Intracorneal, aqueous humor, and vitreous humor penetration of topical and oral ofloxacin
E. D. Donnenfeld, H. D. Perry, R. W. Snyder, R. Moadel, M. Elsky and H. Jones
Department of Ophthalmology, North Shore University Hospital, Manhasset, NY, USA.
OBJECTIVES: To investigate the intracorneal, aqueous, and vitreous
penetration of ofloxacin, and to assess the concentration of the drug after
topical administration alone and after combined topical and oral
administration. METHODS: Twenty consecutive patients undergoing penetrating
keratoplasty with vitrectomy for bullous keratopathy received 2 drops of
0.3% ofloxacin every 30 minutes starting 4 hours before surgery. Group A
(10 patients) received topical therapy alone. Group B (10 patients)
received an additional 3 doses of oral ofloxacin, 400 mg, every 12 hours
starting 26 hours before surgery. Aqueous humor, vitreous humor, and
corneal specimens were analyzed for ofloxacin levels. RESULTS: For group A,
the mean intracorneal ofloxacin level was 4.51 micrograms/mL (range,
0.58-8.77 micrograms/mL; 10 specimens), the mean aqueous humor level was
1.34 micrograms/mL (range, 0.07-4.98 micrograms/mL; 8 specimens), and the
mean vitreous humor level was 0.37 micrograms/mL (range, 0.05-0.90
micrograms/mL; 8 specimens). For group B, the mean intracorneal ofloxacin
level was 8.59 micrograms/mL (range, 1.18-23.24 micrograms/mL; 10
specimens), the mean aqueous humor level was 2.77 micrograms/mL (range,
0.25-5.80 micrograms/mL; 10 specimens), and the mean vitreous humor level
was 2.55 micrograms/mL (range, 0.28-4.97 micrograms/mL; 9 specimens).
CONCLUSIONS: Topically applied ofloxacin achieves therapeutic levels in the
cornea and aqueous. Mean levels achievable are well above the 90% minimal
inhibitory concentration (MIC90) for the majority of bacteria responsible
for endophthalmitis and corneal ulceration. The addition of oral ofloxacin
to topical therapy increased vitreous penetration 7-fold in this assay
trial.
