Penetration of topically applied levofloxacin into rabbit lens with thin-wall filtering bleb after filtering surgery

Objectives: To investigate the thin-walled bleb penetration of topical levofloxacin into the rabbit lens. Design: Experimental study. Participants: New Zealand white rabbit. Methods: Twenty-six New Zealand white rabbits with thin-walled blebs after filtering surgery to right eyes were divided randomly into three groups A, B, C. Eight rabbits in each group A and B, and all eyes received 0.1ml of 0.3% levofloxacin 4 times every day, which last for 4 days in group A and 7 days in group B. Ten rabbits with 20 eyes in group C, and 0.1ml of 0.3% levofloxacin was administrated to the eyes at 30 minute intervals for 4 hours. All the rabbits received the last drop administered 30 minutes before been put to death. The concentration of levofloxacin in lens was determined by high-performance liquid chromatography (HPLC). The Student's t-tesi and Chi-square test were used to compare the data of the three groups. A P<0.05 was required for results to be considered statistically significant. Main Outcome Measures: The concentration of levofloxacin in rabbit lens. Results: The concentration of levofloxacin in the lens of thin-walled bleb eyes was 0.33±0.10 μg/g, 0.27±0.15 μg/g and 0.62±0.28 μg/g in groups A, B and C and 0.12±0.03 μg /g, 0.12±0.03 μg/g and 0.15±0.05 μg/g in control eyes of groups A, B and C, and the difference of levofloxacin concentration in lens between brother eyes in each group was statistically significant (group A: P< 0.0001 ;group B: P<0.05;group C: P<0.0001. The difference of levofloxacin concentration in the lens of thin-walled bleb eyes between group A and B was non- statistically significant (P=0.566). But it was statistically significant between either group A and C (P=0.006), or group B and C (P=0.001). Conclusions: Levofloxacin penetrate into rabbit lens better in thin-walled bleb group than in control group, and it seemed that higher concentration of levofloxacin in lens occurred by high frequency administration.