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

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

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

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*

The fibrovascular tissues surrounding a glaucoma implant have been found to play a major role for the orbital absorption of aqueous humor following a glaucoma implant surgery. An ultrasonographic study was performed to investigate the ultrasonographic, characteristics of the tissues and its relationship with the postoperative intraocular pressure(IOP) control. Twenty-three eyes of 23 patients had undergone the e-PTFE membrane-silicone tube implantation and had been followed up for at least 6-month(mean +/- SD, 17 +/- 8.8 months). An ultrasonographic study for these eyes included such paramneters as presence of an aqueous reservoir surrounding the implant, size(height) of the aqueous reservoir and echoreHectivity from the reservoir wall tissues. The aqueous reservoir was identified in 22(96%) of 23 eyes and had a height varying from 1.0 mm to 5.5 mm. In eyes with an aqueons reservoir. 3 mm high or more, the IOPs were all 21 mmHg or less without further glaucoma medications(p=0.040, chi-square). In one eye with an obliterated reservoir on ultrasonography, the opening of the silicone tube was found to be occluded toward the extrascleral portion of the implant when reoperation was performed. The echo reflections from reservoir wall tissues were denser and higher comparing with those from the sclera of the respective eye in 7 eyes with a complete failure of postoperative lOP control(>or=30 mmHg on maximum medical theraph). These eyes also had and irregular echoreflections within the aqueous reservoir, which reflect an invasion of proliferating tissues into the reservoir.
Absorption ; Aqueous Humor ; Glaucoma* ; Humans ; Orbit ; Reoperation ; Sclera ; Silicones ; Ultrasonography

Cyclodialysis and ciliochoroidal detachment was performed in one eye of three rabbits and in one eye of another three rabbits respectively. 0.1 ml of 10% sodium fluorescein was injected intracamerally after aspiration of aqueous humor and the eyeball was enucleated between 30 minutes and one hour after sodium fluorescein injection and prepared for fluorescence microscopy. Sodium fluorescein concentration in supraciliary space was much greater in group with cyclodialysis or ciliochoroidal detachment than in normal control group. These results suggest that in the eye with cyclodialysis, aqueous humor may gain access freely to supraciliary space through the cleft between anterior chamber and supraciliary space and then is removed rapidly and in the eye with ciliochoroidal detachment, aqueous humor may pass through uveoscleral outflow pathway.
Anterior Chamber ; Aqueous Humor* ; Fluorescein ; Microscopy, Fluorescence ; Rabbits

PURPOSE: We evaluated ocular penetration and drug level in tear after topical ofloxacin instillation in rabbit eye with amniotic membrane transplantation(AMT). METHODS: In the first set of experiment, 24 rabbits(24 eyes) were divided into 4 groups according to the epithelial removal or AMT. Topical ofloxacin was instilled 4 times every 15 minutes and then, 1 hour after the last eyedrop, the samples of amniotic membrane(AM), cornea and aqueous humor were collected. In the second set of experiment, 24 rabbits(24 eyes) were divided into 6 groups according to the freshness of AM or its attached time. Topical ofloxacin was applied to eyes and then, tear samples were collected at 30 minutes, 1, 2, 4, and 6 hours. Ofloxacin concentration in the samples of two experiments were evaluated using high performance liquid chromatography. RESULTS: Mean ofloxacin concentrations in cornea and aqueous humor were statistically higher in deepithelized corneas regardless of AMT(P<0.05). And mean tear levels of ofloxacin in AMT groups were statistically higher than those in non-AMT groups(P<0.05). CONCLUSIONS: AMT seems to interfere with the ocular penetration of topical ofloxacin in normal rabbit cornea, but rather enhances ofloxacin penetration in the cornea with epithelial defect. And also the ofloxacin level in tear was higher in eyes with AMT up to 1 hour after topical ofloxacin use. Therefore it seems that AM has potential to act as an effective drug delivery system.
Amnion* ; Aqueous Humor ; Chromatography, Liquid ; Cornea ; Drug Delivery Systems ; Ofloxacin*