BACKGROUND: Using laser speckle flowgraphy to calculate retinal blood flow, we sought to measure changes in optic nerve blood flow compared to the normal fellow eye (relative blood flow) and changes in vision in patients with central retinal artery occlusions of varying duration. METHODS: Laser speckle flowgraphy was used to measure optic nerve blood flow in eyes with central retinal artery occlusions and the normal fellow eye of patients seen at Beth Israel Deaconess Medical Center to calculate relative blood flow. Visual acuity was assessed monocularly using Snellen Charts in a standardized fashion. RESULTS: In healthy control patients (n=20), relative blood flow was calculated to be 1.02 (p= 0.6843), indicating no significant difference in blood flow between eyes. In patients with unilateral central retinal artery occlusions (n=7), relative blood flow was calculated to be 0.66 ± 0.13 (p < .001), indicating on average a 33 percent loss in blood flow through the optic nerve head. When comparing relative blood flow values of CRAO patients measured within one year of vision loss versus patients when measured after one year of reported vision loss, values of patients measured within one year were lower. CONCLUSIONS AND RELEVANCE: Laser Speckle Flowgraphy has been shown to be a useful diagnostic tool that can reliably provide quantitative information on retinal blood flow. Results suggest that blood flow through the optic nerve head does return over time, presumably as the occlusion resolves or recanalizes. Longitudinal analysis determined a higher relative blood flow in patients one-year post incident versus within one year. However no statistically significant difference in visual acuity between these groups was found, indicating that return of blood flow is not associated with a return in visual acuity. Relative blood flow may be a useful measure of retinal perfusion in other retinal vascular disorders.

Orientador: Mauro Willian Barbosa de Almeida / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-19T17:41:36Z (GMT). No. of bitstreams: 1 Niemeyer_Fernando_M.pdf: 5424286 bytes, checksum: a1b57d25166e8f7619af651e5a957e1b (MD5) Previous issue date: 2011 / Resumo: Este trabalho trata dos processos de produção e apropriação da diversidade biológica a partir de um estudo de caso entre os Krahô, grupo jê-timbira dos cerrados do Tocantins. A pesquisa vai em busca das características de um possível sistema agrícola krahô e da estrutura subjacente aos processos de resiliência e transformação deste sistema. Partindo de um olhar estratégico sobre uma aldeia específica - a aldeia Morro-do-Boi - buscamos compreender os processos por meio dos quais plantas, sementes, pessoas e conhecimentos circulam através de complexas redes que envolvem índios, brancos e outros agentes não-humanos. Veremos também como categorias tais como "agrobiodiversidade" e "conhecimento tradicional" passaram a fazer parte do universo krahô, e como elas vêm sendo percebidas e elaboradas por eles no contexto interétnico atual / Abstract: This work addresses the processes of production and appropriation of biological diversity drawing on a case study conducted among the Crao, a ge-timbira group from the Tocantins cerrado. The research seeks to understand the characteristics of the craho agricultural system and the structure that underlies the processes of resilience and transformation of this system. With a strategic look on a specific village - the Morro do Boi village - we seek to understand the processes whereby plants, seeds, knowledge and people move through complex networks involving indians, non-indians and other non-human agents. We will also see how categories such as "agrobiodiversity" and "traditional knowledge" became part of the crao universe, and how they are being perceived and elaborated by them in the current interethnic context / Mestrado / Antropologia Social / Mestre em Antropologia Social

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