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A dynamic opto-physiological model to effectively interpret retinal microvascular circulation

conference contribution
posted on 23.03.2016, 09:38 by Harnani Hassan, Sijung HuSijung Hu, Vincent Dwyer
The demand of non-invasive ocular screening is rapidly growing due to an increase of age related eye diseases worldwide. An indeed in-depth understanding of optical properties is required to elucidate nature of retinal tissue. The research aims to investigate an effective biomedical engineering approach to allow process region of interests (ROIs) in eyes to reveal physiological status. A dynamic opto-physiological model (DOPM) representing retinal microvascular circulation underlying a diffusion approximation to solve radiative transport theorem (RTT) has being developed to interpret patho-physiological phenomena. DOPM is being applied in imaging photoplethysmography (iPPG) to extract PPG signals from a series of 2D matrix images to access blood perfusion and oxygen saturation distributions. A variation of microvascular circulation could be mapped for an effectively diagnostic screening. The work presents mathematical modelling based ten layers of ocular tissue tested with four set of controlled parameters demontrated detection ratio between normal tissue damage or abnormal tissue and significant change of AC signal amplitude in these tissues. The result shows signicant change of AC signal amplitude in abnormal tissue. The preliminary results show extractable PPG signals from eye fundus video; experimented at five ROIs: whole fundus, optical disk, main vein vessel, lesion area and affected area. The outcome shows optical disk region gave a better performance compared to whole fundus region and main vein vessel. The robustness, miniaturization and artefact reduction capability of DOPM to discriminate oxygenation levels in retina could offer a new insight to access retinal patho-physiological status.


The authors would like to express their deepest gratitude to Loughborough University and MajlisAmanah Rakyat (MARA) who provided financial support for this project. Also, the authors would like to acknowledge the support of the Marie Curie International Research Staff Exchange Scheme (IRSES) Project – “Micro-Multi-Material-Manufacture to Enable Multifunctional Miniaturized Devices (M6)”.



  • Mechanical, Electrical and Manufacturing Engineering

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Conference on Design and Quality for Biomedical Technologies VIII Design and Quality for Biomedical Technologies VIII




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HASSAN, H., HU, S. and DWYER, V.M., 2015. A dynamic opto-physiological model to effectively interpret retinal microvascular circulation. Proceedings of SPIE, 9315, DOI: 10.1117/12.2076899.




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