Corneal endothelial damage by air bubbles during phacoemulsification
E. K. Kim, S. M. Cristol, D. H. Geroski, B. E. McCarey and H. F. Edelhauser
Department of Ophthalmology, Yonsei University, Seoul, Korea.
OBJECTIVE: To characterize the mechanism by which air bubbles damage the
corneal endothelium during phacoemulsification. MATERIALS AND METHODS: A
series of experiments was conducted to expose the corneal endothelium of
New Zealand white rabbit and human eyes that were obtained from an eye bank
to air under different conditions. Phacoemulsification at different power
settings and irrigation with and without the introduction of air into the
anterior chamber were performed. Corneal endothelial perfusion experiments
were conducted with air bubbles that were introduced into the perfusion
chamber for 2 seconds to 1 hour. Air was also injected into the anterior
chambers of anesthetized rabbits for 2 minutes to 3 hours. Corneas were
stained with nitrobenzo-xadiazole-phallacidin and examined with
fluorescence microscopy. Selected corneas were also examined with scanning
and transmission electron microscopy. RESULTS: Intracameral air bubbles
during phacoemulsification, irrigation, and perfusion studies resulted in a
severe injury to the corneal endothelium in as little as 20 seconds.
Intracameral air bubbles in a living rabbit resulted in a slower injury
that was morphologically different from the more rapid injury. CONCLUSIONS:
Air bubbles in intraocular fluids with a high surface tension can cause a
ring-shaped pattern of damage to the corneal endothelium. The mechanism
that caused this pattern of damage appears to be a surface tension
phenomenon.
