Eccentric fixation patterns, clinical findings, and reading speed in patients with bilateral toxoplasmic macular retinochoroiditis / Padrões de fixação excêntrica, achados clínicos e velocidade de leitura em pacientes com retinocoroidite macular bilateral por toxoplasmose

ABSTRACT Purpose: To study visual acuity, refractive errors, eccentric fixation, and reading performance in patients with toxoplasmic macular retinochoroiditis. Methods: Twenty-three participants with bilateral toxoplasmic macular retinochoroiditis and 4 with toxoplasmic macular retinocho­roiditis in their unique eye were evaluated. Participants reported their eye dominance, confirmed by the Portus and Miles test. Best corrected visual acuity, spherical equivalent refraction, magnification need, and reading speed were measured. Microperimetry (MAIA, Centervue - Padova, Italy) recorded the preferred retinal locus and fixation stability by means of the bivariate contour ellipse area. Fourteen eyes from 14 normally sighted subjects served as controls. Results: Mean ± SD best corrected visual acuity was better in the dominant eye than in the nondominant eye: 0.9 ± 0.2 (logMAR 0.5 to 1.4) vs. 1.2 ± 0.3 (logMAR 0.6 to 1.7) (p<0.0001, paired t-test). Spherical equivalent myopia of -4.00 or higher was present in 42% of the eyes. Microperimetry was performed in 42 eyes. Eccentric fixation was observed in all examined eyes. In 14 eyes (33%), the preferred retinal locus was placed (in the retina) superior temporal to the macular lesion, in 10 (24%) superior nasal, in 6 (14%) inferior temporal, and in 12 (28%) inferior nasal. There was no significant difference in the distribution of the preferred retinal locus position between dominant and nondominant eyes (p=0.85, Pearson test). There was no correlation between reading speed and the distance between the preferred retinal locus and the estimated original foveal position (r=-0.09; p=0.73), the bivariate contour ellipse area (r=-0.19; p=0.44), or best corrected visual acuity (r=0.024; p=0.92). Conclusions: Myopia is more prevalent in patients with toxoplasmic macular retinochoroiditis. Reading speed is not dependent on preferred retinal locus position, stability, or visual acuity. Nevertheless, documentation of fixation provides new data on the impact of visual impairment in these patients and may be useful for rehabilitation efforts.

RESUMO Objetivo: Estudar a acuidade visual, erros de refração, fixação excêntrica e desempenho de leitura em pacientes com retinocoroidite macular por Toxoplasmose. Métodos: Vinte e três pacientes com retinocoroidite macular por Toxoplasmose bilateral e quatro com retinocoroidite macular por Toxoplasmose no seu único olho foram avaliados. Os participantes relataram sua dominância ocular, confirmada pelo teste de Portus e Miles. A acuidade visual melhor corrigida, refração em equivalente esférico, magnificação necessária e velocidade de leitura foram medidas. A microperimetria (MAIA, Centervue - Padova, Italy) registrou a estabilidade preferida do locus e da fixação da retina por meio da área da elipse de con­torno bivariada. Quatorze olhos de 14 pacientes com boa visão serviram como controles. Resultados: A média ± DP da acuidade visual melhor corrigida foi melhor no olho do­minante do que no não dominante: 0,9 ± 0,2 (logMAR 0,5 a 1,4) vs. 1,2 ± 0,3 (logMAR 0,6 a 1,7) (p<0,0001, teste t pareado). Miopia em equivalente esférico de -4,00 ou maior estava presente em 42% dos olhos. Microperimetria foi realizada em 42 olhos. Fixação excêntrica foi observada em todos os olhos examinados. Em 14 olhos (33%), o locus retiniano preferencial estava localizado, na retina, na região súpero-temporal à lesão macular, em 10 (24%) súpero-nasal, em 6 (14%) ínfero-temporal, e em 12 olhos (29%) ínfero-nasal. Não houve diferença significativa na distribuição da posição do locus retiniano preferencial entre olhos dominantes e não dominantes (p=0,85, teste de Pearson). Não houve correlação entre velocidade de leitura e distância entre o locus retiniano preferencial e a posição foveal original estimada (r=-0,09; p=0,73), a área bivariada de contorno elipsóide (r=-0,19; p=0,44) ou acuidade visual melhor corrigida (r=0,024; p=0,92). Conclusões: A miopia é mais prevalente em pacientes com retinocoroidite macular por Toxoplasmose. A velocidade de leitura não é dependente da posição do locus retiniano preferencial, da estabilidade ou da acuidade visual. A documentação do padrão de fixação excêntrica, entretanto, oferece novos dados no impacto da deficiência visual nesses pacientes e pode ser útil em estratégias de reabilitação.

Eccentric fixation patterns, clinical findings, and reading speed in patients with bilateral toxoplasmic macular retinochoroiditis.

PURPOSE: To study visual acuity, refractive errors, eccentric fixation, and reading performance in patients with toxoplasmic macular retinochoroiditis. METHODS: Twenty-three participants with bilateral toxoplasmic macular retinochoroiditis and 4 with toxoplasmic macular retinocho-roiditis in their unique eye were evaluated. Participants reported their eye dominance, confirmed by the Portus and Miles test. Best corrected visual acuity, spherical equivalent refraction, magnification need, and reading speed were measured. Microperimetry (MAIA, Centervue - Padova, Italy) recorded the preferred retinal locus and fixation stability by means of the bivariate contour ellipse area. Fourteen eyes from 14 normally sighted subjects served as controls. RESULTS: Mean ± SD best corrected visual acuity was better in the dominant eye than in the nondominant eye: 0.9 ± 0.2 (logMAR 0.5 to 1.4) vs. 1.2 ± 0.3 (logMAR 0.6 to 1.7) (p<0.0001, paired t-test). Spherical equivalent myopia of -4.00 or higher was present in 42% of the eyes. Microperimetry was performed in 42 eyes. Eccentric fixation was observed in all examined eyes. In 14 eyes (33%), the preferred retinal locus was placed (in the retina) superior temporal to the macular lesion, in 10 (24%) superior nasal, in 6 (14%) inferior temporal, and in 12 (28%) inferior nasal. There was no significant difference in the distribution of the preferred retinal locus position between dominant and nondominant eyes (p=0.85, Pearson test). There was no correlation between reading speed and the distance between the preferred retinal locus and the estimated original foveal position (r=-0.09; p=0.73), the bivariate contour ellipse area (r=-0.19; p=0.44), or best corrected visual acuity (r=0.024; p=0.92). CONCLUSIONS: Myopia is more prevalent in patients with toxoplasmic macular retinochoroiditis. Reading speed is not dependent on preferred retinal locus position, stability, or visual acuity. Nevertheless, documentation of fixation provides new data on the impact of visual impairment in these patients and may be useful for rehabilitation efforts.

Progress in animal experimentation ethics: a case study from a Brazilian medical school and from the international medical literature.

PURPOSE: This study describes in Brazil and in the global biomedical community the time course of the development of animal research welfare guidelines. METHODS: The database of the Ethics Committee of the Faculty of Medicine of Ribeirao Preto (EC/FMRP-USP), Brazil, was surveyed since its inception in 2002 as the regulations became more stringent to provide better protection of animal research welfare at this institution. Medline database was evaluated to identify the number of publications in the period between 1968 and 2008 that used research animals and were in compliance with established ethics guidelines. RESULTS: The EC/FMRP-USP evaluated 979 projects up until 2009. Most of the applications came from Department of Physiology and the most frequently requested species was the rat. In 2004, national research funding agencies started to request prior approval from institutional review ethics committees prior to application review and this requirement became federal law in Brazil in 2008. The analysis of international publications revealed a relative reduction in studies involving research animals (18% in 1968 to 7.5% in 2008). CONCLUSIONS: The present work showed that in the last four decades major changes occurred in the guidelines dictating use of research animals occurred and they are being adopted by developing countries. Moreover, animal welfare concern in the scientific community preceded the introduction of journal guidelines for this purpose. Furthermore, in Brazil it was anticipated that laws were needed to protect animal research welfare from being not upheld.

Progress in animal experimentation ethics: a case study from a Brazilian medical school and from the international medical literature / Progresso na ética em experimentação animal: o estudo de caso de uma escola médica brasileira e da literatura médica internacional

PURPOSE: This study describes in Brazil and in the global biomedical community the time course of the development of animal research welfare guidelines. METHODS: The database of the Ethics Committee of the Faculty of Medicine of Ribeirao Preto (EC/FMRP-USP), Brazil, was surveyed since its inception in 2002 as the regulations became more stringent to provide better protection of animal research welfare at this institution. Medline database was evaluated to identify the number of publications in the period between 1968 and 2008 that used research animals and were in compliance with established ethics guidelines. RESULTS: The EC/FMRP-USP evaluated 979 projects up until 2009. Most of the applications came from Department of Physiology and the most frequently requested species was the rat. In 2004, national research funding agencies started to request prior approval from institutional review ethics committees prior to application review and this requirement became federal law in Brazil in 2008. The analysis of international publications revealed a relative reduction in studies involving research animals (18% in 1968 to 7.5% in 2008). CONCLUSIONS: The present work showed that in the last four decades major changes occurred in the guidelines dictating use of research animals occurred and they are being adopted by developing countries. Moreover, animal welfare concern in the scientific community preceded the introduction of journal guidelines for this purpose. Furthermore, in Brazil it was anticipated that laws were needed to protect animal research welfare from being not upheld.

OBJETIVO: Caracterizar a evolução da pesquisa com animais no Brasil e na comunidade biomédica mundial. MÉTODOS: O banco de dados do Comitê de Ética da Faculdade de Medicina de Ribeirão Preto (CE/FMRP-USP), Brasil, foi analisado desde a sua criação em 2002, bem como a legislação regulatória para pesquisa com animais no país. As publicações do período de 1968 a 2009 do banco de dados Medline foram avaliadas para identificação do uso de animais em pesquisa e da aderência às regulamentações de ética. RESULTADOS: O CE/FMRP-USP avaliou 979 projetos até 2009, sendo a maioria das solicitações do Departamento de Fisiologia e o rato a espécie mais utilizada. Em 2004, as agências nacionais de incentivo a pesquisa começaram a exigir a aprovação prévia de comitês de ética e este requerimento se tornou Lei Federal no Brasil em 2008. A análise de publicações internacionais revelou uma redução no número de estudo envolvendo pesquisa com animais (18% em 1968 to 7,5% em 2008). CONCLUSÃO: O presente estudo mostrou que, nas últimas décadas, importantes mudanças na regulamentação do uso de animais em pesquisa e estão sendo assimiladas nos países em desenvolvimento. A preocupação com bem estar animal pela comunidade científica precedeu a introdução de regras pelas revistas e, no Brasil, antecipou a regulamentação federal.