title: Corneal penetration of fluoroquinolones: aqueous humor concentrations after topical application of levofloxacin 0.5% and ofloxacin 0.3% eyedrops.
abstract: OBJECTIVE
  To investigate the penetration of topically applied levofloxacin 0.5% and ofloxacin 0.3% eyedrops into the aqueous humor of patients having cataract surgery.
  
  
  METHODS
  Hochkreuzklinik Eye Hospital, Bonn, Germany.
  
  
  METHODS
  In this randomized, investigator-masked study, 69 patients received 4 drops of either levofloxacin 0.5% or ofloxacin 0.3% eyedrops within 1 hour (60 min, 45 min, 30 min, and 15 min) of elective cataract surgery. Aqueous humor samples of at least 50 muL were drawn from the anterior chamber at the beginning of the cataract operation. The concentrations of the fluoroquinolones in the anterior chambers were measured using high-performance liquid chromatography. To exclude a dilution effect of the anterior chamber (AC), they were related to the AC volumes (measured by 3-dimensional modeling of central Orbscan [Bausch & Lomb] slit-image photos) and AC depths (measured by ultrasound).
  
  
  RESULTS
  The mean concentration of levofloxacin (1139.9 ng/mL +/- 717.1 [SD]) in the aqueous humor was significantly higher (P = .0008) than that of ofloxacin (621.7 +/- 368.7 ng/mL). The aqueous humor concentrations correlated negatively with the measured volumes and depths of the ACs.
  
  
  CONCLUSIONS
  The new fluoroquinolone, levofloxacin, is more soluble in water enabling the use of higher drug concentrations (0.5%) compared with other currently available fluoroquinolone eyedrops (0.3%). The concentration AC with levofloxacin eyedrops was about 2-fold that reached with ofloxacin eyedrops. The concentration of the antibacterial isomer was approximately 3.5 to 4 times higher when levofloxacin was administered, assuming negligible stereoselective uptake.
authors.affiliation: Hochkreuzklinik Eye Hospital, Bonn, Germany.
authors.forename: Hans-Reinhard
authors.initials: HR
authors.lastname: Koch
authors.forename: Sven C
authors.initials: SC
authors.lastname: Kulus
authors.forename: Markus
authors.initials: M
authors.lastname: Roessler
authors.forename: Auli
authors.initials: A
authors.lastname: Ropo
authors.forename: Klaus
authors.initials: K
authors.lastname: Geldsetzer
mesh_terms: D000287:Administration, Topical; D000368:Aged; D000867:Anterior Chamber / Q000033:anatomy & histology; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D001082:Aqueous Humor / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003315:Cornea / Q000378:metabolism*; D005260:Female; D006801:Humans; D064704:Levofloxacin; D008297:Male; D015242:Ofloxacin / Q000493:pharmacokinetics*; D009883:Ophthalmic Solutions / Q000493:pharmacokinetics; D018918:Phacoemulsification
chemical_list: D000900:Anti-Bacterial Agents; D009883:Ophthalmic Solutions; D064704:Levofloxacin; D015242:Ofloxacin