Ocular pharmacokinetic study of a corticosteroid by 19F MR.
Traditional ocular pharmacokinetic studies are invasive and cannot be easily applied to humans in vivo. To acquire in vivo ocular pharmacokinetic data noninvasively, (19)F MR on a 3T clinical scanner was used to follow the real time dynamics of a corticosteroid in the eye. (1)H MR was also performed to locate the site of administration. Triamcinolone acetonide phosphate (TAP) was the model drug, administered by intravitreal and subconjunctival injections. TAP pharmacokinetics were monitored by changes in the (19)F spectrum of the intraocular drug in real time. The elimination half-lives of TAP in the eye after intravitreal and subconjunctival injections were 8 and 0.5 h in vivo and 17 and 6.0 h postmortem, respectively. The half-lives associated with clearance were 14 h for intravitreal injection and 0.5 h for subconjunctival injection.
Department of Physics and Astronomy, University of Utah, 115 South 400 East, Salt Lake City, UT 84112, USA.
Xin
X
Liu
S Kevin
SK
Li
Eun-Kee
EK
Jeong
D000818:Animals; D001682:Biological Availability; D003228:Conjunctiva; D005461:Fluorine / Q000032:analysis; D005938:Glucocorticoids / Q000493:pharmacokinetics*; D006207:Half-Life; D007267:Injections; D008279:Magnetic Resonance Imaging; D011817:Rabbits; D014222:Triamcinolone Acetonide / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D014822:Vitreous Body / Q000378:metabolism*
D005938:Glucocorticoids; D005461:Fluorine; C011243:drocinonide phosphate potassium; D014222:Triamcinolone Acetonide