the morphology of endothelial cells from different regions of the swine cornea after alizarin red staining using optical microscopy.Materials, Methods & Results: Twenty-four healthy eyes from 12 swine Large White breed, with 14-month-old, males or females obtained from a licensed Brazilian commercial slaughterhouse were studied. Immediately after humane slaughter, the eyes were enucleated and submitted to ophthalmic examination. Eyes with signs of diseases of the anterior segment were excluded. The cornea, with 3 mm of the sclera, was removed and placed on a glass microscope slide with the endothelial side up. Four radial incisions were made in the periphery of the cornea to better accommodate the cornea on the microscope slide. Alizarin red was diluted in isotonic solution (0.2 g/100 mL) and the pH was adjusted to 4.2 with hydrochloric acid. Three drops of alizarin red were placed on the corneal endothelium. After 90 s, the dye was removed from the cornea with balanced saline solution. The corneal endothelium was examined and photographed using an optical microscope. All evaluations were performed by the same investigator. Photomicrographs were taken of central, superior, inferior, nasal and temporal corneal areas. Parameter studied included endothelial cell morphology. For the statistical analysis, was employed the ANOVA variance test (repeated measures). Differences were considered statistically significant at P < 0.05. Normal endothelium cells were mainly hexagonal (83.7%), pentagonal (7.45%) and heptagonal (8.8%), with a minimal number of cells of other shapes present. There were no significant statistical differences in the proportion of the morphology and the different regions of the cornea (P = 0.31).Discussion: Different techniques are available for the analysis of corneal endothelium, including mainly scanning electron microscopy, specular microscopy and optical microscopy. The analysis of the morphology of corneal endothelium with an optic microscope after staining with alizarin red has been described as an effective, rapid and cost-efficient method, since this dye blends the borated cells, allowing identification. In the present study, using optical microscopy and coloration with alizarin red it was possible to explore and to obtain images of the swine endothelium of all regions of the cornea.  The analysis of the cellular morphology or the percentage of hexagonal cells are among the main parameters used to evaluate the health of the corneal endothelium. In this study, the endothelium had the predominance of the hexagonal shape in all regions studied. In swine, there are no studies evaluating the shape of the endothelial cells in the five different regions of the cornea. This study has demonstrated that the parameters evaluated in swine did not differ significantly between the various places of the cornea.


2018 ◽  
Vol 5 (3) ◽  
pp. 694 ◽  
Author(s):  
Nagaraj G. ◽  
Anasuya Sangaraj Desai ◽  
Nagesh Jayaram

Background: Diabetes mellitus is associated with structural changes in corneal endothelial cells and their thickness. The present study was done to compare the endothelial cell density (ECD), central corneal thickness (CCT) and morphology in diabetic and non-diabetic patients.Methods: A cross-sectional study was conducted at Minto Ophthalmic hospital, BMC and RI Bangalore for a period of 20 months (October 2013 - May 2015). A total of 200 study subjects, 100 diabetics and 100 non-diabetic age matched controls were selected, and complete timed ophthalmic evaluation was performed. Specular microscopy was performed on all patients for endothelial cell count assessment and corneal thickness was measured by Pachymeter. The data was analyzed and represented using descriptive statistics. ‘t’ test was used for comparing the two groups.Results: The mean endothelial cell density in diabetic group was significantly lower (2438.73±250.23cells/mm2) compared to non-diabetic group (2599.88±168.16cells/mm2) (p<0.0001). The mean Central corneal thickness in diabetic group was significantly higher (518.40±28.13 μm) compared to control group (490.14±24.31 μm) (p<0.001). The Co-efficient of variation percentage of the diabetics was higher than the non-diabetics but this difference was not statistically significant (P>0.05). The hexagonality percentage was significantly lower in diabetic group compared to the controls suggesting less pleomorphism in the diabetic group.Conclusions: The study concludes that the endothelial cell density was lower and central corneal thickness was higher in diabetic patients compared with the non-diabetics. The altered endothelial morphology was significantly seen in the form of pleomorphism (hexagonality) but polymegathism was not significantly altered.


2020 ◽  
Author(s):  
Napaporn Tananuvat ◽  
Natawan Khumchoo

Abstract Background: This study aimed to determine the influence of age on central corneal thickness and corneal endothelial morphology as well as to identify the relationship between them in normal Thai eyes.Methods: Non-contact specular microscopy was performed in volunteers stratified into seven age groups ranging from 11-88 years. The corneal endothelial parameters studied included central corneal thickness (CCT), endothelial cell density (ECD), coefficient of variation in cell size (CV), cell area (CA) and percentage of regular hexagonal cells.Results: In a total of 501 subjects (1002 eyes), the mean age was 43.12 ± 18.80 years and 347(69.3%) were females. The mean CCT, ECD, CV, CA, and hexagonality was 533.80 ± 33.00 μm, 2,732±258 cell/mm2, 37.61 ± 6.76%, 369.04 ± 37.90 mm, and 49.03% ± 7.53%, respectively. There was a statistically significant inverse correlation between age and CCT (r = -0.212, P <0.001), ECD (r = -0.484, P <0.001), and hexagonality (r = -0.193, P <0.001). The estimate rate of endothelial cell loss was 0.2% per year, whereas CV and CA had statistically significant correlation with age (r = 0.200, P <0.001 and r = 0.475, P <0.001). CCT correlated directly with ECD (r = 0.177, P <0.001).Conclusion: Normative data for corneal endothelial morphology in healthy Thai eyes showed that ECD, CCT, and hexagonality were significantly decreased, while CV and CA were increased with aging. The central corneal thickness was correlated with the endothelial cell density.


Sign in / Sign up

Export Citation Format

Share Document