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Background: To compare the efficacy and tolerance of three prostaglandin analogues, bimatoprost, latanoprost and travoprost in patients with previously untreated open-angle glaucoma and ocular hypertension. Methods: Prospective randomized single (investigator) masked comparative clinical trial at the Taunton and Somerset NHS Hospital, Taunton, UK. Newly diagnosed, treatment naive glaucoma/ocular hypertension patients were recruited. Patients were randomized into three groups to receive one of the three prostaglandin analogues. Intraocular pressure (IOP) was measured before starting treatment and after 2 and 6 months of treatment. The IOP reduction and the tolerance profile of each drug were compared. The data were analysed on the basis of intention to treat, using analysis of covariance comparing IOP in the three groups at 2 and 6 months, adjusting for baseline IOP. Tolerance levels were compared using Kruskal–Wallis test. Results: Of the 122 patients, 40 patients were given bimatoprost, 42 received latanoprost and 40 had travoprost. At 2 months, there was a significant difference between the three treatment groups (P = 0.013) with bimatoprost achieving a greater reduction in IOP than the other two drops. However, at 6 months, the difference was not statistically significant (P = 0.13). There was no significant difference in the tolerance profile. Conclusion: All the three topical prostaglandin analogues are effective at lowering IOP, but bimatoprost was found to be most effective in the initial phase of the trial, and there was no statistically significant difference in the efficacy, among the three prostaglandin analogue eye drops after 6 months of treatment.

After successful trabeculectomy patients often complain of reduction in vision even after several months. Amongst other factors, corneal astigmatism appears to be altered. A pilot study measuring, pre- and post-operative corneal topography indicated three types of astigmatic change: some patients develop a relative superior corneal steepening, others a superior flattening and yet others complex regional changes that do not conform to either of these patterns. The present study was designed to evaluate further these patterns of variation in corneal curvature and to look for corresponding refractive and keratometry changes. Twenty-nine patients admitted for trabeculectomy had pre-operative assessment of subjective and automated refraction, manual keratometry and corneal topography from which simulated keratometry values were calculated. A standard trabeculectomy procedure was performed and post-operative measurements of the same parameters were taken at 1 and 3 months after surgery. Similar patterns of corneal topographic change to those found in our pilot study were noted. In both the superior steepening and superior flattening groups there was an increase in vertical keratometry and a shift towards 'with-the-rule' astigmatism. Furthermore a 1 year analysis of 13 patients from our pilot study indicated that the topographic changes lasted for at least 12 months after surgery. We conclude that computer-assisted corneal topography reveals complex regional changes in corneal curvature that are not readily detected from alterations in refraction or keratometry. These changes are sufficiently great to have a significant effect on visual function in some patients.

To compare the efficacy and tolerance of three prostaglandin analogues, bimatoprost, latanoprost and travoprost in patients with previously untreated open-angle glaucoma and ocular hypertension.Prospective randomized single (investigator) masked comparative clinical trial at the Taunton and Somerset NHS Hospital, Taunton, UK. Newly diagnosed, treatment naïve glaucoma/ocular hypertension patients were recruited. Patients were randomized into three groups to receive one of the three prostaglandin analogues. Intraocular pressure (IOP) was measured before starting treatment and after 2 and 6 months of treatment. The IOP reduction and the tolerance profile of each drug were compared. The data were analysed on the basis of intention to treat, using analysis of covariance comparing IOP in the three groups at 2 and 6 months, adjusting for baseline IOP. Tolerance levels were compared using Kruskal-Wallis test.Of the 122 patients, 40 patients were given bimatoprost, 42 received latanoprost and 40 had travoprost. At 2 months, there was a significant difference between the three treatment groups (P = 0.013) with bimatoprost achieving a greater reduction in IOP than the other two drops. However, at 6 months, the difference was not statistically significant (P = 0.13). There was no significant difference in the tolerance profile.All the three topical prostaglandin analogues are effective at lowering IOP, but bimatoprost was found to be most effective in the initial phase of the trial, and there was no statistically significant difference in the efficacy, among the three prostaglandin analogue eye drops after 6 months of treatment.

Purpose: To assess the effects of central corneal thickness (CCT) and corneal curvature (CC) on the measurements of intraocular pressure (IOP) using Goldmann applanation tonometer (GAT) and the ocular blood flow pneumatonometer (OBFT). Methods: 104 patients were recruited from a glaucoma clinic. The CCT was measured using ultrasound pachymetry and the mean radius of CC using a keratometer. The IOP of each eye was measured using both GAT and the OBFT in a random order. Right eyes only were analysed for statistical purposes. Results: The mean (±SD) IOP by GAT and OBFT was 18.2 mmHg (±4.4) and 18.2 mmHg (±4.0), respectively, with no statistically significant difference. IOP measurement with both instruments varied with CCT and CC. GAT showed an IOP increase of 0.40 mmHg per 10 µm increase of CCT and OBFT showed an increase of 0.38 mmHg in IOP per 10 µm increase of CCT. Multiple regression analysis showed that the effect of CCT was statistically significant (P

Ocular blood flow, in particular to the optic nerve head, is considered important in determining the extent of glaucomatous damage. The 24-hour variation in the pulsatile component of ocular blood flow (POBF) was measured using a pneumotonometer linked to the Langham Ocular Blood Flow System ® . Intraocular pressure (IOP), ocular pulse amplitude, POBF, systemic blood pressure and heart rate were recorded at three-hourly intervals over a 24-hour period in 10 ocular hypertensives, eight patients with primary open angle glaucoma (POAG) treated with timolol eyedrops (G timolol 0.25%), and eight ocular normotensive control subjects. The POAG subjects were readmitted for a second set of 24-hour measurements after temporarily discontinuing G timolol for two weeks. The POBF showed no significant diurnal variation in any of the patient groups, the POAG values being taken from the “off treatment” period. By contrast, there were overnight falls in IOP, ocular pulse amplitude, blood pressure and heart rate, which reached significance in some groups. This suggests that overall there are compensatory changes in IOP, blood pressure, heart rate, and perhaps ocular vascular resistance, to preserve POBF overnight. Within all groups there was much individual variation, with some subjects showing an overnight fall in POBF, suggesting a lack of autoregulation in these cases who might prove to be at greater risk of developing nocturnal glaucomatous damage. When timolol was withdrawn from POAG subjects, there was no change in POBF despite an increase in IOP, implying that timolol, though effective as ocular hypotensive, did not alter POBF.