title: Contralateral intraocular pressure lowering effect of prostaglandin analogues.
abstract: BACKGROUND
  Though the use of prostaglandin analogues (PGA) for reduction of intraocular pressure (IOP) has shown a marked increase, studies evaluating the contralateral effects of PGA are limited.
  
  
  OBJECTIVE
  To evaluate if PGA treatment in one eye has an effect on the IOP of the untreated fellow eye.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Thirty patients of open-angle glaucoma with no previous antiglaucoma treatment underwent 24-hour diurnal IOP phasing. They subsequently were started on a uniocular trial with PGA, and had office diurnal IOP measurements 6 weeks later. Twenty-four hour diurnal consisted of 8 IOP readings over 24 hours and office diurnal consisted of 4 IOP readings between 8 AM and 6 PM at 3 hourly intervals.
  
  
  METHODS
  IOPs of the fellow eye during the office diurnal were compared with IOPs at similar time points during the 24-hour diurnal using paired t-tests.
  
  
  RESULTS
  Mean (± standard deviation) IOP in the treated eye reduced (P < 0.001) from 17.17 ± 3.2 mm Hg at baseline to 13.7 ± 2.4 mm Hg at 6 weeks, while that in the untreated eye reduced from 16.4 ± 3.1 mm Hg to 14.8 ± 2.7 mm Hg (P = 0.01). The decrease in IOP in the untreated fellow eye was statistically significant at 8 AM (2.7 mm Hg, P = 0.003) and 11 AM (2.3 mm Hg, P = 0.01) but not so at 2 PM (1.2 mm Hg, P = 0.10) and 5 PM (0.9 mm Hg, P = 0.19). The amount of IOP reduction in the untreated eye was significantly associated with the magnitude of IOP reduction in the treated eye (b = 0.69, P = 0.008).
  
  
  CONCLUSIONS
  Uniocular PGA treatment tends to reduce the IOP of the untreated fellow eye.
authors.affiliation: VST Glaucoma Center; Center for Clinical Epidemiology and Biostatistics, L V Prasad Eye Institute, Banjara Hills, Hyderabad, Andhra Pradesh, India.
authors.forename: Harsha L
authors.initials: HL
authors.lastname: Rao
authors.forename: Sirisha
authors.initials: S
authors.lastname: Senthil
authors.forename: Chandra S
authors.initials: CS
authors.lastname: Garudadri
mesh_terms: D000328:Adult; D000368:Aged; D002940:Circadian Rhythm; D005260:Female; D005500:Follow-Up Studies; D005902:Glaucoma, Open-Angle / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions; D011465:Prostaglandins, Synthetic / Q000008:administration & dosage / Q000627:therapeutic use*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D009883:Ophthalmic Solutions; D011465:Prostaglandins, Synthetic