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Published on: July 23, 2016
Safety of Intracameral Injection of Minimal Bactericidal Concentration of Povidone Iodine on the Corneal Endothelium
Rania S ElKitkat1, Weam M Ebeid, Eman K Habib
1Departments of *Ophthalmology; and †Anatomy and Embryology, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
Purpose:
To investigate the safety of intracameral injection of minimum bactericidal concentration (MBC) of povidone iodine (PI) on the corneal endothelium in a rabbit model as a proposed method of prophylaxis against postoperative endophthalmitis.
Methods:
We included 32 New Zealand white rabbits in the study. Twenty-four rabbits received intracameral injections of 0.1 mL of 0.25% PI, and they were sequentially killed at intervals; first, seventh, and 14th day. The control group included 4 rabbits that received intracameral injections of 0.1 mL normal saline, and 4 rabbits that underwent the same intraocular procedure without injections (sham operated). Slit-lamp examination and ultrasonic corneal pachymetry were performed before and after injections for both eyes. The corneas were histopathologically examined by light and electron microscopy.
Results:
MBC of PI (0.25%) was toxic to rabbits' corneal endothelium as evident by histopathological changes, corneal edema, and increased corneal thickness on day 1. Signs of healing were obvious on day 7 and were almost complete on day 14, as detected by histopathology, subsidence of corneal edema, and normalization of corneal thickness.
Conclusions:
MBC (0.25%) of PI was found toxic to the rabbits' corneal endothelium, with progressive regeneration and complete healing within 2 weeks. To our knowledge, we are the first to use MBC of PI in intracameral injection trials. Further studies on primates, which have more comparable regenerative capacity to humans' corneal endothelium, are encouraged to evaluate their endothelial healing response.
Insights
Intracameral injection of minimum bactericidal concentration (MBC) of povidone iodine (PI) showed toxicity to rabbit corneal endothelium. However, complete healing occurred within two weeks, suggesting potential for future research in endophthalmitis prophylaxis.
Area of Science:
- Ophthalmology
- Microbiology
- Toxicology
Background:
- Postoperative endophthalmitis is a severe complication following intraocular surgery.
- Povidone-iodine (PI) is commonly used for surface antisepsis, but its intracameral safety is not well-established.
- Minimum bactericidal concentration (MBC) of PI is proposed for endophthalmitis prophylaxis.
Purpose of the Study:
- To evaluate the safety of intracameral injection of MBC of PI on corneal endothelium.
- To assess the regenerative capacity of the corneal endothelium after PI exposure.
- To investigate PI's potential as an endophthalmitis prophylactic agent.
Main Methods:
- 32 New Zealand white rabbits were used.
- Intracameral injections of 0.25% PI or saline were administered.
- Corneal endothelium was examined via slit-lamp, pachymetry, and histopathology at intervals.
Main Results:
- 0.25% PI caused corneal edema, increased thickness, and histopathological damage on day 1.
- Signs of healing were observed by day 7.
- Corneal edema subsided and thickness normalized by day 14, indicating significant regeneration.
Conclusions:
- MBC (0.25%) of PI is toxic to rabbit corneal endothelium but demonstrates progressive regeneration and complete healing within 2 weeks.
- This is the first study to use MBC of PI in intracameral injection trials.
- Further primate studies are recommended to assess endothelial healing in a more human-comparable model.
