Open AccessLimiting factors to the OCT axial resolution for in-vivo imaging of human and rodent retina in the 1060nm wavelength range
Author(s) -
Sanaz Hariri,
Alireza Akhlagh Moayed,
Aphrodite Dracopoulos,
Chulho Hyun,
Shelley Boyd,
Kostadinka Bizheva
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.024304
Subject(s) - optical coherence tomography , optics , retina , human eye , retinal , wavelength , materials science , preclinical imaging , resolution (logic) , image resolution , refractive index , physics , in vivo , chemistry , biology , biochemistry , microbiology and biotechnology , artificial intelligence , computer science
A computational model was developed to evaluate the limitations to the highest axial resolution, achievable with ultrahigh resolution optical coherence tomography (UHROCT) in the 1060 nm wavelength region for in-vivo imaging of the human and rodent retina. The model considers parameters such as the wavelength dependent water absorption, the average length of the human and rodent eyes, and the power limitations for the imaging beam as defined in the ANSI standard. A custom-built light source with re-shaped spectrum was used to verify experimentally the results from the computational model. Axial OCT resolution of 4.2 microm and 7.7 microm was measured from a mirror reflection with the custom light source by propagating the imaging beam through water cells with 5 mm and 25 mm thickness, corresponding to the average axial length of the rodent and human eye respectively. Assuming an average refractive index of 1.38 for retinal tissue, the expected axial OCT resolution in the rodent and human retina is 3 microm and 5.7 microm respectively. Retinal tomograms acquired in-vivo from the rat eye with the modified light source show clear visualization of all intraretinal layers, as well as a network of capillaries (approximately 10 microm in diameter) in the inner- and outer plexiform layers of the retina.