Despigmentação precoce em caso de ceratopigmentação / Early depigmentation in case of keratopigmentation

RESUMO A ceratopigmentação teve seu primeiro registro pelo filósofo Galeno há muitos séculos como uma estratégia utilizada para o tratamento estético de pacientes com leucomas. As córneas com leucoma são patológicas e, muitas vezes, intolerantes a lentes de contato cosméticas ou próteses oculares, sendo comum a queixa de desconforto excessivo, proporcionado pela superfície corneana irregular. Assim, a ceratopigmentação é uma alternativa para a melhora estética de pacientes com opacidades corneanas. Descrevemos o caso de um paciente do sexo masculino, 39 anos, que apresentou despigmentação precoce em caso de ceratopigmentação associado a quadro de ceratite herpética necrotizante. O paciente foi submetido ao tratamento com aciclovir 2g ao dia e doxiciclina 200mg ao dia, evoluindo com melhora do quadro clínico, apesar da má adesão medicamentosa.

ABSTRACT Keratopigmentation was first recorded many centuries ago by the philosopher Galeno, as a strategy used for the aesthetic treatment of patients with leukomas. Corneas with leucoma are pathological and often intolerant of cosmetic contact lenses or ocular prostheses, with complaints of excessive discomfort provided by the irregular corneal surface being common. Therefore, keratopigmentation is an alternative for the aesthetic improvement of patients with corneal opacities. We describe the case of a 39-year old male patient, who presented early depigmentation in a case of keratopigmentation associated with necrotizing herpetic keratitis. The patient was treated with Acyclovir 2g/day and Doxycycline 200mg/day, evolving with clinical improvement, despite poor medication adherence.

Corneal angiogenesis based on different protocols of alkaline cauterization in murine models

Abstract Purpose: To establish and compare protocols of alkaline cauterization for inducing corneal angiogenesis in murine models. Methods: Twenty-four adult Wistar rats were distributed into four groups (G1, G2, G3, and G4). The right eye cornea from each rat was cauterized using filter paper (3 mm), soaked in a solution of silver and potassium nitrates (3:1). Cauterization times were 10 (G1 and G4), or 20 seconds (G2 and G3). Cauterized corneas were washed with Ringer's lactate solution. The filter paper was either removed before washing (G1 and G2), or kept on the corneas (G3 and G4). Corneas were photographed at multiple time points (2, 4, 6, 8, 11, 13, and 15 days after the procedure), and neovascularization parameters were assayed. Results: Neovascularization was observed in 66% of G1 corneas, and 100% of G2, G3, and G4 corneas. On day 15, G1 corneas showed smaller vascularized areas (12.63 ± 12.59%) compared to those in the G3 (41.95 ± 17.32%) and G4 (33 ± 11.74%) (P < 0.05) groups. Conclusions: The silver and potassium nitrate solution effectively induced corneal angiogenesis. The G2, G3, and G4 protocols showed excellent reproducibility, and induced vascularization in 100% of corneas.

Ação do bevacizumabe subconjuntival na neovascularização e re-epitelização corneana 25 dias após queimadura química / Effect of subconjunctival bevacizumab on corneal neovascularization and reepithelization 25 days after chemical burn

OBJETIVOS: Avaliar a ação do bevacizumabe subconjuntival em modelo experimental de neovascularização em córnea de coelho. Analisar se o modelo de avaliação empregado é adequado e comparar entre os grupos a extensão dos vasos, inflamação e re-epitelização da córnea. MÉTODOS: Estudo experimental, prospectivo em 20 coelhos submetidos a trauma químico com hidróxido de sódio a 1 N divididos em dois grupos, Imediatamente após a queimadura, o grupo tratado recebeu injeção subconjuntival de 0,15 ml (3,75 mg) de bevacizumabe e o grupo controle, injeção subconjuntival de 0,15 ml de soro fisiológico a 0,9 por cento. Após 25 dias, foi realizada análise fotográfica digital para avaliar a extensão e inflamação/calibre dos vasos segundo critério pré-estabelecido e estudo histopatológico da córnea, no qual foi avaliado o estado do epitélio e o número de polimorfonucleares. RESULTADOS: A extensão dos neovasos corneanos foi menor no grupo estudo em relação ao controle (p<0,001). Não houve diferença significativa entre os grupos na inflamação/calibre dos vasos. A análise histopatológica mostrou que não ocorreu diferença entre os grupos nas variáveis estado do epitélio e número de polimorfonucleares. A análise de concordância para a variável extensão dos vasos e para a variável inflamação/calibre dos vasos teve uma estimativa do coeficiente de Kappa respectivamente de 0,705 e 0,500 indicando bom grau de concordância nas diferentes avaliações cegadas, validando o método empregado. CONCLUSÕES: O modelo de avaliação foi adequado e pode ser reproduzido para avaliar outras drogas na córnea. O bevacizumabe inibiu a neovascularização corneana, porém não foi eficaz em reduzir o processo inflamatório. A droga não atrasou a re-epitelização da córnea.

PURPOSES: To evaluate the effect of subconjunctival bevacizumab in an experimental model of neovascularization in rabbit cornea. Determine its effect on vessels extension, inflammation, epithelialization of the cornea and whether the evaluation method used is appropriate to compare neovascular models. METHODS: Experimental, prospective, randomized, blinded study in twenty rabbits subjected to chemical trauma with sodium hydroxide at 1N divided into two groups. The study group received subconjunctival injection of 0.15 ml (3.75 mg) of bevacizumab and was compared with the control group that received subconjunctival injection of 0.15 ml saline solution. After 25 days, digital photographic analysis was performed to assess the vessel's extension and inflammation/diameter according to pre-established criteria. Histopathology of the cornea, which evaluated the state of the epithelium and the number of polymorphonuclear cells was also studied. RESULTS: The length of the neovessels was greater in the control group compared to the study group (P=<0.001). There was no difference in inflammation/vessel diameter between groups. Histopathology analysis showed that there was no difference between groups for the variables state of the epithelium and number of polymorphonuclear cells. The concordance analysis for the variable extension of the vessels and the variable inflammation/vessel diameter was estimated with Kappa coefficients of 0.705 and 0.500 respectively, indicating a good level of agreement in different evaluations and validating the method. CONCLUSIONS: The experimental model is adequate and can be reproduced to evaluate other drugs in the cornea. Bevacizumab inhibit the neovessels' growth but was not effective in preventing the inflammatory response. The drug did not delay the reepithelialization of the cornea.

A Case of Crystalline Keratopathy in Monoclonal Gammopathy of Undetermined Significance (MGUS)

A 62-year-old female visited our clinic with progressively decreased vision in both eyes beginning 12 years prior. Idiopathic corneal opacity in all layers of the cornea was found in both eyes. One year later, we performed penetrating keratoplasty on the undiagnosed right eye. During post-surgical follow-up, corneal edema and stromal opacity recurred, and penetrating keratoplasty was performed two more times. The patient's total serum protein level, which had previously been normal, was elevated prior to the final surgery. She was diagnosed with monoclonal gammopathy of undetermined significance. We made a final diagnosis of monoclonal gammopathy-associated crystalline keratopathy after corneal biopsy. Monoclonal gammopathy-associated crystalline keratopathy is difficult to diagnose and may lead to severe visual loss. A systemic work-up, including serologic tests like serum protein or cholesterol levels, is needed in patients with unexplainable corneal opacity.

The effect of subconjunctival bevacizumab on corneal neovascularization, inflammation and re-epithelization in a rabbit model

PURPOSE: To evaluate the use of subconjunctival bevacizumab on corneal neovascularization in an experimental rabbit model for its effect on vessel extension, inflammation, and corneal epithelialization. METHODS: In this prospective, randomized, blinded, experimental study, 20 rabbits were submitted to a chemical trauma with sodium hydroxide and subsequently divided into two groups. The experimental group received a subconjunctival injection of bevacizumab (0.15 m; 3.75 mg), and the control group received an injection of 0.15 ml saline solution. After 14 days, two blinded digital photograph analyses were conducted to evaluate the inflammation/diameter of the vessels according to pre-established criteria. A histopathological analysis of the cornea evaluated the state of the epithelium and the number of polymorphonuclear cells. RESULTS: A concordance analysis using Kappa's statistic showed a satisfactory level of agreement between the two blinded digital photography analyses. The neovascular vessel length was greater in the control group (p<0.01) than in the study group. However, the histopathological examination revealed no statistically significant differences between the groups in terms of the state of the epithelium and the number of polymorphonuclear cells. CONCLUSIONS: Subconjunctival bevacizumab inhibited neovascularization in the rabbit cornea. However, this drug was not effective at reducing inflammation. The drug did not induce persistent corneal epithelial defects.

Lymphangiogenesis occurring in transplanted corneas / 华中科技大学学报（医学）（英德文版）

To study corneal lymphangiogenesis after corneal transplantation, corneal allogenic transplantation models were established in rats. 8 female Wister rats were used as donors, and 16 Sprague Dawley (SD) rats were used as recipients and 2 SD served as controls. Corneal lymphangiogenesis and hemangiogenesis was examined by electron microscopy 1 and 2 weeks after corneal penetrating transplantation, and the expression of lymphatic vessel endothelial receptor (LYVE-1) was examined 1, 3, 7, 14 days after the transplantation respectively. In addition, 19 allograft failed human corneas were examined by 5'-nase-alkaline phosphatase (5'-NA-ALP) double-enzyme-histochemistry staining to detect corneal lymphangiogenesis and hemangiogenesis. By immunohistochemistry for LYVE-1, it was found that blown lymphatics were localized in the stroma 3 days after the corneal transplantation. With electron microscopy, new lymphatic vessels and blood vessels were found 1 and 2 weeks after the corneal transplantation. By 5'-NA-ALP enzyme-histochemistry, corneal hemangiogenesis was found in all allograft failed human corneas and 5 of 19 (26.3 %) cases had developed corneal lymphangiogenesis. It is concluded that corneal lymphangiogenesis is present after corneal transplantation, which may play an important role in allograft rejection.

Treatment of corneal neovascularization with argon laser

Corneal neovascularization, which is associated with complications in corneal diseases, can cause lipid deposit, decreasing vision, and graft rejection after penetrating keratoplasty (PKP). Corneal laser photocoagulation using an argon laser or yellow dye laser for ablation of corneal neovascularization has been described. We performed corneal argon laser photocoagulation (CALP) in two male patients with corneal neovascularization after herpetic keratitis. One PKP was performed after CALP and restored good vision with no rejection of the graft during an 8 month follow-up period. In the other case we observed visual improvement and no recurrence of corneal neovascularization after CALP.