Effects of age and breed on corneal thickness, density, and morphology of corneal endothelial cells in enucleated sheep eyes.

OBJECTIVE The purpose of the study was to determine corneal thickness (CT), endothelial cell density (ECD), morphology, and morphometry in ovine eyes, and to report the effects of age and breed on these parameters. ANIMALS STUDIED AND PROCEDURES Forty-eight healthy ovine eyes were classified into six groups (eight eyes per group) according to animals' age (lambs and adults) and breed (Manchega, Ripollesa, and Rasa Aragonesa). Endothelial cell density (cells/mm(2) ) and CT (μm) were calculated in the central cornea and four peripheral quadrants by means of specular microscopy. Mean cell area (MCA (μm(2) )), pleomorphism (% hexagonal cells), and polymegethism (CV) were evaluated in the central cornea. Statistics consisted of an ANOVA model and a LSD test for the post hoc analysis. RESULTS Results in lambs were as follows: ECD = 3532 ± 259, CT = 699 ± 56, MCA = 283 ± 22, % hexagonal cells = 75.64 ± 3.09, and CV = 18 ± 8.4; and in adults: ECD = 2204 ± 261, CT = 804 ± 87, MCA = 473 ± 53, % hexagonal cells = 69.9 ± 3.42, and CV = 18.1 ± 5.2. There were differences (P < 0.001) in all parameters studied between both groups except for the CV (P = 0.962). Regarding the breed, Rasa Aragonesa presented a higher CT (P = 0.001) and CV (P = 0.04) compared to other breeds. Mean values of all groups together showed that central and dorsal areas of the cornea were the thickest, whereas temporal quadrant was the thinnest (P < 0.001). CONCLUSIONS This study demonstrates that age and breed influence corneal and endothelial parameters in sheep.

[1]  M. Doughty.  A prospective analysis of corneal endothelial polymegethism and cell density in young adult Asians , 2014, Clinical & experimental optometry.

[2]  O. Arslan,et al.  Corneal Endothelial Cell Density and Morphology in Healthy Turkish Eyes , 2014, Journal of ophthalmology.

[3]  R. Ašoklis,et al.  Clinical Interventions in Aging Dovepress Age-related Changes in Corneal Thickness and Endothelial Characteristics Saulius Galgauskas Dovile ˙ Norvydaite ˙ , 2022 .

[4]  A. Bron,et al.  An explanation for the central to peripheral thickness variation in the mouse cornea , 2012, Clinical & experimental ophthalmology.

[5]  Fernando Ussa,et al.  The parameters of the porcine eyeball , 2011, Graefe's Archive for Clinical and Experimental Ophthalmology.

[6]  I. Nolte,et al.  Comparative in Vivo Confocal Microscopical Study of the Cornea Anatomy of Different Laboratory Animals , 2010, Current eye research.

[7]  J. Laus,et al.  Use of specular microscopy to determine corneal endothelial cell morphology and morphometry in enucleated cat eyes. , 2010, Veterinary ophthalmology.

[8]  F. Q. Pereira,et al.  Scanning electron microscopy of the corneal endothelium of ostrich , 2009 .

[9]  J. Laus,et al.  Ultrastructural morphology and morphometry of the normal corneal endothelium of adult crossbred pig , 2009 .

[10]  P. Barros,et al.  Morphological analysis of the corneal endothelium in eyes of dogs using specular microscopy , 2008 .

[11]  J. Prause,et al.  Corneal Thickness in Pigs Measured by Ultrasound Pachymetry In Vivo , 2008 .

[12]  S. Moghimi,et al.  Corneal endothelial cell density and morphology in normal Iranian eyes , 2006, BMC ophthalmology.

[13]  J. Laus,et al.  Corneal endothelial cell morphology of normal dogs in different ages. , 2006, Veterinary ophthalmology.

[14]  V. Ruoppolo,et al.  CORNEAL ENDOTHELIUM OF THE MAGELLANIC PENGUIN (SPHENISCUS MAGELLANICUS) BY SCANNING ELECTRON MICROSCOPY , 2005, Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians.

[15]  T. Almubrad,et al.  Repeatability of central corneal thickness measurements measured with the Topcon SP2000P specular microscope , 2005, Graefe's Archive for Clinical and Experimental Ophthalmology.

[16]  H. Edelhauser,et al.  Increased endothelial cell density in the paracentral and peripheral regions of the human cornea. , 2003, American journal of ophthalmology.

[17]  S. E. Andrew,et al.  Density of corneal endothelial cells, corneal thickness, and corneal diameters in normal eyes of llamas and alpacas. , 2002, American journal of veterinary research.

[18]  F. Abib,et al.  Behavior of corneal endothelial density over a lifetime , 2001, Journal of cataract and refractive surgery.

[19]  J. Hauptman,et al.  Density of corneal endothelial cells and corneal thickness in eyes of euthanatized horses. , 2001, American journal of veterinary research.

[20]  F. A. La Rosa,et al.  Central corneal thickness of Caucasians and African Americans in glaucomatous and nonglaucomatous populations. , 2001, Archives of ophthalmology.

[21]  S. Cheung,et al.  Central and peripheral corneal thickness measured with the TOPCON specular microscope SP-2000P , 2000, Current eye research.

[22]  E. Osuobeni,et al.  Ultrasonographic determination of the dimensions of ocular components in enucleated eyes of the one-humped camel (Camelus dromedarius). , 1999, Research in veterinary science.

[23]  S. Collin,et al.  A comparative study of the corneal endothelium in vertebrates , 1998, Clinical & experimental optometry.

[24]  W M Bourne,et al.  Central corneal endothelial cell changes over a ten-year period. , 1997, Investigative ophthalmology & visual science.

[25]  K. Shimomura,et al.  Specular microscopy of the corneal endothelial cells in common marmosets. , 1996, The Journal of veterinary medical science.

[26]  H. Morita.  Specular microscopy of corneal endothelial cells in rabbits. , 1995, The Journal of veterinary medical science.

[27]  Schoster Jv,et al.  The use of ultrasonic pachymetry and computer enhancement to illustrate the collective corneal thickness profile of 25 cats. , 1995 .

[28]  K. Shimomura,et al.  Specular microscopy of corneal endothelial cells in cynomolgus monkeys. , 1994, The Journal of veterinary medical science.

[29]  R. D. Whitley,et al.  Corneal thickness measured by ultrasonic pachymetry in cats. , 1993, American journal of veterinary research.

[30]  R. D. Whitley,et al.  Canine corneal thickness measured by ultrasonic pachymetry. , 1991, American journal of veterinary research.

[31]  N. Tripoli,et al.  Cat endothelial morphology after corneal transplant. , 1990, Current eye research.

[32]  S. Tuft,et al.  The corneal endothelium , 1990, Eye.

[33]  R. Yee,et al.  Specular microscopy of vertebrate corneal endothelium: a comparative study. , 1987, Experimental eye research.

[34]  N. Rich,et al.  Postnatal development of corneal endothelium. , 1986, Investigative ophthalmology & visual science.

[35]  R O Schultz,et al.  Changes in the normal corneal endothelial cellular pattern as a function of age. , 1985, Current eye research.

[36]  H F Edelhauser,et al.  Comparison of the corneal endothelium in an American and a Japanese population. , 1985, Archives of ophthalmology.

[37]  J. Alvarado,et al.  Prenatal and postnatal cellularity of the human corneal endothelium. A quantitative histologic study. , 1984, Investigative ophthalmology & visual science.

[38]  B. Holden,et al.  Corneal thickness profiles in rabbits using an ultrasonic pachometer. , 1983, Investigative ophthalmology & visual science.

[39]  G. Gum,et al.  Decrease in canine corneal endothelial cell density and increase in corneal thickness as functions of age. , 1982, Investigative ophthalmology & visual science.

[40]  R. Peiffer,et al.  Specular microscopic observations of the corneal endothelium in the normal rabbit , 1981, Laboratory animals.

[41]  R. Peiffer,et al.  Specular microscopic observations of the clinically normal canine corneal endothelium. , 1979, American journal of veterinary research.

[42]  J V Aquavella,et al.  Endothelial cell density in relation to morphology. , 1979, Investigative ophthalmology & visual science.

[43]  C. Hanna,et al.  Endothelial cell population changes of human cornea during life. , 1978, Archives of ophthalmology.

[44]  H. Kaufman,et al.  Comparison of central corneal endothelial cell numbers with peripheral areas. , 1977, American journal of ophthalmology.

[45]  J. Baum,et al.  Central and peripheral corneal thickness. A clinical study. , 1968, Archives of ophthalmology.

[46]  P. Grimes,et al.  Studies on the corneal endothelium of the rabbit. I. Cell division and growth. , 1961, American journal of ophthalmology.