The age-related increase in normal light scattering in the adult human lens has frequently been documented with Scheimpflug imaging techniques. There are only insufficient data on lens light scattering, however, from the first 2 decades of human life. After having obtained informed consent from their parents, the anterior eye segments of 26 children of both genders were documented with a Topcon SL-45 Scheimpflug camera on Kodak Tmax 400 ASA black-and-white film in 3 meridians. The age of the children, who had either a normal visual acuity or best corrected visual acuity, ranged from 4 to 18 years. Thirty minutes prior to photography, maximal mydriasis was induced by 3-fold instillation of Mydriaticum Roche^®. Parallel to the Scheimpflug photographic documentation, all eyes were subjected to a basic ophthalmological examination. All images obtained were evaluated with microdensitometry as described earlier. The density data in young children demonstrate that there is very little light scattering in the central lens parts and only a faint zone of discontinuity apart from the 2 signals caused by the anterior and posterior capsules. Starting at the age of 14–15 years, the first separations occur in the zones of discontinuity, thus the first age-correlated increase in light scattering. The data obtained demonstrate that the development of light scattering in the young lens differs from that in the adult lens. Our results point to the assumption that the development of protein light scattering in the lens correlates with physical life-time of the individual and not with the period of life in different species with various life expectancies.

The development of a slitlamp camera system based on the Scheimpflug principle with image analysis has been a major improvement in lens and cataract research. Since its introduction into ophthalmology by Brown and Niesel in the sixties of this century and further technical amelioration by Hockwin, Dragomirescu and Sasaki it has been applied in various experimental and clinical investigations. The purpose of this paper is to summarize and review the application of Scheimpflug photography in clinical ophthalmology and to show possibilities and indications for the use of the Scheimpflug technique in clinical studies.

Lens and cataract research from a clinical, biophysical, biological and mainly biochemical point of view has a long tradition. Already since the beginning of the 20th century research relating to the chemical composition and metabolism of the lens was conducted. With these analyses an attempt was made to understand the existence and maintenance of lens transparency and the mechanisms leading to lens opacities. Around the middle of the century the stationary analyses measuring the content of certain substances in the lens were more and more replaced by the search for dynamic metabolic processes responsible for lens growth, maintenance of transparency and possibly active participation in lens function (such as accommodation). Also the disturbances as a result of ageing or the formation of lens opacities have been investigated and resulted partially in the elucidation of reaction chains, leading from a trigger to the formation of a cataract. Lens biochemistry is no longer a closed book to us, but there are still many question marks. Why were we not able to solve more problems around lens and cataract? The research effort with a remarkable financial input and a great number of scientists worldwide during the second half of the century does not correspond to the results obtained. There must be something wrong with our strategy, our interpretation of the results or even both. We would like to stress some points which might be regarded as errors or misunderstandings in the lens research community, thus preventing a better outcome of the enormous investment of work and money. A great disadvantage is the missing cooperation between clinicians and epidemiologists on one hand and basic lens researchers on the other. Especially the ignorance of basic researchers regarding the clinical problems of the lens and of cataracts might be to blame for several 'errors and misunderstandings'. It is not even so long ago since the slitlamp microscope examination of animals belonged to the essential standard methods of a lens research team. Another disadvantage still is the use of the general diagnosis 'cataract' by the clinicians without further classification of the topography of the opacification, which supports the concept that all cataracts have the same trigger mechanism. But most regrettable is the fact that many clinicians have never been really interested in basic research of the lens, in cataract pathogenesis and epidemiology of risk factors or in testing the efficacy of cataract-preventing medication. Their main goal was cataract surgery. On the basis of the success of the cataract surgery at the present time clinicians have even developed the opinion that lens and cataract research is no longer necessary to overcome cataract blindness. But as we all know this refers only to highly industrialized countries; millions of cataract-blind people are still without such help and a change of this condition is not in sight. In our opinion lens and cataract research is still necessary and it will be more successful if we bear in mind th...

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The present study deals with a prospective investigation on the optical density of the eye lenses of 32 volunteers with initially normal eyes (mean age 65 years) over a period of 3.5 years. The negatives of the Scheimpflug photographs (Topcon SL-45) were evaluated by linear densitometry in 3 measure planes (Joyce Loebl 3CS). The evaluation of the coefficient of correlation, the representation of the regression straight line as well as the evaluation of the percent changes in lens density showed that during the observation period of 3.5 years a minimum increase in density took place mainly in the anterior cortex.