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At least 937 records · Page 52Linked to original sources
PubMed1992

[Effect of argon laser trabeculoplasty on unrestricted outflow of aqueous humor in eyes with simple glaucoma].

In this prospective study we used the oculopressions-tonometry (OPT) for determination of the aqueous humor outflow facility (C). 53 phacic eyes with glaucoma simplex were examined pre- and postoperatively. One hour after operation C decreased from 0.15 to 0.14. In correlation to this fact the IOD increased. After 7 days C was higher already than preoperatively, 30 days and 6 months after operation C showed normal values. After 6 months the mean decrease in IOD was 5.8 mm Hg, the mean increase in C was 39%. The rate of success after 30 days was 77.4%. IOP and C showed statistically significant changes. The problems with determining C and the causes of the fluctuation of C during our follow-up are discussed.

Adult↗
PubMed1976

Determination of the facility of aqueous humor outflow in the dog, comparing in vivo and in vitro tonographic and constant pressure perfusion techniques.

The gross facility of aqueous humor outflow (C) was estimated in the normal in vivo and in vitro dog eye, using tonography and constant pressure perfusion. Tonographic C value for 36 normal eyes, with the dog anesthetized with ketamine hydrochloride and acetylpromazine maleate, was 0.21 (+/- 0.14, SD); the mean tonographic value in 35 eyes with the patient anesthetized with sodium pentobarbital was 0.15 (+/- 0.09). Constant pressure perfusion of the in vivo normal dog eyes at 20 mm of Hg intraocular pressure yielded a mean C value of 0.13 (+/- 0.07) and at 30 mm of Hg 0.18 (+/- 0.13). As intraocular pressure increased from 10 to 50 mm of Hg, the rate of outflow, as determined by constant pressure perfusion, increased. The C values from in vitro constant pressure perfusion were greater than those in the in vivo eyes and deceased in most eyes as intraocular pressure was increased as compared with the in vivo preparation.

Acepromazine↗
PubMed1982

The pressure dependency of aqueous humor formation in the anesthetized cat.

In cats anesthetized with pentobarbital Na, a highly significant correlation was found between the rate of aqueous humor production and eye arterial perfusion pressure (blood pressure minus intraocular pressure). The filtration coefficient for water was 0.312 microliter min-1 mm Hg-1. This value is not significantly different from those reported earlier for enucleated, arterially perfused eyes of the same species.

Animals↗
PubMed1986

Leukotrienes in the aqueous humor of patients with uveitis.

Utilizing chromatographic and radioimmunoassay techniques, we measured the concentration of leukotriene (LT) B4 and LTC4/D4/E4 in the aqueous humor of 14 patients with uveitis and seven patients undergoing penetrating keratoplasty or routine cataract extraction. Leukotriene B4 was detected in 11 of 14 patients with uveitis (mean, 0.96 pmole/mL), and LTC4/D4/E4 was found in 12 of 14 patients with uveitis (mean, 2.0 pmole/mL). In the control group, LTB4 was detected in six of seven patients (mean, 0.57 pmole/mL), and LTC4/D4/E4 was found in six of seven patients (mean, 1.9 pmole/mL). Leukotriene levels did not correlate with clinically assessed aqueous cell and flare. Mean levels of LT in patients with uveitis receiving corticosteroids were nearly double those found in non-steroid-treated patients. Despite apparent differences in LT levels, none of the above differences reached statistical significance.

Adrenal Cortex Hormones↗
PubMedDate not supplied

Photoreceptor outer segments in aqueous humor: key to understanding a new syndrome.

Retinal detachment with oral dialyses and tears of the nonpigmented epithelium of the ciliary body sometimes accompanies aqueous cells and high intraocular pressure with its marked fluctuation. The aqueous cells consist predominantly of photoreceptor outer segments which obstruct aqueous outflow at the trabecular meshwork and induce high intraocular pressure as ghost cells do in ghost cell glaucoma. A new clinical entity with the combination of these signs, namely, rhegmatogenous retinal detachment with "photoreceptor outer segment glaucoma" is designated as Schwartz-Matsuo syndrome in this report. The detection of photoreceptor outer segments in the anterior chamber indicates that a communication between subretinal space and aqueous humor has been established by some mechanism. The new syndrome should be included in differential diagnoses of iritis and glaucoma.

Aqueous Humor↗
PubMed1986

Penetration of ciprofloxacin into aqueous humor.

Ciprofloxacin is a potentially useful antibiotic in eye infection. A pilot study was performed on 25 patients undergoing routine cataract surgery to assess the penetration of the drug into aqueous humor after oral administration. The mean peak level of 0.56 mg/l achieved in aqueous is above the MIC for most gram negative organisms, including Pseudomonas aeruginosa.

Administration, Oral↗
PubMed1991

The nocturnal suppression of aqueous humor flow in humans is not blocked by bright light.

Normal human subjects were studied hourly by fluorophotometry to measure the normal circadian rhythm of aqueous humor flow. On a separate day, the subjects slept for approximately 1 hr after lunch; this short nap was not found to have any effect on aqueous flow. On a separate night, the subjects slept under a bright light of 2500 lux; the light was not found to have any effect on flow in the sleeping subjects. Because bright light blocks melatonin release in humans, nocturnal suppression of aqueous flow in humans may not be driven by systemic melatonin release.

Aqueous Humor↗
PubMed1987

Topical vs systemic gentamicin penetration into the human cornea and aqueous humor.

Twenty-two patients undergoing penetrating keratoplasty received either topical fortified gentamicin (13.6 mg/mL) or a loading dose of intramuscular gentamicin before surgery. Cornea and aqueous humor samples were obtained and assayed by radioimmunoassay for gentamicin. In the topical group, the average gentamicin levels in the cornea and aqueous were 16.2 micrograms/g and 0.3 microgram/mL, respectively. Parenteral drug levels were less variable and averaged 6.1 micrograms/g in the cornea and 0.4 microgram/mL in the aqueous. Although this study demonstrates that parenteral therapy can be used to deliver adequate drug levels to the cornea, it requires far more antibiotic and subjects the patient to potentially toxic systemic side effects. Therefore, topical administration is the preferred route of delivery of antibiotic to the cornea.

Administration, Topical↗
PubMed1989

Aqueous humor concentration of metoprolol after oral administration.

The concentration of the beta-adrenergic blocking agent metoprolol was determined in the blood plasma and aqueous humor after oral administration of the compound. One group (10 cases) was receiving their prescribed continuous therapy and the other group (20 cases) received a single dose of metoprolol. The concentration of metoprolol was usually higher in aqueous than in plasma after continuous administration. This differs significantly from administration of a single dose where the concentration of metoprolol was higher in plasma. The result indicates an ocular accumulation of the drug in chronic systemic treatment.

Administration, Oral↗
PubMed1975

Aqueous humor pH changes after experimental alkali burns.

Following application of 2N sodium hydroxide, or 8.1N ammonium hydroxide to rabbit cornea, the aqueous humor pH reached a maximum of 10.2, 11.9, and 12 within six minutes following 20-, 50-, and 100-mu1 sodium hydroxide burns, respectively; after two hours the pH had fallen to 8.5, 10, and 10.5. The maximum rise following application of 100-mu1 of ammonium hydroxide was 10.8, declining to about 9 at two hours. The fall in pH following a 100-mu1 sodium hydroxide burn was not greatly influence by external lavage. However, the pH was significantly lowered (12 to 10) by paracentesis alone and further reduced by immediate or delayed intracameral administration of phosphate buffer. On the basis of these results moderately severe and severe alkali burns of the eye should be treated by paracentesis and if possible with anterior chamber reformation with a sterile solution.

Alkalies↗
PubMed1999

Acute versus chronic effects of brimonidine on aqueous humor dynamics in ocular hypertensive patients.

PURPOSE: To report the acute vs chronic effects of brimonidine, a selective alpha2-adrenergic receptor agonist, on aqueous humor dynamics in ocular hypertensive patients. METHODS: Brimonidine 0.2% was given topically twice daily for 29 days to one eye each of 28 ocular hypertensive volunteers in a randomized double-masked study. The fellow eye was similarly treated with vehicle. Aqueous flow (Fa) and outflow facility (Cfl) were determined with fluorophotometry. Intraocular pressure, outflow facility (Cton), and episcleral venous pressure (Pev) were measured with pneumatonometry, tonography, and venomanometry, respectively. Uveoscleral outflow (Fu) was calculated from intraocular pressure, Fa, Pev, and Cfl values. All measurements were taken on baseline day, day 8, and day 29 of treatment. Intraocular pressure and Fa only were measured after instillation of 1 drop of brimonidine on day 1. RESULTS: When measured 3 hours after instillation on days 1, 8, and 29 of treatment, brimonidine significantly (P < .001) reduced intraocular pressure by at least 5.0 +/- 0.7 mm Hg (mean +/- SEM) compared with baseline day, and by 2.7 +/- 0.5 mm Hg compared with the vehicle-treated contralateral control eyes. The greatest decrease (6.0 +/- 0.6 mm Hg) was observed at 3 hours after the first drop. Aqueous flow was reduced by 29% (P < .001) after the first application but was not significantly different from baseline when measured at day 29 of treatment. Uveoscleral outflow was increased 60% at day 8 (P < .06) and day 29 (P < .05) compared with baseline. There was no significant difference in outflow facility or episcleral venous pressure at day 8 or day 29 of treatment. CONCLUSIONS: The brimonidine-induced reduction in intraocular pressure in humans is associated initially with a decrease in aqueous flow, and after chronic treatment with an increase in uveoscleral outflow.

Adrenergic alpha-Agonists↗
PubMed2026

Glaucoma filtering surgery combined with phacoemulsification in the era of new aqueous humor filtration devices: A systematic review.

We evaluate the efficacy and safety of filtering glaucoma surgeries combined with phacoemulsification (PCE)-including new aqueous humor drainage devices-compared to standalone procedures. We performed a systematic search up to March 23, 2025, including all comparative studies assessing trabeculectomy (TRAB), non-penetrating deep sclerectomy (NPDS), Xen&#xae; Gel Stent (XEN), or Preserflo&#xae; MicroShunt (PMS) combined with PCE, versus the same surgery alone. Key exclusion criteria include inadequate follow-up (less than 12-month), absence of a defined success criterion, more than 50% of loss to follow-up at 12-month, and lens extraction performed without PCE. Main outcome was surgical success at &#x2265;&#x202f;12 months. Secondary outcomes included intraocular pressure (IOP) reduction, decrease in hypotensive medications, and rates of complications. A total of 27 studies were included for analysis. Among studies comparing TRAB/PCE with standalone TRAB, half reported similar success rates, while others favored standalone TRAB, particularly using strict IOP thresholds. Safety profiles were comparable. For NPDS/PCE, data mostly showed equivalent outcomes versus standalone NPDS, with comparable safety. In studies on XEN/PCE and PMS/PCE, results suggested similar rates of surgical success, efficacy in IOP and medication reduction, and safety compared to their stand-alone procedures. Small differences occasionally favored standalone procedures under stricter success definitions. Current evidence suggests that combined filtering glaucoma surgery provides long-term efficacy and safety comparable to standalone, though some subgroups and outcome thresholds may slightly favor standalone approaches. The limited availability of high-quality prospective trials underscores the need for further large-scale robust studies.

Humans↗
PubMed2006

Cytokine profile in aqueous humor and sera of patients with infectious or noninfectious uveitis.

PURPOSE: To determine the cytokine expression profile at the protein level in aqueous humor (AqH) and sera of patients with uveitis. METHODS: Patients with various clinical entities of strictly diagnosed infectious or noninfectious uveitis were tested. AqH and sera were collected from patients with uveitis. AqH was also collected during surgery from patients with cataract, as control specimens. Interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-2, -4, -5, and -10 were measured from nondiluted samples simultaneously, with microparticle-based flow cytometric analysis. RESULTS: In AqH IFN-gamma was the most abundant cytokine in both infectious (mean, 3240.5 pg/mL) and noninfectious (mean, 115.6 pg/mL) uveitis, and IL-10 was the second (mean, 402.1 pg/mL, infectious uveitis; 7.5 pg/mL, noninfectious uveitis). The expression level of other cytokines in AqH was generally higher in infectious uveitis than in noninfectious uveitis, but the levels were lower than that of IL-10. There was no remarkable difference, however, in the cytokine expression pattern in AqH of the different clinical entities of uveitis. Sera from patients with noninfectious uveitis contained IFN-gamma (mean, 45.0 pg/mL), but the other serum cytokines in both types of uveitis were low or under the detectable level. CONCLUSIONS: IFN-gamma is the most abundant cytokine in infectious and noninfectious uveitis, with a remarkable difference between the two groups. The data suggest that cytokines in AqH of infectious uveitis are locally produced, whereas in noninfectious uveitis, IFN-gamma is produced both in the eye and the peripheral blood.

Adult↗
PubMed1986

High concentrations of enolase, alpha- and gamma-subunits, in the aqueous humor in cases of retinoblastoma.

Because retinoblastomas contain a large amount of the gamma-subunit of enolase or neuronspecific enolase, we studied the aqueous humor levels of the gamma-subunit and alpha-subunit in 12 cases of retinoblastoma. Enzyme immunoassay demonstrated that both the gamma-subunit and the alpha-subunit were greatly increased in all 12 (minimum levels, 87.8 ng/ml and 354 ng/ml, respectively). Thus, aqueous enolase levels, especially that of the gamma-subunit, are useful in the diagnosis of retinoblastoma and may be useful as monitoring markers in retinoblastoma involving the central nervous system.

Aged↗