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

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

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

PURPOSE: We evaluated the efficacy of the PCR which is known as more sensitive method than culture in the diagnosis of causal microorganisms of the infective endophthalmitis. METHODS: We used 0.3 ml of aqueous humor and 0.5 ml of vitreous sample in 3 cases of postoperative and 1 case of endogenous endophthalmitis for detecting causal microorganisms. To detect the bacteria we used universal, Gram positive and negative primers, and to detect the fungus we used fungal primer. RESULTS: Three cases of endophthalmitis, there was no bacteria in the bacterial culture for 10 days but PCR results identified causal microorganisms in all cases. CONCLUSIONS: PCR is effective in the fast and accurate diagnosis of infective endophthalmitis and especially in the culture-negative endophthalmitis.
Aqueous Humor ; Bacteria ; Diagnosis* ; Endophthalmitis* ; Fungi ; Polymerase Chain Reaction*

To evaluate the effects of mitomycin C(MMC) on the fibrous capsule of the anterior chamber tube shunt to a surgical membrane(ACTSSM) surgery, 0.04% MMC solution was applied on the episclera for 5 minutes before ACTSSM surgery(group A, 9 rabbits). At postoperative 2, 4 and 8 weeks, 6 eyes of the 3 rabbits from each group were enucleated and light microscopic examinations of the fibrous capsules were done. In group A, fibrous capsules had many microcystic spaces and fibrous tissues between twofold surgical membranes were scanty. But in control group(group B, 9 rabbits), fibrous capsules showed higher density of fibroblast and less microcystic spaces than group A, suggesting low permeability of the fibrous capsule to aqueous humor. These results suggest that MMC may increase the success rate of the ACTSSM surgery.
Anterior Chamber* ; Aqueous Humor ; Capsules ; Fibroblasts ; Membranes* ; Mitomycin* ; Permeability ; Rabbits*

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