Ex vivo evaluation of anterior lens capsule staining in horses with three concentrations of gentian violet for surgical training / Avaliação ex vivo da coloração da cápsula anterior da lente de cavalos com três concentrações de violeta genciana para treinamento cirúrgico

Abstract The aim of this study was to evaluate and compare the effectiveness of three concentrations of gentian violet (0.5%, 0.1% and 0.05%) for staining the anterior capsule of the lens in horses. Thirty-six post-mortem equine eyes were collected. The eyes were subdivided into three groups composed of 12 eyes each, according to the concentration of gentian violet used. The effectiveness of staining the anterior capsule of the lens with different concentrations of gentian violet was assessed using an empirical system of evaluation on adequate or inadequate staining of capsular flaps. Based on the evaluation of the examiner, the 0.1% and 0.05% concentrations of gentian violet allowed adequate visualisation of the anterior capsule for continuous curvilinear capsulotomy training, whereas the 0.5% concentration produced strong and inadequate capsular staining. The model developed using gentian violet at concentrations of 0.1% and 0.05% allowed a clear visualisation of the capsular flap, which makes it viable as a model for training the continuous curvilinear capsulotomy step in cataract surgery in horses.

Resumo O objetivo deste estudo foi avaliar e comparar a eficácia de três concentrações de violeta genciana (0,5%, 0,1% e 0,05%) na coloração da cápsula anterior da lente em equinos. Trinta e seis olhos de equinos post-morten foram utilizados. De acordo com a concentração de violeta genciana utilizada, os olhos foram subdivididos em três grupos compostos por 12 olhos cada. A avaliação da eficácia em coloração da cápsula anterior da lente com diferentes concentrações de violeta de genciana foi realizada por meio de um sistema empírico de avaliação da coloração adequada ou inadequada de retalhos capsulares. Com base na avaliação dos examinadores, as concentrações de 0,1% e 0,05% de violeta de genciana permitiram a visualização adequada da cápsula anterior para o treinamento da capsulotomia curvilínea contínua enquanto a concentração de 0,5% produziu uma coloração capsular forte e inadequada. O modelo desenvolvido com violeta genciana, nas concentrações de 0,1% e 0,05%, permitiu a visualização nítida do retalho capsular, o que o torna viável como modelo para treinamento da etapa de capsulotomia curvilínea contínua em cirurgia de catarata em equinos.

Specular microscopy of the corneal endothelial cells of bovines: an ex vivo study.

Background: The endothelium is the most posterior layer of the cornea and is essential for maintaining corneal transparency. Due to variations in corneal endothelial parameters among different species, knowledge of the normal parameters for each species is crucial. Aim: To evaluate the corneal endothelium of bovines using contact specular microscopy. Methods: Twenty eyeballs from 10 male Brangus (Bos taurus) aged 24 months were evaluated. Contact specular microscopy was performed on the central corneal area. The analyzed parameters were endothelial cell density (ECD) and endothelial cell morphology. Results: The ECD in the central area was 1,277 cells/mm2. Regarding the morphology, mainly cells with six (74.3%), five (14.7%) and seven sides (10%) were found. There were no significant differences in ECD and morphology between left and right eyes. Conclusion: Contact specular microscopy facilitated the analysis and measurement of corneal endothelial parameters in bovines. The data obtained will serve as a reference for the analysis of bovine corneal endothelium.

Specular microscopy of the different regions of the cornea in enucleated swine eyes: ex vivo evaluation / Microscopia especular das diferentes regiões da córnea de suínos: estudo ex vivo

The objective of this study was to determine the endothelial cell density (ECD) and hexagonality of the cornea in the different regions of healthy swine corneal endothelium using specular microscopy. Twenty-four eyeballs from 12 male, 6-month-old Large White pigs (Sus scrofa domesticus) were studied. Contact specular microscopy was performed in the central, superior, inferior, lateral and medial regions. The corneal parameters analysed in this study were ECD and hexagonality. The ECD in the central region was 1865 cells/mm2; in the upper region, it was 1877 cells/mm2, in the lower region, it was 1854 cells/mm2, in the lateral region, it was 1847 cells/mm2, in the medial region, it was 1831 cells/mm2. Hexagonality in the central region, was 53%; in the upper region, it was 54%, in the lower region, it was 54%, in the lateral region, it was 54%, in the medial region, it was 54%. There was no significant difference regarding to the evaluated parameters in all corneal regions evaluated. No statistically significantly differences were observed in ECD and hexagonality between the left and the right eyes. This study demonstrates that ECD and hexagonality of the central cornea area represent the entire endothelial mosaic.

O objetivo do presente estudo foi avaliar a densidade endotelial e a hexagonalidade das células endoteliais nas diferentes regiões da córnea de suínos utilizando a microscopia especular de contato. Foram estudados 24 bulbos oculares de 12 suínos (Sus scrofa domesticus), machos, com seis meses de idade e da raça Large White. A microscopia especular de contato foi realizada nas regiões central, superior, inferior, lateral e medial da córnea. A densidade endotelial média na região central foi de 1865 células/mm2, na região superior foi de 1877 células/mm2, na região inferior foi de 1854 células/mm2, na região lateral foi de 1847 células/mm2 e na região medial foi de 1831 células/mm2. Na região central, a hexagonalidade foi de 53%, na região superior foi de 54%, na região inferior foi de 54%, na região lateral foi de 54%, na região medial foi de 54%. Não foram observadas diferenças significativas na densidade celular e na hexagonalidade nas diferentes regiões da córnea analisadas. Este estudo demonstrou que a densidade endotelial e a hexagonalidade da área central da córnea representam todo o mosaico endotelial.

Evaluation of the corneal epithelium of rabbits treated with preservative-free eye drops containing ketorolac tromethamine or diclofenac sodium / Avaliação dos colírios cetorolaco de trometamina e diclofenaco sódico sem conservantes no epitélio da córnea de coelhos

This study aimed to evaluate the corneal epitheliotoxic effects of preservative-free ketorolac tromethamine 0.5% and diclofenac sodium 0.1% eye drops in rabbits. Seventeen New Zealand rabbits were randomly divided into three groups: the 0.5% ketorolac tromethamine group, the 0.1% diclofenac sodium group, and the control group (0.9% NaCl). For each rabbit, both eyes were treated three times daily according to their treatment group. The corneal epithelia were analyzed using scanning electron microscopy to observe the number of light, grey, and dark cells; the number of epithelial holes; and the loss of hexagonal shape. Both of the formulations administered caused changes in the healthy corneal epithelia of rabbits. Except for number of epithelial holes (p < 0.05), all the parameters showed a statistically significant difference between the groups. The number of dark cells was highest in the ketorolac tromethamine group (p<0.05). The number of grey cells was higher in the diclofenac sodium group than in the control group (p =0.003). A higher number of dark cells was associated with a smaller number of light cells (r =-0.577, p < 0.001). Loss of shape showed a direct correlation with the number of dark cells (r=0.524, p=0.002). Based on the results presented, it was possible to conclude that ketorolac tromethamine 0.5% was more toxic to rabbit corneal epithelium than diclofenac sodium 0.1%.

Objetivou-se avaliar os efeitos do cetorolaco de trometamina a 0,5% e do diclofenaco de sódico a 0,1% sem conservantes na córnea de coelhos. Dezessete coelhos da raça Nova Zelândia foram aleatoriamente divididos em três grupos: o grupo de 0,5% de cetorolaco de trometamina, o grupo de 0,1% de diclofenaco sódico e o grupo controle (0,9% de NaCl). Para cada coelho, os dois olhos foram tratados três vezes ao dia durante 90 dias de acordo com o grupo de tratamento. Os epitélios da córnea foram analisados usando microscopia eletrônica de varredura para observar o número de células claras, cinzas e escuras, o número de criptas e a perda do formato celular hexagonal. Ambas as formulações administradas causaram alterações no epitélio da córnea de coelhos. Com exceção da contagem de criptas (p <0,05), todos os parâmetros apresentaram diferença estatisticamente significante entre os grupos. O número de células escuras foi maior no grupo cetorolaco de trometamina (p <0,05). O número de células cinzentas foi maior no grupo diclofenaco de sódio do que no grupo controle (p=0,003). O maior número de células escuras observado foi associado ao menor número de células claras (r=-0,577, p<0,001). A perda do formato celular mostrou uma correlação direta com o número de células escuras (r=0,524, p=0,002). O cetorolaco de trometamina 0,5% foi mais tóxico para o epitélio da córnea de coelhos do que o diclofenaco de sódio a 0,1%.

Sheep corneal endothelium morphology - evaluation with trypan blue and alizarin red

Background: The endothelium is a layer fundamental to maintaining corneal transparency. In ophthalmology, sheep eyes have been used as a model in research related to corneal transplantation. Different techniques have been used to evaluate the corneal endothelium. Concerning vital dyes, corneal endothelial cell analyses have not yet been studied in ovines. The purpose of the present study was to evaluate the morphology of endothelial cells from different regions of the cornea of sheep after staining with alizarin red and trypan blue using an optical microscope. Materials, Methods & Results: Twenty healthy eyes of 10 male sheep obtained from a licensed commercial slaughterhouse were studied. The study was approved by the Research Committee of the Faculty of Veterinary at UFRGS and followed the ethical standards of the Association for Research in Vision and Ophthalmology (ARVO). Immediately after the slaughter, the eyes were enucleated and underwent eye examination. The corneal endothelium was stained with trypan blue and alizarin red and examined and photographed using an optical microscope. The central, superior, inferior, nasal and temporal areas of the cornea were evaluated for cell morphology. Data were compared by t-tests. Differences were considered statistically significant at P < 0.05. Immediately after staining the corneal endothelium, it was possible to examine with an optical microscope, obtain images and analyse the shape of endothelial cells from all regions of the sheep cornea. Polygonal, uniform and continuous cells were observed in all samples studied. Considering all the corneas analysed, cells with 6 sides (75.11%), 5 sides (12.76%) and 4 sides (12.12%) were found. In the central region of the cornea 75.91% of cells with 6 sides, 12.6% of cells with 5 sides and 11.48% with 7 sides were found. In the superior region of the cornea 76.07% of cells with 6 sides, 13.25% with 5 sides and 10.68% with 7 sides were found. In the lower region were found 74.72% of cells with 6 sides, 13% with 5 sides and 12.27% with 7 sides. In the temporal region, 74.14% were 6-sided cells, 11.42% had 5 sides, and 14.43% had 7 sides. Furthermore, in the nasal region, 74.72% of the cells had 6 sides, 13.54% had 5 sides, and 11.73% had 7 sides. No significant differences were found between cell morphology in all corneal regions evaluated. In addition, no significant difference was found when comparing the right eye with the left eye. Discussion: Different methods are used for the analysis of corneal endothelium. For ex vivo research optical microscopy after endothelial staining is an alternative low-cost technique that allows the analysis of all regions of the cornea. Quantitative analyses must characterise the endothelial parameters of the different species. 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 with the borated cells, allowing identification. In the present study, using optical microscopy and coloration with alizarin red it was possible to explore and obtain images of the ovine endothelium of all regions of the cornea. In the current study, the endothelium had a predominance of cells will 6 sides in all regions studied. This study allowed us to obtain images of the endothelium as well as quantitative data on the morphology of the different regions of the sheep cornea. This study demonstrated that morphology did not differ between the central and peripheral regions. The findings of this study represent a further source of reproducible data that should be considered when using sheep cornea as ex vivo model for experimental research.

Effects of daily curve and age on intraocular pressure in Criollo horses / Efeitos da curva diária e da idade na pressão intraocular em cavalos Crioulos

The objective of this study was to evaluate the intraocular pressure (IOP) of healthy Criollo horses using a rebound tonometer throughout the day. In addition, assessments were made in horses of different ages. Twenty-seven horses, male and female, were divided into three groups by age: Group I (3-5 years old), Group II (6-8 years old), and Group III: (9-16 years old). Ophthalmic examinations were performed using the Schirmer tear test, slit-lamp biomicroscopy, fluorescein test and indirect ophthalmoscopy. Seven measurements of IOP were assessed on the same day (at 6:00 am, 9:00 am, 12:00 am, 3:00 pm, 6:00 pm, 9:00 pm and 00:00 pm). A t-test was used when there were two groups of comparisons and ANOVA was used to detect differences in IOP between measurement times and between age categories. The average IOP was 28.4 ± 3.7 mmHg for all eyes. The mean IOP for Groups I, II and III were 29.2 ± 3.5, 28.4 ± 4.3 and 27.7 ± 3.2 mmHg, respectively. There was no statistically difference between right and left eyes. There was a significant difference between Group I and Group III (P = 0.008). There were no statistically significant differences between measurements recorded at different times of the day (P = 0.560). The IOP was not influenced by the circadian rhythm, but older horses showed reduced IOP.

O objetivo deste estudo foi avaliar a pressão intraocular (PIO) com um tonômetro rebote em cavalos da raça Crioula ao longo do dia. Além disso, foram realizadas avaliações em cavalos de diferentes idades. Vinte e sete cavalos, machos ou fêmeas foram divididos em três grupos de acordo com a idade: Grupo I (3 a 5 anos), Grupo II (6 a 8 anos) e Grupo III (9 a 16 anos). O exame oftálmico incluiu teste da lágrima de Schirmer, biomicroscopia com lâmpada de fenda, prova da fluoresceína e oftalmoscopia indireta. Sete medidas de PIO foram realizadas no mesmo dia (às 6h, 9h, 12h, 15h, 18h, 21h e 24h). O teste t foi usado quando havia dois grupos de comparações e a análise de variância (ANOVA) foi usada para detectar diferenças na PIO entre os momentos de medição e entre as categorias de idade. A PIO média foi de 28,4 ± 3,7 mmHg para todos os olhos. A PIO média dos grupos I, II e III foi de 29,2 ± 3,5, 28,4 ± 4,3 e 27,7 ± 3,2 mmHg, respectivamente. Não houve diferença estatística entre os olhos direito e esquerdo. Houve diferença entre o grupo I e o grupo III (P = 0,008). Não houve diferença entre as medidas registradas em diferentes momentos do dia (P = 0,560). A PIO aferida com tonômetro de rebote em cavalos da raça Crioula saudáveis não sofreu influência da hora do dia em que foi realizada, mas foi menor em equinos mais velhos.

Acute effects of ropivacaine hydrochloride on corneal endothelial cell ultrastructure of horses: ex vivo study / Efeitos agudos do cloridrato de ropivacaína na ultraestrutura das células endoteliais da córnea de equinos: estudo ex vivo

The objective of this study was to evaluate the acute effects of ropivacaine hydrochloride on the corneal endothelium of horses. Forty-eight eyes were obtained from a commercial slaughterhouse and were randomly divided into three groups. In group A, the corneal endothelium was exposed to 0.75% ropivacaine hydrochloride for 60 seconds. In group B, the corneal endothelium was exposed to 0.75% ropivacaine hydrochloride for 15 minutes. In group C, the corneal endothelium was exposed to a balanced saline solution for 60 seconds. Afterwards, all samples were prepared for evaluation with scanning electron microscopy. Random electromicrographs were obtained from each sample. The images were analysed and, with the aid of software, areas with no endothelial cells were measured. The average endothelial loss, expressed as a percentage in relation to the total area, of the samples in group A was 5.28%. The average endothelial loss of samples from group B, expressed as a percentage in relation to the total area, was 20.39%. The damage to the corneal endothelium was significantly greater in group B compared to groups A and C. It was possible to conclude that 0.75% ropivacaine hydrochloride induced acute damage to corneal endothelium cells.(AU)

Objetivou-se avaliar os efeitos agudos do cloridrato de ropivacaína no endotélio da córnea de equinos. Quarenta e oito olhos de equinos foram divididos aleatoriamente em três grupos. No grupo A o endotélio da córnea foi exposto a cloridrato de ropivacaína a 0,75% por 60 segundos. No grupo B o endotélio da córnea foi exposto a cloridrato de ropivacaína a 0,75% por 15 minutos. No grupo C o endotélio da córnea foi exposto à solução salina balanceada por 60 segundos. As amostras foram preparadas para avaliação com microscopia eletrônica de varredura. Eletromicrografias eletrônicas de varredura foram obtidas aleatoriamente de cada amostra. As imagens foram analisadas e, com o auxílio de um programa para morfometria foram medidas as áreas sem células endoteliais. A perda endotelial média foi expressa em porcentagem em relação à área total das amostras do grupo A foi de 5,28%. A perda endotelial média de amostras do grupo B foi expressa em porcentagem em relação à área total, foi de 20,39%. O dano ao endotélio da córnea foi significativamente maior no grupo B, comparado aos grupos A e C. O cloridrato de ropivacaína a 0,75% induziu dano agudo nas células do endotélio da córnea de equinos.(AU)

Acute effects of ropivacaine hydrochloride on corneal endothelial cell ultrastructure of horses: ex vivo study / Efeitos agudos do cloridrato de ropivacaína na ultraestrutura das células endoteliais da córnea de equinos: estudo ex vivo

The objective of this study was to evaluate the acute effects of ropivacaine hydrochloride on the corneal endothelium of horses. Forty-eight eyes were obtained from a commercial slaughterhouse and were randomly divided into three groups. In group A, the corneal endothelium was exposed to 0.75% ropivacaine hydrochloride for 60 seconds. In group B, the corneal endothelium was exposed to 0.75% ropivacaine hydrochloride for 15 minutes. In group C, the corneal endothelium was exposed to a balanced saline solution for 60 seconds. Afterwards, all samples were prepared for evaluation with scanning electron microscopy. Random electromicrographs were obtained from each sample. The images were analysed and, with the aid of software, areas with no endothelial cells were measured. The average endothelial loss, expressed as a percentage in relation to the total area, of the samples in group A was 5.28%. The average endothelial loss of samples from group B, expressed as a percentage in relation to the total area, was 20.39%. The damage to the corneal endothelium was significantly greater in group B compared to groups A and C. It was possible to conclude that 0.75% ropivacaine hydrochloride induced acute damage to corneal endothelium cells.

Objetivou-se avaliar os efeitos agudos do cloridrato de ropivacaína no endotélio da córnea de equinos. Quarenta e oito olhos de equinos foram divididos aleatoriamente em três grupos. No grupo A o endotélio da córnea foi exposto a cloridrato de ropivacaína a 0,75% por 60 segundos. No grupo B o endotélio da córnea foi exposto a cloridrato de ropivacaína a 0,75% por 15 minutos. No grupo C o endotélio da córnea foi exposto à solução salina balanceada por 60 segundos. As amostras foram preparadas para avaliação com microscopia eletrônica de varredura. Eletromicrografias eletrônicas de varredura foram obtidas aleatoriamente de cada amostra. As imagens foram analisadas e, com o auxílio de um programa para morfometria foram medidas as áreas sem células endoteliais. A perda endotelial média foi expressa em porcentagem em relação à área total das amostras do grupo A foi de 5,28%. A perda endotelial média de amostras do grupo B foi expressa em porcentagem em relação à área total, foi de 20,39%. O dano ao endotélio da córnea foi significativamente maior no grupo B, comparado aos grupos A e C. O cloridrato de ropivacaína a 0,75% induziu dano agudo nas células do endotélio da córnea de equinos.

Modified eye evisceration in a tropical screech owl (Megascops choliba)

Background: An adult owl was presented with an injury to the right eye that rendered it blind in that eye. The left eye was normal. Removal of the right eye was recommended and a modified eye evisceration was performed. No complications were observed during or after surgery. The objective of this paper is to describe the modified eye evisceration technique that was successfully used in a tropical screech owl (Megascops choliba). Case: An adult owl was presented with an injury to the right eye that rendered it blind in that eye. Two previous surgical treatments have been carried out but have not been successful. Using a portable slit-lamp (Kowa SL-15®), both eyes were examined. The left eye was normal. Upon ophthalmic examination of the right eye, the owl demonstrated blepharospasm and large central corneal ulcer. Removal of the right eye was recommended. The bird received midazolam hydrochloride [Dormire® - 1 mg/kg, IM] and ketamine hydrochloride [Ketamina® - 5 mg/kg IM] as pre-anesthetic medications. Subsequently, the bird was anesthetized with isoflurane (Isoforine®) by facemask for induction, and then maintained with isoflurane vaporized in 100% oxygen through an endotracheal tube. With the aid of a surgical microscope and microsurgery materials, a modified eye evisceration was performed. Post-operatively, the owl received meloxicam [Maxicam® - 0.5 mg/kg, IM] and tramadol hydrochloride [Cronidor® - 15 mg/kg, orally for 4 days]. The day after surgery, the owl was comfortable and its usual appetite was regained. The patient remained hospitalized for 3 weeks and was evaluated daily. The skin sutures were removed 10 days after the surgical procedure and the surgical wound had healed normally. The patient was reintroduced into the wild after 2 months. During the 6 months post-release, the bird was evaluated once a month, and no complications were observed. Discussion: Severe eye trauma and complicated corneal ulcers are common causes of eyeball removal in birds. In birds, there is a high risk of complications during enucleation. The fragility of the orbital bones makes them susceptible to trauma during the surgery. Evisceration involves the removal of the inner contents of the eye while leaving the cornea and the sclera intact. In the current case, evisceration was chosen because the eye was blind, and maintaining a blind eye would be a source of pain and infection. In the modified evisceration technique, the risk of complications is minimal compared to enucleation, mainly because surgical manipulation is minimal. In our case, the total surgery time was 20 min. Another complication reported after enucleation in birds is the possibility of disfiguring the bird because the removal of the globe disturbs the natural head balance. To avoid these complications, the use of an intraocular prosthesis after evisceration in birds has been performed. However, owls have a tubular-shaped globe with scleral ossicles. These factors could hinder or even prevent the accommodation of a cylindrical silicone prosthesis. In the present case, an intraocular prosthesis implant was never considered due to the unavailability of the prosthesis and to avoid the risk of postoperative complications that have been reported from the literature in dogs. In this case, the owl recovered well from anesthesia without complications, and no postoperative hemorrhage was observed. No signs of pain were observed during the postoperative period and the owl had already shown an appetite and fed on the first postoperative day. The previously published reports using the modified evisceration technique also demonstrated an absence of pain signs during the postoperative period.(AU)

Effects of daily curve and age on intraocular pressure in Criollo horses / Efeitos da curva diária e da idade na pressão intraocular em cavalos Crioulos

The objective of this study was to evaluate the intraocular pressure (IOP) of healthy Criollo horses using a rebound tonometer throughout the day. In addition, assessments were made in horses of different ages. Twenty-seven horses, male and female, were divided into three groups by age: Group I (3-5 years old), Group II (6-8 years old), and Group III: (9-16 years old). Ophthalmic examinations were performed using the Schirmer tear test, slit-lamp biomicroscopy, fluorescein test and indirect ophthalmoscopy. Seven measurements of IOP were assessed on the same day (at 6:00 am, 9:00 am, 12:00 am, 3:00 pm, 6:00 pm, 9:00 pm and 00:00 pm). A t-test was used when there were two groups of comparisons and ANOVA was used to detect differences in IOP between measurement times and between age categories. The average IOP was 28.4 ± 3.7 mmHg for all eyes. The mean IOP for Groups I, II and III were 29.2 ± 3.5, 28.4 ± 4.3 and 27.7 ± 3.2 mmHg, respectively. There was no statistically difference between right and left eyes. There was a significant difference between Group I and Group III (P = 0.008). There were no statistically significant differences between measurements recorded at different times of the day (P = 0.560). The IOP was not influenced by the circadian rhythm, but older horses showed reduced IOP.(AU)

O objetivo deste estudo foi avaliar a pressão intraocular (PIO) com um tonômetro rebote em cavalos da raça Crioula ao longo do dia. Além disso, foram realizadas avaliações em cavalos de diferentes idades. Vinte e sete cavalos, machos ou fêmeas foram divididos em três grupos de acordo com a idade: Grupo I (3 a 5 anos), Grupo II (6 a 8 anos) e Grupo III (9 a 16 anos). O exame oftálmico incluiu teste da lágrima de Schirmer, biomicroscopia com lâmpada de fenda, prova da fluoresceína e oftalmoscopia indireta. Sete medidas de PIO foram realizadas no mesmo dia (às 6h, 9h, 12h, 15h, 18h, 21h e 24h). O teste t foi usado quando havia dois grupos de comparações e a análise de variância (ANOVA) foi usada para detectar diferenças na PIO entre os momentos de medição e entre as categorias de idade. A PIO média foi de 28,4 ± 3,7 mmHg para todos os olhos. A PIO média dos grupos I, II e III foi de 29,2 ± 3,5, 28,4 ± 4,3 e 27,7 ± 3,2 mmHg, respectivamente. Não houve diferença estatística entre os olhos direito e esquerdo. Houve diferença entre o grupo I e o grupo III (P = 0,008). Não houve diferença entre as medidas registradas em diferentes momentos do dia (P = 0,560). A PIO aferida com tonômetro de rebote em cavalos da raça Crioula saudáveis não sofreu influência da hora do dia em que foi realizada, mas foi menor em equinos mais velhos.(AU)

Acute effects of ropivacaine hydrochloride on corneal endothelial cell ultrastructure of horses: ex vivo study / Efeitos agudos do cloridrato de ropivacaína na ultraestrutura das células endoteliais da córnea de equinos: estudo ex vivo

ABSTRACT: The objective of this study was to evaluate the acute effects of ropivacaine hydrochloride on the corneal endothelium of horses. Forty-eight eyes were obtained from a commercial slaughterhouse and were randomly divided into three groups. In group A, the corneal endothelium was exposed to 0.75% ropivacaine hydrochloride for 60 seconds. In group B, the corneal endothelium was exposed to 0.75% ropivacaine hydrochloride for 15 minutes. In group C, the corneal endothelium was exposed to a balanced saline solution for 60 seconds. Afterwards, all samples were prepared for evaluation with scanning electron microscopy. Random electromicrographs were obtained from each sample. The images were analysed and, with the aid of software, areas with no endothelial cells were measured. The average endothelial loss, expressed as a percentage in relation to the total area, of the samples in group A was 5.28%. The average endothelial loss of samples from group B, expressed as a percentage in relation to the total area, was 20.39%. The damage to the corneal endothelium was significantly greater in group B compared to groups A and C. It was possible to conclude that 0.75% ropivacaine hydrochloride induced acute damage to corneal endothelium cells.

RESUMO: Objetivou-se avaliar os efeitos agudos do cloridrato de ropivacaína no endotélio da córnea de equinos. Quarenta e oito olhos de equinos foram divididos aleatoriamente em três grupos. No grupo A o endotélio da córnea foi exposto a cloridrato de ropivacaína a 0,75% por 60 segundos. No grupo B o endotélio da córnea foi exposto a cloridrato de ropivacaína a 0,75% por 15 minutos. No grupo C o endotélio da córnea foi exposto à solução salina balanceada por 60 segundos. As amostras foram preparadas para avaliação com microscopia eletrônica de varredura. Eletromicrografias eletrônicas de varredura foram obtidas aleatoriamente de cada amostra. As imagens foram analisadas e, com o auxílio de um programa para morfometria foram medidas as áreas sem células endoteliais. A perda endotelial média foi expressa em porcentagem em relação à área total das amostras do grupo A foi de 5,28%. A perda endotelial média de amostras do grupo B foi expressa em porcentagem em relação à área total, foi de 20,39%. O dano ao endotélio da córnea foi significativamente maior no grupo B, comparado aos grupos A e C. O cloridrato de ropivacaína a 0,75% induziu dano agudo nas células do endotélio da córnea de equinos.

Treatment of limbal melanocytoma with full excision and a fresh homologous corneoscleral graft in a dog

Background: Limbal melanoma has been diagnosed in dogs and due to progression may cause vision loss and eyeballremoval. Definitive diagnosis is made through histopathological examination. Therapeutic options include full thicknessresection and repair by homologous corneal tissue, synthetic graft material, and enucleation. In this report, we describe acase of limbal melanocitoma in a dog that has been treated successfully with fresh homologous corneoscleral graft.Case: A 5-year-old female Labrador was referred to the Ophthalmology Veterinary Section of the Federal University ofRio Grande do Sul (UFRGS), Porto Alegre, Brazil, with a history of a pigmented mass located on the left eye. Ophthalmicexamination revealed a pigmented mass located at the left temporal limbus with corneal involvement. Surgical excisionfollowed by reconstruction using fresh homologous corneoscleral was recommended. The patient was premedicated withacepromazine (0.05 mg/kg, IM) and meperidine (20 mg/kg, IM). Anaesthesia was induced with propofol (10 mg/kg, IV)and maintained with isoflurane. Atracurium (0.2 mg/kg, IV) was administered to maintain a central eye position. The massand a free margin were removed by full-thickness corneoscleral resection. A corneoscleral graft was harvested from a dogthat had been euthanised for reasons unrelated to this study and sutured with 9-0 polyglactin 910 using a simple interruptedpattern. The mass was immediately fixed in 10% neutral buffered formalin and submitted for histological sectioning androutine staining. Based on the histopathological analysis it was confirmed limbal melanocytoma. Postoperative treatmentconsisted...(AU)

Treatment of limbal melanocytoma with full excision and a fresh homologous corneoscleral graft in a dog

Background: Limbal melanoma has been diagnosed in dogs and due to progression may cause vision loss and eyeballremoval. Definitive diagnosis is made through histopathological examination. Therapeutic options include full thicknessresection and repair by homologous corneal tissue, synthetic graft material, and enucleation. In this report, we describe acase of limbal melanocitoma in a dog that has been treated successfully with fresh homologous corneoscleral graft.Case: A 5-year-old female Labrador was referred to the Ophthalmology Veterinary Section of the Federal University ofRio Grande do Sul (UFRGS), Porto Alegre, Brazil, with a history of a pigmented mass located on the left eye. Ophthalmicexamination revealed a pigmented mass located at the left temporal limbus with corneal involvement. Surgical excisionfollowed by reconstruction using fresh homologous corneoscleral was recommended. The patient was premedicated withacepromazine (0.05 mg/kg, IM) and meperidine (20 mg/kg, IM). Anaesthesia was induced with propofol (10 mg/kg, IV)and maintained with isoflurane. Atracurium (0.2 mg/kg, IV) was administered to maintain a central eye position. The massand a free margin were removed by full-thickness corneoscleral resection. A corneoscleral graft was harvested from a dogthat had been euthanised for reasons unrelated to this study and sutured with 9-0 polyglactin 910 using a simple interruptedpattern. The mass was immediately fixed in 10% neutral buffered formalin and submitted for histological sectioning androutine staining. Based on the histopathological analysis it was confirmed limbal melanocytoma. Postoperative treatmentconsisted...

Evaluation of equine (Equus cabbalus) corneal endothelium stored in EUSOL-C® preservation medium / Avaliação do endotélio da córnea de equinos (Equus cabbalus) acondicionado em meio de preservação de córnea Eusol-C®

The objective of this study was evaluate the maintenance of the corneal endothelium of horses in cold EUSOL-C® preservation medium over different periods (seven and 14 days) using scanning electron microscopy. A total of 20 pairs of eyes from horses were analysed. The corneas were divided into four groups of 10 corneas each (G1, G2, G3 and G4): G1 - the samples were kept in the preservation medium for seven days; G3 - the samples were kept in the preservation medium for for 14 days; G2 and G4 were formed by the control corneal buttons of G1 and G3, respectively. The average cell loss observed in G1 was 7.62%, in G2 it was 7.04%, in G3 9.12% and in G4 7.16%. No statistically significant differences were observed between the four groups. It was concluded that the Eusol-C® hypothermic preservation medium provided satisfactory preservation of the corneal endothelium in equine species for up to 14 days.

Objetivou-se avaliar a manutenção do endotélio da córnea de equinos em meio de preservação a frio EUSOL-C® em diferentes períodos de acondicionamento (sete e 14 dias) utilizando microscopia eletrônica de varredura. Foram avaliados 40 bulbos oculares de 20 equinos. Os bulbos oculares foram divididos em quatro grupos (G1, G2, G3 e G4), nos quais: G1 foi composto por 10 botões corneais acondicionados em meio de preservação para córnea Eusol-C® durante sete dias; o G3 foi formado por 10 botões corneais acondicionados em meio de preservação para córnea Eusol-C® durante 14 dias. O G2 e G4 foram formados pelas córneas controle armazenadas imediatamente em glutaraldeído. A média da perda celular observada no G1 foi de 7,62%, no G2 foi de 7,04 %, no G3 foi de 9,12% e o no G4 foi de 7,16%. Não foram observadas diferenças estatisticamente significativas entre os quatro grupos. Foi possível concluir que o meio de preservação hipotérmico Eusol-C® proporcionou de forma satisfatória a preservação do endotélio da córnea na espécie equina durante o período de até 14 dias.

Evaluation of equine (Equus cabbalus) corneal endothelium stored in EUSOL-C® preservation medium / Avaliação do endotélio da córnea de equinos (Equus cabbalus) acondicionado em meio de preservação de córnea Eusol-C®

The objective of this study was evaluate the maintenance of the corneal endothelium of horses in cold EUSOL-C® preservation medium over different periods (seven and 14 days) using scanning electron microscopy. A total of 20 pairs of eyes from horses were analysed. The corneas were divided into four groups of 10 corneas each (G1, G2, G3 and G4): G1 - the samples were kept in the preservation medium for seven days; G3 - the samples were kept in the preservation medium for for 14 days; G2 and G4 were formed by the control corneal buttons of G1 and G3, respectively. The average cell loss observed in G1 was 7.62%, in G2 it was 7.04%, in G3 9.12% and in G4 7.16%. No statistically significant differences were observed between the four groups. It was concluded that the Eusol-C® hypothermic preservation medium provided satisfactory preservation of the corneal endothelium in equine species for up to 14 days.(AU)

Objetivou-se avaliar a manutenção do endotélio da córnea de equinos em meio de preservação a frio EUSOL-C® em diferentes períodos de acondicionamento (sete e 14 dias) utilizando microscopia eletrônica de varredura. Foram avaliados 40 bulbos oculares de 20 equinos. Os bulbos oculares foram divididos em quatro grupos (G1, G2, G3 e G4), nos quais: G1 foi composto por 10 botões corneais acondicionados em meio de preservação para córnea Eusol-C® durante sete dias; o G3 foi formado por 10 botões corneais acondicionados em meio de preservação para córnea Eusol-C® durante 14 dias. O G2 e G4 foram formados pelas córneas controle armazenadas imediatamente em glutaraldeído. A média da perda celular observada no G1 foi de 7,62%, no G2 foi de 7,04 %, no G3 foi de 9,12% e o no G4 foi de 7,16%. Não foram observadas diferenças estatisticamente significativas entre os quatro grupos. Foi possível concluir que o meio de preservação hipotérmico Eusol-C® proporcionou de forma satisfatória a preservação do endotélio da córnea na espécie equina durante o período de até 14 dias.(AU)

Effects of atracurium besylate on corneal endothelium of chickens: in vitro study / Avaliação dos efeitos do besilato de atracúrio no endotélio corneano de galinhas: estudo in vitro

The aim of this study was to investigate the acute effects of atracurium besylate on cellular damage in corneal endothelium of chickens. Twenty healthy chicken eyes were assigned to the following groups: Group 1 (G1), experimental group (n=10); and Group 2 (G2), control (n=10). Excised corneoscleral buttons were immediately placed on glass microscopy slides with endothelial region faced up. Corneal endothelium of eyes in G1 were covered with AB (0.2mL, 10mg/mL) for 3 min and then rinsed with balanced salt solution (BSS), while the corneal endothelium of eyes in G2 were covered with BBS for 3 min. Corneas from both groups were stained with alizarin red/trypan blue and visualized by light microscopy. Ten random photographs were taken from each cornea. The area of cellular damage was measured by software in all samples and cell loss of each group was averaged and compared. Endothelial area of denudation and Descemet's membrane exposure were higher in G1 than G2. In conclusion, atracurium besylate induced an acute damage on corneal endothelium of chickens.(AU)'

Objetivou-se avaliar os efeitos agudos do besilato de atracúrio sobre o endotélio corneano de galinhas. Vinte olhos saudáveis de galinhas foram aleatoriamente separados em dois grupos com 10 olhos cada, sendo G1 o grupo controle e G2 o grupo tratamento. Imediatamente após a excisão dos botões corneoesclerais estes foram colocados em lâminas de microscopia de vidro com o lado endotelial voltado para cima. No Grupo 1, o endotélio corneano foi recoberto com 0,2ml de besilato de atracúrio (10mg/ml) durante 3 minutos e depois lavado com solução salina balanceada. No Grupo 2, o endotélio corneano foi recoberto apenas com solução salina balanceada durante 3 min. As córneas de ambos os grupos foram coradas com vermelho de alizarina e azul de tripano e visualizadas com microscópio óptico. Foram obtidas dez fotografias aleatórias de cada amostra. As imagens foram analisadas e com auxílio de um software as áreas com ausência de células endoteliais calculadas. A perda celular endotelial foi significativamente maior no grupo tratamento comparativamente ao grupo controle. Com base nos resultados apresentados foi possível concluir que o besilato de atracúrio induziu dano agudo nas células do endotélio da córnea de galinhas.(AU)

Effects of atracurium besylate on corneal endothelium of chickens: in vitro study / Avaliação dos efeitos do besilato de atracúrio no endotélio corneano de galinhas: estudo in vitro

The aim of this study was to investigate the acute effects of atracurium besylate on cellular damage in corneal endothelium of chickens. Twenty healthy chicken eyes were assigned to the following groups: Group 1 (G1), experimental group (n=10); and Group 2 (G2), control (n=10). Excised corneoscleral buttons were immediately placed on glass microscopy slides with endothelial region faced up. Corneal endothelium of eyes in G1 were covered with AB (0.2mL, 10mg/mL) for 3 min and then rinsed with balanced salt solution (BSS), while the corneal endothelium of eyes in G2 were covered with BBS for 3 min. Corneas from both groups were stained with alizarin red/trypan blue and visualized by light microscopy. Ten random photographs were taken from each cornea. The area of cellular damage was measured by software in all samples and cell loss of each group was averaged and compared. Endothelial area of denudation and Descemet's membrane exposure were higher in G1 than G2. In conclusion, atracurium besylate induced an acute damage on corneal endothelium of chickens.(AU)'

Objetivou-se avaliar os efeitos agudos do besilato de atracúrio sobre o endotélio corneano de galinhas. Vinte olhos saudáveis de galinhas foram aleatoriamente separados em dois grupos com 10 olhos cada, sendo G1 o grupo controle e G2 o grupo tratamento. Imediatamente após a excisão dos botões corneoesclerais estes foram colocados em lâminas de microscopia de vidro com o lado endotelial voltado para cima. No Grupo 1, o endotélio corneano foi recoberto com 0,2ml de besilato de atracúrio (10mg/ml) durante 3 minutos e depois lavado com solução salina balanceada. No Grupo 2, o endotélio corneano foi recoberto apenas com solução salina balanceada durante 3 min. As córneas de ambos os grupos foram coradas com vermelho de alizarina e azul de tripano e visualizadas com microscópio óptico. Foram obtidas dez fotografias aleatórias de cada amostra. As imagens foram analisadas e com auxílio de um software as áreas com ausência de células endoteliais calculadas. A perda celular endotelial foi significativamente maior no grupo tratamento comparativamente ao grupo controle. Com base nos resultados apresentados foi possível concluir que o besilato de atracúrio induziu dano agudo nas células do endotélio da córnea de galinhas.(AU)

Morphology of endothelial cells from different regions of the swine cornea

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-monthold, 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.[...]

Morphology of endothelial cells from different regions of the swine cornea

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-monthold, 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.[...](AU)

Conjunctival melanoma in a horse treated by tumor resection and cryotherapy

Background: Ocular melanoma is very rare compared to cutaneous melanoma in horses. Definitive diagnosis is made through histopathological examination and treatment options include surgical excision associated with cryotherapy, radiation therapy, and chemotherapy. In this report, we describe a case of conjunctival melanoma in a horse that has been treated successfully with surgical excision associated with cryotherapy.Case: A 15-year-old male Percheron male was referred to the Ophthalmology Veterinary Section of the Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil, with a history of a pigmented mass located on the lower eyelid of the left eye. Ophthalmologic examination revealed ocular discomfort, secretion and a pigmented mass in the left inferior bulbar conjunctiva. The dermatological examination revealed other melanomas in the perineal region. Complete blood count and serum chemistry profile were within normal ranges and prior to surgery the horse was treated with flunixin meglumine (1.1 mg/kg, IV, q 12 h). Sedation was performed with xylazine (0.4 mg/kg, IV) and detomidine hydrochloride (0.01 mg/kg, IV) and then the animal was placed in a retention trunk. The conjunctival mass was resected with a margin of safety. Liquid nitrogen was applied to the tumor site and the adjacent conjunctiva with a copper cryoprobe with one unit of liquid nitrogen. Histopathological examination revealed neoplastic cells containing pigmented melanocytes in the conjunctival submucosa, confirming the diagnosis of conjunctival melanoma. Postoperative treatment was performed with flunixin meglumine (1.1 mg/kg, IV, q 12 h) for 3 days and topical ophthalmic ointment containing neomycin, polymyxin B sulfate and dexamethasone twice daily for one week. Seven days after surgery, the lesion was healed. The patient was followed for 24 months after excision and there was no evidence of recurrence.[...](AU)