Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina
Autor(a) principal: | |
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Data de Publicação: | 2015 |
Tipo de documento: | Dissertação |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10362/15618 |
Resumo: | The Stiles-Crawford effect (SCE) is the well-known phenomenon in which the brightness of light perceived by the human eye depends upon its entrance point in the pupil. This physiological characteristic is due to the directional sensitivity of the cone photoreceptors in the retina and it displays an approximately Gaussian dependency which is altered in a number of pathologies. Retinal imaging, a widely spread clinical practice, may be used to evaluate the SCE and thus serve as diagnostic tool. Nonetheless, its use for such a purpose is still underdeveloped and far from the clinical reality. In this project a fundus camera was built and used to assess the cone photoreceptor directionality by reflective imaging of the retina in healthy individuals. The physical and physiological implications of its development are addressed in detail in the text: the optical properties of the human eye, illumination issues, acquiring a retinal image formed by the eye, among others. A full description of the developmental process that led to the final measuring method and results is also given. The developed setup was successfully used to obtain high quality images of the eye fundus and in particular the parafoveal cone photoreceptors. The SCE was successfully observed and characterized. Even though considerable improvements could be done to the measurement method, the project showed the feasibility of using retinal imaging to evaluate the SCE thus motivating its usage in a clinical environment. |
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Development of a fundus camera for analysis of photoreceptor directionality in the healthy retinaEyeStiles-crawford effectCone photoreceptorsRetinal imagingDomínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e TecnologiasThe Stiles-Crawford effect (SCE) is the well-known phenomenon in which the brightness of light perceived by the human eye depends upon its entrance point in the pupil. This physiological characteristic is due to the directional sensitivity of the cone photoreceptors in the retina and it displays an approximately Gaussian dependency which is altered in a number of pathologies. Retinal imaging, a widely spread clinical practice, may be used to evaluate the SCE and thus serve as diagnostic tool. Nonetheless, its use for such a purpose is still underdeveloped and far from the clinical reality. In this project a fundus camera was built and used to assess the cone photoreceptor directionality by reflective imaging of the retina in healthy individuals. The physical and physiological implications of its development are addressed in detail in the text: the optical properties of the human eye, illumination issues, acquiring a retinal image formed by the eye, among others. A full description of the developmental process that led to the final measuring method and results is also given. The developed setup was successfully used to obtain high quality images of the eye fundus and in particular the parafoveal cone photoreceptors. The SCE was successfully observed and characterized. Even though considerable improvements could be done to the measurement method, the project showed the feasibility of using retinal imaging to evaluate the SCE thus motivating its usage in a clinical environment.Vohnsen, BrianVieira, PedroRUNAnjos, Pedro Filipe dos Santos2015-10-13T16:24:03Z2015-032015-102015-03-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://hdl.handle.net/10362/15618enginfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2024-03-11T03:51:51Zoai:run.unl.pt:10362/15618Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T03:22:39.581661Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina |
title |
Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina |
spellingShingle |
Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina Anjos, Pedro Filipe dos Santos Eye Stiles-crawford effect Cone photoreceptors Retinal imaging Domínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e Tecnologias |
title_short |
Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina |
title_full |
Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina |
title_fullStr |
Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina |
title_full_unstemmed |
Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina |
title_sort |
Development of a fundus camera for analysis of photoreceptor directionality in the healthy retina |
author |
Anjos, Pedro Filipe dos Santos |
author_facet |
Anjos, Pedro Filipe dos Santos |
author_role |
author |
dc.contributor.none.fl_str_mv |
Vohnsen, Brian Vieira, Pedro RUN |
dc.contributor.author.fl_str_mv |
Anjos, Pedro Filipe dos Santos |
dc.subject.por.fl_str_mv |
Eye Stiles-crawford effect Cone photoreceptors Retinal imaging Domínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e Tecnologias |
topic |
Eye Stiles-crawford effect Cone photoreceptors Retinal imaging Domínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e Tecnologias |
description |
The Stiles-Crawford effect (SCE) is the well-known phenomenon in which the brightness of light perceived by the human eye depends upon its entrance point in the pupil. This physiological characteristic is due to the directional sensitivity of the cone photoreceptors in the retina and it displays an approximately Gaussian dependency which is altered in a number of pathologies. Retinal imaging, a widely spread clinical practice, may be used to evaluate the SCE and thus serve as diagnostic tool. Nonetheless, its use for such a purpose is still underdeveloped and far from the clinical reality. In this project a fundus camera was built and used to assess the cone photoreceptor directionality by reflective imaging of the retina in healthy individuals. The physical and physiological implications of its development are addressed in detail in the text: the optical properties of the human eye, illumination issues, acquiring a retinal image formed by the eye, among others. A full description of the developmental process that led to the final measuring method and results is also given. The developed setup was successfully used to obtain high quality images of the eye fundus and in particular the parafoveal cone photoreceptors. The SCE was successfully observed and characterized. Even though considerable improvements could be done to the measurement method, the project showed the feasibility of using retinal imaging to evaluate the SCE thus motivating its usage in a clinical environment. |
publishDate |
2015 |
dc.date.none.fl_str_mv |
2015-10-13T16:24:03Z 2015-03 2015-10 2015-03-01T00:00:00Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10362/15618 |
url |
http://hdl.handle.net/10362/15618 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
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1799137864919810048 |