Search

Abstract. Purpose: To establish the efficacy and safety of timolol maleate/dorzolamide fixed combination (TDFC) versus timolol maleate/pilocarpine fixed combination (TPFC), each given twice daily, in primary open-angle glaucoma or ocular hypertensive patients. Methods: In this prospective, multicentred, double-masked trial, 37 patients were treated twice daily with timolol for 4 weeks. They were then randomized to one of the treatment medications for 6 weeks, after which they were treated with timolol again for 2 weeks before being placed on the opposite treatment medication for 6 weeks. Results: A total of 36 patients completed the trial. Their mean baseline intraocular pressure (IOP) was 22.3 ± 3.7 mmHg. Following 6 weeks of treatment, the mean trough (08.00 hours) IOP was 18.0 ± 2.2 mmHg for TDFC and 17.4 ± 2.0 mmHg for TPFC (p = 0.22). The mean diurnal curve IOP was 18.1 ± 2.2 mmHg for TDFC and 16.7 ± 1.9 mmHg for TPFC (p = 0.0007). At the remaining time-points (10.00, 18.00 and 20.00 hours), TPFC IOPs were statistically lower than TDFC IOPs (p < 0.03). There were statistically more unsolicited reports of vision change and ocular pain associated with TPFC (p = 0.04). Six patients were discontinued early from TPFC therapy (17%) versus two from TDFC (6%) (p = 0.13). Conclusions: This study suggests that TPFC can provide at least a similar efficacious reduction in IOP as TDFC in patients with primary open-angle glaucoma or ocular hypertension. [ABSTRACT FROM AUTHOR]

Unlabelled: Spasm of blood vessels supplying the optic nerve head is considered one of possible ischaemic mechanisms of glaucomatous optic neuropathy., Purpose: The aim of the study was to evaluate the role of two potent and long-acting vasoconstrictors: endothelin-1 (ET-1) and neuropetide Y (NPY) in the pathogenesis of glaucoma by: 1) measurement of plasma ET-1 and NPY concentrations in primary open-angle glaucoma (POAG) patients with high intraocular pressure (HTG patients) and with normal intraocular pressure (NTG patients) at baseline and following peripheral exposure to cold (cold-pressor test), 2) assessment whether changes, if any, in the plasma concentrations of both peptides following the cold-pressor test correlate with visual field defects., Material and Methods: The study was conducted in three groups of subjects: 1) HTG patients, 2) NTG patients and 3) controls. All subjects were young and free from any cardiovascular disorders. ET-1 and NPY concentrations in the plasma were measured by radioimmunoassay (ET-1: Amersham International UK, NPY: Peninsula Laboratories INC). The cold-pressor test was performed by immersing the whole hand in ice-cold water (4 degrees C) for 2 minutes. Visual fields were examined using standard automated perimetry (Octopus 101, G-2 programme, normal strategy)., Results: In the NTG patients the mean baseline plasma ET-1 concentration was significantly lower and the mean baseline plasma NPY concentration significantly higher compared to controls. On the other hand, there were no statistically significant differences in the mean baseline peptide levels between the HTG patients and the control subjects. After the cold-pressor test the mean ET-1 concentrations considerably increased in the three groups. The highest increase was seen in the NTG group and it was statistically significant compared to the HTG group and controls. Following the cold-pressor test the mean NPY concentration was significantly decreased in the NTG group, but remained virtually unchanged in the HTG group and controls. In the NTG patients, significant increase in the mean ET-1 concentration and decrease in the mean NPY concentration seen after the cold-pressor test were accompanied by a significant decrease in the mean MS (mean retinal sensitivity) value in the second eye examined after the cold-pressor test, but no correlation was found between changes in the MS values and changes in the ET-1 and NPY concentrations. There were no significant changes in the mean MS values after cold-pressor test in the HTG patients and controls., Conclusions: Our findings suggest abnormal neuro-endothelial mechanisms of vascular tone control in NTG patients, related to the effects of ET-1 and NPY, secondary to endothelial dysfunction and to dysregulation of the autonomic nervous system. These abnormalities may involve potentiation of the vasoconstrictive effects of both ET-1 and NPY leading to the optic nerve head ischaemia and subsequent development of visual field defects in the course of normal-tension glaucoma.

Purpose: To establish the efficacy and safety of timolol 0.5%/dorzolamide 2% fixed combination versus timolol 0.5%/pilocarpine 2% fixed combination, each given twice daily, in primary open-angle glaucoma and ocular hypertensive patients., Material and Methods: In this prospective, multicenter, double-masked trial, 37 patients were treated twice daily with timolol for 4 weeks. Then, they were randomized to one of the treatment medications for 6 weeks, after which they were treated with timolol again for 2 weeks before placed on the opposite treatment medication for 6 weeks., Results: A total of 36 patients completed the trial. The mean baseline intraocular pressure (IOP) was 22.3 +/- 3.7 mmHg. Following 6 weeks of treatment, the mean decrease of IOP was 18.0 +/- 2.2 mmHg for timolol/dorzolamide combination and 17.4 +/- 2.0 for timolol/pilocarpine combination. The mean diurnal curve IOP was 18.1 +/- 2.2 mmHg for timolol/dorzolamide group and 16.7 +/- 1.9 mmHg for timolol/pilocarpine group. These differences were statistically significant. Statistically more patients reported ocular pain and diminished vision during use of the timolol/pilocarpine combination., Conclusions: This study suggest that timolol 0.5%/pilocarpine 2% fixed combination can provide at least similar efficacious reduction in IOP as timolol 0.5 %/dorzolamide 2% fixed combination in patients with primary open-angle glaucoma and ocular hypertension.