The influence of Latanoprost 0.005% on aqueous humor flow and outflow facility in glaucoma patients: a double-masked placebo-controlled clinical study.

BACKGROUND: Fluorophotometry and pneumotonography were performed to investigate the effect of Latanoprost 0.005% and Placebo on aqueous humor flow and total outflow facility in human glaucomatous eyes. METHODS: In a randomized double-blind clinical study patients with POAG and OHT receive either Latanoprost 0.005% or placebo once in the evening. Fluorophotometry (Fluorotron Master II, Ocumetrics) and, Pneumotonography, Mentor) was performed in 20 eyes of 10 patients (verum) and 22 eyes of 11 patients (placebo). During a 2 week wash-out period all patients received a systemic antiglaucomatous therapy (Acetazolamide) up to 3 days before baseline measurement. Patients with IOP higher than 28 mmHg at baseline were excluded. Fluorophotometry, tonography and IOP were measured at baseline after 1 and 2 weeks of treatment. Data was analysed by the Student's paired t test. RESULTS: All patients completed the protocol. The IOP significantly decreased (25%) after 1 and 2 weeks of treatment with Latanoprost(p<0.01). Fluorophotometry measurements showed no difference in flow over time in both groups. Although tonographic mean C values in both groups did not show any difference over time, the estimated total outflow facility C (Goldmann) increased significantly (p<0.05) in the verum-treated eyes after 2 weeks. A significant difference of outflow co-efficient correlated to normal pressure (P0/C) was found after 2 weeks of treatment with Latanoprost (p<0.05). CONCLUSIONS: In accordance with the literature we found a mean 25% decrease in IOP after 2 weeks of treatment with Latanoprost 0.005%. The analysis of the flow values in both groups showed no increase or decrease in aqueous humor dynamics as proved in many previous studies. The known effect of Latanoprost increase uveoscleral outflow by remodeling extracellular matrix and widening intermuscular spaces in the ciliary body may not detected by pneumotonography after 2 weeks of treatment. The significant increase in estimated total outflow facility (Goldmann formula) in latanoprost-treated eyes and the decrease of IOP took place at constant flow rates. The increase in conventional outflow facility may indicate trabecular meshwork changes, but it cannot explain the significant decrease in IOP. Furthermore, an additional effect, e.g. uveoscleral outflow, may play the major role as considered in many previous studies.

Knowledge about glaucoma in the unselected population: a German survey.

PURPOSE: To determine the general population's knowledge about glaucoma. MATERIALS AND METHODS: A representative survey of the German population was conducted in which 2,742 men and women were interviewed face to face. The sample was matched with the German population for age, sex, education, income, and other factors. Questions were asked concerning the nature, occurrence, possible risk factors, and course of glaucoma. RESULTS: Fifty-one percent of the population had an active knowledge of the term "glaucoma" and 75% had a passive knowledge of the term. Of those interviewees with a passive knowledge, glaucoma was thought to be associated with raised intraocular pressure (IOP) by 28% and loss of visual field (14%) but also with corneal (14%) or lens disease (10%). Only 8.4% correctly recognized a basic glaucoma definition. Suspected symptoms were blurred vision (39%), pain (28%), or reading difficulties (22%). Twenty-nine percent of respondents believed that one is able to feel increased IOP. Prevention of visual loss was believed to be possible by reading (16%) or smoking less (11%). Therapeutic measures known were surgery (63%), laser treatment (26%), and medical treatment (23%). Information about glaucoma was mainly obtained from friends (44%), and less often from doctors (13%). CONCLUSIONS: In a large representative sample of the population, knowledge about glaucoma, its signs and symptoms, risk factors, treatment, and possible outcome is poor. Lack of knowledge in the general population may be an important cause for failure to detect glaucoma and may result in blindness from the disease.