Measurement of correlation between transmission and scattering during wound healing in hen corneas

Abstract

The aim of this work is to provide experimental data for corneal transparency and scattering to help create a more complete model of corneal transparency. The scattered light in 96 healing hen corneas was measured for three wavelengths by a scatterometer constructed in the Optics Laboratory (The University of Valladolid, Spain). With the help of mirrors and beamsplitters, the light from the three lasers is directed toward the cell containing the sample to be measured. The measured scattered light varies between six orders of magnitude. Corneal transmissivity, mean cosine of a scattering angle, and angular distribution of scattered light were all computed. The total transmitted light remained practically constant over a wide range of light values transmitted in a forward direction (direct transmissivity). The value of the mean cosine of the scattering direction is very close to the unit (), even in corneas with high opacities. The behavior of g indicates that even damaged corneas evidence extremely small scattering, compared to other biological tissues. The transmission reduction of each cornea is related to an increase in scattered light. In all cases, scattered light is concentrated at very small angles. This behavior is acceptable in corneas that are healthy or which evidence small lesions, but remains in corneas that are severely injured.

Keywords:

• scattering
• optical parameters
• cornea
• wound healing
• hens

Acknowledgements

We would like to thank Dr J.A. Aparicio, V.R. Gonzalez, G. Rodriguez, S. Najera, and S. Gonzalez for their collaboration. This work was supported in part by grant FIS-PI:01/0270 and Red Temática de Investigación Cooperativa en Oftalmología CO3/13, Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo, Madrid, Spain. Alcon-Cusi SA (Barcelona, Spain) donated the experimental excimer laser.