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.
Aqueous Humor ; Intravitreal Injections* ; Sodium

PURPOSE: Although the process by which intravitreal perfluorocarbon gas is absorbed is incompletely understood, it is known that considerable absorption of intravitreal perfluorocarbon gas occurs through the aqueous humor. The aim of the study was to evaluate experimentally the effect of topical aqueous humor suppressants on the intravitreal perfluorocarbon gas bubble duration. METHODS: After sulfur hexafluoride and perfluoropropane were injected intravitreally in ten rabbits, we measured the time of gas bubble disappearance in eyes treated with topical aqueous humor suppressants and in those not treated. RESULTS: The mean time(+/-SD) to disappearance of 0.4 cc of sulfur hexafluoride was 6.0+/-0.71 days, which was prolonged to 8.0+/-0.71 days with topical aqueous humor suppressants. The mean time(+/-SD) to disappearance of 0.2 cc perfluoropropane was 14.8+/-0.84 days, while it was prolonged to 22.0+/-1.58 days with topical aqueous humor suppressants. CONCLUSIONS: Sulfur hexafluoride and perfluoropropane intravitreal gas bubbles last longer in rabbit eyes treated with aqueous humor suppressants than in fellow control eyes.
Absorption ; Aqueous Humor* ; Rabbits* ; Sulfur Hexafluoride

It is difficult to analyze the chemical compositions of aqueous humor because of the impossibility of collection of aqueous humor in normal situation, lack of analyzing technique, limited amount of aqueous humor. We measured the glucose concentration of aqueous humor both in cataractous patients with diabetes mellitus and in cataractous patients without diabetes mellitus, thus we compared and analyzed glucose concentration in aqueous humor and correlation between blood glucose con centration and aqueous humor glucose concentration in cataractous patients with diabetes. The mean concentration of glucose in aqueous houmor in diabetics was 92.81 +/- 35.58mg/dl and that of non-diabetics was 53.62 +/- 34.42mg/dl. Aqueous glucose concentration in diabetics was statistically significantly higher than that in non-diabetics.
Aqueous Humor* ; Blood Glucose ; Cataract* ; Diabetes Mellitus ; Glucose* ; Humans

OBJECTIVE: In order to study the mechanism of the aqueous humor circulation and its relationship to the glaucoma macroscopically with engineering methods. METHODS: A dynamistic model was presented, which can be used to simulate the situation and the treatment of the primary open angle glaucoma (POAG). The frame of the model was built based on the ophthalmically accepted feedback mechanism between the aqueous humor circulation and the intraocular pressure (IOP). The transfer functions and the parameters were educed from the analysis of physiological theories, the basic elements of hydrodynamics, and the clinical parameters. The relation between the parameters of the system and the episode mechanism of POAG was discussed. A digital method was used to simulate the Challenge test and some medicines' treatment of POAG, and the results were consistent with clinical observations. RESULTS: The results of simulation illuminate that the model can simulate the mechanism of the aqueous humor circulation and the curative mechanism of some medicines under the physiological condition and the pathological condition of the POAG. CONCLUSION: A few parameters which can hardly be captured with clinical method could be obtained from the model. These parameters can be helpful for the diagnosis and prediction of the curative effect.
Aqueous Humor* ; Diagnosis ; Glaucoma ; Glaucoma, Open-Angle* ; Hydrodynamics ; Intraocular Pressure

The Beta-adrenergic blocker(timolol maleate) decreases intraocular pressure by reducing the production of aqueous humor. Twenty patients scheduled to undergo cataract extraction were induced in study. After timolol maleate administration, we found the increase in the total protein concentration. By double-masked controlled study, 0.5% timolol maleate solution and normal saline were applied topically, and aqueous humor was aspirated during surgery. Total protein concentrations were determined by HPGFC. The total protein concentration as well as the concentration of high, medium and low molecular weight protein were elevated in the timololadministrated group. The relation of the levels of the three different molecular weight classes did not differ significantly between the timolol maleate group and the normal group.
Aqueous Humor* ; Cataract Extraction ; Humans ; Intraocular Pressure ; Molecular Weight ; Timolol*

The effect of 0.25% and 0.5% Timolol on intraocular pressure and concentration in aqueous humor was studied after topical instillation in the white rabbit. The intraocular pressure was measured with pneuma tonometer and the Timolol concentration in aqueous humor was measured with High Preformance Liquid Chromatograph after fine needle aspiration of aqueous humor at various time intervals. The results were as follows; 1. The percentage reduction of intraocular pressure increased with time and reached a peak after 3 hours. 2. The concentration of Timolol in aqueous humor increased with time and reached a peak after 3 hours. 3. There was close correlation between intraocular pressure and Timolol concentration in aqueous humor.
Aqueous Humor* ; Biopsy, Fine-Needle ; Intraocular Pressure* ; Timolol*

The purpose of this paper is to investigate the difference in concentration of 0.53% betamethasone in aqueour humor after betamethasone subconjunctival injection on upper and lower fornix after cataract extraction. A total of 8 rabbits were used. Cataract extractions were performed with the cryoprobe. After 6 hours, 0.53% betamethasone was subconjunctivally in upper fornix of the left eye and injected in lower fornix of the right eye. The control group of 3 rabbits underwent with the same procedures but the without lens delivery. the concentration of 0.53% betamethasone in aqueous humor was measured with HPLC(High Performance Liquid Chromatograph) after fine needle aspiration of aqueous humor. The results obtained were as follows. 1. In 5 eyes of the control group in 3 rabbits, 0.53%betamethasone was injected subconjunctivally on the lower fornix. The mean concentration of 0.53% betamethasone in aqueous humor was 0.544 +/- 0.0818 microgram/ml. 2. After 0.53% betamethasone subconjunctival injection on upper fornix after lens extraction, the mean concentration of 0.53% betamethasone in aqueous humor was 0.318 +/- 0.0117 microgram/ml. 3. After 0.53% betamethasone subconjunctival injection on lower fornix agter lens extraction, the mean concentration of 0.53%betamethasone in aqueous humor was 0.702 +/- 0.0332 microgram/ml. 4. The mean concentration of the betamethasone in aqueous humor after 0.53% betamethasone subconjunctival injection on lower fornix after lens extraction was significantly higher than on upper fornix(p<0.05).
Aqueous Humor* ; Betamethasone* ; Biopsy, Fine-Needle ; Cataract Extraction ; Rabbits

The effects of topical sodium-hyaluronan (Na-HA)on the epithelial healing and aqueous compositions were examined in the repair process of experimen-tal corneal alkali wounds.Corneal alkali wounds were produced in one eye of each rabbit by applying a 5.5 mmround filter paper soaked in 1N NaOH onto the central cornea for 60 seconds.Then the eyes were treated topically with either 1%Na-HA (the treatment group)or a phosphate buffered saline (PBS) (the control group)4 times per day.The epithelial healing was assessed using a quantitative method and the changes of the concentration of ascorbic acid and glucose in aqueous were evaluated.The initial epithelial healing rate was similar between 1%Na-HA treated and control groups and the later healing was enhanced in the treated group but statistically insignificant.The concentrations of ascorbic acid and glucose in aqueous humor are not statistically different in the early phase, but ascorbic acid concentration in later healing phase was higher in the treated group when compared with the control group.The present findings in dicate that topical-ly applied 1%Na-HA affects late epithelial healing and ascorbic acid concentration in aqueous humor during the repair process after corneal alkali wounds.
Alkalies* ; Aqueous Humor ; Ascorbic Acid ; Cornea ; Epithelium ; Glucose ; Wounds and Injuries*

Aqueous humor resembles the serum in composition; its concentration of ascorbic acid, however, measuring to be 15 to 69 times higher (than that of serum) has been presumed to be one of the possible predisposing factors of developing glaucoma. The inhibitor of aqueous humor production, one of the current therapeutic measures of glaucoma has been reported to increase its concentration of ascorbic acid. The effects of Beta-blocker and Acetazolamide on the ascorbic acid concentration are evaluated in this study and further, 50 eyes of 50 cataract patients and 20 eyes of 20 glaucoma patients as the objects, the ascorbic acid concentration in aqueous humor is compared between these two groups under the same pre-set conditions of using the inhibitors. Beta-blocker and acetazolamide elevated the concentration of ascorbic acid by 7.5% and 10.7%, respectively and the combined administration of both resulted in a significant increase of 20.4% (p<0.05). The cataract and glaucoma patients under both medications showed concentrations of 284.7 microgram/ml and 267.3 microgram/ml, each, though, such a slight difference of figure implies no statistical significance. The ascorbic acid concentration in serum and its ratio of composition in aqueous humor and serum does not differ between the two groups. It's concentration in aqueous humor, however, showed a considerable individual variation which was especially remarkable in glaucoma patients. As the conclusion of above evaluations, either ascorbic acid has almost no effect on the pathogenesis of glaucoma or has a similar degree of influence on the pathogenesis of cataract and glaucoma with different mechanisms.
Acetazolamide* ; Aqueous Humor* ; Ascorbic Acid* ; Cataract ; Causality ; Glaucoma ; Humans

PURPOSE: We performed quantitative analysis of aqueous flare to evaluate the influence of diabetes mellitus on the flare values reflecting microvascular injuries of the retina. METHODS: We compared aqueous flare values of diabetic patients without diabetic retinopathy (80 patients, 160 eyes), with those of normal control group (21 persons, 42 eyes) and diabetic retinopathy patients (20 patients, 40 eyes). The correlation between flare values and the risk factors of diabetic retinopathy was evaluated in diabetic patients without diabetic retinopathy. RESULTS: Flare values were highest in diabetic retinopathy patients, and higher in diabetic patients without diabetic retinopathy than normal control group with statistical significance (p<0.01). Flare values were not significantly correlated with the risk factors of diabetic retinopathy. CONCLUSIONS: Microvascular injury appears to be developed in diabetic patients without diabetic retinopathy.
Aqueous Humor ; Diabetes Mellitus ; Diabetic Retinopathy ; Humans ; Risk Factors