[In vivo changes in epithelial cells following PEA using the lenses of albino rabbits].

In this study, the changes in epithelial cells and the lens capsules of the eyes of albino rabbits which were subjected to phacoemulsification and aspiration (PEA) with or without intraocular lens (IOL) implantation were histopathologically evaluated. In the rabbits without implantation of IOLs, Soemmerring's ring was observed more frequently, and many fusiform cells reappeared in the junction between a section of the anterior lens capsule and the posterior lens capsule. Folding in the posterior lens capsule increased over time. When IOLs were implanted, the IOLs successfully inhibited Soemmerring's ring formation. However some lens fibers still proliferated between the IOL and lens capsule. Fusiform cell growth was observed adjacent to the anterior lens capsule, but cells did not extend across the lens surface. Epithelial cells were found to cover nearly the entire surface of the posterior capsule, causing opacity of capsule. These experiments indicated that after cataracts resulted from the proliferation of lens epithelial and fusiform cells, and folds induced by contraction.

Case-control study of senile cataract in Japan: a preliminary report.

A hospital-based case-control study of senile cataract was conducted in Japan from 1988 to 1990. Two hundred and twelve patients with senile cataract and 212 control subjects with the same age-sex distribution were interviewed and given an ophthalmological examination. Both groups were randomly selected outpatients from 9 hospitals. Associations between senile cataract and four groups of variables, factors regarded as risks, life style habits, general aging indices or other factors were analyzed, and the data was subjected to statistical analysis. An increased risk of cataract was found in males who were presently spending 7 hours or more outside daily (Odds ratio = 5.07) and in females with 4 or fewer remaining teeth (Odds ratio = 2.03). The findings from this study suggest that there may be a sex-related host sensitivity or life style which is predisposing to the development of senile cataract.

Classification system for cataracts. Application by the Japanese Cooperative Cataract Epidemiology Study Group.

A cataract classification and grading system for the main purpose of cataract epidemiological studies is proposed by the Japanese Cooperative Cataract Epidemiology Study Group. Cataractous types are classified principally into cortical, nuclear and subcapsular opacities. Stages of cataract advancement are classified into grade I (early stage), grade II (moderate stage) and grade III (advanced stage). Regarding cortical opacities an opacified area obtained from red-reflex images is utilized for grading judgment. Nuclear opacity grading is based on the intensity of scattering at the nucleus. Grading of subcapsular opacities is judged from their extension in the three different pupillary areas. To help grading judgments, standard pictures of cortical and nuclear cataracts are provided. Gradings of lens coloration are divided into pale yellow (grade I), yellow (II), brownish yellow (III) and brown including reddish and black brown (IV). A recording chart is also provided.

[A cataract classification and grading system].

A cataract classification and grading system developed for cataract epidemiological survey was introduced. Cataractous opacities were classified into cortical, nuclear and subcapsular types. Gradings of cataract progression were divided into early (Grade I), moderate (II) and advanced (III) stages. The grading of cortical opacity was judged by the opaque area in a maximally dilated pupillary zone of which findings were obtained from a red-reflex image. The grading of nuclear opacity was judged from the intensity of scattering light at the nucleus. Three grading steps were based on the densitometrical analysis of photographed images. Subcapsular opacities were classified into three gradings by extensions up to the normal, moderately dilated and maximally dilated pupil size. Regarding cortical and unclear cataracts, standard images indicating border findings between Grades I and II and Grades II and III were provided to help with classification. Nuclear coloration was classified into pale yellow, yellow, brownish yellow and brown including reddish brown and black brown. To document cataractous findings, a recording chart was made.

Increased glycosylation of proteins from cataractous lenses in diabetes.

The rates of glycosylation of lens proteins were determined in extracts of human 'diabetic' and 'senile' cataractous lenses by a method employing thiobarbituric acid. Incubation of soluble lens proteins (6,500 X g supernatant of homogenates) in vitro with various concentrations of D-glucose in sodium phosphate buffer (50 mmol/l, pH 7.2) resulted in a gradual glycosylation which was time and concentration dependent. Glycosylated proteins from the cataractous lenses of 21 senile and 12 diabetic subjects afforded 0.72 +/- 0.22 and 1.84 +/- 0.44 nmol 5-hydroxymethylfurfural/mg protein (mean +/- SD), respectively. The value is significantly higher in the diabetic than in the senile group (p less than 0.001), although the mean age of the diabetic patients (67 years) was significantly younger than that of senile subjects (75 years; p less than 0.01). These results indicate that human lens proteins can be glycosylated both in vitro and in vivo, and that hyperglycaemia can accelerate the non-enzymatic glycosylation of lens proteins in diabetic patients.