Light scattering in the human lens in childhood and adolescence.

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(R). 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.

Ten years of cataract epidemiology studies in the Department of Experimental Ophthalmology, 1980-1990.

The knowledge of the multifactorial genesis of the so-called senile cataract has initiated an intensified search for cataract-related risk factors. The mechanisms of syn- and cocataractogenesis could already be shown in the Department of Experimental Ophthalmology, Bonn, in the seventies. Subsequently, cataract epidemiology became a field of interest in 1980 when all available epidemiological data related to cataract research were first collected and reviewed. It has become obvious that the various types of cataract morphology do not represent one unique disease 'senile cataract' but reflect different biochemical characteristics. A preliminary study assigned data of case history as well as blood and lens biochemistry to four types of lens opacity. Scheimpflug photography and multilinear microdensitometry were the basis for classifying cataract lenses. After increasing the number of involved patients, the data were analyzed by means of multivariate statistics. The originally used cataract classification system was enlarged to eight types of frequently seen cataract morphologies. A control group was built up to enable case-control studies as well as to obtain characteristics of normal lens density related to age.

[Aspects of physiology, pathology and epidemiology of cataract]. / Aspekte zur Physiologie, Pathologie und Epidemiologie der Katarakt.

World Health Organization estimates that 23 million people have a visual acuity of 0.05 or less. For 12-15 million people cataract is the cause of poor visual acuity or blindness and the majority of those afflicted live in Third World countries. It is estimated that in the year 2025 around 40 million people will become blind due to cataract. The therapeutic procedure of choice is surgical removal of the lens. The high success rate of this procedure in highly industrialized countries has been achieved by the constant improvement in technology and operative technique. This, however, does not hold true for Third World countries. The etiology and pathogenesis of cataract are not yet completely understood. This paper reports on the clinical findings and epidemiology of cataract and deals with the physiology and pathology of the lens. The aim of the study was to recognize possible cataractogenic risk factors. A decrease in the blindness rate caused by cataract in Third World countries can best be achieved through prevention.

[Objectified measurement of eye lens transparency in elderly probands. Results of a Scheimpflug photography study over the course of three and a half years]. / Objektivierte Messung der Augenlinsentransparenz in einer älteren Probandenpopulation. Ergebnisse einer Scheimpflug-Photographischen Studie über einen Zeitraum von 3,5 Jahren.

Lens density has been followed-up in 32 healthy volunteers (mean age 65 years) over a period of 3.5 years. The negatives of Scheimpflug-photos (Topcon SL-45) were evaluated by linear microdensitometry in three measure planes (Joyce Loebl 3 CS). Correlation coefficients, curves of regression as well as calculations of the percentage of density change made obvious, that a minimal increase in lens density occurred in the anterior cortical region.

[Ocular side effects of drugs]. / Arzneimittelnebenwirkungen am Auge.

Drug-induced side effects manifested by the human eye are characterised by the specific anatomical, histological and functional features of the eye. Such ocular changes may arise after local or systemic drug application. The following article outlines the clinically relevant common drug-related side effect on the lids, cornea, conjunctiva, lens, retina, uvea, and the optic nerve, as well as effects on the intraocular pressure, refraction and accommodation.

Objectified measurements of eye lens transparency in a volunteer group of advanced age, carried out over a period of 3.5 years. Results of a Scheimpflug-photographic study.

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.

Scheimpflug photography in clinical ophthalmology. A review.

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 safety study with Picumast dihydrochloride--a double masked study using the Scheimpflug method.

A double-masked study was performed to investigate a possible side effect of the antiallergic substance Picumast dihydrochloride on lens transparency. 372 patients with Picumast dihydrochloride- or Ketotifen-treatment regularly underwent ophthalmologic examinations and Scheimpflug photography of the anterior eye segment. Results of slitlamp examinations as well as microdensitometric analyzes of the film negatives after one year treatment did not reveal any evidence that Picumast dihydrochloride compromised lens transparency in humans.