Corneal penetration of fluoroquinolones: aqueous humor concentrations after topical application of levofloxacin 0.5% and ofloxacin 0.3% eyedrops.
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.
Koch
Hans-Reinhard
HR
Hochkreuzklinik Eye Hospital, Bonn, Germany.
Kulus
Sven C
SC
Roessler
Markus
M
Ropo
Auli
A
Geldsetzer
Klaus
K
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
D000900:Anti-Bacterial Agents; D009883:Ophthalmic Solutions; D064704:Levofloxacin; D015242:Ofloxacin