Effect of 1%brinzolamide and 0.5%timolol fixed combination on intraocular pressure after cataract surgery with phacoemulsification

AIM:To evaluate the effect of brinzolamide-timolol fixed combination on intraocular pressure(IOP)after cataract surgery.METHODS:The study included 92 eyes of 87 patients who underwent cataract surgery and intraocular lens implantation.Patients scheduled for phacoemulsification were assigned to 1 of 2 groups.The treatment group received 1 drop of brinzolamide-timolol fixed combination immediately after surgery,and the control group received no treatment.The IOP was measured preoperatively and at 2h and 24h postoperatively.RESULTS:The mean IOP change was lower in the treatment group than in the control group at 2h postoperatively.The difference between the mean IOP values of the two groups at 2h postoperatively was found to be statistically significant.Twenty-four hours after the surgery,the mean IOP change was still higher in the control group when compared to the treatment group.CONCLUSION:The fixed combination brinzolamidetimolol can effectively reduce IOP after cataract surgery.

Effects of brinzolamide on rabbit ocular blood flow in vivo and ex vivo

AIM：To investigate if significant improvement of optic disc blood flow（ODBF） occurs after instillation of brinzolamide onto rabbit eyes.METHODS：Testing of bilateral intraocular pressure（IOP） and left ODBF in 10 male rabbits took place every 3 h over a 24 h period.Brinzolamide（1% ophthalmic solution,two drops at 9：00 and 21：00） was administered to the left eye.ODBF,assessed using laser speckle flowgraphy,was determined as the mean blur rate（MBR）.Furthermore,the effect of brinzolamide on isolated rabbit ciliary arteries using isometric tension recording system was performed.RESULTS：After brinzolamide instillation,IOP was significantly decreased in the left eye.MBR-vessel was greater at 18：00 and 21：00（P〈0.05） than in the controls.MBRtissue and MBR-average were greater at 18：00（P〈0.05） than in the controls.For isolated arteries pre-contracted with a high-K solution,brinzolamide induced concentration-dependent relaxation,reaching 46.1%±9%（n=21） at 1 mmol/L.In Ca^2＋-free solutions,incubation with brinzolamide suppressed 1 μmol/L histamine-induced contractions（P〈0.05）.CONCLUSION：Brinzolamide decreases IOP and increases ocular blood flow.The direct vasodilatory effect of brizolamide is mediated by suppression of Ca^2＋ release from intracellular calcium stores.

Comparative Evaluation of the Efficacy of the Bimatoprost 0.03%, Brimonidine 0.2%, Brinzolamide 1%, Dorzolamide 2%, and Travoprost 0.004%/Timolol 0.5%-Fixed Combinations in Patients Affected by Open-Angle Glaucoma

Purpose: This is a retrospective, comparative, head-to-head, not commissioned study about the efficacy of bimato-prost 0.03%, brimonidine 0.2%, brinzolamide 1%, dorzolamide 2%, and travoprost 0.004%/timolol 0.5%-fixed combinations in patients affected by na?ve open-angle glaucoma and IOP > 25 mmHg. Patients and Methods: Files from 70 patients (35 M, 35 F, mean age 69.52 y, S.D. 11.56, range: 37-87y) in our Glaucoma Service were retrospectively analyzed as long as 12 months. Every subgroup, including 14 age- and sex-matched patients, was allocated to 1 of the 5 groups of the fixed combinations monotherapy. Data recorded after 3 months follow-up were statistically analyzed by descriptive and ANOVA statistics as percentage of IOP reduction from baseline. Results: All the fixed combinations were effective in lowering IOP. The mean percentage reduction was: brimonidine/timolol 43.57%, dorzolamide/timolol 37.67%, bimatoprost/timolol 35.60%, travoprost/timolol 33.25% and brinzolamide/timolol 23.0%. The brimonidine/timolol fixed combination showed to be statistically significant more effective only than brinzolamide/timolol fixed combination (p = 0.001). Setting the α error to 5%, the power of the study is 26%, phi: 0.842. Discussion: In all this cohort of patients the target IOP was successfully achieved. All the fixed combinations used in this study had a very good profile of efficacy. Brimonidine, dorzolamide, bimatoprost and travoprost/timolol fixed combinations statistically significantly reduced the percentage of IOP from baseline (p = 0.001) more than brinzolamide/timolol fixed combination.

Intraocular pressure with rebound tonometry and effects of topical intraocular pressure reducing medications in guinea pigs

AIM： To investigate the intraocular pressure（IOP） of adult guinea pig eyes with rebound tonometry（RBT）,and assess the effects of four distinctive topical IOP reducing medications including Carteolol,Brimonidine,Brinzolamide and Latanoprost.METHODS： The IOPs of twenty-four 12-week-old guinea pigs（48 eyes） were measured every two hours in one day with RBT as baselines.All the animals were then divided into four groups（Carteolol,Brimonidine,Brinzolamide and Latanaprost groups,n=6）.The IOPs were measured and compared to the baseline 1,2,3,5,7,9,15 and 24 h after treatment.RESULTS： The mean baseline IOP of 24 guinea pigs（48 eyes） was 10.3±0.36 mm Hg（6-13 mm Hg） and no binocular significant differences of IOPs were observed（t=1.76,P〉0.05）.No significant difference of IOP in Carteolol group at each time point was observed before and after treatment（t=1.48,P〉0.05）.In Brimonidine group,IOP was 2.2±1.9 mm Hg lower than the baseline after one hour（t=3.856,P=0.003） and lasted for one hour.In Brinzolamide group,IOP was 1.4±1.1 mm Hg lower than the baseline after one hour（t=4.53,P=0.001） and lasted for 7h and the IOP declined most at 3h.In Latanaprost group,IOP was 2.1±1.3 mm Hg lower than the baseline after one hour（t=6.11,P=0.001） and lasted for one hour.CONCLUSION： The IOP of guinea pig eyes is relatively stable compared to human eyes.In four reducing IOP medications,no significant effect of Carteolol is observed.Brinzolamide has the longest duration,while the Brimonidine has the shortest duration and the maximum level of treatment.