TY - JOUR
T1 - A Model for the Effect of Disturbances in the Optical Media on the OCT Image Quality
AU - Kok, Pauline H. B.
AU - van Dijk, Hille W.
AU - van den Berg, Thomas J. T. P.
AU - Verbraak, Frank D.
PY - 2009
Y1 - 2009
N2 - PURPOSE. The loss of quality of optical coherence tomography (OCT) images resulting from disturbances in the optical media has been modeled. METHODS. OCT measurements were performed in two healthy volunteers using time domain (TD)-OCT (StratusOCT; Carl Zeiss Meditec, Dublin, CA). Optical disturbances were approached in three ways simulated with filters. The studied effects were: light attenuation (absorptive and reflective filters), refractive aberrations (defocusing lenses), and light scattering/straylight (scattering filters). The same examiner scanned the subjects with the filters placed in front of the eye. The signal strength (SS) values of the scans were then collected. The strength of the filters were expressed in optical density (OD), determined for the 830 nm central wavelength of the OCT, (OD lambda=830). RESULTS. A linear relationship has been found between the OD lambda=830 of the absorptive and reflective filters and the SS of the corresponding OCT images. Assuming that reduction of light from the OCT scanning spot on the retina is the critical factor, this light loss was determined for the scattering filters and defocusing lenses. A comparable linear relationship was found between the SS value and the OD lambda=830 of these filters. CONCLUSIONS. The model indicates that the loss of OCT image quality in patients with disturbances in the optical media is explained by attenuation of the light in the OCT scanning spot on the retina. A linear relationship between the SS and the single pass logarithmic attenuation of the OCT signal is shown, according to SS = constant-(9.9 [-9.4 to-10.6] . OD lambda=830). (Invest Ophthalmol Vis Sci. 2009;50:787-792) DOI:10.1167/iovs.08-2364
AB - PURPOSE. The loss of quality of optical coherence tomography (OCT) images resulting from disturbances in the optical media has been modeled. METHODS. OCT measurements were performed in two healthy volunteers using time domain (TD)-OCT (StratusOCT; Carl Zeiss Meditec, Dublin, CA). Optical disturbances were approached in three ways simulated with filters. The studied effects were: light attenuation (absorptive and reflective filters), refractive aberrations (defocusing lenses), and light scattering/straylight (scattering filters). The same examiner scanned the subjects with the filters placed in front of the eye. The signal strength (SS) values of the scans were then collected. The strength of the filters were expressed in optical density (OD), determined for the 830 nm central wavelength of the OCT, (OD lambda=830). RESULTS. A linear relationship has been found between the OD lambda=830 of the absorptive and reflective filters and the SS of the corresponding OCT images. Assuming that reduction of light from the OCT scanning spot on the retina is the critical factor, this light loss was determined for the scattering filters and defocusing lenses. A comparable linear relationship was found between the SS value and the OD lambda=830 of these filters. CONCLUSIONS. The model indicates that the loss of OCT image quality in patients with disturbances in the optical media is explained by attenuation of the light in the OCT scanning spot on the retina. A linear relationship between the SS and the single pass logarithmic attenuation of the OCT signal is shown, according to SS = constant-(9.9 [-9.4 to-10.6] . OD lambda=830). (Invest Ophthalmol Vis Sci. 2009;50:787-792) DOI:10.1167/iovs.08-2364
U2 - https://doi.org/10.1167/iovs.08-2364
DO - https://doi.org/10.1167/iovs.08-2364
M3 - Article
C2 - 18775857
SN - 0146-0404
VL - 50
SP - 787
EP - 792
JO - Investigative Ophthalmology & Visual Science
JF - Investigative Ophthalmology & Visual Science
IS - 2
ER -