TY - JOUR
T1 - In-vitro recording of forward light-scatter by human lens capsules and different types of posterior capsule opacification
AU - van Bree, Maartje C J
AU - van der Meulen, Ivanka J E
AU - Franssen, Luuk
AU - Coppens, Joris E
AU - Zijlmans, Bart L M
AU - van den Berg, Thomas J T P
N1 - Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.
PY - 2012/3
Y1 - 2012/3
N2 - The purpose of the present study was to elucidate the effect of posterior capsule opacification (PCO) on the straylight domain of visual function. PCO is heterogeneous with regard to morphology and severity; both aspects contribute to its functional effect. The isolated impact of capsule areas with specific morphology and severity on straylight was studied in-vitro by recording forward light-scatter. Forward light-scatter by four different capsule types, i.c. anterior capsule (AC), clear posterior capsule (PC), fibrotic and regeneratory PCO, was recorded at several visual angles with a goniometer, using different wavelengths. Angular (θ(a)) and wavelength dependencies (λ(b)) were studied by determining exponents a and b. Recorded straylight values of isolated capsule areas varied between 10× below to 10× above the value normal for the human eye, depending on the capsule's condition (clear to opacified). The angular dependence of light scattered by clear PCs was weaker, whereas in the other capsule types it was stronger than in the normal eye. On average, the wavelength dependence of light scattered by different capsule types was similar, but the variation was considerable. At the smallest visual angles, increased angular and decreased wavelength dependence was found, especially in fibrotic and regeneratory PCO. It was concluded that the range of straylight values found in-vitro in lens capsules properly corresponded to that found previously in in-vivo pseudophakics. Surprisingly, the wavelength dependence of PCO indicated that small-particle light-scattering is important in PCO. Refractile effects were more important at small visual angles, as indicated by the combined stronger angular and weaker wavelength dependence.
AB - The purpose of the present study was to elucidate the effect of posterior capsule opacification (PCO) on the straylight domain of visual function. PCO is heterogeneous with regard to morphology and severity; both aspects contribute to its functional effect. The isolated impact of capsule areas with specific morphology and severity on straylight was studied in-vitro by recording forward light-scatter. Forward light-scatter by four different capsule types, i.c. anterior capsule (AC), clear posterior capsule (PC), fibrotic and regeneratory PCO, was recorded at several visual angles with a goniometer, using different wavelengths. Angular (θ(a)) and wavelength dependencies (λ(b)) were studied by determining exponents a and b. Recorded straylight values of isolated capsule areas varied between 10× below to 10× above the value normal for the human eye, depending on the capsule's condition (clear to opacified). The angular dependence of light scattered by clear PCs was weaker, whereas in the other capsule types it was stronger than in the normal eye. On average, the wavelength dependence of light scattered by different capsule types was similar, but the variation was considerable. At the smallest visual angles, increased angular and decreased wavelength dependence was found, especially in fibrotic and regeneratory PCO. It was concluded that the range of straylight values found in-vitro in lens capsules properly corresponded to that found previously in in-vivo pseudophakics. Surprisingly, the wavelength dependence of PCO indicated that small-particle light-scattering is important in PCO. Refractile effects were more important at small visual angles, as indicated by the combined stronger angular and weaker wavelength dependence.
KW - Capsule Opacification/pathology
KW - Glare
KW - Gonioscopy
KW - Humans
KW - Light
KW - Posterior Capsule of the Lens/radiation effects
KW - Scattering, Radiation
U2 - 10.1016/j.exer.2011.12.008
DO - 10.1016/j.exer.2011.12.008
M3 - Article
C2 - 22197751
SN - 0014-4835
VL - 96
SP - 138
EP - 146
JO - Experimental Eye Research
JF - Experimental Eye Research
IS - 1
ER -