Intravitreal penetration of levofloxacin administered via irrigating solutions or intracameral injection in aphakic rabbit eyes

1. Takahiro Uda
2. Takashi Suzuki
3. Shiro Kawasaki
4. Yuichi Ohashi

Ophthalmology, Ehime University, Graduate School of Medicine, Toon, Japan.

Purpose: Intraoperative antibiotics in irrigating solutions or intracameral injection of antibiotics are used to prevent postoperative endophthalmitis. However little is known about intravitreal penetration of antibiotics in aphakic eye after these applications. This study was designed to investigate pharmacokinetics of levofloxacin (LVFX) in vitreous cavity (VC) of aphakic rabbit eyes after administration via irrigating solutions or intracameral injection in aphakic rabbit eyes.

Methods: The lens of albino rabbit eye was removed by phacoemulsification (PEA). In one group (IS), LVFX (10µg/ml) was irrigating during the surgery, while, in the other group(IC), 0.1 ml of LVFX (5mg/ml) was injected intracamerally after the surgery. In both groups, a part of the eyes (IS+, IC+) underwent intentional rupture of the posterior capsule at the end of standard PEA procedure. While the other eyes (IS-, IC-) did not have the rupture. Then, the eyes were enucleated 2h after surgery, and the concentration of LVFX in vitreous humor was estimated using high performance liquid chromatography.

Results: Mean ± SD concentrations of LVFX in middle part of VC were as follows: IS-; 0.060±0.014, IS+; 0.410±0.341, IC-; 13.6±6.2μg/g., IC+; 63.0±63.9. High concentration of LVFX was maintained in VC after either IC- or IC+. Furthermore eyes with rupture show LVFX penetrate better to VC.

Conclusions: LVFX in IC was found to far better penetrate into VC, compared to IS. Moreover, the rupture of lens capsule promoted the penetration of LVFX. Thus, IC could be an effective strategy to prevent postoperative bacterial growth in VC.