The Quantitative Analysis of Autofluorescence in the Aging Crystalline Lens

When illuminated by blue light, the human crystalline lens exhibits green autofluorescence. Autofluorescence of the human lens were analyzed quantitatively in vivo as a function of age in 75 healthy individuals{150 eyes) without cataract, ranging in age from 17 to 63 years. Lenses were scanned through the dilated pupil along the optical axis, generating a fluorescence profile consisting of anterior and posterior peaks of lens, using an automated scanning fluorophotometer(Fluorotron master) coupled with a lens system designed for high resolution of the anterior segment structures. Anterior peak autofluorescence increased linearly by 90 ng fluorescein/ml per decade and posterior peak autofluorescence by 70 ng fluorescein/ml per decade. No significant difference between right and left eyes was demonstrated for anterior or posterior peak autofluorescence. We suggest that the quantitative analysis of the autofluorescence of the human lens might be useful to investigate the changes of the aging lens proteins and the pathogenesis of cataract.

Comparison of The Effects of Healon(R) and BioLon(R) on Rabbit Eyeballs after Intracameral and Intravitreal Injections

We conducted a study to compare the effects of Healon(R) and BioLon(R), which are sodium hyaluronates made by different raw materials, on rabbit eyeballs after intracameral and intravitreal injections. In the intracameral-injection group, aqueous humor was replaced with 0.2 ml of Healon(R) or BioLon(R), and in the intravitreal-injection group. 0.4 ml of Healon(R) or BioLon(R) was injected after the removal of the same amount of vitreous. Slitlamp and indirect ophthalmoscopic examination, measurement of IOP, and measurement of corneal thickness were performed preoperatively and at 2hours, 24 hours, 3 days, and 7 days postoperatively. Histopathologic examinaion was done at 7 days postoperatively. No group had significant differences in all tests(p>0.05) and the findings were normalized within 7 days. These results indicated that there were no significant differences between the Healon(R) and BioLon(R) groups in the effects on rabbit eyeballs after intracameral and intravitreal injections.

The Relationship between Diabetic Retinopathy and Corneal Autofluorescence

The metabolic changes in diabetics result in progressive retinopathy and influence corneal metabolism. Changes in corneal autofluorescence were demonstrated originating from mitochondrial flavoproteins and influenced by the metabolic changes in cornea in diabetics. The corneal autofluorescence was determined to evaluate its correlation with diabetic retinopathy using fluorophotometer in 25 healthy controls, 25 diabetic mellitus(DM) pationts without retinopathy, 25 background diabetic retinopathy(BDR)patients, 25 preproliferative diabetic retinopathy (PPDR) patients, and 25 proliferative diabetic retinopathy(PDR) patients. The mean values(mean +/- standard deviation in ng fluorescein/ml) were 13.9 +/- 1.9, 18.7 +/- 3.1, 19.6 +/- 2.3, 20.2 +/- 4.0, 24.3 +/- 4.2, respectively. The means of coreal autofluorescence values in diabetics were significantly higher than that of the healthy controls(p0.05), but the mean value in PDR patients was significantly higher than those of the other 4 groups(p<0.001). These results indicate that measurement of corneal autofluorescence can play a supplementary role in diagnosing diabetic retinopathy.