Abstract
Purpose: :
To evaluate human corneal endothelial mucin layer thickness after phacoemulsification & irrigation/aspiration (I/A) with the Next Generation Ocular Irrigating Solution (NGOIS), which contains a polymer that modifies both surface tension and viscosity, so that it is similar to that of aqueous humor.
Methods: :
Paired human corneas (n = 14) were mounted in an artificial anterior chamber with a volume of 400 µL. Nine corneas were exposed to 3 minutes of ultrasound (US) at 80% power using the Alcon SERIES 20000® LEGACY® surgical system, followed by 250 mL of irrigation using NGOIS at a flow rate of 40 cc/min. Five corneas were exposed to 2 minutes of pulsed US at 50% power, 50 % of the time at 20 pps using the Alcon INFINITI® Vision System, followed by 250 mL of irrigation using NGOIS at a flow rate of 50 cc/min. The other corneas of the pairs were exposed to the same instrument settings using BSS PLUS®. The corneas were divided in half and fixed for mucin staining and transmission electron microscopy (TEM). The mucin layer thickness was measured on the TEM prints.
Results: :
The mucin layer thickness in the continuous phacoemulsification group (3 min US, 80% power, SERIES 20000® LEGACY® surgical system) was 0.76 ± 0.28 µm (mean ± SD) with NGOIS and 0.52 ± 0.34 µm with BSS PLUS®. The difference was statistically significant (p =0.0003). The mucin layer thickness in the pulsed phacoemulsification group (2 min US, 50% power, 50 % of the time, 20 pps, INFINITI® Vision System) was 1.52 ± 0.43 µm (mean ± SD) with NGOIS and 1.09 ± 0.21 µm with BSS PLUS®. The difference was statistically significant (p = 0.00005).
Conclusions: :
In an in situ corneal model, NGOIS provides improved protection to the corneal endothelial mucin layer from the effects of phacoemulsification and I/A using both continuous and pulsed US at flow rates of 40 and 50 cc/min. The added polymer in NGOIS reduces surface tension and increases viscosity, allowing for both maintenance of the mucin layer attachment integrity and for a statistically significant difference in the post–phacoemulsification mucin layer thickness. The advantage of NGOIS was evident with both the INFINITI® Vision System and the SERIES 20000 ® LEGACY ® surgical system.
Keywords: cataract • cornea: endothelium