title: Vitreous concentrations of triamcinolone acetonide in human eyes after intravitreal or subtenon injection.
abstract: OBJECTIVE
  To compare vitreous concentrations of triamcinolone acetonide (TA) achieved by prior therapeutic intravitreal and subtenon injections.
  
  
  METHODS
  Interventional case series.
  
  
  METHODS
  Vitreous samples were collected from patients who required vitreous surgery, six having received a subtenon injection of TA and another six, an intravitreal injection. Vitreous concentrations of TA were measured by high-performance liquid chromatography.
  
  
  RESULTS
  Vitreous concentrations of TA after intravitreal injection were 1.22 +/- 0.24 mug/ml, significantly higher than those after subtenon injection (<0.001 mug/ml, P = .003). Vitreous concentrations of TA after subtenon injection and TA-assisted vitrectomy performed in a few patients to visualize the transparent vitreous gel were 0.20 +/- 0.11 mug/ml, an intermediate amount between these two groups.
  
  
  CONCLUSIONS
  Much higher vitreous concentrations of TA after intravitreal injection than subtenon injection may accelerate therapeutic effect when intravitreal injections are given to reduce macular edema. Subtenon injections of TA may act via the sclera as opposed to the vitreous.
authors.affiliation: Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan. inoshin@sc.itc.keio.ac.jp
authors.forename: Makoto
authors.initials: M
authors.lastname: Inoue
authors.forename: Kayoko
authors.initials: K
authors.lastname: Takeda
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Morita
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yamada
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Tanigawara
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Oguchi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D003238:Connective Tissue / Q000187:drug effects; D004333:Drug Administration Routes; D005205:Fascia / Q000187:drug effects; D005938:Glucocorticoids / Q000493:pharmacokinetics*; D006801:Humans; D007267:Injections; D008875:Middle Aged; D012164:Retinal Diseases / Q000601:surgery; D014222:Triamcinolone Acetonide / Q000493:pharmacokinetics*; D014821:Vitrectomy; D014822:Vitreous Body / Q000187:drug effects / Q000378:metabolism*
chemical_list: D005938:Glucocorticoids; D014222:Triamcinolone Acetonide