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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Análise morfológica e funcional ocular de pacientes com doença de Vogt-Koyanagi-Harada no estágio tardio / Structural and functional ocular analysis of patients with late-stage Vogt-Koyanagi-Harada disease

Silva, Felipe Theodoro Bezerra Gaspar Carvalho da 22 August 2011 (has links)
OBJETIVO: Caracterizar morfologicamente e funcionalmente as alterações observadas no fundo de olho de pacientes com a doença de Vogt-Koyanagi- Harada (VKH) no estágio tardio. MÉTODOS: Estudo prospectivo, transversal, com inclusão de 36 pacientes com diagnóstico de doença de VKH no estágio tardio (definido como 6 meses ou mais após o início da doença) após obtenção do termo de consentimento livre e esclarecido. Fundo de olho (retinografia, RG) foi estratificado baseado em alterações difusas e focais assim como a função global da retina (eletroretinograma campo total, ERGct) segundo o método matemático de aglomeração (cluster). A concordância entre os dois métodos de estratificação foi estimada pelo teste kappa. Atividade clínica foi correlacionada com alterações indicativas de atividade de coróide pela angiografia com indocianina verde (AICV) (teste exato de Fisher). Alterações na integridade dos segmentos interno e externo de fotorreceptores (IS/OS) avaliada pela tomografia de coerência óptica espectral (OCT espectral) foram correlacionadas com a função macular (eletroretinograma multifocal, ERGmf) e acuidade visual (AV) (teste de Mann-Whitney). RESULTADOS: Houve concordância substancial entre os observadores em relação ao sistema analítico para estratificação fundoscópica proposto (kappa=0,78; intervalo de confiança 95%(IC95%)=0,63-0,93). Este sistema analítico também se correlacionou de maneira substancial com os achados do ERGct (kappa=0,68; IC 95% 0,52-1,07). Na avaliação com AICV, a proporção dos olhos com resultados compatíveis com atividade subclínica de coróide foi maior em pacientes com doença fundoscópica leve (12/13 olhos) se comparados exclusivamente com aqueles portadores de doença fundoscópica grave (11/19 olhos) (p=0,049). Os pacientes estratificados de acordo com as características fundoscópicas não diferiram de maneira substancial quanto aos aspectos clínicos. Atividade subclínica de coróide detectada pela AICV foi observada em 36 dos 51 olhos (72%). Atividade clínica (células na câmara anterior) foi observada em 21 dos 51 olhos (41%). Destes 76% (16/21) demonstravam sinais de atividade de coróide, ao passo que 5 de 21 olhos (24%) não os apresentavam. Dos pacientes com atividade clínica de doença e com AICV negativa, a maioria tinha doença grave (4/5 olhos) e nenhum tinha doença leve pela classificação fundoscópica. Quanto à função macular, as amplitudes e latências das ondas N1 e P1 diferiram dos controles (p<0,01). A junção IS/OS macular estava alterada em 17 de 42 olhos (40%) dos olhos. A AV foi diferente entre grupos estratificados de acordo com os resultados do ERGmf ( leve= 0,0 [20/20] e grave = 0,2 [20/32]; p<0,05) assim como entre os grupos estratificados pelo OCT espectral (IS/OS+ = 0,0 [20/20] e IS/OS-= 0,7 [20/100]; p<0,05). O grau de concordância entre estas estratégias foi baixo (K=0,17). CONCLUSÕES: O sistema analítico para achados fundoscópicos proposto teve alta reprodutibilidade e correlacionou-se com medidas objetivas de função retiniana (ERGct). A gravidade de doença estimada segundo a estratégia fundoscópica influencia a interpretação da AICV, sendo que pacientes com achados leves tendem a ter maior prevalência de atividade subclínica detectada pela AICV assim como pacientes graves apresentaram exame angiográfico negativo mesmo na vigência de atividade de segmento anterior. Os grupos estabelecidos com as estratégias funcional (ERGmf) e morfológica (OCT espectral) de análise macular diferiram significativamente em termos de acuidade visual, sendo que o ERGmf discerniu grupos com acuidades semelhantes. A concordância entre as duas técnicas de análise macular foi baixa devido à maior sensibilidade do ERGmf em detectar alterações. Estes dados sugerem que o dano funcional pode preceder e/ou ocorrer na ausência de alterações maculares detectáveis com o OCT espectral em pacientes no estágio tardio da doença de VKH / OBJECTIVES: To characterize the structural and functional derangements observed in eyes of patients with late-stage Vogt-Koyanagi-Harada (VKH) disease. METHODS: Cross sectional, prospective study including 36 patients diagnosed with late-stage VKH disease (defined as more than 6 months from disease`s onset) after obtainment of informed consent. Fundoscopy (retinography, RG) was stratified based on diffuse and focal findings as well as according to global retinal function (full-field electroretinogram, ffERG) applying cluster method of aggregation. The concordance between the two methods of stratification was estimated with the kappa test. Clinical disease activity was correlated with findings suggestive of subclinical choroidal activity on indocyanine green angiography (ICGA) (Fisher`s exact test). Disruption of photoreceptors inner and outer segments\' junction (IS/OS) evaluated using spectral optical coherence tomography (spectral OCT) was correlated with macular function (multifocal electroretinogram, mfERG) and best corrected visual acuity (BCVA)(Mann- Whitney test). RESULTS: Substantial interobserver concordance was detected with regard to the analytic system for fundus findings proposed (kappa=0.78; confidence interval 95%(CI95%); 0.63-0.93). This system also showed substantial correlation with ffERG findings (kappa=0.68; CI 95%; 0.52-1.07). Upon ICGA investigation, the proportion of eyes presenting signs of disease activity on ICGA was significantly greater among mild fundus cases (12/13) when compared exclusively with those presenting severe fundus disease (11/19) (p=0.049). The different severity categories based on fundoscopic evaluation did not differ in terms of clinical characteristics. Subclinical choroidal activity was observed in 36 of 51 eyes analyzed (72%). Clinical disease activity (cells in the anterior chamber) was observed in 21 of 51 eyes (41%). Most patients with clinical activity and negative ICGA examination (4/5) had severe disease and none had mild disease according to fundoscopic stratification. On macular evaluation, patients\' amplitudes and latencies of N1 and P1 waves differed from controls (p<0.01). Macular IS/OS junction was altered in 17 out of 42 eyes (40%). BCVA differed significantly between groups stratified according to both, mfERG (mild = 0.0 [20/20] and severe = 0.2 [20/32]; p<0.05) as well as spectral OCT (IS/OS+ = 0.0 [20/20] and IS/OS-= 0.7 [20/100]; p<0.05) assessment techniques. Concordance between these strategies of macular assessment was weak (K=0.17). CONCLUSIONS: The analytic system for fundus findings proposed herein demonstrated high reproducibility and substantial interobserver concordance with objective measures of retinal compromise (ffERG). The severity grading proposed influenced the interpretation of ICGA, as patients with mild disease had a greater proportion of positive findings while patients with severe disease presented negative ICGA in spite of anterior segment activity. Groups established according to both functional (mfERG) and morphological (spectral OCT) macular analysis strategies differed in terms of BCVA, although the mfERG distinguished groups with similar BCVA. The low concordance between the two strategies detected is attributable to the greater sensibility of the mfERG to detect alterations. These findings suggest that functional derangements may precede and/or occur in absence of alterations detectable with the spectral OCT in patients with late-stage VKH disease.
22

Análise integrada de parâmetros clínicos, estruturais e funcionais nas fases aguda e não aguda da doença de Vogt-Koyanagi-Harada: estudo longitudinal / Integrated analysis of clinical, structural and functional parameters in the acute and non-acute phases of Vogt-Koyanagi-Harada disease: a prospective study

Sakata, Viviane Mayumi 06 July 2015 (has links)
OBJETIVO: Descrever prospectivamente o curso da doença de Vogt-Koyanagi-Harada (DVKH) com integração de parâmetros de atividades clínicos, estruturais e funcionais. MÉTODOS: Foram incluídos pacientes com diagnóstico da DVKH na fase aguda (parte I) e não aguda (tempo de doença maior que 12 meses; parte II). Os pacientes na fase aguda receberam tratamento inicial padronizado com pulsoterapia de metilprednisolona seguido de corticoterapia oral em doses lentamente regressivas, pelo período de 15 meses. As avaliações consistiram em exame clínico, retinografia, angiografias com fluoresceína (AGF) e indocianina verde (AIV) e tomografia de coerência óptica (TCO). Foram realizadas nos seguintes momentos: parte I, no diagnóstico e meses 1, 2, 4, 6, 9 e 12; parte II, na inclusão e a cada três meses. Eletrorretinograma campo total (ERGct) e eletrorretinograma multifocal (ERGmf) foram realizados na parte I, no 1.o mês e a cada seis meses e, na parte II, na inclusão e com 12 meses. A leitura dos exames, na parte I, foi efetuada por duas leitoras, não mascaradas; na parte II, foi realizada por três leitores mascarados e treinados, sendo considerada a leitura concordante entre, pelo menos, dois examinadores. As angiografias e TCO foram realizadas no aparelho Spectralis® (HRA+OCT, Heidelberg Engineering). Tratamento adicional com corticoterapia em doses imunossupressoras ou intensificação da imunossupressão sistêmica foi indicado nos casos com recidivas clínicas, na presença de sinais de atividade à AGF ou duas pioras consecutivas >= 30% no ERGct. Os sinais de atividade detectados na AGF, AIV e TCO foram denominados sinais subclínicos. RESULTADOS: Na parte I, foram incluídos nove pacientes (7F/2M) com idade mediana de 33 anos e intervalo mediano entre início dos sintomas e tratamento de 13 dias. Na apresentação inicial, sinais clínicos característicos da doença (coroidite difusa com hiperemia do disco óptico, descolamento seroso de retina e uveíte anterior acompanhados de sinais extraoculares) melhoraram dentro dos primeiros 30 dias em todos os casos. Os principais sinais subclínicos variaram no tempo de melhora ou desaparecimento: espessura de coroide (EC) subfoveal diminuiu para o valor mediano de 347u m aos 30 dias; dark dots diminuíram ao longo do seguimento, porém ainda estavam presentes aos 12 meses. Piora da inflamação foi observada em 17 de 18 olhos no tempo mediano de sete meses quando a redução do corticoide oral atingiu a dose média de 0,3mg/kg/d. Os sinais subclínicos mais frequentemente observados foram dark dots, fuzzy vessels e aumento da EC. Em 10 destes 17 olhos a piora foi acompanhada de queda da função pelo ERG. Três padrões de evolução puderam ser caracterizados: sem recidivas clínicas ou subclínicas (padrão A, 1 olho), com recidivas subclínicas somente (padrão B, 11 olhos) e com recidivas clínicas (padrão C, 6 olhos). Identificou-se que a EC aos 30 dias após início do tratamento >= 506u m teve sensibilidade e especificidade > 80% na detecção dos casos com recidivas clínicas (padrão C). A função pelo ERGct e ERGmf permaneceu alterada em relação ao grupo controle com 24 meses, apesar da melhora progressiva observada desde o início do tratamento. Na análise longitudinal dos pacientes, a função entre 12 e 24 meses permaneceu estável no grupo de doentes que recebeu tratamento adicional (8 olhos), enquanto no grupo que não o recebeu (4 olhos) houve deterioração da função ( < 0,001). Na análise dos grupos segundo padrão de recidiva, observou-se que os olhos com padrão B sem tratamento adicional tinham piora funcional maior em relação àqueles com padrão C ou B tratados (p < 0,001). Na parte II, foram incluídos 20 pacientes (17F/3M), com idade mediana ao diagnóstico de 31 anos, intervalo mediano entre início de sintomas e tratamento de 19 dias e tempo mediano de doença à inclusão de 55 meses. Na avaliação da concordância interobservador na leitura dos sinais subclínicos, EC teve concordância substancial (kappa=0,8), enquanto sinais angiográficos tiveram concordância sutil (kappa < 0,2). O curso da doença em 85% dos pacientes foi com recidiva clínica (padrão C, 11 casos) ou recidiva subclínica (padrão B, 6 casos). Nas 11 avaliações com detecção de células na câmara anterior (CA), sinais subclínicos de inflamação de segmento posterior foram concomitantemente observados em 64% dos olhos. Esta mesma concomitância de sinais subclínicos de inflamação de segmento posterior na presença de células na CA foi observada na parte I do estudo. Nos pacientes com padrão B, a variação da EC foi o principal sinal subclínico observado. A função pelo ERG foi realizada sequencialmente em 13 casos. Olhos com padrão C (7 pacientes), com grande comprometimento funcional desde a inclusão, evoluíram com piora mais acentuada do que aqueles com padrão B (5 pacientes). Ao se individualizar os olhos com padrão B, observou-se que esse diferencial (padrão B melhor que C) devia-se ao grupo padrão B com tratamento (p < 0,001). CONCLUSÕES: Neste estudo prospectivo de pacientes com DVKH em seguimento mínimo de 12 meses, desde as fases aguda e não aguda, três padrões de evolução foram observados, sendo que 94% (parte I) e 85% (parte II) dos pacientes apresentaram recidiva/piora clínica (padrão C) e/ou subclínica (padrão B). Na parte I do estudo, a piora da inflamação foi detectada aos sete meses de evolução durante dose regressiva do corticoide equivalente a 0,3mg/kg/d, apesar do tratamento inicial com corticoides em altas doses lentamente regressivo. A EC aferida 30 dias após o início do tratamento acima de 506 ?m mostrou-se um fator com sensibilidade e especificidade acima de 80% na identificação dos casos que evoluíram com recidivas clínicas. Dentre os sinais para detecção de inflamação subclínica, as alterações na EC são confiáveis, enquanto que sinais angiográficos devem ser interpretados com cautela. Exames sequenciais tornam a leitura mais confiável. A presença de células na CA comportou-se como a \"ponta do iceberg\" de uma inflamação mais difusa. O estudo eletrorretinográfico demonstrou resultado subnormal mesmo após 24 meses de seguimento na parte I; tratamento adicional pode evitar piora funcional nos pacientes com sinais subclínicos de inflamação. A pior função da retina em pacientes com inflamação clínica (padrão C) da parte II e dos pacientes com inflamação subclínica (padrão B) de ambas as partes do estudo sugerem que o tratamento ideal das recidivas inflamatórias ainda deve ser alvo de futuros estudos / OBJECTIVES: To describe the course of Vogt-Koyanagi-Harada disease (VKHD) prospectively, integrating clinical, structural and functional parameters. METHODS: Patients with VKHD in the acute (part I) and non-acute (more than 12 months from diagnosis) phases (part II) were included. Patients in the acute phase received a standard treatment with methylprednisolone pulsetherapy followed by high-dose oral corticosteroids with slow tapering during 15 months. Evaluations included clinical exams, fluorescein (FA) and indocyanine green (ICGA) angiographies and optical coherence tomography (OCT). In part I, they were performed at inclusion, then after 1,2,4,6,9,and 12 months; in part II, they were performed at inclusion then every 3 months for up to 12 months. Functional evaluation using electroretinography (ERG) was performed at inclusion and every 6 months in part I and at inclusion and at 12 months in part II. Two non-blinded readers analyzed the imaging exams in part I. In part II, three trained and blinded-readers performed the imaging exams analysis. For study`s purpose, at least two concordant readings were considered. Imaging exams utilized the Spectralis® (HRA+OCT, Heidelberg engineering). Inflammatory signs detected on FA, ICGA and OCT were denominated as subclinical signs. Additional treatment with high doses of corticosteroids or more intensive systemic immunosuppression was indicated in cases with clinical signs of inflammation, with subclinical signs on FA or with two consecutive worsening > 30% on ERG. RESULTS: Nine patients (7F/2M) were included in part I; median age was 33 years old and median time elapsed from onset of symptoms to treatment was 13 days. At disease presentation, classic signs (choroiditis, anterior uveitis, serous retinal detachment, optic disc hyperemia and extraocular manifestations) were observed; they improved in 30 days after treatment. Subclinical signs improved in variable periods of time: subfoveal choroidal thickness (CT) decreased to a median value of 347 ?m, 30 days after the beginning of treatment, dark dots diminished during the follow-up but they were still observed at 12 months. Relapse (worsening of inflammation) was noticed in 17 of 18 eyes at a median follow up time of seven months, when tapering schedule corticosteroid dosage reached the mean dose of 0.3mg/kg/d of prednisone. Dark dots, fuzzy vessels and choroid thickening were the most frequent subclinical signs. Relapses in 10 of 17 eyes were concomitant with worsening on ERG. Three patterns of evolution could be delineated: no signs of inflammation (pattern A, 1 eye), only subclinical signs of inflammation (pattern B, 11 eyes) and clinical signs of inflammation (pattern C, 6 eyes). CT>=506 ?m 30 days after the beginning of treatment was more than 80% sensitive and specific to detect more severe cases (pattern C). ERG parameters at 24 months were subnormal as compared to the control group, despite improvement during follow-up. Further long-term results after 24 month demonstrated stabilization of ERG parameters in patients that had received additional treatment, whereas there was worsening in those patients who had not received additional treatment (p<0.001). Moreover, pattern B patients without additional treatment had a further decrease on ERG values compared to results observed in pattern C or B patients with additional treatment (p<0.001). In Part II, 20 patients (17F/3M) were included; median age at diagnosis was 31 years old, median lag time from onset of symptoms and treatment was 19 days and median time after diagnosis was 55 months. The interobserver agreement for CT reading was substantial (kappa 0.8), whereas for angiographic signs was slight (kappa < 0.2). Recurrences, clinically (pattern C, 11 cases) or subclinically (pattern B, 6 cases) detected, were observed in 85% of cases. Concomitant inflammation of posterior segment detected by subclinical signs was present in 64% of cases with cells in anterior chamber. Simultaneous signs of subclinical inflammation of posterior segment and anterior uveitis were also observed in part I. CT change was the main subclinical sign observed in pattern B patients. ERG evaluation was performed in 13 cases. Pattern C cases (7 patients) presented worse results than pattern B cases (5 patients). Further analysis depicted that pattern B patients who had an additional treatment had better results than pattern B non-treated and pattern C (p<0.001). CONCLUSION: Three patterns of evolution were observed in VKHD patients during this prospective study, 94% (part I) and 85% (part II) presented recurrence/worsening with clinical (pattern C) or subclinical (Pattern B) signs of inflammation. In part I, worsening was observed at seven months after treatment start when reaching mean dose of 0.3mg/Kg/d of prednisone even after initial high-dose of corticosteroids followed by slow tapering. At day 30 after treatment, CT >= 506 ?m had a greater than 80% sensitivity and specificity to detect cases with pattern C evolution. Considering subclinical signs, CT increase reliably detected recurrence, whereas angiographic signs required cautious interpretation. Sequential analysis was more conclusive than an isolated exam. Anterior chamber cells seemed to be the \"tip of the iceberg\" of a more diffuse inflammation. ERG analysis was subnormal even after 24 months of follow up since disease onset; additional treatment could prevent functional worsening in patients with subclinical signs of inflammation. Worse retinal function in patients with clinical recurrences (pattern C) in part II and subclinical recurrences (pattern B) in parts I and II suggest that ideal treatment of recurrences should be further pursued
23

Análise integrada de parâmetros clínicos, estruturais e funcionais nas fases aguda e não aguda da doença de Vogt-Koyanagi-Harada: estudo longitudinal / Integrated analysis of clinical, structural and functional parameters in the acute and non-acute phases of Vogt-Koyanagi-Harada disease: a prospective study

Viviane Mayumi Sakata 06 July 2015 (has links)
OBJETIVO: Descrever prospectivamente o curso da doença de Vogt-Koyanagi-Harada (DVKH) com integração de parâmetros de atividades clínicos, estruturais e funcionais. MÉTODOS: Foram incluídos pacientes com diagnóstico da DVKH na fase aguda (parte I) e não aguda (tempo de doença maior que 12 meses; parte II). Os pacientes na fase aguda receberam tratamento inicial padronizado com pulsoterapia de metilprednisolona seguido de corticoterapia oral em doses lentamente regressivas, pelo período de 15 meses. As avaliações consistiram em exame clínico, retinografia, angiografias com fluoresceína (AGF) e indocianina verde (AIV) e tomografia de coerência óptica (TCO). Foram realizadas nos seguintes momentos: parte I, no diagnóstico e meses 1, 2, 4, 6, 9 e 12; parte II, na inclusão e a cada três meses. Eletrorretinograma campo total (ERGct) e eletrorretinograma multifocal (ERGmf) foram realizados na parte I, no 1.o mês e a cada seis meses e, na parte II, na inclusão e com 12 meses. A leitura dos exames, na parte I, foi efetuada por duas leitoras, não mascaradas; na parte II, foi realizada por três leitores mascarados e treinados, sendo considerada a leitura concordante entre, pelo menos, dois examinadores. As angiografias e TCO foram realizadas no aparelho Spectralis® (HRA+OCT, Heidelberg Engineering). Tratamento adicional com corticoterapia em doses imunossupressoras ou intensificação da imunossupressão sistêmica foi indicado nos casos com recidivas clínicas, na presença de sinais de atividade à AGF ou duas pioras consecutivas >= 30% no ERGct. Os sinais de atividade detectados na AGF, AIV e TCO foram denominados sinais subclínicos. RESULTADOS: Na parte I, foram incluídos nove pacientes (7F/2M) com idade mediana de 33 anos e intervalo mediano entre início dos sintomas e tratamento de 13 dias. Na apresentação inicial, sinais clínicos característicos da doença (coroidite difusa com hiperemia do disco óptico, descolamento seroso de retina e uveíte anterior acompanhados de sinais extraoculares) melhoraram dentro dos primeiros 30 dias em todos os casos. Os principais sinais subclínicos variaram no tempo de melhora ou desaparecimento: espessura de coroide (EC) subfoveal diminuiu para o valor mediano de 347u m aos 30 dias; dark dots diminuíram ao longo do seguimento, porém ainda estavam presentes aos 12 meses. Piora da inflamação foi observada em 17 de 18 olhos no tempo mediano de sete meses quando a redução do corticoide oral atingiu a dose média de 0,3mg/kg/d. Os sinais subclínicos mais frequentemente observados foram dark dots, fuzzy vessels e aumento da EC. Em 10 destes 17 olhos a piora foi acompanhada de queda da função pelo ERG. Três padrões de evolução puderam ser caracterizados: sem recidivas clínicas ou subclínicas (padrão A, 1 olho), com recidivas subclínicas somente (padrão B, 11 olhos) e com recidivas clínicas (padrão C, 6 olhos). Identificou-se que a EC aos 30 dias após início do tratamento >= 506u m teve sensibilidade e especificidade > 80% na detecção dos casos com recidivas clínicas (padrão C). A função pelo ERGct e ERGmf permaneceu alterada em relação ao grupo controle com 24 meses, apesar da melhora progressiva observada desde o início do tratamento. Na análise longitudinal dos pacientes, a função entre 12 e 24 meses permaneceu estável no grupo de doentes que recebeu tratamento adicional (8 olhos), enquanto no grupo que não o recebeu (4 olhos) houve deterioração da função ( < 0,001). Na análise dos grupos segundo padrão de recidiva, observou-se que os olhos com padrão B sem tratamento adicional tinham piora funcional maior em relação àqueles com padrão C ou B tratados (p < 0,001). Na parte II, foram incluídos 20 pacientes (17F/3M), com idade mediana ao diagnóstico de 31 anos, intervalo mediano entre início de sintomas e tratamento de 19 dias e tempo mediano de doença à inclusão de 55 meses. Na avaliação da concordância interobservador na leitura dos sinais subclínicos, EC teve concordância substancial (kappa=0,8), enquanto sinais angiográficos tiveram concordância sutil (kappa < 0,2). O curso da doença em 85% dos pacientes foi com recidiva clínica (padrão C, 11 casos) ou recidiva subclínica (padrão B, 6 casos). Nas 11 avaliações com detecção de células na câmara anterior (CA), sinais subclínicos de inflamação de segmento posterior foram concomitantemente observados em 64% dos olhos. Esta mesma concomitância de sinais subclínicos de inflamação de segmento posterior na presença de células na CA foi observada na parte I do estudo. Nos pacientes com padrão B, a variação da EC foi o principal sinal subclínico observado. A função pelo ERG foi realizada sequencialmente em 13 casos. Olhos com padrão C (7 pacientes), com grande comprometimento funcional desde a inclusão, evoluíram com piora mais acentuada do que aqueles com padrão B (5 pacientes). Ao se individualizar os olhos com padrão B, observou-se que esse diferencial (padrão B melhor que C) devia-se ao grupo padrão B com tratamento (p < 0,001). CONCLUSÕES: Neste estudo prospectivo de pacientes com DVKH em seguimento mínimo de 12 meses, desde as fases aguda e não aguda, três padrões de evolução foram observados, sendo que 94% (parte I) e 85% (parte II) dos pacientes apresentaram recidiva/piora clínica (padrão C) e/ou subclínica (padrão B). Na parte I do estudo, a piora da inflamação foi detectada aos sete meses de evolução durante dose regressiva do corticoide equivalente a 0,3mg/kg/d, apesar do tratamento inicial com corticoides em altas doses lentamente regressivo. A EC aferida 30 dias após o início do tratamento acima de 506 ?m mostrou-se um fator com sensibilidade e especificidade acima de 80% na identificação dos casos que evoluíram com recidivas clínicas. Dentre os sinais para detecção de inflamação subclínica, as alterações na EC são confiáveis, enquanto que sinais angiográficos devem ser interpretados com cautela. Exames sequenciais tornam a leitura mais confiável. A presença de células na CA comportou-se como a \"ponta do iceberg\" de uma inflamação mais difusa. O estudo eletrorretinográfico demonstrou resultado subnormal mesmo após 24 meses de seguimento na parte I; tratamento adicional pode evitar piora funcional nos pacientes com sinais subclínicos de inflamação. A pior função da retina em pacientes com inflamação clínica (padrão C) da parte II e dos pacientes com inflamação subclínica (padrão B) de ambas as partes do estudo sugerem que o tratamento ideal das recidivas inflamatórias ainda deve ser alvo de futuros estudos / OBJECTIVES: To describe the course of Vogt-Koyanagi-Harada disease (VKHD) prospectively, integrating clinical, structural and functional parameters. METHODS: Patients with VKHD in the acute (part I) and non-acute (more than 12 months from diagnosis) phases (part II) were included. Patients in the acute phase received a standard treatment with methylprednisolone pulsetherapy followed by high-dose oral corticosteroids with slow tapering during 15 months. Evaluations included clinical exams, fluorescein (FA) and indocyanine green (ICGA) angiographies and optical coherence tomography (OCT). In part I, they were performed at inclusion, then after 1,2,4,6,9,and 12 months; in part II, they were performed at inclusion then every 3 months for up to 12 months. Functional evaluation using electroretinography (ERG) was performed at inclusion and every 6 months in part I and at inclusion and at 12 months in part II. Two non-blinded readers analyzed the imaging exams in part I. In part II, three trained and blinded-readers performed the imaging exams analysis. For study`s purpose, at least two concordant readings were considered. Imaging exams utilized the Spectralis® (HRA+OCT, Heidelberg engineering). Inflammatory signs detected on FA, ICGA and OCT were denominated as subclinical signs. Additional treatment with high doses of corticosteroids or more intensive systemic immunosuppression was indicated in cases with clinical signs of inflammation, with subclinical signs on FA or with two consecutive worsening > 30% on ERG. RESULTS: Nine patients (7F/2M) were included in part I; median age was 33 years old and median time elapsed from onset of symptoms to treatment was 13 days. At disease presentation, classic signs (choroiditis, anterior uveitis, serous retinal detachment, optic disc hyperemia and extraocular manifestations) were observed; they improved in 30 days after treatment. Subclinical signs improved in variable periods of time: subfoveal choroidal thickness (CT) decreased to a median value of 347 ?m, 30 days after the beginning of treatment, dark dots diminished during the follow-up but they were still observed at 12 months. Relapse (worsening of inflammation) was noticed in 17 of 18 eyes at a median follow up time of seven months, when tapering schedule corticosteroid dosage reached the mean dose of 0.3mg/kg/d of prednisone. Dark dots, fuzzy vessels and choroid thickening were the most frequent subclinical signs. Relapses in 10 of 17 eyes were concomitant with worsening on ERG. Three patterns of evolution could be delineated: no signs of inflammation (pattern A, 1 eye), only subclinical signs of inflammation (pattern B, 11 eyes) and clinical signs of inflammation (pattern C, 6 eyes). CT>=506 ?m 30 days after the beginning of treatment was more than 80% sensitive and specific to detect more severe cases (pattern C). ERG parameters at 24 months were subnormal as compared to the control group, despite improvement during follow-up. Further long-term results after 24 month demonstrated stabilization of ERG parameters in patients that had received additional treatment, whereas there was worsening in those patients who had not received additional treatment (p<0.001). Moreover, pattern B patients without additional treatment had a further decrease on ERG values compared to results observed in pattern C or B patients with additional treatment (p<0.001). In Part II, 20 patients (17F/3M) were included; median age at diagnosis was 31 years old, median lag time from onset of symptoms and treatment was 19 days and median time after diagnosis was 55 months. The interobserver agreement for CT reading was substantial (kappa 0.8), whereas for angiographic signs was slight (kappa < 0.2). Recurrences, clinically (pattern C, 11 cases) or subclinically (pattern B, 6 cases) detected, were observed in 85% of cases. Concomitant inflammation of posterior segment detected by subclinical signs was present in 64% of cases with cells in anterior chamber. Simultaneous signs of subclinical inflammation of posterior segment and anterior uveitis were also observed in part I. CT change was the main subclinical sign observed in pattern B patients. ERG evaluation was performed in 13 cases. Pattern C cases (7 patients) presented worse results than pattern B cases (5 patients). Further analysis depicted that pattern B patients who had an additional treatment had better results than pattern B non-treated and pattern C (p<0.001). CONCLUSION: Three patterns of evolution were observed in VKHD patients during this prospective study, 94% (part I) and 85% (part II) presented recurrence/worsening with clinical (pattern C) or subclinical (Pattern B) signs of inflammation. In part I, worsening was observed at seven months after treatment start when reaching mean dose of 0.3mg/Kg/d of prednisone even after initial high-dose of corticosteroids followed by slow tapering. At day 30 after treatment, CT >= 506 ?m had a greater than 80% sensitivity and specificity to detect cases with pattern C evolution. Considering subclinical signs, CT increase reliably detected recurrence, whereas angiographic signs required cautious interpretation. Sequential analysis was more conclusive than an isolated exam. Anterior chamber cells seemed to be the \"tip of the iceberg\" of a more diffuse inflammation. ERG analysis was subnormal even after 24 months of follow up since disease onset; additional treatment could prevent functional worsening in patients with subclinical signs of inflammation. Worse retinal function in patients with clinical recurrences (pattern C) in part II and subclinical recurrences (pattern B) in parts I and II suggest that ideal treatment of recurrences should be further pursued
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Análise morfológica e funcional ocular de pacientes com doença de Vogt-Koyanagi-Harada no estágio tardio / Structural and functional ocular analysis of patients with late-stage Vogt-Koyanagi-Harada disease

Felipe Theodoro Bezerra Gaspar Carvalho da Silva 22 August 2011 (has links)
OBJETIVO: Caracterizar morfologicamente e funcionalmente as alterações observadas no fundo de olho de pacientes com a doença de Vogt-Koyanagi- Harada (VKH) no estágio tardio. MÉTODOS: Estudo prospectivo, transversal, com inclusão de 36 pacientes com diagnóstico de doença de VKH no estágio tardio (definido como 6 meses ou mais após o início da doença) após obtenção do termo de consentimento livre e esclarecido. Fundo de olho (retinografia, RG) foi estratificado baseado em alterações difusas e focais assim como a função global da retina (eletroretinograma campo total, ERGct) segundo o método matemático de aglomeração (cluster). A concordância entre os dois métodos de estratificação foi estimada pelo teste kappa. Atividade clínica foi correlacionada com alterações indicativas de atividade de coróide pela angiografia com indocianina verde (AICV) (teste exato de Fisher). Alterações na integridade dos segmentos interno e externo de fotorreceptores (IS/OS) avaliada pela tomografia de coerência óptica espectral (OCT espectral) foram correlacionadas com a função macular (eletroretinograma multifocal, ERGmf) e acuidade visual (AV) (teste de Mann-Whitney). RESULTADOS: Houve concordância substancial entre os observadores em relação ao sistema analítico para estratificação fundoscópica proposto (kappa=0,78; intervalo de confiança 95%(IC95%)=0,63-0,93). Este sistema analítico também se correlacionou de maneira substancial com os achados do ERGct (kappa=0,68; IC 95% 0,52-1,07). Na avaliação com AICV, a proporção dos olhos com resultados compatíveis com atividade subclínica de coróide foi maior em pacientes com doença fundoscópica leve (12/13 olhos) se comparados exclusivamente com aqueles portadores de doença fundoscópica grave (11/19 olhos) (p=0,049). Os pacientes estratificados de acordo com as características fundoscópicas não diferiram de maneira substancial quanto aos aspectos clínicos. Atividade subclínica de coróide detectada pela AICV foi observada em 36 dos 51 olhos (72%). Atividade clínica (células na câmara anterior) foi observada em 21 dos 51 olhos (41%). Destes 76% (16/21) demonstravam sinais de atividade de coróide, ao passo que 5 de 21 olhos (24%) não os apresentavam. Dos pacientes com atividade clínica de doença e com AICV negativa, a maioria tinha doença grave (4/5 olhos) e nenhum tinha doença leve pela classificação fundoscópica. Quanto à função macular, as amplitudes e latências das ondas N1 e P1 diferiram dos controles (p<0,01). A junção IS/OS macular estava alterada em 17 de 42 olhos (40%) dos olhos. A AV foi diferente entre grupos estratificados de acordo com os resultados do ERGmf ( leve= 0,0 [20/20] e grave = 0,2 [20/32]; p<0,05) assim como entre os grupos estratificados pelo OCT espectral (IS/OS+ = 0,0 [20/20] e IS/OS-= 0,7 [20/100]; p<0,05). O grau de concordância entre estas estratégias foi baixo (K=0,17). CONCLUSÕES: O sistema analítico para achados fundoscópicos proposto teve alta reprodutibilidade e correlacionou-se com medidas objetivas de função retiniana (ERGct). A gravidade de doença estimada segundo a estratégia fundoscópica influencia a interpretação da AICV, sendo que pacientes com achados leves tendem a ter maior prevalência de atividade subclínica detectada pela AICV assim como pacientes graves apresentaram exame angiográfico negativo mesmo na vigência de atividade de segmento anterior. Os grupos estabelecidos com as estratégias funcional (ERGmf) e morfológica (OCT espectral) de análise macular diferiram significativamente em termos de acuidade visual, sendo que o ERGmf discerniu grupos com acuidades semelhantes. A concordância entre as duas técnicas de análise macular foi baixa devido à maior sensibilidade do ERGmf em detectar alterações. Estes dados sugerem que o dano funcional pode preceder e/ou ocorrer na ausência de alterações maculares detectáveis com o OCT espectral em pacientes no estágio tardio da doença de VKH / OBJECTIVES: To characterize the structural and functional derangements observed in eyes of patients with late-stage Vogt-Koyanagi-Harada (VKH) disease. METHODS: Cross sectional, prospective study including 36 patients diagnosed with late-stage VKH disease (defined as more than 6 months from disease`s onset) after obtainment of informed consent. Fundoscopy (retinography, RG) was stratified based on diffuse and focal findings as well as according to global retinal function (full-field electroretinogram, ffERG) applying cluster method of aggregation. The concordance between the two methods of stratification was estimated with the kappa test. Clinical disease activity was correlated with findings suggestive of subclinical choroidal activity on indocyanine green angiography (ICGA) (Fisher`s exact test). Disruption of photoreceptors inner and outer segments\' junction (IS/OS) evaluated using spectral optical coherence tomography (spectral OCT) was correlated with macular function (multifocal electroretinogram, mfERG) and best corrected visual acuity (BCVA)(Mann- Whitney test). RESULTS: Substantial interobserver concordance was detected with regard to the analytic system for fundus findings proposed (kappa=0.78; confidence interval 95%(CI95%); 0.63-0.93). This system also showed substantial correlation with ffERG findings (kappa=0.68; CI 95%; 0.52-1.07). Upon ICGA investigation, the proportion of eyes presenting signs of disease activity on ICGA was significantly greater among mild fundus cases (12/13) when compared exclusively with those presenting severe fundus disease (11/19) (p=0.049). The different severity categories based on fundoscopic evaluation did not differ in terms of clinical characteristics. Subclinical choroidal activity was observed in 36 of 51 eyes analyzed (72%). Clinical disease activity (cells in the anterior chamber) was observed in 21 of 51 eyes (41%). Most patients with clinical activity and negative ICGA examination (4/5) had severe disease and none had mild disease according to fundoscopic stratification. On macular evaluation, patients\' amplitudes and latencies of N1 and P1 waves differed from controls (p<0.01). Macular IS/OS junction was altered in 17 out of 42 eyes (40%). BCVA differed significantly between groups stratified according to both, mfERG (mild = 0.0 [20/20] and severe = 0.2 [20/32]; p<0.05) as well as spectral OCT (IS/OS+ = 0.0 [20/20] and IS/OS-= 0.7 [20/100]; p<0.05) assessment techniques. Concordance between these strategies of macular assessment was weak (K=0.17). CONCLUSIONS: The analytic system for fundus findings proposed herein demonstrated high reproducibility and substantial interobserver concordance with objective measures of retinal compromise (ffERG). The severity grading proposed influenced the interpretation of ICGA, as patients with mild disease had a greater proportion of positive findings while patients with severe disease presented negative ICGA in spite of anterior segment activity. Groups established according to both functional (mfERG) and morphological (spectral OCT) macular analysis strategies differed in terms of BCVA, although the mfERG distinguished groups with similar BCVA. The low concordance between the two strategies detected is attributable to the greater sensibility of the mfERG to detect alterations. These findings suggest that functional derangements may precede and/or occur in absence of alterations detectable with the spectral OCT in patients with late-stage VKH disease.
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Novel Intraoperative Imaging of Gastric Tube Perfusion during Oncologic Esophagectomy—A Pilot Study Comparing Hyperspectral Imaging (HSI) and Fluorescence Imaging (FI) with Indocyanine Green (ICG)

Hennig, Sebastian, Jansen-Winkeln, Boris, Köhler, Hannes, Knospe, Luise, Chalopin, Claire, Maktabi, Marianne, Pfahl, Annekatrin, Hoffmann, Jana, Kwast, Stefan, Gockel, Ines, Moulla, Yusef 02 May 2023 (has links)
Background: Novel intraoperative imaging techniques, namely, hyperspectral (HSI) and fluorescence imaging (FI), are promising with respect to reducing severe postoperative complications, thus increasing patient safety. Both tools have already been used to evaluate perfusion of the gastric conduit after esophagectomy and before anastomosis. To our knowledge, this is the first study evaluating both modalities simultaneously during esophagectomy. Methods: In our pilot study, 13 patients, who underwent Ivor Lewis esophagectomy and gastric conduit reconstruction, were analyzed prospectively. HSI and FI were recorded before establishing the anastomosis in order to determine its optimum position. Results: No anastomotic leak occurred during this pilot study. In five patients, the imaging methods resulted in a more peripheral adaptation of the anastomosis. There were no significant differences between the two imaging tools, and no adverse events due to the imaging methods or indocyanine green (ICG) injection occurred. Conclusions: Simultaneous intraoperative application of both modalities was feasible and not time consuming. They are complementary with regard to the ideal anastomotic position and may contribute to better surgical outcomes. The impact of their simultaneous application will be proven in consecutive prospective trials with a large patient cohort.
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New Intraoperative Imaging Tools and Image-Guided Surgery in Gastric Cancer Surgery

Knospe, Luise, Gockel, Ines, Jansen-Winkeln, Boris, Thieme, René, Niebisch, Stefan, Moulla, Yusef, Stelzner, Sigmar, Lyros, Orestis, Diana, Michele, Marescaux, Jacques, Chalopin, Claire, Köhler, Hannes, Pfahl, Annekatrin, Maktabi, Marianne, Park, Ji-Hyeon, Yang, Han-Kwang 02 June 2023 (has links)
Innovations and new advancements in intraoperative real-time imaging have gained significant importance in the field of gastric cancer surgery in the recent past. Currently, the most promising procedures include indocyanine green fluorescence imaging (ICG-FI) and hyperspectral imaging or multispectral imaging (HSI, MSI). ICG-FI is utilized in a broad range of clinical applications, e.g., assessment of perfusion or lymphatic drainage, and additional implementations are currently investigated. HSI is still in the experimental phase and its value and clinical relevance require further evaluation, but initial studies have shown a successful application in perfusion assessment, and prospects concerning non-invasive tissue and tumor classification are promising. The application of machine learning and artificial intelligence technologies might enable an automatic evaluation of the acquired image data in the future. Both methods facilitate the accurate visualization of tissue characteristics that are initially indistinguishable for the human eye. By aiding surgeons in optimizing the surgical procedure, image-guided surgery can contribute to the oncologic safety and reduction of complications in gastric cancer surgery and recent advances hold promise for the application of HSI in intraoperative tissue diagnostics.
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Ultrastructure of the Membrana Limitans Interna after Dye-Assisted Membrane Peeling

Brockmann, Tobias, Steger, Claudia, Westermann, Martin, Nietzsche, Sandor, Königsdörffer, Ekkehart, Strobel, Jürgen, Dawczynski, Jens 27 July 2022 (has links)
The purpose of this study was to investigate the ultrastructure of the membrana limitans interna (internal limiting membrane, ILM) and to evaluate alterations to the retinal cell layers after membrane peeling with vital dyes. Twenty-five patients (25 eyes) who underwent macular hole surgery were included, whereby 12 indocyanine green (ICG)- and 13 brilliant blue G (BBG)-stained ILM were analyzed using light, transmission electron and scanning electron microscopy. Retinal cell fragments on the ILM were identified in both groups using immunohistochemistry. Comparing ICG- and BBG-stained membranes, larger cellular fragments were observed at a higher frequency in the BBG group. Thereby, the findings indicate that ICG permits an enhanced separation of the ILM from the underlying retina with less mechanical destruction. A possible explanation might be seen in the known photosensitivity of ICG, which induces a stiffening and shrinkage of the ILM but also generates retinal toxic metabolites
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Le rôle de l’angiographie au vert d’indocyanine en chirurgie pédiatrique

Le-Nguyen, Annie 04 1900 (has links)
L’angiographie par fluorescence au vert d’indocyanine (ICG-FA) est une technologie d’imagerie non-invasive ayant été validée pour évaluer la perfusion tissulaire, pour délimiter l’anatomie des voies biliaires extra-hépatiques et pour localiser les ganglions et les vaisseaux lymphatiques. Depuis les années 2000, son utilisation connaît une expansion dans diverses spécialités chirurgicales incluant la chirurgie pédiatrique. Ce mémoire explore les indications actuelles de l’angiographie par fluorescence au vert d’indocyanine en pédiatrie et son introduction lors de résections intestinales pédiatriques à l’aide d’un essai clinique prospectif de faisabilité. Alors que l’utilisation de l’ICG-FA est bien définie en chirurgie adulte, cette technologie demeure peu utilisée en pédiatrie. Une revue systématique avec synthèse narrative portant sur l’utilisation de la technologie en contexte périopératoire chez la population pédiatrique a été menée. La majorité des articles étaient des études de cas et des séries de cas (n=36 ; 56%). Aucun effet indésirable relié au vert d’indocyanine n’a été rapporté. Le risque de biais de sélection et d’information était élevé. Les résultats de la revue systématique indiquent que bien que les indications demeurent limitées en pédiatrie, un intérêt important pour la technologie est noté à travers l’augmentation du nombre de publications sur le sujet. L’ICG-FA est un outil fréquemment utilisé en chirurgie colorectale adulte pour évaluer la vascularisation intestinale. Un essai clinique prospectif de phase II a été mené afin d’établir la faisabilité et l’impact de l’utilisation de l’ICG-FA lors de chirurgies pédiatriques d’urgence et électives nécessitant une résection intestinale. Les résultats de l’étude prouvent que l’introduction de la technologie est faisable, sécuritaire et simple. Par ailleurs, 95% des membres de l’équipe chirurgicale considèrent la technologie sécuritaire. / Indocyanine green fluorescence angiography (ICG-FA) is a validated non-invasive imaging technology used to evaluate tissue perfusion, delineate biliary anatomy, and localize lymph nodes and lymphatic vessels. Since the 2000s, its use has grown in various surgical subspecialties including pediatric surgery. This thesis explores the current ICG-FA indications in pediatric surgical subspecialties and its introduction in pediatric bowel resections by the mean of a prospective feasibility clinical trial. While ICG-FA is well established in adult surgery, the technology remains sparsely used in pediatric surgery. A systematic review with narrative synthesis on the perioperative ICG-FA use in the pediatric population was conducted. Most articles were case reports and case series (n=36; 56%). No adverse event related to ICG occurred. Risk of selection and information biases was high. The results show that pediatric applications of ICG remain currently limited, but significant interest in the technology is seen with the rising number of publications on the subject. ICG-FA is a frequently used tool in adult colorectal surgery to determine intestinal perfusion. A prospective Phase II clinical trial was conducted to establish the feasibility and impact of ICG-FA use during emergency and elective pediatric surgeries requiring bowel resection. The study results indicate that the introduction of the technology is feasible, safe, and simple. They show that 95% of the surgical team agreed that ICG-FA was safe.
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La chirurgie digestive oncologique aidée par la fluorescence / Oncological digestive surgery using fluorescence

Barabino, Gabriele 22 October 2015 (has links)
Dans notre travail de thèse, nous nous sommes attachés à répondre à cette question : peut-t-on améliorer la résécabilité tumorale dans le métastases hépatiques et péritonéales du cancer colorectal? Pour cela nous nous sommes appuyés sur deux éléments : la fluorescence du vert d’indocyanine et sa détection par la caméra NIR. Dans un premier temps, après une mise au point en laboratoire, nous avons appliqué cette technique aux résections hépatiques. Nous avons montré que cette technique a un double intérêt : la détection des lésions tumorales et l’amélioration de la marge de résection oncologique. La question encore ouverte est le pourcentage de cellules cancéreuses ou précancéreuses présentent dans cette couronne fluorescente. Dans un deuxième temps nous avons appliqué cette technique dans la carcinose péritonéale. Il s’agit d’une première étude de faisabilité car nous n’avons retrouvé aucune publication sur ce sujet. Nous avons pu montrer des similitudes avec l’étude sur le foie. La fluorescence de l’ICG permet de détecter des tumeurs du péritoine difficilement visibles à l’œil nu grâce à l’intensité et à la qualité de la fluorescence même. Les perspectives sont centrées sur deux axes: l’agent fluorescent, le vert d’indocyanine, et les caméras NIR / In our work of PhD, we endeavored to answer this question: do we can improve tumor resectability in the liver and peritoneal metastases of colorectal cancer? For this, we relied on two elements: the fluorescence of indocyanine green and its detection by NIR camera. Initially, after formal laboratory development, we applied this technique to liver resections. We have shown that this technique has two advantages: the detection of tumor lesions and improving the margin of oncologic resection. The still open question is the percentage of cancerous or precancerous cells present in the fluorescent ring. Secondly, we applied this technique in peritoneal carcinomatosis. This is a first feasibility study because we did not find any publications on this topic. We could show similarities with the study on the liver. The fluorescence from ICG can detect tumors of the peritoneum hardly visible to the naked eye through the intensity and quality of the fluorescence. The outlook is focused on two areas: the fluorescent agent, indocyanine green, and NIR cameras
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In vitro Studies of Improvement in Treatment Efficiency of Photodynamic Therapy of Cancers through Near-Infrared/Bioluminescent Activation

Luo, Ting 22 May 2015 (has links)
Cancer is a leading cause of death that affects millions of people across the globe each year. Photodynamic therapy (PDT) is a relatively new treatment approach for cancer in which anticancer drugs are activated by light at an appropriate wavelength to generate highly cytotoxic reactive oxygen species (ROS) and achieve tumor destruction. Compared with conventional chemo- and radiotherapy, PDT can be performed with minimal invasiveness, local targeting and reduced side effects. However, most of the currently available PDT drugs mainly absorb in the visible part of the spectrum, where light penetration depth into human tissues is very limited. Therefore, increasing the treatment depth of PDT has been considered to be an important approach to improve the effectiveness of PDT for treating larger and thicker tumor masses. In this thesis, we present our investigation into the potential of two-photon activated PDT (2-γ PDT), combination therapy of PDT and chemotherapy, and bioluminescence-activated PDT as a means to increase the treatment depth of this modality. In 2-γ PDT, the photosensitizing agents are activated through simultaneous absorption of two photons. This approach allows the use of near-infrared (NIR) light that can penetrate deeper into tissues and thus, has the potential of treating deep-seated tumors and reducing side effects, while the non-linear nature of two-photon excitation (TPE) may improve tumor targeting. We have evaluated the PDT efficacy of a second-generation photosensitizer derived from chlorophyll a, pyropheophorbide a methyl ester (MPPa), through both one- and two-photon activation. We observed that MPPa had high one-photon (1-γ PDT efficacy against both cisplatin-sensitive human cervical (HeLa) and cisplatin-resistant human lung (A549) and ovarian (NIH:OVCAR-3) cancer cells when activated by femtosecond (fs) laser pulses at 674 nm. At a low light dose of 0.06 J cm-2, the MPPa concentration required to produce a 50% cell killing effect (IC50) was determined to be 5.3 ± 0.3, 3.4 ± 0.3 and 3.6 ± 0.4 μM in HeLa, A549 and NIH:OVCAR-3 cells, respectively. More significantly, we also found that MPPa could be effectively activated at the optimal tissue-penetrating wavelength of 800 nm through TPE. At a light dose of 886 J cm-2, where no measurable photodamage was observed in the absence of MPPa, the IC50 values were measured to be 4.1 ± 0.3, 9.6 ± 1.0 and 1.6 ± 0.3 μM in HeLa, A549 and NIH:OVCAR-3 cells, respectively. We obtained corresponding LD50 (the light dose required to produce a 50% killing effect) values of 576 ± 13, 478 ± 18 and 360 ± 16 J cm-2 for 10 μM MPPa, which were approximately 3-5 times lower than the published 2-γ LD50 of Visudyne® and 20-30 times lower than that of Photofrin®. These results indicate that MPPa may serve as a photosensitizer for both 1- and 2-γ activated PDT treatment of difficult-to-treat tumors by conventional therapies. Indocyanine green (ICG), a dye having an absorption maximum near 800 nm, has been considered to be a potential NIR PDT agent. However, the PDT efficacy of ICG has been found to be very limited probably due to the low yield of cytotoxic ROS. In the present work, we have evaluated the combination effects of ICG-mediated PDT with conventional chemotherapy mediated by two types of chemotherapeutic drugs, namely the type II topoisomerase (TOPII) poisons etoposide (VP-16)/teniposide (VM-26) and the platinum-based drugs cisplatin (CDDP)/oxaliplatin (OXP). Synergistic enhancement of cytotoxicity and increased yields of DNA double strand breaks (DSBs) were observed in HeLa, A549 and NIH:OVCAR-3 cancer cells treated with the combination of ICG-PDT and VP-16. The presence of VP-16 during the laser irradiation process was found to be critical for producing a synergistic effect. An electron-transfer-based mechanism, in which ICG could increase the yield of highly cytotoxic VP-16 metabolites, was proposed for the observed synergistic effects, although direct spectroscopic detection of the reaction products was found to be very challenging. Moreover, we observed a much lower degree of synergy in the human normal fibroblast GM05757 cells than that in the three cancer cell lines investigated. Synergistic effects were also observed in A549 cells treated with the combination of ICG-PDT and VM-26 (i.e. an analog of VP-16). Furthermore, the combination of low-dose CDDP/OXP and ICG-PDT was demonstrated to produce an additive or synergistic effect in selected cancer cell lines. These preliminary results suggest that the combination of ICG-PDT with VP-16/VM-26 or CDDP/OXP chemotherapy may offer the advantages of enhancing the therapeutic effectiveness of ICG-PDT and lowering the side effects associated with the chemotherapeutic drugs. Bioluminescence, the generation of light in living organisms through chemical reactions, has been explored as an internal light source for PDT in recent years. This approach, in principle, does not suffer from the limited tissue penetration depth of light. In the present project, we have evaluated the effectiveness of luminol bioluminescence in activating the porphyrin photosensitizers meso-tetra(4-sulfonatophenyl)porphine dihydrochloride (TPPS4) and Fe(III) meso-tetra(4-sulfonatophenyl)porphine chloride (FeTPPS). The combination treatment induced significant killing of HeLa cells, while additive effects were observed in two normal human fibroblast cell lines (GM05757 and MRC-5). Our observations indicate that bioluminescence of luminol may generate sufficient light for intracellular activation of PDT sensitizers. Furthermore, the combination treatment may have intrinsic selectivity towards cancerous tissues. In summary, we have demonstrated effective killing of cancer cells by MPPa-mediated 1- and 2-γ PDT, combination of ICG-PDT and VP-16/VM-26 or CDDP/OXP chemotherapy, and bioluminescence of luminol activated PDT mediated by TPPS4/FeTPPS. These positive preliminary results indicate that all these three approaches have the potential of increasing the treatment depth of PDT and facilitating the development of more effective PDT treatment strategies.

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