Abstract
Purpose: :
Intracameral (IC) administration of antimicrobial and anti-inflammatory agents during intraocular surgery has been proposed to decrease the need for post-operative topical drops. However, free drugs are cleared with the aqueous humor (AH) and the purpose of this study is to explore the potential role of nanoparticles for longer-term delivery of medications to the anterior chamber (AC), by evaluating the clearance rates and complications associated with IC nanoparticles.
Methods: :
Nine rabbit eyes were used in this study. Baseline fluorescence and intraocular pressures (IOP) were assessed. Groups included: Control- 100 µL of IC saline; Uncoated- 100 µL of IC 200 nm uncoated latex particles; and Coated- 100 µL of IC 200 nm latex particles, coated to prevent aggregation. The particles were linked to fluorescence tags, allowing detection by in vivo fluorescence. Fluorescence images and IOP measurements were obtained at 0 min, 1 hr, 6 hrs, daily for 1 week and every 2 days for 1 month. Relative particle retention was evaluated by comparing fluorescence images to those obtained at t=0.
Results: :
There was no fluorescence in the control group. There was particle loss immediately after injection in both experimental groups; 58% of the uncoated and 36% of the coated particles remained after 1 day. Following this decline, there was a gradual loss of particles; 41% of the uncoated and 22% of the coated particles remained after 15 days. After 30 days, 33% and 18% of the total particles were retained, in the coated and uncoated groups, respectively. There was a significantly greater clearance of uncoated particles (P<0.05). Only 1 animal, from the uncoated group developed elevated IOP after the injection, which resolved progressively within 16 days.
Conclusions: :
These results suggest that intraoperative IC injection of nanoparticles may be a useful tool for providing sustained delivery of post-operative medications to the AC for up to 1 month.
Keywords: anterior chamber • antibiotics/antifungals/antiparasitics