Corneal endothelial cell density and morphology in rabbits eyes using contact specular microscopy / Densidade celular e morfologia das células do endotélio da córnea de coelhos obtidas com microscopia especular

The goal of this study was to describe the normal values of corneal endothelial cell density and hexagonality in healthy rabbits eyes using contact specular microscopy. Both eyes of 18 rabbits, males and females, of different ages were evaluated. The eyes were divided into three groups of 12 each according to the age range of the animals: G1 (6 months old), G2 (12 months old), and G3 (48 months old). Parameters studied included mean endothelial cell density and hexagonality. For Group I, the mean cell density was 2307 cells per mm2. For GII, the mean cell density was 1895 cells per mm2. For G III, the mean cell density was 1818 cells per mm2. Cell density decreased significantly with aging (P 0.001) among the three groups. Pleomorphism in the rabbits of GI was 74.33±10.08. In the rabbits of GII it was 71.83±11.38. In the rabbits of GIII it was 64.02±28.80. Significant differences (P 0.001) were evident between GI and GIII and GII and GIII but not between Groups I and II. The results showed a decrease in number of cells and hexagonality with aging. Corneal endothelium of rabbits suffers changes due to advancing age both in terms of cell density and morphology.

Objetivou-se avaliar a densidade celular e a hexagonalidade do endotélio da cَrnea de coelhos saudلveis usando um microscَpio especular de contato. Os dois olhos de 18 coelhos, machos ou fêmeas, de diferentes idades foram avaliados. Os olhos foram separados em três grupos de 12 olhos cada em funçمo da idade: G1 (6 meses de idade), G2 (12 meses de idade) e G3 (48 meses de idade). Os parâmetros estudados incluيram a densidade celular e a hexagonalidade. Para o Grupo I, a densidade celular média foi de 2307 células por mm2. Para GII, a densidade celular média foi de 1895 células por mm2. Para G III, a densidade celular média foi de 1818 células por mm2. A densidade celular diminuiu significativamente com o envelhecimento (P 0,001) entre os três grupos. O pleomorfismo nos coelhos de GI foi de 74,33±10,08. Nos coelhos do GII foi 71,83±11,38. Nos coelhos de GIII foi de 64,02±28,80. Diferenças significativas (P 0,001) foram evidentes entre GI e GIII e GII e GIII, mas nمo entre os Grupos I e II. Os resultados revelaram diminuiçمo da densidade celular e da hexagonalidade com o avanço da idade. O endotélio da cَrnea de coelhos sofre alteraçُes devido ao avanço da idade tanto na densidade celular e quanto na morfologia.

Corneal endothelial cell density and morphology in rabbits eyes using contact specular microscopy / Densidade celular e morfologia das células do endotélio da córnea de coelhos obtidas com microscopia especular

The goal of this study was to describe the normal values of corneal endothelial cell density and hexagonality in healthy rabbits eyes using contact specular microscopy. Both eyes of 18 rabbits, males and females, of different ages were evaluated. The eyes were divided into three groups of 12 each according to the age range of the animals: G1 (6 months old), G2 (12 months old), and G3 (48 months old). Parameters studied included mean endothelial cell density and hexagonality. For Group I, the mean cell density was 2307 cells per mm2. For GII, the mean cell density was 1895 cells per mm2. For G III, the mean cell density was 1818 cells per mm2. Cell density decreased significantly with aging (P 0.001) among the three groups. Pleomorphism in the rabbits of GI was 74.33±10.08. In the rabbits of GII it was 71.83±11.38. In the rabbits of GIII it was 64.02±28.80. Significant differences (P 0.001) were evident between GI and GIII and GII and GIII but not between Groups I and II. The results showed a decrease in number of cells and hexagonality with aging. Corneal endothelium of rabbits suffers changes due to advancing age both in terms of cell density and morphology.(AU)

Objetivou-se avaliar a densidade celular e a hexagonalidade do endotélio da cَrnea de coelhos saudلveis usando um microscَpio especular de contato. Os dois olhos de 18 coelhos, machos ou fêmeas, de diferentes idades foram avaliados. Os olhos foram separados em três grupos de 12 olhos cada em funçمo da idade: G1 (6 meses de idade), G2 (12 meses de idade) e G3 (48 meses de idade). Os parâmetros estudados incluيram a densidade celular e a hexagonalidade. Para o Grupo I, a densidade celular média foi de 2307 células por mm2. Para GII, a densidade celular média foi de 1895 células por mm2. Para G III, a densidade celular média foi de 1818 células por mm2. A densidade celular diminuiu significativamente com o envelhecimento (P 0,001) entre os três grupos. O pleomorfismo nos coelhos de GI foi de 74,33±10,08. Nos coelhos do GII foi 71,83±11,38. Nos coelhos de GIII foi de 64,02±28,80. Diferenças significativas (P 0,001) foram evidentes entre GI e GIII e GII e GIII, mas nمo entre os Grupos I e II. Os resultados revelaram diminuiçمo da densidade celular e da hexagonalidade com o avanço da idade. O endotélio da cَrnea de coelhos sofre alteraçُes devido ao avanço da idade tanto na densidade celular e quanto na morfologia.(AU)

Utilization of enbucrylate adhesive in the treatment of a corneal ulcer in a horse

Background: Ulcerative keratitis is a common condition in horses, and may leading to vision loss. The high incidence of corneal ulceration in horses is a consequence of several factors, including the large, prominent, laterally positioned eyes, naturally aggressive physical activity, and ubiquitous exposure to bacterial and fungal pathogens. Many surgical techniques have been proposed for the repair of corneal perforation, including conjunctival flaps, keratoplastic procedures, xenografts and biological grafts. In addition, cyanoacrylate adhesives may be used for the treatment of corneal ulcers up to 3 mm in diameter. Cyanoacrylate adhesives have been used to treat small partial corneal lacerations, descemetoceles, deep stromal corneal ulcers, and recurrent corneal erosions, in both human and veterinary ophthalmology. These adhesives allow not only corneal re-epithelialization, with complete sloughing of the glue, but also negative fluorescein retention. In this report, we describe a case of a deep corneal ulcer in a horse that was treated successfully with cyanoacrylate tissue adhesive. Case: A two-month-old female Quarter Horse was referred to the Ophthalmology Section of the Veterinary Clinics Hospital of the Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil, presenting a deep corneal ulcer. The ophthalmic examination revealed ocular discomfort, epiphora, conjunctival hyperemia and a corneal ulcer measuring 3 mm in the left eye of the animal. Surgical repair was performed using an n-butyl-2-cyanoacrylate tissue adhesive. The patient allowed the procedure to be carried out under topical anesthesia alone. The postoperative treatment involved broadspectrum antibiotic (ciprofl oxacin chloridrate 0.35%) and a non-steroidal anti-inflammatory solution (sodium diclofenac 0.1%), administered six times a day for two weeks. In addition, atropine sulphate 1% was applied once a day for five days to induce pupillary dilation. After three weeks of follow-up, the cyanoacrylate adhesive became dislodged from the corneal bed. A fluorescein test was carried out to evaluate the presence of the corneal defect and there was no evidence of the ulcer. The time required for total resolution of the vascularization, which typically leaves a small leukoma, was six weeks. Discussion: The objectives of the treatment included prevention of structural loss, which would compromise globe integrity, resolution of any underlying causes and contributory infectious diseases, improving the patient's comfort by minimizing the development of scar tissue, and maximizing corneal clarity. Although many corneal ulcers are superficial and may heal quickly, a progressive or deep ulcer requires more aggressive therapy. In general, corneal ulcers that involve one-half to two-thirds of the depth of the corneal stroma should be repaired surgically because of the risk of perforation. However, the application of cyanoacrylate adhesives aids corneal healing, by establishing an artificial barrier against polymorphonuclear leucocytes and their enzymes, decreasing stromal melting, and having a bacteriostatic effect on Gram-positive organisms. The choice of surgical method was based on the fact that the adhesive can be applied with topical anesthesia, in its indication for deep ulcers up to 3 mm in diameter, and its advantages in the re-epithelization of the cornea in humans and other animals. In the present case, the use of n-2-butyl-cyanioacrylate offered an effective alternative for the management of a deep corneal defect.