title: Changes in intraocular pressure and ocular perfusion pressure after latanoprost 0.005% or brimonidine tartrate 0.2% in normal-tension glaucoma patients.
abstract: OBJECTIVE
  To evaluate and compare the effects of latanoprost 0.005% once daily and brimonidine tartrate 0.2% twice daily in patients with normal-tension glaucoma (NTG).
  
  
  METHODS
  A randomized, open-label, crossover study.
  
  
  METHODS
  Twenty-eight NTG patients with progressive visual field defects/optic disc excavation, new disc hemorrhage, or field defects that threatened fixation.
  
  
  METHODS
  Patients were randomly allocated to one of two groups. Patients in group 1 were treated with latanoprost, lubricant, and brimonidine for 4 weeks each, whereas patients in group 2 were treated with brimonidine, lubricant, and latanoprost for 4 weeks each.
  
  
  METHODS
  Intraocular pressure (IOP), pulse rate, and blood pressure were measured at 8 am, 12 noon, and 4 pm after each 4-week treatment. Ocular perfusion pressure (OPP) was calculated.
  
  
  RESULTS
  Latanoprost and brimonidine reduced the average IOP by 3.6 +/- 1.9 mmHg (P < 0.001) and 2.5 +/- 1.3 mmHg (P < 0.001), respectively, with a significant difference between the two regimens (P = 0.009). Both drugs significantly reduced IOP at each time point. Latanoprost decreased IOP significantly more than did brimonidine at 8 am (11.7 +/- 2.2 mmHg vs. 13.7 +/- 2.1 mmHg, P = 0.004) and 4 pm (11.4 +/- 2.1 mmHg vs. 13.2 +/- 2.9 mmHg, P = 0.004), but IOP was equal between the two agents at 12 noon (11.5 +/- 2.6 mmHg vs. 11.5 +/- 2.3 mmHg, P = 0.967). IOP was maintained at 12 mmHg or lower in 18 (66.7%) of 27 patients after treatment with latanoprost and in 9 (33.3%) of 27 patients after treatment with brimonidine. Latanoprost monotherapy reduced IOP by 30% in 8 patients (29.6%), but brimonidine monotherapy did not reduce IOP by that much in any of the patients. OPP increased after latanoprost treatment (P < 0.001) but did not increase after brimonidine treatment (P = 0.355). There was no significant change in pulse rate or blood pressure.
  
  
  CONCLUSIONS
  Both latanoprost and brimonidine reduce IOP in NTG patients. Brimonidine has a peak IOP-lowering effect equal to that of latanoprost but produces a higher mean diurnal IOP than does latanoprost because of its shorter effect. Latanoprost might favorably alter optic disc blood perfusion by increasing OPP.
authors.affiliation: Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Catherine Jui-Ling
authors.initials: CJ
authors.lastname: Liu
authors.forename: Yu-Chieh
authors.initials: YC
authors.lastname: Ko
authors.forename: Ching-Yu
authors.initials: CY
authors.lastname: Cheng
authors.forename: Allen W
authors.initials: AW
authors.lastname: Chiu
authors.forename: Joe C
authors.initials: JC
authors.lastname: Chou
authors.forename: Wen-Ming
authors.initials: WM
authors.lastname: Hsu
authors.forename: Jorn-Hon
authors.initials: JH
authors.lastname: Liu
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D000068438:Brimonidine Tartrate; D018592:Cross-Over Studies; D004341:Drug Evaluation; D005123:Eye / Q000098:blood supply*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000188:drug therapy* / Q000503:physiopathology; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects*; D000077338:Latanoprost; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000187:drug effects / Q000503:physiopathology; D009901:Optic Nerve Diseases / Q000188:drug therapy / Q000503:physiopathology; D011461:Prostaglandins F, Synthetic / Q000008:administration & dosage / Q000627:therapeutic use*; D011810:Quinoxalines / Q000008:administration & dosage / Q000627:therapeutic use*; D014786:Vision Disorders / Q000188:drug therapy / Q000503:physiopathology; D014794:Visual Fields / Q000187:drug effects
chemical_list: D000316:Adrenergic alpha-Agonists; D000959:Antihypertensive Agents; D011461:Prostaglandins F, Synthetic; D011810:Quinoxalines; D000068438:Brimonidine Tartrate; D000077338:Latanoprost