Retinal changes in rabbit after intravitreal injection of sunitinib encapsulated into solid lipid nanoparticles and polymeric nanocapsules / Avaliação das alterações retinais no coelho após injeção intravítrea de sunitinib encapsulado em nanoparticulas lípidas sólidas e nanocapsulas polímeros

ABSTRACT Purpose: We aimed to evaluate the safety of single intravitreal injection of each of two concentrations of 0.1 ml of sunitinib (1 and 10 mg/ml), 0.1 ml of a drug-free dispersion containing solid lipid nanoparticles, and 0.1 ml of a drug-free dispersion containing polymeric nanocapsules for analyzing the possible toxic effects using electrophysiology and histology in albino rabbit retina. Methods: We conducted an experimental controlled study of 20 eyes of albino rabbits. Intravitreal injections of each specific agent were applied to one eye per rabbit in each 5-rabbit group, while the contralateral eyes received no treatment and were used as controls. Results: We noted no electroretinographic changes in the sunitinib (1 and 10 mg/ml) or in solid lipid nanoparticles groups. However, we observed significant abnormalities in ocular morphology and in the electroretinogram in the nanocapsules group. At the histological level, only the nanocapsules group demonstrated abnormal changes, including severe edema and cytoplasmic vacuole formation. Conclusions: While nanocapsules intravitreal injections indicated retinal toxic effects, sunitinib and solid lipid nanoparticles intravitreal injections were not toxic to the retina. Our results suggest that a sunitinib preparation with solid lipid nanoparticles for controlled release may offer a significant therapeutic approach for vasoproliferative ocular disease.

RESUMO Objetivos: O presente estudo teve por objetivo avaliar a segurança da injeção intravítrea de 0,1 ml de sunitinibe em duas concentrações (1 mg/ml e 10 mg/ml), 0,1 ml de dispersão contendo nanopartículas lipídicas sólidas sem droga e 0,1 ml de dispersão contendo nanocápsulas poliméricas livre de drogas analisando os possíveis efeitos tóxicos à retina de coelhos albinos detectados pela eletrofisiologia e histologia por microscopia óptica. Métodos: Um estudo controlado experimental foi rea­lizado com 20 olhos de coelhos albinos. Foram realizadas injeções intravítrea de duas concentrações diferentes de suniti­nibe, uma dispersão contendo nanopartículas lipídicas sólidas e uma dispersão contendo nanocápsulas. O olho contralateral não recebeu tratamento e foi utilizado como controle. Resultados: Não foram observadas alterações eletrorretinográficas nos grupos do sunitinibe (1 mg/ml e 10 mg/ml) e no grupo das nanopartículas lipídicas sólidas. No grupo das nanocápsulas, houve alterações significativas tanto na morfologia, quanto na amplitude e tempo das ondas do eletrorretinograma. Ao estudo histológico, somente o grupo das nanocápsulas apresentou al­terações degenerativas (núcleos tumefeitos) com acentuado edema e formação de vacúolos citoplasmáticos, sugerindo toxidade retiniana. Conclusões: As injeções intravítreas de sunitinibe e nanopartículas lipídicas sólidas não foram tóxicas para a retina. No entanto, nanocápsulas mostraram ser tóxicas para a retina. Sendo assim, a possibilidade de poder combinar o potencial de uma droga que possui a capacidade de inibir duas importantes vias da angiogênese, às vantagens de liberação controlada das nanopartículas lipídicas sólidas, pode ser um importante recurso terapêutico para doenças vasoproliferativas oculares.

Retinal toxicity due to hydroxychloroquine: frequency in an Ophthalmology ambulatory / Toxicidade retiniana pela hidroxicloroquina: frequência em um ambulatório de Oftalmologia

Abstract Hydroxychloroquine is widely used by rheumatologists for the treatment of various diseases, such as systemic lupus erythematosus and rheumatoid arthritis because of its safety and low cost. However, it can cause retinal abnormalities. Until today, there is no Brazilian protocol for screening for retinal changes in these patients. We reviewed the medical records and optical coherence tomography of all patients who had attended at Hychloroquine Ambulatory of HFSE, in the period from March/ 2015 until November/2016.

Resumo A Hidroxicloroquina é amplamente utilizada por reumatologistas para o tratamento de várias condições, como os lúpus eritematoso sistêmico e artrite reumatoide, pelo seu baixo custo e relativa segurança. Porém, esta droga pode causar danos à retina. Até o presente momento, não há protocolo brasileiro para o screening de alterações retinianas devido ao uso desta medicação. Foi realizada revisão de prontuário e análise de imagens de tomografia de coerência óptica de pacientes atendidos no período de Março de 2015 a Novembro de 2016 no ambulatório de Hidroxicloroquina do Hospital Federal dos Servidores do Estado do Rio de Janeiro.

Effects of caffeic acid phenethyl ester on retinal damage after traumatic brain injury / Efectos del ester fenetílico del ácido cafeico en el daño de la retina después de una lesion cerebral traumática

SUMMARY: Head trauma damages the optic nerve visual function and visual acuity.Effects of head trauma on the retina was investigated with biochemical, histological and immunohistochemical respects.The study was conducted on 30 rats with three groups: group 1 was control group (n=10). Second group was head-traumatized group (n=10) and last group was head-traumatized+Caffeic acid phenethyl ester (CAPE, i.p. 20ml/kg/day). Upon head was traumatized, CAPE was applied to trauma+CAPE group and then for the following four days. At the end of 5th day, rats were anesthetized with ketamine hydroxide and then blood samples were taken for biochemical analysis. MDA and GSH-Px values were compared. After blood sample, total eyes of rats were dissected for histopathological and immunohistochemical analysis. In trauma group, degeneration in retinal photoreceptor cells, disintegrity and in inner and outer nuclear layers, hypertrophy in ganglion cells, and hemorrhage in blood vessels were observed. In the group treated with CAPE, lesser degeneration in photoreceptor cells, regular appearances of inner and outer nuclear layers, mild hemorrhage in blood vessels of ganglionic cell layer were observed. The apoptotic changes caused by trauma seen in photoreceptor and ganglionic cells were decreased and cellular organization was preserved due to CAPE treatment. CAPE was thought to induce healing process on traumatic damages.

RESUMEN: El trauma craneal daña la función visual del nervio óptico y la agudeza visual. Se investigaron los efectos del traumatismo craneal en la retina con aspectos bioquímicos, histológicos e inmunohistoquímicos. El estudio se realizó en 30 ratas distribuidas en tres grupos: grupo control (n = 10); grupo con traumatismo craneal (n = 10); grupo con traumatismo craneoencefálico + Éster fenetílico de ácido cafeico (CAPE, i.p. 20 ml / kg / día). Sobre la cabeza traumatizada, se aplicó CAPE a trauma + grupo CAPE durante los siguientes cuatro días. Al final del día 5, las ratas se anestesiaron con hidróxido de ketamina y luego se tomaron muestras de sangre para el análisis bioquímico. Se compararon los valores de MDA y GSH-Px. Después de la muestra de sangre, se disecaron los ojos de las ratas para su análisis histopatológico e inmunohistoquímico. En el grupo de traumatismos, se observó degeneración en las células fotorreceptoras retinianas, desintegridad en capas nucleares internas y externas, hipertrofia en células ganglionares y hemorragia en los vasos sanguíneos. En el grupo tratado con CAPE, se observó una menor degeneración en las células fotorreceptoras, apariciones regulares de capas nucleares internas y externas, hemorragia leve en los vasos sanguíneos de la capa de células ganglionares. Los cambios apoptóticos causados por el trauma visto en el fotorreceptor y las células ganglionares disminuyeron y la organización celular se conservó debido al tratamiento con CAPE. Se concluyó que CAPE induce un proceso de curación en daños traumáticos.

Intravitreal injection of polysorbate 80: a functional and morphological study / Injeção intravítrea de polissorbato 80: estudo funcional e morfológico

ABSTRACT Objective : to determine the functional and morphological effects at rabbits retina of PS80 concentration used in the preparation of intravitreal drugs. Methods: eleven New Zealand rabbits received a intravitreal injection of 0.1ml of PS80. As control, the contralateral eye of each rabbit received the same volume of saline. Electroretinography was performed according to a modified protocol, as well as biomicroscopy and retina mapping before injection and seven and ten days after. Animals were euthanized in the 30th day and the retinas were analyzed by light microscopy. Results: eyes injected with PS80 did not present clinical signs of intraocular inflammation. Electroretinography did not show any alteration of extent and implicit time of a and b waves at scotopic and photopic conditions. There were no morphological alterations of retinas at light microscopy. Conclusion: intravitreal injection of PS80 in the used concentration for intravitreal drug preparations do not cause any functional or morphological alterations of rabbit retinas. These results suggest that PS80 is not toxic to rabbit retinas and may be safely used in the preparation of new lipophilic drugs for intravitreal injection.

RESUMO Objetivo: determinar os efeitos funcionais e morfológicos na retina de coelhos da concentração de PS80 utilizada na preparação de drogas intravítreas. Métodos: onze coelhos New Zealand receberam injeção intravítrea de 0,1ml de PS80. Como controle, o olho contralateral de cada coelho recebeu o mesmo volume de soro fisiológico. Foram realizados eletrorretinogramas de acordo com o protocolo modificado, biomicroscopia e mapeamento de retina antes da injeção, sete e dez dias depois. Os animais foram sacrificados no 30o dia e as retinas analisadas por microscopia de luz. Resultados: os olhos injetados com PS80 não apresentaram sinais clínicos de inflamação intraocular. O eletrorretinograma não apresentou alteração de amplitude e tempo implícito das ondas a e b nas condições escotópica e fotópica. Não houve alteração morfológica da retina na microscopia de luz. Conclusão: a injeção intravítrea de PS80 na concentração utilizada na preparação de drogas intravítreas não causa alterações funcionais e morfológicas na retina de coelhos. Esses resultados sugerem que o PS80 não é tóxico para a retina de coelhos e pode ser usado com segurança na preparação de novas drogas lipofílicas para injeção intravítrea.

Effects of Potentilla fulgens on the changes made in the retinal damage induced by traumatic head injury / Efectos de Potentilla fulgens en los cambios producidos debido al daño retinal inducido por lesión traumática en la cabeza

Traumatic head injury is a leading cause of mortality and morbidity. As a result of head trauma occurring in the retina of the various biochemical, histological and immunohistochemical effects were investigated. Sprague­Dawley rats were subjected to traumatic brain injury with a weight-drop device using 300 g-1 m weight­height impact. Twenty one rats were divided into three groups, as group 1 (vehicle-treated control), group 2 (vehicle-treated trauma) group 3 trauma + Potentilla fulgens ( P. Fulgens) 400 mg/kg/day, i.p.). Distilled water was used as vehicle. All rats were decapitated 5 days after the induction of trauma, and the protective effects of P. Fulgens were evaluated by histological, immunohistochemical and biochemical analyses. Although further studies are necessary to evaluate the time-and dose-dependent neuroprotective effects of P. Fulgens. Depending on whether trauma inhibits apoptosis of photoreceptor cells, ganglion cells, it is thought that the the support against the degeneration of neural connections can be considered. This study indicates that P.Fulgens is potentially useful for the treatment of eye disorders induced by traumatic brain injury.

El trauma de cráneo es una de las principales causas de morbilidad y mortalidad. Como resultado de un traumatismo craneal, la retina puede sufrir diversos efectos bioquímicos, histológicos e inmunohistoquímicos. Veintiún ratas Sprague-Dawley fueron sometidas a lesión craneal traumática con un dispositivo, de caída de peso, usando un impacto de 300 g-1 m de peso-altura. Las ratas fueron divididas en tres grupos: grupo 1 (control), grupo 2 (traumatismo) y grupo 3 trauma + Potentilla fulgens (400 mg / kg / día, i. p.). Se usó agua destilada como vehículo en todos los grupos. Las ratas fueron decapitadas 5 días después de la inducción del trauma, y se evaluaron los efectos protectores de P. Fulgens mediante análisis histológicos, inmunohistoquímicos y bioquímicos. Es necesario realizar más estudios para evaluar los efectos neuroprotectores, dependientes del tiempo y la dosis, de P. Fulgens. Dependiendo si el trauma inhibe la apoptosis de las células fotorreceptoras, se estima que la disposición de las células ganglionares ayuda contra la degeneración de las conexiones neuronales. P. Fulgens ha demostrado ser efectivo para el tratamiento de los trastornos oculares inducidos por lesión cerebral traumática.

Rabdomiólisis grave secundaria a deshidratación hipernatrémica / Severe rhabdomyolysis secondary to severe hypernatraemic dehydration

Introducción: La rabdomiólisis es una enfermedad poco frecuente en pediatría. El objetivo es presentar un paciente en el que se desarrolló secundario a una deshidratación hipernatrémica grave tras una diarrea aguda. Caso clínico: Lactante de 11 meses que consultó por fiebre, vómitos, diarrea y anuria. Presentó convulsión tónico-clónica autolimitada. Ingresó en mal estado general, severamente deshidratado, con escasa reactividad. En las pruebas complementarias destacó acidosis metabólica grave, hipernatremia e insuficiencia renal prerrenal. Al tercer día apreció leve hipotonía axial y elevación de creatín fosfokinasa 75.076 UI/l, interpretado como rabdomiólisis. Se inició hiperhidratación y alcalinización sistémica, con buena respuesta clínica y bioquímica, siendo dado de alta sin secuelas motoras. Conclusiones: La hipernatremia grave está descrita como causa rara de rabdomiólisis e insuficiencia renal. En pacientes críticos es importante un alto índice de sospecha de rabdomiólisis y determinación seriada de la creatín fosfokinasa para su detección y tratamiento precoz.

Introduction: Rhabdomyolysis is a rare paediatric condition. The case is presented of a patient in whom this developed secondary to severe hypernatraemic dehydration following acute diarrhoea. Case report: Infant 11 months of age who presented with vomiting, fever, diarrhoea and anuria for 15 hours. Parents reported adequate preparation of artificial formula and oral rehydration solution. He was admitted with malaise, severe dehydration signs and symptoms, cyanosis, and low reactivity. The laboratory tests highlighted severe metabolic acidosis, hypernatraemia and pre-renal kidney failure (Sodium [Na] plasma 181 mEq/L, urine density> 1030). He was managed in Intensive Care Unit with gradual clinical and renal function improvement. On the third day, slight axial hypotonia and elevated cell lysis enzymes (creatine phosphokinase 75,076 IU/L) were observed, interpreted as rhabdomyolysis. He was treated with intravenous rehydration up to 1.5 times the basal requirements, and he showed a good clinical and biochemical response, being discharged 12 days after admission without motor sequelae. Conclusions: Severe hypernatraemia is described as a rare cause of rhabdomyolysis and renal failure. In critically ill patients, it is important to have a high index of suspicion for rhabdomyolysis and performing serial determinations of creatine phosphokinase for early detection and treatment.

Historogical and immunohistochemical study on the effect of Bishenol A on the retina of female albino rat

Background: Bisphenol A [BPA] is a well-known endocrine disruptor used to manufacture polycarbonate plastics and epoxy resins. Exposure of rats to low doses of BPA results in histopathological effects in their retina

Objectives: We used histological and immunohistogical techniques for determining retina pathological changes in response to low doses of BPa and the modulating effect of both vitamin A and stem enhancer

Methods: Twenty female albino rats orally administered with 20mg BPA/kgb.wt/day for 45 days and then divided to groups and treated with vitamin A and stem enhancer. Both eyes were examined histological and immunohistochemicaly to determine the histologically changes in retinal layers

Results: Aremarkable degenerative histopathological changes in the ganglion cell layer and inner nuclear layer appeared with bis phenol treated rats and a clear improvement was seen after the treatment with both vitamin A and stem cell enhancer

Conclusion: Both of vitamin A and stem enhancer have amelorative effect on the degenerative changes in the retinal layers and damaged estrogen receptors by the action of bisphenol A

Brimonidine tartrate effect on retinal spreading depression depends on Müller cells / O efeito do tartarato de brimonidina sobre a depressão alastrante retiniana depende das células de Müller

Objective: Demonstrate the Brimonidine effect over Retinal Spreading Depression (SD). Brimonidine is an alpha-2–adrenergic receptor agonist, used in the management of glaucoma. Alpha2-agonists have been shown to be neuroprotective in various experimental models, however the molecular and cellular targets leading to these actions are still poorly defined. The SD of neuronal electric activity is a wave of cellular massive sustained depolarization that damages the nervous tissue. Local trauma, pressure, ischemic injuries and other chemical agents as high extracellular potassium concentration or glutamate, can trigger SD, leading to exaggerated focal electrical followed by an electrical silence. Methods: Using chicken retina as model, we performed alpha2-receptor detection by Western Blotting and Immunohistochemistry. After that we obtained electrical signals of SD by microelectrodes on retina in the absence or presence of Brimonidine. For in vivo visualization we observed retina with optical coherence tomography on normal state, with SD passing, and with SD + Brimonidine. Results: Our data demonstrated that: (1) alpha2-adrenergic receptors are present in Müller cells, (2) the treatment with Brimonidine decreases the SD‘s velocity as well as the voltage of SD waves and (3) OCT revealed that SD creates a hyper reflectance at inner plexiform layer, but on retinal treatment with brimonidine, SD was not visualized. Conclusions: Our study about brimonidine possible pathways of neuroprotection we observed it reduces SD (a neuronal damage wave), identified a new cellular target – the Müller cells, as well as, firstly demonstrated SD on OCT, showing that the inner plexiform layer is the main optically affected layer on SD. .

Objetivo: Demonstrar o efeito do Tartarato de Brimonidina, um alfa2-agonista usado no manejo do glaucoma, sobre a depressão alastrante (DA) retiniana. Esses agonistas têm demonstrado ser neuroprotetores em vários modelos experimentais, contudo seus alvos celulares e moleculares continuam indefinidos. A DA da atividade elétrica neuronal é uma onda de despolarização celular massiva e sustentada que leva ao dano no tecido nervoso. Trauma local, pressão, isquemia e outros agentes químicos como o aumento do potássio extracelular e o glutamato podem disparar a DA, levando a uma atividade elétrica exagerada seguida de silêncio elétrico. Métodos: Usando a retina de pinto como modelo, realizamos a detecção do alfa2-receptor por Western Blotting e ensaio Imunohistoquímico. Após isso, obtivemos os sinais elétricos da DA através de microeletrodos inseridos na retina durante sua passagem na presença ou ausência de Brimonidina. Para visualização do tecido utilizamos o tomógrafo de coerência optica (OCT), analisando como é a retina no seu estado de repouso, durante a passagem da DA, e a DA + brimonidina. Resultados: Nossos dados demonstraram que: (1) os receptores alfa adrenérgicos presentes na retina são do subtipo-2A e estão localizados nas células de Müller; (2) o tratamento com Brimonidina diminui a velocidade e a voltagem da onda de DA; (3) A OCT demonstrou que a DA retiniana possui um sinal óptico de maior reflectância na camada plexiforme interna, fato não observado quando foi associada à Brimonidina. Conclusão: A Brimonidina foi capaz de reduzir a DA (uma onda de lesão neuronal) e identificamos um novo possível alvo celular – a célula de Müller e demonstramos pela primeira vez uma OCT da DA, visualizando a camada plexiforme interna como a mais afetada opticamente pelo fenômeno. .

Ultra-high resolution optical coherence tomography analysis of bull's eye maculopathy in chloroquine users / Análise da maculopatia em bull's eye pela tomografia de coerência óptica de alta resolução em usuários de cloroquina

Purpose: Register and compare anatomical changes, structural and quantitative found in optical coherence tomography Stratus and Topcon 3D in chronic users of chloroquine. Methods: Five patients were diagnosed with toxic "bull's eye" maculopathy was submitted to macular optical coherence tomography examination (Stratus and Topcon 3D). Results: Both tools demonstrated an increase reflectivity of choriocapillaris unit just foveal retinal pigment epithelium atrophy. However, Topcon 3D provided to all patients better description of the line corresponding to the transition between inner and outer segments of photoreceptors. Using the possibility of assembling threedimensional images and subtraction selective retinal layers, we found a lesion with a target that reflects the greater thickness of retinal pigment epithelium in central and parafoveal region that is matched to preserve macular photoreceptors. Conclusion: it was observed better resolution and faster image capture by Topcon 3D than Stratus OCT, that provided more detailed analysis of the line corresponding to transition between outer and inner segment of photoreceptors in macular region. With Topcon 3D, it was possible to evaluate soundly the thickness of retinal pigment epithelium in central and parafoveal region that caused an increase reflectivity of choriocapillaris creating a image with a target unpublished before. .

Objetivo: Comparar e registrar as alterações quantitativas e qualitavivas na tomografia de coerência óptica nos pacientes com uso prolongado de cloroquina. Métodos: Avaliaram-se cinco pacientes com diagnóstico de bull’s eye no exame de tomografia de coerência óptica macular com dois modelos de aparelhos: Stratus e Topcon 3D. Resultados: Ambos aparelhos registraram aumento da refletividade coriocapilar foveal provocada pela atrofia do epitélio pigmentar da retina. Somente o Topcon 3D permitiu melhor visibilização da linha de transição entre o segmento interno e externo dos fotorreceptores. Este aparelho também permitiu a formação de imagens tridimensionais e subtração das camadas retinianas, com registro da diminuição da espessura do epitélio pigmentado da retina na região central e parafoveal macular. Conclusão: Foi possível observar a captação mais rápida e com melhor resolução das imagens geradas pelo Topcon 3D. A diminuição da espessura do epitélio pigmentado da retina, provocando o aumento da refletividade coriocapilar, com a formação de uma imagem linear circular cincundando a fóvea, foi mais detalhado pelos cortes realizados no Topcon 3D. .

Hip-implant related chorio-retinal cobalt toxicity.

A 39-year-old female with elevated serum cobalt levels from her bilateral hip prostheses presented with a 3-week history of blurred vision in her left eye. Optical coherence tomography revealed patchy degeneration of the photoreceptor-retinal pigment epithelium (RPE) complex. The lesions were hypofluorescent on indocyanine green angiography. We postulate that this is a case of implant-related chorio-retinal cobalt toxicity.

Vitreous pharmacokinetics and electroretinographic findings after intravitreal injection of acyclovir in rabbits

OBJECTIVES: Acute retinal necrosis is a rapidly progressive and devastating viral retinitis caused by the herpesvirus family. Systemic acyclovir is the treatment of choice; however, the progression of retinal lesions ceases approximately 2 days after treatment initiation. An intravitreal injection of acyclovir may be used an adjuvant therapy during the first 2 days of treatment when systemically administered acyclovir has not reached therapeutic levels in the retina. The aims of this study were to determine the pharmacokinetic profile of acyclovir in the rabbit vitreous after intravitreal injection and the functional effects of acyclovir in the rabbit retina. METHODS: Acyclovir (Acyclovir; Bedford Laboratories, Bedford, OH, USA) 1 mg in 0.1 mL was injected into the right eye vitreous of 32 New Zealand white rabbits, and 0.1 mL sterile saline solution was injected into the left eye as a control. The animals were sacrificed after 2, 9, 14, or 28 days. The eyes were enucleated, and the vitreous was removed. The half-life of acyclovir was determined using high-performance liquid chromatography. Electroretinograms were recorded on days 2, 9, 14, and 28 in the eight animals that were sacrificed 28 days after injection according to a modified protocol of the International Society for Clinical Electrophysiology of Vision. RESULTS: Acyclovir rapidly decayed in the vitreous within the first two days after treatment and remained at low levels from day 9 onward. The eyes that were injected with acyclovir did not present any electroretinographic changes compared with the control eyes. CONCLUSIONS: The vitreous half-life of acyclovir is short, and the electrophysiological findings suggest that the intravitreal delivery of 1 mg acyclovir is safe and well tolerated by the rabbit retina.

Tela de Amsler e campo visual no rastreamento da retinopatia por cloroquina / Amsler grid and visual field on screening for chloroquine retinopathy

OBJETIVOS: Comparar a tela de Amsler modificada com o campo visual Humphrey® 10-2 vermelho nos usuários de cloroquina, na detecção da maculopatia precoce, e correlacionar com as variáveis de risco. MÉTODOS: Foram analisados 116 olhos de 58 pacientes, acompanhados no Serviço de Oftalmologia do Hospital do Servidor Público Estadual de São Paulo, entre abril de 2006 e abril de 2008. Todos os usuários tinham fundo de olho normal e mais de dois anos de terapia com cloroquina. Os participantes tiveram seus dados clínicos avaliados e foram submetidos ao exame da acuidade visual corrigida, biomicroscopia de fundo, campimetria macular automatizada e tela de Amsler. RESULTADOS: A incidência da maculopatia precoce foi de 7 a 10%, dependendo do exame considerado. A concordância entre a tela de Amsler e o campo visual foi baixa. Para o grupo de olhos que apresentaram ambos os exames alterados, houve significância estatística com a alta dose diária, dose cumulativa elevada e baixa acuidade visual; a idade do paciente e a duração do tratamento não mostraram boa correlação nestes casos, mas suas médias (67,4 anos e 8,4 anos, respectivamente) situaram-se dentro da faixa dos fatores de alto risco. CONCLUSÕES: O estudo sugere que a tela de Amsler pode ser útil na complementação das informações do campo visual no rastreamento periódico da retinopatia por cloroquina, sobretudo naqueles com fatores de alto risco bem estabelecidos, selecionando melhor os candidatos à realização de testes objetivos, como o OCT de alta resolução e o ERG multifocal.

PURPOSE: To compare the modified Amsler grid to the Humphrey® 10-2 red visual field in chloroquine users for the detection of early maculopathy, and to correlate with the risk variables. METHODS: The study included 116 eyes of 58 patients followed at the Department of Ophthalmology of Hospital do Servidor Público Estadual de São Paulo, from April, 2006 to April, 2008. All users had normal fundus and more than 2 years of chloroquine therapy. Their clinical data were evaluated and they underwent visual acuity examination, fundus biomicroscopy, visual field and Amsler grid. RESULTS: The incidence of early maculopathy was 7 to 10%, depending on the examination considered. The agreement between the Amsler grid and visual field was low. There was statistical significance with the use of high daily dose, elevated cumulative dose and low visual acuity in patients whose eyes had both abnormal tests; patient age and duration of treatment did not show good correlation in these cases, but their averages (67.4 years and 8.4 years, respectively) were within the range of high risk factors. CONCLUSIONS: The study suggests that Amsler can be useful in complementing the information on the visual field for chloroquine retinopathy periodic screening, especially for those patients who present high risk factors well established, selecting better candidates for objective tests, such as HD OCT and mfERG.

Reduced occurrence of programmed cell death and gliosis in the retinas of juvenile rabbits after shortterm treatment with intravitreous bevacizumab

OBJECTIVE: Bevacizumab has been widely used as a vascular endothelial growth factor antagonist in the treatment of retinal vasoproliferative disorders in adults and, more recently, in infants with retinopathy of prematurity. Recently, it has been proposed that vascular endothelial growth factor acts as a protective factor for neurons and glial cells, particularly in developing nervous tissue. The purpose of this study was to investigate the effects of bevacizumab on the developing retinas of juvenile rabbits. METHODS: Juvenile rabbits received bevacizumab intravitreously in one eye; the other eye acted as an untreated control. Slit-lamp and fundoscopic examinations were performed both prior to and seven days after treatment. At the same time, retina samples were analyzed using immunohistochemistry to detect autophagy and apoptosis as well as proliferation and glial reactivity. Morphometric analyses were performed, and the data were analyzed using the Mann-Whitney U test. RESULTS: No clinical abnormalities were observed in either treated or untreated eyes. However, immunohistochemical analyses revealed a reduction in the occurrence of programmed cell death and increases in both proliferation and reactivity in the bevacizumab-treated group compared with the untreated group. CONCLUSIONS: Bevacizumab appears to alter programmed cell death patterns and promote gliosis in the developing retinas of rabbits; therefore, it should be used with caution in developing eyes.

Estudo de toxicidade retiniana após injeções intravítreas seriadas de infliximabe em olhos de coelhos / A safety study of retinal toxicity after serial intravitreal injections of infliximab in rabbits eyes

OBJETIVO: Determinar os níveis de toxicidade de duas e três aplicações intravítreas de infliximabe na retina de coelhos albinos, por meio de exames clínicos oftalmológicos, eletrorretinográficos e histológicos. MÉTODOS: Foram utilizados doze coelhos albinos divididos em dois grupos. No primeiro grupo de 10 coelhos, cada olho recebeu duas (n=10 olhos) ou três injeções (n=10 olhos) intravítreas de 2 mg de infliximabe dissolvidos em 0,06 ml de solução salina, em intervalos mensais. Um segundo grupo de dois coelhos, que serviu como grupo controle (n=4 olhos), foram submetidos a duas e três aplicações intravítreas de BSS. Noventa dias após, os coelhos foram novamente submetidos a exame oftalmológico (biomicroscopia, oftalmoscopia e tonometria), eletrorretinográfico e, após enucleados, a exame histológico. RESULTADOS: O exame biomicroscópico e oftalmoscópico não revelou anormalidades retinianas nos olhos injetados com infliximabe e no grupo controle. Alteração histológica notada foi a presença de raros linfócitos e eosinófilos no vítreo posterior em quatro e em seis olhos submetidos a duas e três aplicações de infliximabe sem significado clínico. A única alteração clinicamente significante foi uma reação inflamatória severa com presença de exsudatos vítreos na interface vítreo retiniana e discreto edema de células ganglionares nos dois olhos de um único coelho, sem alterações no vítreo posterior. Os exames eletrorretinográficos mostraram amplitudes em média 12-13 por cento menores daquelas obtidas antes do tratamento, contudo não houve nenhuma diferença estatisticamente significante quando comparamos as amplitudes e a latencia entre os achados electrorretinográficos pré e pós-tratamento. CONCLUSÃO: Duas e três aplicações intravítreas de infliximabe em olhos de coelhos em intervalos mensais, na dosagem de 2 mg, não provocam alterações significantes após um seguimento de noventa dias, quer no exame histológico, na eletrorretinografia e na avaliação clínica oftalmológica. Conclui-se que doses seriadas de infliximabe por via intravítrea é um procedimento seguro. Estudos clínicos em humanos devem ser realizados para melhor avaliação da segurança do seu uso no tratamento de determinadas doenças que acometem a retina e a coroide.

PURPOSE: To determine retinal and choroid toxicity levels of two and three infliximab intravitreous injections in albino rabbits by means of electroretinographic, histological and ophthalmological clinical tests. METHODS: 12 albino rabbits were used in the study. Each eye was given two (n=10 eyes) or three (n=10 eyes) serial intravitreous 2 mg infliximab injections dissolved in 0.06 ml of saline, at monthly intervals. A separate group of rabbits (n=4 eyes) served as a control group. Ninety days after the study had begun, the rabbits underwent clinical and electroretinographic tests, and after being enucleated, the eyes were examined for histological changes. RESULTS: Slit-lamp biomicroscopy and fundoscopic examination did not reveal any significant retinal abnormalities in the eyes injected with infliximab and control eyes or in pre- and post-treated eyes. The histological change that was noted was the presence of rare lymphocytes and eosinophils in the posterior vitreous of some of the rabbits subjected to two or three injections, but it was not considered clinically significant. A severe inflammatory reaction with vitreous exudates and ganglion cell edema in a single rabbit was clinically significant. The electroretinographic tests showed amplitudes that were on the average 12-13 percent smaller than those obtained before the treatment, however, there were no statistically significant differences when comparing the amplitude or the implicit time between pre- and post-treatment electroretinographic findings. CONCLUSION: Two and three intravitreous 2 mg infliximab injections in rabbits at monthly intervals did not cause any changes after a 90-day follow-up, according to histological and electroretinographic tests and after clinical evaluation. Differently from prior studies that have investigated potential retinotoxicity effects after single administrations, this study investigated the possibility of retinotoxicity after multiple injections. Clinical studies in humans should be conducted to better evaluate the safety of this drug in the treatment of certain diseases affecting the retina and the choroid.

Intravitreal bevacizumab (avastin) for circumscribed choroidal hemangioma.

Circumscribed choroidal hemangiomas are rare ophthalmic entities that cause diminution in vision due to accumulation of subretinal and/or intraretinal fluid in the macular area. Various treatment options ranging from conventional laser to photodynamic therapy have been employed to destroy the tumor and reduce the exudation; however, either the inability to penetrate through the exudative fluid or the collateral retinal damage induced by these treatment modalities make them unsuitable for lesions within the macula. We evaluated the role of intravitreal bevacizumab, a pan-vascular endothelial growth factor (VEGF) inhibitor, in reducing the sub- and intraretinal fluid in three patients with circumscribed choroidal hemangiomas. All the patients had complete resolution of the serous retinal detachment that was maintained till at least 12 months after the first injection. Intravitreal bevacizumab may be used in combination with thermal laser or photodynamic therapy in treating circumscribed choroidal hemangiomas with subretinal fluid.

Retinal nitric oxide and malonyldialdehyde levels following photodynamic therapy.

Background: To determine the retinal nitric oxide (NO) and malonyldialdehyde (MDA) levels following photodynamic therapy (PDT). Materials and Methods: Seven Dutch-belted rabbits received dextrose, while seven others received 2 mg/kg verteporfin infusion over a period of 15 minutes in a dim-lit room. Irradiation to a 1.5 mm diameter intact chorioretinal area in the right eye of verteporfin-infused rabbits, was started 5 minutes after the end of infusion. Three groups were control (dextrose infusion), infusion with verteporfin (left eyes were not irradiated), and irradiation after verteporfin injection (right eyes were irradiated). On the fifth day of the experiment, the eyes were enucleated. The retinas were subsequently frozen and homogenized. Nitrite, a stable end-product of NO and MDA, was measured using the spectrophotometer. Protein concentrations were measured by the Lowry method. Tissue NO and MDA levels were expressed as μmol/gprt and nmol/mgprt, respectively. Results: The mean retinal NO and MDA levels of the control, infusion, and irradiation groups were 24.67 ± 6.66, 0.11 ± 0.02; 45.90 ± 15.52, 0.21 ± 0.09; and 84.43 ± 14.96 μmol/gprt, 0.58 ± 0.14 nmol/mgprt, respectively. The mean retinal NO levels were significantly elevated in the infusion and irradiation groups compared with the control group (P:0.004; P:0.001). The mean retinal MDA levels were significantly elevated in the infusion and irradiation groups compared to the control one (P:0.026; P:0.001). Also the mean retinal NO and MDA levels in the irradiation group were found to be significantly higher than the infusion group (P:0.018; P:0.018). Conclusion: Not only PDT, but also verteporfin infusion alone resulted in NO and MDA level increments in the retina, which might be toxic.

Multifocal Electroretinogram Findings after Intravitreal Bevacizumab Injection in Choroidal Neovascularization of Age-Related Macular Degeneration

PURPOSE: To evaluate the changes in multifocal electroretinogram (mfERG) and optical coherence tomography (OCT) after intravitreal bevacizumab injection in the treatment of age-related macular degeneration (AMD). METHODS: Twenty-one eyes with choroidal neovascularization secondary to AMD were studied before and after intravitreal bevacizumab injection for best corrected visual acuity (BCVA), OCT, and mfERG. RESULTS: The BCVA improved, while central macular thickness and total macular volume in OCT decreased after intravitreal bevacizumab injection (p = 0.03, 0.01, and 0.01, respectively). In mfERG, the amplitude of P1, and implicit time of P1 and N1 indicated a statistically significant improvement of retinal response after intravitreal bevacizumab injection. CONCLUSIONS: There is a potential role for mfERG in evaluating the effect on retinal function of intravitreal bevacizumab injection.

Complicações oculares da terapêutica com a cloroquina e derivados / Ocular complications of chloroquine and derivatives therapy

INTRODUÇÃO: Os derivados das 4-aminoquinolonas vêm sendo utilizados desde sua industrialização na terapêutica da malária, das doenças reumatológicas e dermatológicas. Essas drogas apresentam reações adversas sistêmicas e oculares. As reações adversas sistêmicas afetam o sistema gastrointestinal, sistema nervoso, sistema muscular esquelético e a pele, e as oculares são: fotofobia, córnea verticilata, poliose, catarata, paralisia dos músculos extraoculares, uveíte anterior, maculopatia tóxica, neurite óptica. OBJETIVO: Revisão bibliográfica das complicações do uso de cloroquina e derivados. Analisar evolução e estágio atual da propedêutica. Sugerir conduta prática no mapeamento precoce dos sinais de toxicidade. MÉTODOS: Revisão bibliográfica através da pesquisa no banco de dados MEDLINE, PUBMED, LILACS e SciELO. DISCUSSÃO: São descritos todos os exames que podem ser utilizados para mapeamento das reações adversas oculares, tais quais: exame oftalmológico completo, com ênfase na biomicroscopia e oftalmoscopia binocular indireta, campo visual computadorizado, tela de Amsler, visão de cores, exames eletrofisiológicos, polarimetria e tomografia de coerência óptica. É feita a descrição do quadro de maculopatia enfocando epidemiologia, fatores de risco, histopatologia e propedêutica. É descrita a estrutura química e as diferenças entre os derivados das 4-aminoquinolonas. CONCLUSÃO: Todo paciente em uso de cloroquina e seus derivados devem ser acompanhados e documentados desde seu início e até atingir a dose cumulativa acima de 100 gramas. Quanto maior a dose cumulativa, maior deve ser a nossa preocupação com o seguimento desse paciente.

INTRODUCTION: Byproducts of 4-aminoquinolones are being used since its industrialization in the treatment of malaria, rheumatic and dermatologic diseases. These drugs present systemic and ocular adverse events. Systemic adverse reactions affect the gastrointestinal, nervous and skeletal muscular systems and the skin. Ocular adverse reactions are: photophobia, cornea verticillata, poliosis, cataract, extraocular muscle palsy, anterior uveitis, toxic maculopathy and optical neuritis. PURPOSE: Bibliography review of complications due to the use of chloroquine and its derivatives. To analyze the current practice and propedeutics' evolution. To suggest practical managements for early toxicity signs. METHODS: Bibliographic review through research on MEDLINE, PUBMED, LILACS and SciELO database. DISCUSSION: All exams that can be used to screen ocular adverse reactions are described, such as: complete ophthalmologic exam, with emphasis on biomicroscopy and indirect binocular ophthalmoscopy, computerized visual field, Amsler grid testing and color vision testing, electrophysiological exams, polarimetry and optical coherence tomography. A description of maculopathy is presented, focusing on epidemiology, risk factors, histopathology and propedeutics. Chemical structure and the differences between 4-aminoquinolone derivatives are described. CONCLUSION: All patients using chloroquine and its derivatives must be followed-up and documented since the beginning of the therapy until they reach a cumulative dose above 100 grams. The higher the cumulative dose, the more we must be concerned with patient follow-up.

Retinal Protective Effects of Resveratrol via Modulation of Nitric Oxide Synthase on Oxygen-induced Retinopathy

PURPOSE: Retinopathy of prematurity (ROP) is one of the leading causes of blindness, with retinal detachment occurring due to oxygen toxicity in preterm infants. Recently, advances in neonatal care have led to improved survival rates for preterm infants, and ROP has increased in incidence. In the present study, we aimed to determine whether or not resveratrol exhibits protective effects in an animal model of ROP and in primary retinal cell cultures of neonatal rat via nitric oxide (NO)-modulating actions using western blotting and real-time PCR with inducible nitric oxide synthase (iNOS), endothelial NOS (eNOS) and neuronal NOS (nNOS) antibodies and mRNAs. METHODS: In an in vivo oxygen-induced retinopathy (OIR) model, cyclic hyperoxia was induced with 80% O2 for one day and 21% O2 for one day from P1 to P14 in newborn Sprague-Dawley (SD) rats. Resveratrol was injected intravitreally for seven days and rats were sacrificed at P21. In vitro OIR primary retinal cell culture was performed using P0-2 SD rats. Hyperoxia injuries were induced through 100% O2 exposure for six hours. Western blotting and real-time PCR using iNOS, eNOS, nNOS antibodies and primers were performed in the rat model of ROP and the dispersed retinal cell culture. RESULTS: In both in vivo and in vitro OIR, the expression of iNOS antibody and mRNA was increased and of eNOS and nNOS were reduced in the resveratrol-treated group. CONCLUSIONS: In conclusion, resveratrol appeared to exert retinal protective effects via modulation of NO-mediated mechanism in in vivo and in vitro OIR models.

Estudo experimental da inibição da proliferação vitreorretiniana pelo uso da hiperecina / Experimental study of vitreoretinal proliferation inhibition by the use of hypericin

OBJETIVOS: Induzir a produção de membranas vitreorretinianas em modelo de trauma ocular animal. Avaliar a inibição do desenvolvimento da proliferação vitreorretiniana (PVR) com o uso de hiperecina. MÉTODOS: Estudo Experimental. Foram utilizados 19 coelhos machos pigmentados adultos com peso entre 2.000 e 3.000 gramas. Todos submetidos a modelo de trauma com dispase associada à diatermia da retina para indução de membranas de PVR. Separados randomicamente para receberem hiperecina (10 µM em 0,1 ml) ou solução salina (0,1 ml) como placebo. Avaliados clinicamente no sétimo, décimo quarto, vigésimo primeiro e vigésimo oitavo dias de pós-operatório com oftalmoscopia indireta e retinografia colorida digitalizada. O grau de PVR foi classificado em estágios (de 0 a 7) segundo Hida e colaboradores. RESULTADOS: A formação de membranas esteve presente em 79 por cento dos olhos, sendo 100 por cento nos olhos do grupo placebo e 60 por cento nos olhos do grupo tratamento (hiperecina). A comparação entre as médias dos estágios de PVR entre os grupos mostrou diferença estatisticamente significativa, com valor p=0,0321 pelo teste Wilcoxon. CONCLUSÕES: O modelo de trauma com uso de dispase e diatermia da retina produz membranas vitreorretinianas. A hiperecina mostrou-se eficaz na diminuição do aparecimento e progressão do PVR.

PURPOSE: To produce proliferative vitreoretinopathy (PVR) in an animal ocular trauma model. To evaluate the inhibition of (PVR) emergence and progression by hypericin. METHODS: Experimental Study. Nineteen pigmented male adult rabbits weighing between 2,000 and 3,000 grams were used in this study. All of them were submitted to trauma model with dispase and retinal diathermy to induce PVR membranes formation. They were randomly assigned to receive hypericin (10 µM in 0.1 ml) or saline solution (0.1 ml) as placebo. They were evaluated clinically in the seventh, fourteenth, twenty-first and twenty-eighth postoperative days with indirect ophthalmoscopy and digital color retinography. The PVR degree was classified according to Hida (0 to 7). RESULTS: Membranes formation was present in 79 percent of the eyes; being 100 percent in the eyes of placebo group and 60 percent in the eyes of treatment group (hypericin). The comparison between PVR phases averages within the groups showed a statistically significant difference between the two groups, with a p value of 0.0321 for Wilcoxon test. CONCLUSIONS: The trauma model with dispase and retinal diathermy produces vitreoretinal membranes. Hypericin was considered effective in PVR emergence and progression decrease.