Glucocorticoids are known to affect metabolic activities of cells. The mechanism of glucocorticoid actions in adult human dermal and mouse L-929 fibroblasts have yet to be fully ascertained. This study endeavors to examine the effects of one glucocorticoid, triamcinolone acetonide, on cellular proliferation and collagen synthesis and to compare such effects in the human and mouse cell lines. Cellular proliferation and collagen synthesis are analyzed and quantitated by cell counts and selective digestion of the protein by bacterial collagenase, respectively. Further analysis of collagen synthesis is provided by polyacrylamide gel electrophoresis. One-tenth triamcinolone acetonide per ml suppresses cellular proliferation of mouse L-929 fibroblasts. Proline incorporation into total and collagenase-sensitive protein is enhanced in the cell layer; that of medium is altered inconsistently. Polyacrylamide gel electrophoresis of proteins treated with pepsin show the abolition of total and collagenase-sensitive protein in the cell layer. Aberrations in hydroxylation and/or deformation in physical structure of protein may confer greater susceptibility to pepsin digestion. Cellular proliferation and proline incorporation into total and collagenase-sensitive protein of adult human dermal fibroblasts are affected inconsistently by the same dose of triamcinolone acetonide. Except for the consistent suppression of cellular proliferation in the murine L-929 fibroblasts by triamcinolone acetonide, all observations pertaining to human dermal fibroblasts are incompatible with those obtained by other workers. Manipulation of culture conditions and glucocorticoid treatment dictate, to a large extent, the kind of responses observed. This could account for the wide variability and frequent contradictory findings reported in the literature. / Pharmaceutical Sciences, Faculty of / Graduate

Zheng Tingting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 98-124). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.iv / Table of Contents --- p.vi / List of Tables --- p.viii / List of Figures --- p.ix / Abbreviations --- p.xi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Triamcinolone acetonide(TA) --- p.1 / Chapter 1.1.1 --- Application in ophthalmology --- p.1 / Chapter 1.1.2 --- Mechanism of anti-inflammatory effect --- p.2 / Chapter 1.1.3 --- Side effects of TA --- p.4 / Chapter 1.1.4 --- Toxicity of TA --- p.5 / Chapter 1.2 --- Retinal pigment epithelial (RPE) cell --- p.6 / Chapter 1.3 --- Mechanism of cell death --- p.8 / Chapter 1.3.1 --- Apoptosis --- p.9 / Chapter 1.3.2 --- caspase --- p.11 / Chapter 1.3.3 --- Mitogen-activated protein kinase (MAPK) --- p.13 / Chapter 1.3.4 --- Activator Protein-1 (AP-1) --- p.15 / Chapter 1.4 --- Potassium channel (K+）） --- p.15 / Chapter 1.4.1 --- Molecular structure of KAtp channel --- p.16 / Chapter 1.4.2 --- Regulation of Katp channel --- p.17 / Chapter 1.4.3 --- Pinacidil --- p.18 / Chapter 1.5 --- Calcium channel --- p.20 / Chapter 1.5.1 --- VDCCs and subtypes --- p.21 / Chapter 1.5.2 --- Calcium channel blocker --- p.22 / Chapter 1.5.3 --- Verapamil --- p.23 / Chapter 1.6 --- Study objectives --- p.25 / Chapter Chapter 2 --- Methodology --- p.37 / Chapter 2.1 --- Cell biology --- p.37 / Chapter 2.1.1 --- Materials --- p.37 / Chapter 2.1.1.1 --- Culture related material --- p.37 / Chapter 2.1.1.2 --- Drugs --- p.37 / Chapter 2.1.1.3 --- Cell line and instrument --- p.37 / Chapter 2.1.2 --- Preparations --- p.38 / Chapter 2.1.2.1 --- Working medium --- p.38 / Chapter 2.1.2.2 --- Drugs --- p.38 / Chapter 2.1.2.3 --- MTT solution --- p.39 / Chapter 2.1.3 --- Cell culture and treatment process --- p.40 / Chapter 2.1.3.1 --- Seed cell --- p.40 / Chapter 2.1.3.2 --- Treatment --- p.40 / Chapter 2.1.4 --- MTT-Cell Proliferation Assay --- p.41 / Chapter 2.2 --- Molecular biology --- p.42 / Chapter 2.2.1 --- Materials --- p.42 / Chapter 2.2.1.1 --- "Chemicals, reagents, and kits" --- p.42 / Chapter 2.2.1.2 --- Solutions and Buffers --- p.42 / Chapter 2.2.1.3 --- Primers and Enzymes --- p.43 / Chapter 2.2.1.4 --- Equipment --- p.43 / Chapter 2.2.1.5 --- Software --- p.43 / Chapter 2.2.2 --- Reverse transcription 226}0ؤ Polymerase Chain Reaction (RT-PCR) --- p.44 / Chapter 2.2.2.1 --- Cell collection and RNA Isolation --- p.44 / Chapter 2.2.2.2 --- Reverse Transcription (RT) --- p.45 / Chapter 2.2.2.3 --- PCR Reaction --- p.46 / Chapter 2.3 --- Immunocytochemistry --- p.48 / Chapter 2.3.1 --- Materials and instrumentation --- p.49 / Chapter 2.3.1.1 --- Antibodies and Equipment --- p.49 / Chapter 2.3.1.2 --- Chemicals and other useful items --- p.49 / Chapter 2.3.2 --- Preparations --- p.50 / Chapter 2.3.2.1 --- Preparation of coverslips --- p.50 / Chapter 2.3.2.2 --- Prepations of solutions --- p.50 / Chapter 2.3.3 --- Procedures --- p.51 / Chapter 2.4 --- Expression of results and statistics --- p.52 / Chapter Chapter 3 --- Results --- p.57 / Chapter 3.1 --- Effects of TA on RPE cell culture --- p.57 / Chapter 3.1.1 --- Cell morphology --- p.57 / Chapter 3.1.2 --- MTT assay --- p.57 / Chapter 3.1.3 --- Gene expressions --- p.57 / Chapter 3.2 --- Effects of PIN/VP on TA treated RPE cells --- p.58 / Chapter 3.2.1 --- MTT assay --- p.58 / Chapter 3.2.2 --- Gene expression --- p.59 / Chapter 3.2.2.1 --- Expression of housekeeping gene --- p.59 / Chapter 3.2.2.2 --- Expression of apoptosis-related gene --- p.59 / Chapter 3.2.2.3 --- Expression of early-response genes --- p.60 / Chapter 3.2.3 --- Immunofluorescence --- p.61 / Chapter Chapter 4 --- Discussion --- p.86 / Chapter Chapter 5 --- References --- p.98

Objetivo: Avaliar a eficiência da Triancinolona Acetonida como agente modulador da resposta inflamatória e cicatricial em coelhos submetidos a cirurgia de músculo extra-ocular. Método: Foi realizado estudo prospectivo, mascarado, em dois estádios. No primeiro estádio, dez coelhos foram submetidos a retrocesso do músculo reto superior em ambos os olhos. Aplicouse, em um deles, 0,15 cc de Triancinolona Acetonida (40mg/cc) nos tecidos circunjacentes ao local de reinserção muscular e, como controle, 0,15cc de solução de cloreto de sódio a 0,9% no local equivalente no olho contra-lateral. Quinze dias após, cinco coelhos foram submetidos a exenteração das órbitas e os restantes dos animais tiveram o mesmo procedimento realizado após trinta dias. O material do sítio de reinserção muscular foi avaliado por meio de análise histopatológica qualitativa e quantitativa (morfometria). No segundo estádio, com incrementação da agressão cirúrgica, dezesseis coelhos foram submetidos aos mesmos procedimentos com exenteração das órbitas após quinze dias, e posterior análise histopatológica dos tecidos. Resultados: Houve efeito inibitório sobre a intensidade da resposta inflamatória nos olhos tratados em comparação com os olhos controle. Conclusão: Nas condições de realização do presente estudo o uso per-operatório da triancinolona acetonida foi efetivo no controle da resposta inflamatória em olhos de coelhos submetidos a cirurgia de músculo extra-ocular. / Purpose: To evaluate the efficiency of triamcinolone acetonide (TRI) in limiting the postoperative inflammatory response and scarring following strabismus surgery. Methods: A prospective, two-stage, masked, controlled trial was conducted. In the first stage, the inflammatory response at the extraocular reattachment site was analyzed following superior rectus recession in ten rabbits. One eye had 0,15 cc of triamcinolone acetonide (40mg/cc) applied around the new insertion site and, similarly, 0,15 cc of isotonic saline solution (0,9%) was applied to the fellow eye following the same procedure, thus serving as a control. Fifteen days later, orbital exenteration was performed in five rabbits and the remaining five were exenterated thirty days later. The reattachment site tissues were submitted to qualitative and quantitative histological examinations. In the second stage 16 rabbits were submitted to amplified surgical trauma, after which the aforementioned steps were also carried out. Granuloma total area at the extraocular muscle reattachment sites of control and treated eyes were compared. Results: There was an inhibitory effect of TRI on the inflammatory response of treated eyes as compared to control eyes. Conclusions: TRI was effective in controlling the postoperative inflammatory response in rabbit eyes submitted to traumatic recession of the superior rectus muscle.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 126-143).

Objetivo: Avaliar a eficiência da Triancinolona Acetonida como agente modulador da resposta inflamatória e cicatricial em coelhos submetidos a cirurgia de músculo extra-ocular. Método: Foi realizado estudo prospectivo, mascarado, em dois estádios. No primeiro estádio, dez coelhos foram submetidos a retrocesso do músculo reto superior em ambos os olhos. Aplicouse, em um deles, 0,15 cc de Triancinolona Acetonida (40mg/cc) nos tecidos circunjacentes ao local de reinserção muscular e, como controle, 0,15cc de solução de cloreto de sódio a 0,9% no local equivalente no olho contra-lateral. Quinze dias após, cinco coelhos foram submetidos a exenteração das órbitas e os restantes dos animais tiveram o mesmo procedimento realizado após trinta dias. O material do sítio de reinserção muscular foi avaliado por meio de análise histopatológica qualitativa e quantitativa (morfometria). No segundo estádio, com incrementação da agressão cirúrgica, dezesseis coelhos foram submetidos aos mesmos procedimentos com exenteração das órbitas após quinze dias, e posterior análise histopatológica dos tecidos. Resultados: Houve efeito inibitório sobre a intensidade da resposta inflamatória nos olhos tratados em comparação com os olhos controle. Conclusão: Nas condições de realização do presente estudo o uso per-operatório da triancinolona acetonida foi efetivo no controle da resposta inflamatória em olhos de coelhos submetidos a cirurgia de músculo extra-ocular. / Purpose: To evaluate the efficiency of triamcinolone acetonide (TRI) in limiting the postoperative inflammatory response and scarring following strabismus surgery. Methods: A prospective, two-stage, masked, controlled trial was conducted. In the first stage, the inflammatory response at the extraocular reattachment site was analyzed following superior rectus recession in ten rabbits. One eye had 0,15 cc of triamcinolone acetonide (40mg/cc) applied around the new insertion site and, similarly, 0,15 cc of isotonic saline solution (0,9%) was applied to the fellow eye following the same procedure, thus serving as a control. Fifteen days later, orbital exenteration was performed in five rabbits and the remaining five were exenterated thirty days later. The reattachment site tissues were submitted to qualitative and quantitative histological examinations. In the second stage 16 rabbits were submitted to amplified surgical trauma, after which the aforementioned steps were also carried out. Granuloma total area at the extraocular muscle reattachment sites of control and treated eyes were compared. Results: There was an inhibitory effect of TRI on the inflammatory response of treated eyes as compared to control eyes. Conclusions: TRI was effective in controlling the postoperative inflammatory response in rabbit eyes submitted to traumatic recession of the superior rectus muscle.

Glucocorticoids (GCs) have been widely used as a therapeutic agent for diverse inflammatory ocular diseases. However, a high percentage of patients undergoing this treatment develop high intraocular pressure (IOP), which if left unsupervised may lead to glaucoma. It is believed that the IOP elevation in response to GC treatment has a genetic determinant. In order to test this hypothesis, we analyzed in 52 patients the presence of single nucleotide polymorphisms (SNPs) in the glucocorticoid receptor gene (GR), the principal mediator of GCs uptake by the cells. We studied six GR SNPs previously reported to be associated with sensitivity and resistance to GCs: GluArg22/23GluLys (codon 22-23), Asn363Ser (codon 363), IVS2+646C>G (intron 2/BclI), IVS3-46G>C (intron 3), IVS4-16G>T (intron 4), Asn766Asn (Codon 766). Nevertheless, the results of this preliminary study did not show any specific correlation between SNPs in the GR gene and IOP elevation. Therefore, we proceeded to perform a whole genome SNP screen with the DNA samples of these patients to search for possible target genes responsible for the elevated IOP after GC treatment. As a result, we identified forty-eight SNPs in thirty-three genes that correlate with the high IOP response. The gene showing the strongest association is a poorly known G-protein coupled receptor. In addition, four SNPs hit a single transporter gene. Other candidate genes identified are a translation elongation factor, an F-box protein, an oxysterol binding protein, and a solute carrier family gene. These results support our hypothesis that IOP elevation following GC treatment is a genetically determined response. GCs are a common treatment for innumerable medical conditions; we believe that a genetic association between GC treatment and its physiological response may be important for improving treatment management and drug development for retinal diseases as well as for other medical ailments. However, further studies need to be performed to analyze in depth the association between the candidate genes identified in this study and the steroid response.

In this study, it is aimed to develop an injectable controlled release system of PCL and P(L,DL)LA microspheres loaded with TA and/or Ral for local treatment of rheumatoid arthritis which will avoid from systemic side effects of traditional administration and eliminate problems caused by direct local injections. Rheumatoid arthritis (RA) is a chronic, systemic, autoimmune disorder that most commonly causes inflammation and tissue damage in joints and tendon sheaths. Current strategies for the disease are mainly towards relieving symptoms and increasing mobility. The microsphere form drug delivery systems were developed to enhance the treatment success of rheumatic diseases by providing these agents alone or together for long terms without causing systemic or local site effects upon injection to the RA joints. Microspheres were prepared with s/o/w solvent evaporation technique and optimized to achieve a suitable size for joint application, to sustain the delivery of the drug(s), to provide required amount of the agent with feasible amount of microsphere. In order to manage these, microspheres prepared with different combinations of polymers and drugs were examined for particle size analysis, surface and structural characterizations, time related drug release properties, and drug loading capacities. In vitro cytotoxicity tests using 3T3 fibroblast cells were done to evaluate the biocompatibility of drug loaded PCL microspheres. The degradation of polymers were conducted and evaluated by GPC analysis. In PCL:TA microspheres, as polymer:drug ratio decreased (from 10:1 towards 10:4), namely as the drug partition increased, it was seen that encapsulation efficiency and loading percentages increased. Meanwhile, percent release of the drug decreased, indicating more prolonged release. Among all microspheres, PCL:TA 10:4 and PCL:Ral 10:2 were found to be the most appropriate for dual release in terms of release values (ca 21% and 0.09%, respectively), loadings (ca 27% and ca 13%, respectively) and mean particle size values (ca 100 &mu / m and ca 95 &mu / m, respectively). After release studies, microspheres preserved their sphericity. These selected polymer:drug groups also represented no cytotoxic effect. The microspheres for dual drug study (PCL:TA:Ral 10:4:2) released app. 55% of its TA and 0.29% of Ral at the end of 4 weeks. Drug loading capacities of these microspheres were found to be ca 14% for TA and 8% for Ral. Furthermore, with dual loading case, smallest mean particle size (68 &mu / m) could be obtained among all studied groups. P(L,DL)LA microspheres caused high viscosity problems during microsphere preparation steps and resulted in the slowest release, which was unfavorable for the aim of the study. To our knowledge there is no microsphere study reported with P(L,DL)LA in literature. The TA and Ral delivery systems with PCL and P(L,DL)LA were developed and studied for the first time in literature and they were optimized for RA treatment purposes. The potential of these systems, should be further tested in experimental animal models of RA.

[pt] Os glicocorticóides sintéticos tais como a triancinolona acetonido e a prednisolona não possuem fluorescência natural e nem são induzidos a fluorescer por meio do procedimento padrão para glicocorticóides naturais, que consiste no tratamento com ácido sulfúrico concentrado. No presente trabalho, um procedimento de derivação fotoquímica para triancinolona acetonido e prednisolona foi desenvolvido e cuidadosamente otimizado com o intuito de se obter derivados fluorescentes estáveis que permitiram elaborar um método espectrofluorimétrico para determinação dos mesmos em formulações farmacêuticas. Este procedimento consistiu na exposição à radiação ultravioleta (300 nm) de soluções ácidas dos glicocorticóides sintéticos em reator fotoquímico. Parâmetros experimentais, tais como tipo e concentração do ácido, temperatura e tempo de aquecimento, sistema de solventes e tempo de exposição ao UV se mostraram críticos e por isso foram cuidadosamente estudados. As características do reator também se mostraram importantes para o sucesso do procedimento. A intensidade da fluorescência (excitação em 240 nm e emissão em 350 nm) e a estabilidade dos fotoprodutos se mostraram apropriados para permitir o desenvolvimento de um método espectrofluorimétrico. Parâmetros instrumentais importantes, tais como banda espectral de passagem e a velocidade de varredura foram otimizados, visando à obtenção da melhor razão sinal do analito/sinal do branco e da melhor resolução espectral. Parâmetros analíticos de mérito, obtidos a partir das curvas analíticas, revelaram limites de detecção de 5 e 6 ng mL-1 para triancinolona acetonido e prednisolona, respectivamente; e limites de quantificação de 17 ng mL-1 para a triancinolona acetonido e 19 ng mL-1 para a prednisolona. As faixas lineares dinâmicas, nos dois casos, se estenderam por três ordens de grandeza com coeficientes de linearidade (r2) de 0,99. Este método espectrofluorimétrico foi testado em formulações farmacêuticas, obtendo-se os melhores resultados para os comprimidos e soluções injetáveis. Estudos para avaliar o efeito de dois potenciais interferentes (polimixina B e benzocaína) também foram realizados. Resultados de recuperação foram avaliados tomando como referência os valores indicados na bula do medicamento e também valores obtidos com o procedimento de referência (HPLC com detecção fotométrica UVvis) utilizado no Jockey Club Brasileiro, obtendo resultados entre 97 ± 14 e 104 ± 6 %. / [en] The synthetic glucocorticoid such as triamcinolone acetonide and prednisolone neither present natural fluorescence nor fluorescence can be induced by means of the standard procedure used for natural glucocorticoids which consists on a treatment with concentrated sulfuric acid. In the present work, a photochemical derivatization procedure for these two synthetic glucocorticoids was developed and carefully optimized aiming the obtantion of fluorescent derivatives stable enough to allow the development of a spectrofluorimetric method for determination of these analytes in pharmaceutical formulations. The photochemical derivatization procedure consisted on the exposure of acidic solutions of these synthetic glucocorticoids to the ultraviolet radiation (300 nm) in a photochemical reactor. Experimental parameters such as type and concentration of the acid, temperature and heating time, solvent system and UV exposition time have shown to be critical and therefore they were carefully studied. The design of the photochemical reactor) has also shown to be relevant for the success of the procedure. The intensity of the fluorescence (with maximum excitation and emission wavelenghts at 240 nm and 350 nm respectively) and the stability of these photoproducts, have shown to be appropriated for the development of a spectrofluorimetric method. Important instrumental parameters such as spectral bandpass and scan velocity have been optimized aiming the achievement of best signal-to-blank ratio and spectral resolution. Analytical parameters of merit, obtained from the analytical curve, have indicated limits of detention of 5 and 6 ng mL-1 for triamcinolone acetonide and prednisolone, respectively, and limits of quantification of 17 ng mL-1 for triamcinolone acetonide and 18 ng mL-1 for prednisolone. The linear dynamic range for both analytes extended over three orders of magnitude with linear coefficients (r2) of 0,99. The spectrofluorimetric method was tested by the analysis of pharmaceutical formulations, with best performance for tablets and injectable solutions. A study to evaluate the effect of two potential interferents (polimixine B and benzocaine) has also been made. Recovery results were evaluated using both, the reference values indicated in the medicine instructions and concentration values obtained using the reference procedure (HPLC with UV-visible photometric detection) used in the Brazilian Jockey Club. Satisfactory recovery results were achieved (between 97 ± 14 and 104 ± 6 %).

INTRODUÇÃO: O edema macular difuso é uma importante causa de baixa visual em portadores de diabetes mellitus. O tratamento clássico deste tipo de retinopatia consiste na fotocoagulação, entretanto, esta terapêutica é ineficaz em muitos casos. Neste trabalho, avaliou-se a eficácia do uso intravítreo da triancinolona acetonida associada à fotocoagulação com laser de argônio no tratamento do edema macular difuso diabético. Esta associação terapêutica foi comparada com o uso isolado de cada tratamento. MÉTODOS: Neste estudo, realizado entre junho de 2005 e setembro de 2006, foram estudados 30 pacientes diabéticos clinicamente controlados e portadores de edema macular difuso. Estes pacientes foram alocados de forma aleatória e proporcional em um dos seguintes grupos de tratamento: (1) fotocoagulação macular em grade com laser de argônio; (2) aplicação intravítrea de 4 mg de triancinolona acetonida; (3) associação dos itens anteriores. O seguimento foi realizado em intervalos pré-determinados de um dia, uma semana e mensalmente, até completar 6 meses. Foram analisados os parâmetros: acuidade visual corrigida LogMAR; espessura macular central e volume macular total medido pela tomografia de coerência óptica; e pressão intra-ocular aferida pelo tonômetro de Goldmann. RESULTADOS: A fotocoagulação com laser não reduziu de forma estatisticamente significativa a espessura macular central (p=0,0862) e o volume macular total (p=0,11). Esta redução foi significativa e estatisticamente semelhante nos outros dois grupos (p<0,001). Todos os grupos apresentaram melhora da acuidade visual (p=0,003), entretanto, o grupo que recebeu a associação do laser com a triancinolona intravítrea, obteve maior percentagem de pacientes com ganho de 10 ou mais letras de visão no quarto e quinto mês de seguimento (p=0,026; p=0,034). A pressão intra-ocular elevou-se em 5 mmHg ou mais em 12 pacientes, sendo seis no grupo submetido apenas a triancinolona e os outros seis no grupo que recebeu a associação de tratamento (p<0,001).Todos estes casos foram bem controlados com colírio de maleato de timolol 0,5%. CONCLUSÕES: O uso simultâneo da fotocoagulação com a triancinolona intravítrea proporcionou maior ganho de linhas de visão do que o uso isolado de cada tratamento. A fotocoagulação com laser foi a única terapia que não reduziu de forma significativa a espessura e o volume macular total e, também, foi a única que não apresentou casos de hipertensão ocular durante o seguimento. / INTRODUCTION: The diffuse macular edema is an important cause of visual impairment in diabetic subjects. Laser photocoagulation is the main treatment for this disorder, however, it is not effective in a large number of patients. In this study, we evaluated the efficacy of intravitreal use of triamcinolone acetonide combined with laser photocoagulation for the treatment of diffuse diabetic macular edema and we compare it with either laser alone or intra-vitreal triancinolone. METHODS: In this study, performed between june 2005 and september 2006, we studied 30 well controlled diabetic patients with diffuse macular edema. These patients were randomly divided into the following treatment groups: (1) macular grid photocoagulation; (2) intravitreal injection of 4 mg of triamcinolone acetonide; (3) combination of the two previous therapies. Follow up was scheduled at predetermined intervals of one day, one week and monthly until completion of six months. The following parameters were analyzed: LogMAR best corrected visual acuity; central macular thickness and total macular volume measured by ocular coherence tomography; and intraocular pressure assessed by Goldman\'s tonometer. RESULTS: Grid photocoagulation did not significantly reduce the central macular thickness (p=0,0862) or the total macular volume (p=0,11). On the other side, this reduction was significant and statistically similar in the others two groups (p<0,001). All groups improved the mean visual acuity (p=0,003), however, the group that received the association treatment had a higher percentage of patients gaining 10 or more letters at the fourth and fifth month of follow up (p=0,026; p=0,034). A rise in 5 or more mmHg in intraocular pressure was observed in 12 patients; half of them was in the triamcinolone group and the other half was in the group that received combined therapies (p<0,001). These cases with elevated intraocular pressure were well controlled with timolol maleate 0,5% drops. CONCLUSION: The simultaneous use of photocoagulation and intravitreal triamcinolone provided a higher gain of visual lines than the isolated use of each treatment. The laser photocoagulation was the only therapy that did not significantly reduce the macular volume and the macular thickness, however, it was also the only one that did not present cases of ocular hypertension during follow up.

INTRODUÇÃO: O edema macular difuso é uma importante causa de baixa visual em portadores de diabetes mellitus. O tratamento clássico deste tipo de retinopatia consiste na fotocoagulação, entretanto, esta terapêutica é ineficaz em muitos casos. Neste trabalho, avaliou-se a eficácia do uso intravítreo da triancinolona acetonida associada à fotocoagulação com laser de argônio no tratamento do edema macular difuso diabético. Esta associação terapêutica foi comparada com o uso isolado de cada tratamento. MÉTODOS: Neste estudo, realizado entre junho de 2005 e setembro de 2006, foram estudados 30 pacientes diabéticos clinicamente controlados e portadores de edema macular difuso. Estes pacientes foram alocados de forma aleatória e proporcional em um dos seguintes grupos de tratamento: (1) fotocoagulação macular em grade com laser de argônio; (2) aplicação intravítrea de 4 mg de triancinolona acetonida; (3) associação dos itens anteriores. O seguimento foi realizado em intervalos pré-determinados de um dia, uma semana e mensalmente, até completar 6 meses. Foram analisados os parâmetros: acuidade visual corrigida LogMAR; espessura macular central e volume macular total medido pela tomografia de coerência óptica; e pressão intra-ocular aferida pelo tonômetro de Goldmann. RESULTADOS: A fotocoagulação com laser não reduziu de forma estatisticamente significativa a espessura macular central (p=0,0862) e o volume macular total (p=0,11). Esta redução foi significativa e estatisticamente semelhante nos outros dois grupos (p<0,001). Todos os grupos apresentaram melhora da acuidade visual (p=0,003), entretanto, o grupo que recebeu a associação do laser com a triancinolona intravítrea, obteve maior percentagem de pacientes com ganho de 10 ou mais letras de visão no quarto e quinto mês de seguimento (p=0,026; p=0,034). A pressão intra-ocular elevou-se em 5 mmHg ou mais em 12 pacientes, sendo seis no grupo submetido apenas a triancinolona e os outros seis no grupo que recebeu a associação de tratamento (p<0,001).Todos estes casos foram bem controlados com colírio de maleato de timolol 0,5%. CONCLUSÕES: O uso simultâneo da fotocoagulação com a triancinolona intravítrea proporcionou maior ganho de linhas de visão do que o uso isolado de cada tratamento. A fotocoagulação com laser foi a única terapia que não reduziu de forma significativa a espessura e o volume macular total e, também, foi a única que não apresentou casos de hipertensão ocular durante o seguimento. / INTRODUCTION: The diffuse macular edema is an important cause of visual impairment in diabetic subjects. Laser photocoagulation is the main treatment for this disorder, however, it is not effective in a large number of patients. In this study, we evaluated the efficacy of intravitreal use of triamcinolone acetonide combined with laser photocoagulation for the treatment of diffuse diabetic macular edema and we compare it with either laser alone or intra-vitreal triancinolone. METHODS: In this study, performed between june 2005 and september 2006, we studied 30 well controlled diabetic patients with diffuse macular edema. These patients were randomly divided into the following treatment groups: (1) macular grid photocoagulation; (2) intravitreal injection of 4 mg of triamcinolone acetonide; (3) combination of the two previous therapies. Follow up was scheduled at predetermined intervals of one day, one week and monthly until completion of six months. The following parameters were analyzed: LogMAR best corrected visual acuity; central macular thickness and total macular volume measured by ocular coherence tomography; and intraocular pressure assessed by Goldman\'s tonometer. RESULTS: Grid photocoagulation did not significantly reduce the central macular thickness (p=0,0862) or the total macular volume (p=0,11). On the other side, this reduction was significant and statistically similar in the others two groups (p<0,001). All groups improved the mean visual acuity (p=0,003), however, the group that received the association treatment had a higher percentage of patients gaining 10 or more letters at the fourth and fifth month of follow up (p=0,026; p=0,034). A rise in 5 or more mmHg in intraocular pressure was observed in 12 patients; half of them was in the triamcinolone group and the other half was in the group that received combined therapies (p<0,001). These cases with elevated intraocular pressure were well controlled with timolol maleate 0,5% drops. CONCLUSION: The simultaneous use of photocoagulation and intravitreal triamcinolone provided a higher gain of visual lines than the isolated use of each treatment. The laser photocoagulation was the only therapy that did not significantly reduce the macular volume and the macular thickness, however, it was also the only one that did not present cases of ocular hypertension during follow up.