title: Triamcinolone acetonide concentration of aqueous humor after decanted 20-mg intravitreal injection.
abstract: OBJECTIVE
  To characterize the concentration-time profile of triamcinolone acetonide (TA) in human aqueous after a single, 20-mg, intravitreal injection.
  
  
  METHODS
  Case series.
  
  
  METHODS
  Seven patients and 10 eyes that received intravitreal injection of the decanted 20 mg of TA.
  
  
  METHODS
  Fifty microliters of aqueous were sampled from each intravitreally TA-injected eye at postinjection monthly interval and the samples were subjected to liquid chromatography coupled with tandem mass spectrometric detection for TA.
  
  
  METHODS
  The TA concentration in the aqueous.
  
  
  RESULTS
  The TA was cleared from the aqueous in a monoexponential manner with a half-life of 29.6 days and clearance coefficient of 0.0234 (1/day). The extrapolated maximum TA concentration in aqueous was about 3312 ng/ml and the area under the curve was 74,017 day x ng/ml.
  
  
  CONCLUSIONS
  The TA concentration in human aqueous could stay above therapeutic concentration for 150 days (5 half-lives with remaining TA concentration of 104 ng/ml) after a 20-mg intravitreal injection, suggesting an even longer therapeutic concentration of TA in vitreous.
authors.affiliation: Jacob's Retina Center at Shiley Eye Center, Department of Ophthalmology, University of California, San Diego, La Jolla, California 92137-0946, USA. cheng@eyecenter.ucsd.edu
authors.forename: Lingyun
authors.initials: L
authors.lastname: Cheng
authors.forename: Alay S
authors.initials: AS
authors.lastname: Banker
authors.forename: Michael
authors.initials: M
authors.lastname: Martin
authors.forename: Igor
authors.initials: I
authors.lastname: Kozak
authors.forename: William R
authors.initials: WR
authors.lastname: Freeman
mesh_terms: D000328:Adult; D001082:Aqueous Humor / Q000378:metabolism*; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005938:Glucocorticoids / Q000737:chemistry / Q000493:pharmacokinetics*; D006207:Half-Life; D006801:Humans; D007267:Injections; D008297:Male; D008875:Middle Aged; D053719:Tandem Mass Spectrometry; D014222:Triamcinolone Acetonide / Q000737:chemistry / Q000493:pharmacokinetics*; D014822:Vitreous Body
chemical_list: D005938:Glucocorticoids; D014222:Triamcinolone Acetonide