Antiscarring effect of intraoperative bevacizumab in experimental glaucoma filtration surgery / Efeito antifibrótico do uso intraoperatório de bevacizumab em cirurgia filtrante experimental

ABSTRACT Purpose: To determine the effects of bevacizumab and mitomycin C alone and in combination on intraocular pressure and the scarring process after modified glaucoma filtration surgery in rabbits. Methods: The rabbits underwent modified glaucoma filtration surgery and were allocated into three groups to receive intraoperative treatment with subconjunctival bevacizumab (group A), mitomycin C and subconjunctival bevacizumab (group B), or mitomycin C (group C). Intraocular pressure was measured immediately preoperatively and on postoperative days 8, 14, 17, 21, 26, and 30. The scarring process was assessed 30 days after surgery by tissue section using hematoxylin and eosin, Masson's trichrome, and picrosirius. Expression of vascular endothelial growth factor (VEGF) was assessed by immunohistochemical analyses. All analyses were performed by a masked observer. Results: Animals in group A had higher intraocular pressure than those in groups B and C (p<0.01). Intraocular pressure did not differ significantly between groups B and C. The amount of fibrosis was similar with all stains used: group A had the highest level of fibrosis compared with groups B and C (p>0.05). There was less VEGF expression in group A than in groups B and C (p<0.01). Groups B and C did not differ in VEGF expression. Conclusion: Mean intraocular pressure and fibrosis were lower in animals receiving bevacizumab in combination with mitomycin C but did not differ from values in animals receiving mitomycin C alone. Inhibition of VEGF was greater when bevacizumab was used alone than when bevacizumab was combined with mitomycin C.

RESUMO Objetivo: Determinar os efeitos do bevacizumab, combinados ou não à mitomicina C (MMC), na pressão intraocular e processo cicatricial pós-cirurgia filtrante anti-glaucomatosa modificada em coelhos. Métodos: Os coelhos foram submetidos à cirurgia filtrante anti-glaucomatosa modificada e alocados em três grupos de acordo com o tratamento instituído - Grupo A: bevacizumab subconjuntival; Grupo B: bevacizumab subconjuntival e à mitomicina C ; Grupo C: à mitomicina C. A pressão intraocular foi aferida no período pré-operatório imediato e nos dias 8, 14, 17, 21, 26 e 30. O processo cicatricial foi avaliado no trigésimo dia de pós-operatório por meio de análise histopatológica utilizando-se hematoxilina eosina, tricrômio de Masson e picrosirius. A expressão do fator de crescimento do Endotélio Vascular (VEGF) foi avaliada por meio de análise imuno-histoquímica. Todas as análises foram feitas por um observador mascarado. Resultados: O Grupo A apresentou maior pressão intraocular que os grupos B e C (p<0.01). Não foram encontradas alterações significativas entre os grupos B e C. A quantidade de fibrose encontrada nos grupos foi similar com os 3 corantes utilizados: o Grupo A apresentou maior nível de fibrose em relação aos grupos B e C (p>0,05). Houve menor expressão de Fator de Crescimento do Endotélio Vascular no Grupo A em relação aos grupos B e C (p<0,01). Não houve diferença estatisticamente significante na expressão de Fator de Crescimento do Endotélio Vascular entre os grupos B e C. Conclusão: O bevacizumab associado à MMC apresentou pressões intraoculares mais baixas e menos fibrose, mas estes não foram estatisticamente significantes quando comparados ao uso da mitomicina C isolada. Uma maior inibição do fator de crescimento do endotélio vascular foi encontrada quando o bevacizumab foi usado isoladamente, em detrimento do seu uso associado à mitomicina C.

Antiscarring effect of intraoperative bevacizumab in experimental glaucoma filtration surgery.

PURPOSE: To determine the effects of bevacizumab and mitomycin C alone and in combination on intraocular pressure and the scarring process after modified glaucoma filtration surgery in rabbits. METHODS: The rabbits underwent modified glaucoma filtration surgery and were allocated into three groups to receive intraoperative treatment with subconjunctival bevacizumab (group A), mitomycin C and subconjunctival bevacizumab (group B), or mitomycin C (group C). Intraocular pressure was measured immediately preoperatively and on postoperative days 8, 14, 17, 21, 26, and 30. The scarring process was assessed 30 days after surgery by tissue section using hematoxylin and eosin, Masson's trichrome, and picrosirius. Expression of vascular endothelial growth factor (VEGF) was assessed by immunohistochemical analyses. All analyses were performed by a masked observer. RESULTS: Animals in group A had higher intraocular pressure than those in groups B and C (p<0.01). Intraocular pressure did not differ significantly between groups B and C. The amount of fibrosis was similar with all stains used: group A had the highest level of fibrosis compared with groups B and C (p>0.05). There was less VEGF expression in group A than in groups B and C (p<0.01). Groups B and C did not differ in VEGF expression. CONCLUSION: Mean intraocular pressure and fibrosis were lower in animals receiving bevacizumab in combination with mitomycin C but did not differ from values in animals receiving mitomycin C alone. Inhibition of VEGF was greater when bevacizumab was used alone than when bevacizumab was combined with mitomycin C.

Hypoxia-inducible factor-1α and its role in the proliferation of retinoblastoma cells.

In order to better understand the role of HIF-1α in the proliferation of the retinoblastoma cells, a siRNA knockdown of HIF-1α followed by a proliferation assay was performed. Further sequencing was then carried out in order to assess knockdown efficiency and expression of HIF-1α. Upregulation of HIF-1α gene expression in CoCl2-treated retinoblastoma cells was demonstrated via melting curve analysis from PCR tests and was further analyzed using western blot and densitometry analysis. Reduction of HIF-1α expression in retinoblastoma, post HIF-1α knockdown, was observed after siRNA transfection into Y-79 cells. Knockdown of HIF-1α resulted in a significant decrease in proliferation thereby demonstrating that HIF-1α is involved in promoting survival and proliferation in retinoblastoma cells. Stabilization of HIF-1α in retinoblastoma cells using CoCl2 was unsuccessful.

Local chemotherapeutic agents for the treatment of ocular malignancies.

We critically analyze available peer-reviewed literature, including clinical trials and case reports, on local ocular cancer treatments. Recent innovations in many areas of ocular oncology have introduced promising new therapies, but, for the most part, the optimal treatment of ocular malignancies remains elusive.

Corneal stromal dystrophies: a clinical pathologic study / Distrofia corneana estromal: um estudo clínicopatológico

INTRODUCTION: Corneal dystrophy is defined as bilateral and symmetric primary corneal disease, without previous associated ocular inflammation. Corneal dystrophies are classified according to the involved corneal layer in superficial, stromal, and posterior dystrophy. Incidence of each dystrophy varies according to the geographic region studied. PURPOSE: To evaluate the prevalence of stromal corneal dystrophies among corneal buttons specimens obtained by penetrating keratoplasty (PK) in an ocular pathology laboratory and to correlate the diagnosis with patient age and gender. METHODS: Corneal button cases of penetrating keratoplasty from January-1996 to May-2009 were retrieved from the archives of The Henry C. Witelson Ophthalmic Pathology Laboratory and Registry, Montreal, Canada. The cases with histopathological diagnosis of stromal corneal dystrophies were stained with special stains (Peroxid acid Schiff, Masson trichrome, Congo red analyzed under polarized light, and alcian blue) for classification and correlated with epidemiological information (age at time of PK and gender) from patients' file. RESULTS: 1,300 corneal buttons cases with clinical diagnose of corneal dystrophy were retrieved. Stromal corneal dystrophy was found in 40 (3.1%) cases. Lattice corneal dystrophy was the most prevalent with 26 cases (65%). Nineteen were female (73.07%) and the PK was performed at average age of 59.3 years old. Combined corneal dystrophy was found in 8 (20%) cases, 5 (62.5%) of them were female and the average age of the penetrating keratoplasty was 54.8 years old. Granular corneal dystrophy was represented by 5 (12.5%) cases, and 2 (40%) of them were female. Penetrating keratoplasty was performed at average age of 39.5 years old in granular corneal dystrophy cases. Macular corneal dystrophy was present in only 1 (2.5%) case, in a 36 years old female. CONCLUSION: Systematic histopathological approach and evaluation, including special stains in all stromal corneal dystrophies is critical to establish the correct diagnosis.

INTRODUÇÃO: A distrofia corneana é definida como doença primária da córnea, bilateral e simétrica, sem associação com inflamação ocular prévia. Distrofias corneanas são classificados de acordo com a camada corneana envolvida em distrofia superficial, estromal e posterior. A incidência de cada distrofia varia de acordo com a região geográfica estudada. OBJETIVO: Avaliar a prevalência de distrofias corneanas estromal em botões corneanos de espécimes obtidos por ceratoplastia penetrante (CP), oriundos do arquivo de um laboratório de patologia ocular e correlacionar o diagnóstico com a idade e o sexo dos pacientes. MÉTODOS: Os botões corneanos oriundos de ceratoplastia penetrante recebidos entre janeiro de 1996 e maio de 2009 foram selecionados dos arquivos do Henry C. Witelson Ocular Pathology and Registry Laboratory, em Montreal, Canadá. Os casos com diagnóstico histopatológico de distrofias corneanas estromal foram corados com colorações especiais ("Peroxid acid Schiff", tricrômico de Masson, vermelho Congo analisadas sob luz polarizada, e "alcian blue") para a classificação e foram correlacionados com dados epidemiológicos (idade na época da ceratoplastia penetrante e sexo) dos pacientes. RESULTADOS: 1.300 casos de botões corneanos com diagnóstico clínico de distrofia corneana foram recuperados. Distrofia corneana estromal foi encontrada em 40 (3,1%) dos casos. Distrofia corneana lattice foi a mais prevalente com 26 casos (65%). Dezenove eram do sexo feminino (73,07%) e CP foi realizada em média com 59,3 anos de idade. Distrofia corneana combinada foi encontrada em 8 (20%) casos, 5 (62,5%) eram do sexo feminino e a idade média da CP foi de 54,8 anos. Distrofia corneana granular foi encontrada em 5 (12,5%) casos, e 2 (40%) deles eram do sexo feminino. A ceratoplastia penetrante foi realizada na média de idade de 39,5 anos, em casos de distrofia corneana granular. A distrofia corneana macular esteve presente em apenas um caso (2,5%), 36 anos de idade do sexo feminino. CONCLUSÃO: A abordagem histopatológica e avaliação sistemáticas, incluindo colorações especiais em todas as distrofias corneanas é essencial para estabelecer o correto diagnóstico.

Corneal stromal dystrophies: a clinical pathologic study.

INTRODUCTION: Corneal dystrophy is defined as bilateral and symmetric primary corneal disease, without previous associated ocular inflammation. Corneal dystrophies are classified according to the involved corneal layer in superficial, stromal, and posterior dystrophy. Incidence of each dystrophy varies according to the geographic region studied. PURPOSE: To evaluate the prevalence of stromal corneal dystrophies among corneal buttons specimens obtained by penetrating keratoplasty (PK) in an ocular pathology laboratory and to correlate the diagnosis with patient age and gender. METHODS: Corneal button cases of penetrating keratoplasty from January-1996 to May-2009 were retrieved from the archives of The Henry C. Witelson Ophthalmic Pathology Laboratory and Registry, Montreal, Canada. The cases with histopathological diagnosis of stromal corneal dystrophies were stained with special stains (Peroxid acid Schiff, Masson trichrome, Congo red analyzed under polarized light, and alcian blue) for classification and correlated with epidemiological information (age at time of PK and gender) from patients' file. RESULTS: 1,300 corneal buttons cases with clinical diagnose of corneal dystrophy were retrieved. Stromal corneal dystrophy was found in 40 (3.1%) cases. Lattice corneal dystrophy was the most prevalent with 26 cases (65%). Nineteen were female (73.07%) and the PK was performed at average age of 59.3 years old. Combined corneal dystrophy was found in 8 (20%) cases, 5 (62.5%) of them were female and the average age of the penetrating keratoplasty was 54.8 years old. Granular corneal dystrophy was represented by 5 (12.5%) cases, and 2 (40%) of them were female. Penetrating keratoplasty was performed at average age of 39.5 years old in granular corneal dystrophy cases. Macular corneal dystrophy was present in only 1 (2.5%) case, in a 36 years old female. CONCLUSION: Systematic histopathological approach and evaluation, including special stains in all stromal corneal dystrophies is critical to establish the correct diagnosis.

Eyelid and conjunctival paracoccidioidomycosis simulating carcinoma.

Paracoccidioidomycosis (PCM) is the most prevalent systemic mycosis in immunocompetent individuals in Brazil. Ocular infection by PCM is rare; however, when infection does occur, the most common ocular sites involved are eyelid and conjunctiva. A 68-year-old white male presented with a 2-month history of a painless, ulcerated, infiltrative and diffuse whitish lesion located on the right inferior eyelid. A clinical diagnosis of malignant tumor, possibly squamous cell carcinoma, was made. The histopathologic examination showed a hyperplastic epithelium with inflammatory infiltrate of lymphocytes, plasma cells, neutrophils and histiocytes. Large numbers of giant cells were also present. Periodic acid Schiff and Grocott (silver methenamine) stains showed several large round structures with peripheral lateral small budding cells that resembled a "ship's wheel". No multinucleated fungi were seen. The fungi varied in size and small forms were round and single fungal structures. A diagnosis of paracoccidioidomycosis was made PCM eyelid infection is rare and can simulate carcinoma both clinically and histopathologically.

Melanocytoma of ciliary body and choroids simulating melanoma.

Melanocytoma is a rare intraocular tumor. There are some reports in the literature dealing with primary melanocytomas of the choroid and ciliary body. It is believed that most of these tumors are clinically diagnosed as nevi or melanoma, and are followed up or treated without surgical resection, respectively. Some clinical features can give a clue as to the correct diagnosis. We report on a 47-year-old white female with progressive visual loss of 2 months and right painful eye. Her visual acuity of finger counting was confined to 3.0m OD and 20/20 OS. Biomicroscopy OD showed a 360 degrees posterior synechia, and fundoscopy was not conclusive due to vitreous opacity. No alterations were seen on OS. Intraocular pressure was normal, and the pupillary reflex was present in both eyes. An ultrasound of the OD showed an elevated tumor on topography of the ciliary body and anterior choroid at the ora serrata level. Melanoma was the main diagnosis considered, and enucleation was indicated due to poor prognosis for visual acuity. Gross and histopathologic examinations of the OD showed a heavily pigmented tumor. The brownish pigment obscured the morphology of the tumor cells that could not be visualized by conventional H&E stain. Bleached slides showed that tumor was composed of melanocytoma cells type I.