Potentials and Limits of Modern Optical Instruments for the Non-Invasive Investigation of The Anterior Eye Segment

ABSTRACT

 Considerabel progress has been made in the development and design of optical instruments that allow precise measurements of the morphological and also physiological properties of the transparent media of the eye namely the cornea and the lens.  Cameras that are built according to the Schemipflug principle (Topcon SL-45, Zeiss SLC, Oxford Case 2000, Nidex EAS 1000) allow precise measurements of light scattering and biometrical parameters of the cornea and the lens.  Cataracts can be monitored with respect to their location, development and progress, so that also prospective experimental and epidemiological data are obtained.  The technique of retroilumination, which is already implemented in the Case 2000 and the EAS 1000, can provide additional information but on its own did not prove to be reliable for clinical studies.  At the moment, new diagnostic fields are opened with the application of laser light scattering combined with the confocal principle to the measurement of scattering, fluorescence and absorption in the eye.  These techniques carry the potential to measure the dynamics of physiological processes in the tissue as well as the distribution of drugs.